NOSOCOMIAL INFECTION
Diagnosis,
Diagnostics, Immunodiagnosis & Immunodiagnostics:
January 2003
6199.
Baddi L, Ray D. An unusual nosocomial pneumonia. Chest. 2002
Sep;122(3):1077-9. No abstract.
6200.
Fabrizi F, Poordad FF, Martin P. Hepatitis C infection and the patient
with end-stage renal disease. Hepatology. 2002 Jul;36(1):3-10. Review.
Hepatitis
C virus (HCV) remains common in patients with end-stage renal disease (ESRD) and
is an important cause of liver disease in this population. Acquisition of HCV
infection continues to occur in dialysis patients because of nosocomial spread.
The natural history of HCV in dialysis patients remains controversial because
the course of HCV typically extends over decades, whereas dialysis patients have
higher morbidity and mortality rates than those of the general population
limiting long-term follow-up. However, recent reports suggest that HCV infection
affects the survival of chronic dialysis patients as well as renal transplant (RT)
recipients. The severity of preexisting liver disease on pretransplantation
liver biopsy may provide useful prognostic information about clinical outcome
after RT; liver biopsy should be incorporated in the evaluation and management
of RT candidates with HCV. Recent surveys with long-term follow-up have
documented adverse effects of HCV on patient and graft survival. Use of renal
grafts from HCV-infected donors in recipients with HCV does not appear to result
in a greater burden of liver disease albeit with short-term follow-up. There is
only limited data about interferon (IFN) therapy in chronic dialysis patients,
although sustained responses are reported. Preliminary data on IFN plus
ribavirin therapy in dialysis patients with hepatitis C have given encouraging
results, but randomized trials are needed. Interferon remains contraindicated
post-RT because of concern about precipitating graft dysfunction.
6201.
Harmanci A, Harmanci O, Akova M. Hospital-acquired pneumonia: challenges
and options for diagnosis and treatment. J Hosp Infect. 2002 Jul;51(3):160-7.
Review.
The
management of hospital-acquired pneumonia (HAP) presents a major challenge for
the clinician. The insensitivity of current diagnostic methods and the
increasing prevalence of nosocomial pathogens with multiple antibiotic
resistance complicate the issue. Use of mechanical ventilation and
broad-spectrum antimicrobials in the intensive care setting predipose patients
to acquire HAP more frequently with antimicrobial-resistant pathogens.
Controversy exists regarding the patients in which invasive diagnostic testing
is indicated; the timing of these procedures is another subject of debate.
Proper empirical therapy is fundamental to a favourable outcome, and the
selection of inappropriate agents to which pathogens are resistant contributes
significantly to morbidity and mortality. In general, there is agreement on the
requirement for a thorough knowledge of the local causative organisms and the
pathogens' resistance profiles. A wide variety of antimicrobials can be used
either as monotherapy or in combinations.
6202.
Lodha R, Chandra U, Natchu M, Nanda M, Kabra S K. Nosocomial infections
in pediatric intensive care units. Indian J Pediat 2001; 68(11), 1063-70.
6203.
Moore KN, Day RA, Albers M. Pathogenesis of urinary tract infections: a
review. J Clin Nurs. 2002 Sep;11(5):568-74. Review.
Pathogenesis
of urinary tract infections (UTIs) is not well-understood. In this paper, we
review the current understanding of UTIs, particularly in relationship to
individuals using intermittent catheterization. Relationships exist between the
human host, infectious agent and the environment. In the human host, the urethra
connects the bladder to potential infectious agents on the perineum. A
high-pressure zone exists within the urethra at a point where the urethra passes
through the urogenital diaphragm. This zone creates a natural barrier to ascent
of organisms colonized in the distal urethra and the bladder itself has natural
defences against invading organisms. The interaction of host defences with
bacteria (infectious agent) determines whether or not the bacteria persist. A
small number of bacteria and some types of bacteria are controlled more
effectively by natural bladder defence mechanisms and frequent bladder emptying
than a large number of bacteria. Escherichia coli, coliforms and enterococci are
considered common bacterial causes of UTIs and are found in high numbers on the
perineum. Intermittent catheterization is an effective way of bladder emptying
but as an invasive procedure it remains a risk factor in the development of UTI.
Pathogenesis:
6204.
Bradley SJ, Kaufmann ME, Happy C, Ghori S, Wilson AL, Scott GM. The
epidemiology of glycopeptide-resistant enterococci on a haematology
unit--analysis by pulsed-field gel electrophoresis. Epidemiol Infect. 2002
Aug;129(1):57-64.
As
part of an interventional study to determine glycopeptide-resistant enterococci
(GRE) acquisition on a three-ward haematology unit, rectal swabs were taken
weekly from 293 patients recruited to the study between June 1995 and December
1996. The GRE isolates obtained from the first positive rectal swab from 120
colonized patients, the isolates from 7 patients with clinical infection and 43
isolates obtained from the ward environment were compared by pulsed-field gel
electrophoresis (PFGE). Sixty-three of 120 patients were colonized by one of
strains A-H, while 49 were colonized by unique strains. The first 18 weeks were
associated with the highest prevalence of GRE by rectal swab, with a single
strain A responsible for 52% of acquisitions on ward 2, 22% on ward 3 and 36% on
ward 4. Other smaller ward associated clusters were evident. Environmental
sampling of ward 2 during this time showed that all but 2 of 30 isolates were
indistinguishable from strain A. As the GRE prevalence fell, rectal swab and
environmental isolates became more heterogeneous, and strain A disappeared after
week 55. GRE prevalence rose again in the final 15 weeks of the study, and a new
predominant strain B emerged on ward 2 responsible for 50% of new acquisitions.
In the seven patients with clinical infection with GRE, the clinical isolates
were compared with the contemporaneous rectal swab isolate, and were found to be
the same in only two cases. An analysis of five long-term carriers colonized for
a median of 19 weeks (range 11-34) showed colonization with at least two and in
one case six distinct strains, raising the question of how many strains may be
colonizing a patient at any one time, and suggesting that multiple colonies
should be analysed. These data suggest that cross-infection was an important
factor in the spread of GRE when the colonization rate was high.
6205.
Canet JJ, Juan N, Xercavins M, Freixas N, Garau J. Hospital-acquired
pneumococcal bacteremia. Clin Infect Dis. 2002 Sep 15;35(6):697-702.
To
assess the most relevant features of hospital-acquired pneumococcal bacteremia,
all cases of pneumococcal bacteremia at a single teaching hospital that occurred
during 1988-2000 were prospectively studied. During this period, 374 cases of
pneumococcal bacteremia were documented; 39 (10%) of these episodes were
hospital acquired. Twenty-nine (74%) cases occurred during the period of
December through May. Eleven (28%) of 39 patients had received antimicrobial
agents in the month before the onset of bacteremia. All patients had underlying
diseases that predisposed them to pneumococcal infection. The most common origin
of infection was the respiratory tract, followed by the intra-abdominal region.
Fifteen strains were fully susceptible to penicillin, and 20 were intermediately
resistant. Only 25 strains were susceptible to erythromycin; all strains that
were resistant to erythromycin were penicillin nonsusceptible. Eighteen (46%) of
39 patients died; the mortality rate related to infection was 39%.
6206.
Cespedes C, Miller M, Quagliarello B, Vavagiakis P, Klein RS, Lowy FD.
Differences between Staphylococcus aureus isolates from medical and nonmedical
hospital personnel. J Clin Microbiol. 2002 Jul;40(7):2594-7.
It
is unclear whether the levels of Staphylococcus aureus colonization of hospital
personnel with patient exposure are increased or whether personnel become
colonized with more antibiotic-resistant strains. Differences in nasal and hand
carriage of S. aureus between medical and nonmedical hospital personnel were
examined. No differences in nasal carriage between the two groups were found;
however, there was a trend that suggested differences in the rates of hand
carriage of S. aureus (18% of nonmedical personnel and 10% of medical
personnel). Medical personnel were colonized with more antibiotic-resistant
isolates than nonmedical personnel (mean, 2.8 versus 2.1 isolates [P <
0.03]), and the strain profiles indicated that they tended to be more clonal in
origin, suggesting that exposure to hospital isolates alters the colonization
profile.
6207.
Girou E, Loyeau S, Legrand P, Oppein F, Brun-Buisson C. Efficacy of
handrubbing with alcohol based solution versus standard handwashing with
antiseptic soap: randomised clinical trial. BMJ. 2002 Aug 17;325(7360):362.
OBJECTIVE:
To compare the efficacy of handrubbing with an alcohol based solution versus
conventional handwashing with antiseptic soap in reducing hand contamination
during routine patient care. DESIGN: Randomised controlled trial during daily
nursing sessions of 2 to 3 hours. SETTING: Three intensive care units in a
French university hospital. PARTICIPANTS: 23 healthcare workers. INTERVENTIONS:
Handrubbing with alcohol based solution (n=12) or handwashing with antiseptic
soap (n=11) when hand hygiene was indicated before and after patient care.
Imprints taken of fingertips and palm of dominant hand before and after hand
hygiene procedure. Bacterial counts quantified blindly. MAIN OUTCOME MEASURES:
Bacterial reduction of hand contamination. RESULTS: With handrubbing the median
percentage reduction in bacterial contamination was significantly higher than
with handwashing (83% v 58%, P=0.012), with a median difference in the
percentage reduction of 26% (95% confidence interval 8% to 44%). The median
duration of hand hygiene was 30 seconds in each group. CONCLUSIONS: During
routine patient care handrubbing with an alcohol based solution is significantly
more efficient in reducing hand contamination than handwashing with antiseptic
soap.
6208.
Goldmann DA. Blood-borne pathogens and nosocomial infections. J Allergy
Clin Immunol. 2002 Aug;110(2 Suppl):S21-6. Review.
Guidelines
to prevent the transmission of blood-borne infections have evolved rapidly since
the recognition that "serum hepatitis" could be transmitted to health
care personnel via percutaneous exposure to blood. The HIV epidemic focused
renewed attention on the problem of protecting health care personnel,
culminating in "standard precautions" for patient care, which
emphasized the use of gloves for all contact with blood and body fluids. This
focus on protection of the health care worker sometimes obscures the other
important functions of gloves: protection of patients from microorganisms on the
hands of providers and prevention of patient-to-patient transmission of
nosocomial pathogens. The risk of infection after percutaneous exposure to the 3
major blood-borne viruses-hepatitis B virus (HBV), hepatitis C virus (HCV), and
HIV-varies greatly. The risk for a nonimmune individual exposed to HBV may be
>30% if the source is Hb(e)Ag-positive. The average infection rate for HCV is
1.8%. For HIV, the average risk is 0.3%, but is higher with deep injury, when
there is visible blood on the device, when a needle has been in an artery or
vein, or when the source patient is in the terminal phase of HIV. Prompt
administration of anti-HIV therapy reduces risk by about 80%. Mucous membrane
and cutaneous exposures carry less risk. Recent efforts to reduce needlestick
injuries in
hospitals
have reduced the risk to health care providers. Surgeons and other health care
professionals who are infected with HIV or HCV pose a very small risk to their
patients, although a number of outbreaks have been traced to surgeons who are
HBV carriers; most have been Hb(e)Ag-positive.
6209.
Kaminska W, Patzer J, Dzierzanowska D. Urinary tract infections caused by
endemic multi-resistant Enterobacter cloacae in a dialysis and transplantation
unit. J Hosp Infect. 2002 Jul;51(3):215-20.
In
the period 1994-1998, 42 multi-resistant Enterobacter cloacae isolates
responsible for urinary tract infections (UTIs) were obtained from children
hospitalized in our dialysis and transplantation unit. E. cloacae isolates
obtained between 1994 and 1996 were susceptible to aminoglycosides, carbapenems
and fluoroquinolones, whereas E. cloacae isolates obtained between 1997 and 1998
were susceptible to carbapenems and fluoroquinolones, only. All isolates were
characterized by use of the polymerase chain reaction-based random amplification
of polymorphic DNA and pulsed-field gel electrophoresis. It was found that the
majority of multiresistant E. cloacae isolates obtained during 1997-1998, and
all isolates obtained during 1994-1996, belonged to predominant clones A or B.
These strains were responsible for gastrointestinal tract colonization and UTI
of renal transplant recipients for several years, and persisted as endemic E.
cloacae strains in the dialysis and transplantation unit from 1994 to 1998.
6210.
Mehall JR, Kite CA, Gilliam CH, Jackson RJ, Smith SD. Enteral feeding
tubes are a reservoir for nosocomial antibiotic-resistant pathogens. J Pediatr
Surg. 2002 Jul;37(7):1011-2.
BACKGROUND:
Patients and their surroundings are known reservoirs for nosocomial pathogens.
Enteral feeding tubes and formula are not thought of as reservoirs for
nosocomial organisms. METHODS: A prospective observation study was conducted
comparing methicillin-resistant Staphylococcus aureus (MRSA) and vancomycin-resistant
Enterococcus (VRE) cultured from nosocomial infections and MRSA/VRE cultured
from enteral feeding tubes used in the same neonatal intensive care unit during
the same time period but in different babies. DNA fingerprinting then was used
to compare MRSA and VRE cultured from feeding tubes with MRSA/VRE isolates
cultured from clinical infections. RESULTS: There were 23 S aureus isolates; 12
of 23 were methicillin resistant (MRSA). There were 4 MRSA infections in
patients without feeding tubes. DNA fingerprinting showed that the MRSA species
causing each of the clinical infections also was found in the feeding tubes of
other babies. There were no vancomycin-resistant Enterococcus infections during
the study period. CONCLUSION: Feeding tubes are a reservoir for
antibioticresistant pathogens that can be transmitted to other infants.
Copyright 2002, Elsevier Science (USA). All rights reserved.
6211.
Peacock SJ, Moore CE, Justice A, Kantzanou M, Story L, Mackie K, O'Neill
G, Day NP. Virulent combinations of adhesin and toxin genes in natural
populations of Staphylococcus aureus. Infect Immun. 2002 Sep;70(9):4987-96.
Most
cases of severe Staphylococcus aureus disease cannot be explained by the action
of a single virulence determinant, and it is likely that a number of factors act
in combination during the infective process. This study examined the
relationship between disease in humans and a large number of putative virulence
determinants, both individually and in combination. S. aureus isolates (n = 334)
from healthy blood donors and from patients with invasive disease were compared
for variation in the presence of 33 putative virulence determinants. After
adjusting for the effect of clonality, seven determinants (fnbA, cna, sdrE, sej,
eta, hlg, and ica) were significantly more common in invasive isolates. All
seven factors contributed independently to virulence. No single factor
predominated as the major predictor of virulence, their effects appearing to be
cumulative. No combinations of the seven genes were either more or less likely
to cause disease than others with the same number of virulence-associated genes.
There was evidence of considerable horizontal transfer of genes on a background
of clonality. Our findings also suggested that allelic variants of a polymorphic
locus can make different contributions to the disease process, further study of
which is likely to expand our understanding of staphylococcal disease
pathogenesis.
6212.
Rigau-Perez JG. Modes of transmission of hemorrhagic Fever. JAMA. 2002
Aug 7;288(5):571; discussion 571. No abstract.
6213.
Sartor C, Limouzin-Perotti F, Legre R, Casanova D, Bongrand MC, Sambuc R,
Drancourt M. Nosocomial Infections
with Aeromonas hydrophila from Leeches. Clin Infect Dis. 2002 Jul 1;35(1):E1-5.
The
manner in which leeches are maintained before they are used for therapy has not
been studied as a factor contributing to nosocomial infections. A 5-year
retrospective survey of Aeromonas hydrophila nosocomial infections at a hospital
in Marseille, France, revealed infections in 5 (4.1%) of an estimated 122
patients treated with leeches in the Hand Surgery Unit and 2 (2.4%) of an
estimated 85 patients treated with leeches in other hospital units. The
retrospective survey showed that the Hand Surgery Unit was the only unit that
had its own aquarium for maintaining leeches; this aquarium was filled with tap
water contaminated with Aeromonas species and was not regularly disinfected or
cleaned. Leeches used in other units were maintained in noncarbonated water in a
transport device. Use of leeches kept in aquariums that are filled with tap
water and not disinfected or cleaned regularly may be linked to A. hydrophila
infections.
6214.
Singh N, Stout JE, Yu VL. Legionnaires's disease in a transplant
recipient acquired from the patient's home: implications for management.
Transplantation. 2002 Sep 27;74(6):755-6. No abstract.
6215.
Weber DJ, Rutala WA. Managing the risk of nosocomial transmission of
prion diseases. Curr Opin Infect Dis. 2002 Aug;15(4):421-5. Review.
PURPOSE
OF REVIEW: Prion diseases such as Creutzfeldt-Jakob disease represent a unique
infection control problem because prions exhibit an unusual resistance to
conventional chemical and physical decontamination methods. This paper reviews
the recent literature and provides recommendations for the prevention of
nosocomial transmission of prion agents. RECENT FINDINGS: Recommendations to
prevent the cross-transmission of infection from medical devices potentially
contaminated with prions have been based primarily on prion inactivation
studies. Newer recommendations consider inactivation data, but also use
epidemiological studies of prion transmission, the infectivity of human tissues,
and the efficacy of removing microbes by cleaning. Prion-specific disinfection/sterilization
is required in only limited settings. Healthcare workers are not at risk of
acquiring transmissible spongiform encephalopathies. Blood or blood products
have not been demonstrated to be vehicles for transmission. SUMMARY: On the
basis of scientific data, only critical (e.g. surgical instruments) and
semicritical devices contaminated with high-risk tissue (i.e. brain, spinal
cord, eye) from high-risk patients (e.g. with known or suspected
Creutzfeldt-Jakob disease) require special treatment.
Vaccines:
6216.
Harrison J, Abbott P. Vaccination against influenza: UK health care
workers not on-message. Occup Med (Lond). 2002 Aug;52(5):277-9.
Vaccination
of health care workers against influenza is considered to be important as a
means of protecting patients from nosocomial infection. Vaccine uptake rates
have been reported to be no more than 40% and often between 20 and 30%. An
evaluation of the performance of UK National Health Service trusts, following a
governmental directive to implement vaccination during the winter of 2000-2001,
has shown a poor uptake of vaccine. Reasons for accepting or declining vaccine
are discussed. There is a need for global leadership on this issue to promote
the value of vaccination and to change the behaviour of health care workers.
Therapy:
6217.
Franzin L, Cabodi D, Fantino C. Evaluation of the efficacy of ultraviolet
irradiation for disinfection of hospital water contaminated by Legionella. J
Hosp Infect. 2002 Aug;51(4):269.
We
evaluated the efficacy of the ultraviolet irradiation on hospital water
colonized by Legionella pneumophila serogroup 3, by inserting a lamp system on a
hot water pipe supplying a small area. Cultures were performed for four months
from 5L samples of water, collected before and after the ultraviolet treatment
at the lamp unit and from two distal points. Irradiation was effective
immediately after disinfection (<10 cfu/L), even when the incoming water was
highly contaminated. One distal point showed little or no contamination
(<10-20 cfu/L), while the other showed little to moderate contamination
(<10(3) cfu/L). We conclude that ultraviolet irradiation is useful to protect
the water system in small area; however, because of the lack of residual
activity, it should be combined with other methods of disinfection. Maintenance
of the water system is also necessary in order to reduce biofilm formation and
Legionella recolonization.
6218.
Harmanci A, Harmanci O, Akova M. Hospital-acquired pneumonia: challenges
and options for diagnosis and treatment. J Hosp Infect. 2002 Jul;51(3):160-7.
Review.
The
management of hospital-acquired pneumonia (HAP) presents a major challenge for
the clinician. The insensitivity of current diagnostic methods and the
increasing prevalence of nosocomial pathogens with multiple antibiotic
resistance complicate the issue. Use of mechanical ventilation and
broad-spectrum antimicrobials in the intensive care setting predipose patients
to acquire HAP more frequently with antimicrobial-resistant pathogens.
Controversy exists regarding the patients in which invasive diagnostic testing
is indicated; the timing of these procedures is another subject of debate.
Proper empirical therapy is fundamental to a favourable outcome, and the
selection of inappropriate agents to which pathogens are resistant contributes
significantly to morbidity and mortality. In general, there is agreement on the
requirement for a thorough knowledge of the local causative organisms and the
pathogens' resistance profiles. A wide variety of antimicrobials can be used
either as monotherapy or in combinations.
6219.
Pellowe CM, MacRae ED, Loveday HL, Reid P, Harper P, Robinson N, Pratt R.
The scope of guidelines to prevent healthcare-associated infections. Br J
Community Nurs. 2002 Jul;7(7):374-8.
As
care is increasingly delivered in the community rather than acute settings,
there has been concern that this might be accompanied by a rise in
healthcare-associated infection. Consequently, the National Institute for
Clinical Excellence (NICE) has commissioned a set of infection prevention
guidelines for healthcare workers in community and primary care. The guideline
developers were anxious to concentrate this guidance on the areas of most
concern to practitioners, particularly in relation to devices. This article
describes how a survey and focus groups were employed to identify the areas for
guideline development, namely standard principles, long-term indwelling urinary
catheters, enteral feeds and central intravascular devices.
6220.
Rello J, Lorente C, Bodi M, Diaz E, Ricart M, Kollef MH. Why do
physicians not follow evidence-based guidelines for preventing
ventilator-associated pneumonia?: a survey based on the opinions of an
international panel of intensivists. Chest. 2002 Aug;122(2):656-61.
OBJECTIVE: Adherence to clinical practice guidelines is highly variable. Our objective was to review barriers to physicians' adherence to evidence-based guidelines (EBGs) for preventing ventilator-associated pneumonia (VAP). METHODS: A questionnaire was administered to 110 opinion leaders on VAP from 22 countries to indicate whether 33 pharmacologic and nonpharmacologic practices that had been listed in a recent publication had been implemented in their ICUs. If these prevention strategies were not used, the respondents were asked to indicate one of seven reasons for nonadherence, with the objective of identifying barriers to adherence to EBGs. RESULTS: The overall nonadherence rate was 37.0%. The nonadherence rate was 25.2% for strategies recommended for clinical use, compared with 45.6% for strategies with less effectiveness (odds ratio [OR], 1.80). Pharmacologic strategies had a higher degree of nonadherence than nonpharmacologic strategies (OR, 2.92). Nonadherence to recommendations graded A, B, C, D, and U based on an objective assessment of the consistency of the supporting evidence was 41.3%, 35.7%, 16.0%, 45.7%, and 20.8%, respectively. The most common reasons for nonadherence were the following: disagreement with interpretation of clinical trials (35%); unavailability of resources (31.3%); and costs (16.9%). CONCLUSION: We conclude that nonadherence to EBGs for preventing VAP was common and largely uninfluenced by the degree of evidence. A rational approach toward improving VAP guideline adherence should take into account the heterogeneous factors that influence physician adherence to them.
April 2003
6827.
Carrico
R. Infection control in today's healthcare environment. Ky Nurse. 2002
Oct-Dec;50(4):8-9.No abstract.
6828.
Garbino
J, Kolarova L, Rohner P, Lew D, Pichna P, Pittet D. Secular trends of candidemia
over 12 years in adult patients at a tertiary care hospital. Medicine
(Baltimore). 2002 Nov;81(6):425-33.
The
incidence of fungal infections has been increasing for the last 3 decades,
especially among neutropenic, cancer, and critically ill patients. These
infections are associated with high mortality rates. We retrospectively reviewed
medical charts of adult patients with fungemia from 1989 to 2000 at our
institution. The characteristics of the population groups served by the hospital
were described. Of 328 patients with fungemia, we reviewed 315 (96%) medical
records, and focused on those with candidemia (n = 294). The species
distribution in patients with candidemia showed that the most commonly
identified species were Candida albicans (66%), followed by C. glabrata (17%),
and C. parapsilosis (6%). The incidence of candidemia ranged from 0.2 to 0.46
per 10,000 patient-days with the highest incidence in 1993 and the lowest in
1997. Although most studies show an increased incidence of candidemia, we
observed a reduction over the study period. Furthermore, we observed no shift
from C. albicans to non-albicans Candida species despite a significant increase
in the use of fluconazole. The overall mortality among patients with candidemia
was 44%, with the highest rate in patients over 65 years (52%). Factors
independently associated with higher mortality were patient age greater than 65
years, intensive care unit admission, and underlying cancer.
6829.
Mehata
A P ,Rodrigues C, Sheth K, Jain S, Hakimiyan A ,FazalBhoy N.Control of
methicillin resistant Staphylococcus aureus in a tertiary care centre a five
year study .Indian J med Microbiol 1998,16(1),31-4. (ISA 013431, Vol 38 No13 ,1 July 2002)
Pathogensis:
6830.
Baughman
RP. Antibiotic resistance in the intensive care unit. Curr Opin Crit Care. 2002
Oct;8(5):430-4.
The
increase in antibiotic resistance over the past 10 years can be traced to
several factors. This includes exogenous transmission of bacteria, usually by
hospital personnel. The use of potent antibiotics also can select for resistant
bacteria initially present in low quantities. Strategies to reduce antibiotic
resistance can be tailored to specific outbreaks in a given ICU. General
strategies for reducing antibiotic resistance, on the other hand, include
varying the agents used in the ICU over time. Reduction of the duration of
therapy may prove to be another method of reducing antibiotic resistance.
Vaccines:
6831. Morgan R, Tan C, O'Donnell C, Bresnitz E. Influenza review and outlook. 2002-2003, with additional considerations for differentiation from inhalation anthrax. N J Med 2002 Oct;99(10):21-6; quiz 26-8. No abstract.
July 2003
7403.
Beutz M, Sherman G, Mayfield J, Fraser VJ, Kollef MH.
Clinical utility of blood cultures drawn from central vein catheters and
peripheral venipuncture in critically ill medical patients. Chest. 2003
Mar;123(3):854-61.
STUDY OBJECTIVE: To determine the sensitivity, specificity, and positive and negative predictive values of blood cultures obtained through a central vein catheter compared with peripheral venipuncture. DESIGN: Prospective cohort study. SETTING: A medical ICU (19 beds) from a university-affiliated urban teaching hospital. PATIENTS: Between February 2001 and October 2001, 300 paired blood culture specimens were obtained from 119 patients (2.52 paired cultures per patient). INTERVENTION: Prospective patient surveillance and data collection. Measurements and main results: Thirty-four paired culture results (11.3%; 95% confidence interval, 7.8 to 14.8%) were accepted as true-positives representing a true bacteremia. The sensitivity of catheter-drawn and peripheral venipuncture samples was 82.4% and 64.7%, respectively, and specificity was 92.5% and 95.9%. The positive predictive value was 58.3% for catheter-drawn samples and 66.7% for peripheral venipuncture samples, and the respective negative predictive values were 97.6% and 95.5%. CONCLUSIONS: In critically ill medical patients, the negative predictive value of blood samples obtained by catheter draw or peripheral venipuncture for suspected bloodstream infection is good. However, the sensitivity of blood samples obtained by either catheter draw or peripheral venipuncture alone is not adequate to recommend the elimination of blood samples obtained from the other site. Clinicians should also be aware that additional blood samples may be necessary when interpreting positive blood culture results for common skin or central vein catheter contaminants.
7404.
Brasel KJ, Allen B, Edmiston C, Weigelt JA.
Correlation of intracellular organisms with quantitative endotracheal
aspirate. J Trauma. 2003 Jan;54(1):141-4; discussion 144-6.
BACKGROUND: The presence of intracellular organisms (ICOs) in polymorphonuclear cells obtained from respiratory secretions is a possible method for rapid diagnosis of ventilator-associated pneumonia. We correlated ICOs with quantitative endotracheal aspirate (QA) in intubated patients. METHODS: Consecutive intubated patients in the surgical intensive care unit had respiratory samples obtained every 2 days until extubation. Two thresholds for ICOs and quantitative culture were examined. Sensitivity, specificity, and positive and negative predictive values were calculated using QA as reference. RESULTS: One hundred one samples were obtained from 35 patients. Colony counts >or= 100,000 were found in 34 samples; 60 samples had colony counts >or= 10,000. Antibiotic use did not affect the sensitivity or specificity of ICOs. Sensitivity of ICOs was 39% to 85%, and specificity was 82% to 97%. Positive predictive value was 70% to 96%, and negative predictive value was 50% to 91%. CONCLUSION: ICOs provide a quick method for establishing the presence of a significant bacterial load in the respiratory tract. Accuracy of ICOs in predicting a positive QA is not affected by concurrent antibiotics.
7405.
Bruneel F, Hocqueloux L, Alberti C, Wolff M, Chevret S, Bedos JP, Durand
R, Le Bras J, Regnier B, Vachon F. The
clinical spectrum of severe imported falciparum malaria in the intensive care
unit: report of 188 cases in adults. Am J Respir Crit Care Med. 2003 Mar
1;167(5):684-9.
Little is known about severe imported malaria in nonendemic industrialized countries. The purpose of this retrospective study was to describe the clinical spectrum of severe imported malaria in adults and to determine factors that were present at admission and were associated with in-intensive care unit mortality. This retrospective study evaluated the 188 patients who were admitted to our intensive care unit in 1988-1999 with severe and/or complicated imported malaria. Among them, 93 had strictly defined severe malaria, and 95 had less severe malaria. The mean age was 38 years, 51% of patients were nonimmune whites, 94% acquired Plasmodium falciparum in sub-Saharan Africa, and 96% had taken inadequate antimalarial chemoprophylaxis. Mortality was 11% (10 patients) in the severe malaria group, whereas no patients died in the less severe malaria group (p = 0.002). In the bivariable analysis, the main factors associated with death in the severe malaria group were the Simplified Acute Physiology Score, shock, acidosis, coma, pulmonary edema (p < 0.001 for each), and coagulation disorders (p = 0.002). Bacterial coinfection is not infrequent and may contribute to death. Severe imported malaria remains a major threat to travelers. In our population, the most relevant World Health Organization major defining criteria were coma, shock, pulmonary edema, and acidosis.
7406.
Cherian R, John G, Mahai E, Jeyaseelan L, Kavitha M L, Cherian A M. Risk
factor of noscomial infections in
medical intensive care unit. Indian J Critical Care Med 2001, 5(4), 221-7.
(19710)Vol 38 No 19 1 Oct 2002.
7407.
Westergren V, Bassiri M, Engstrand L.
Bacteria detected by culture and 16S rRNA sequencing in maxillary sinus
samples from intensive care unit patients. Laryngoscope. 2003 Feb;113(2):270-5.
OBJECTIVES/HYPOTHESIS: In critically ill patients, the occurrence of artificial ventilation-acquired sinus disease is common. A possible sinus bacterial infection is occult and is combined with diagnostic difficulties. Culture as a method has limited capacity to verify the presence of bacteria and leaves unanswered the question of a possible infective agent because bacteria are difficult to grow when killed or suppressed by current antibiotic therapy. Hitherto unidentified micro-organisms are also possible in the microenvironments of maxillary sinuses. STUDY DESIGN: Prospective case series. METHODS: Twenty maxillary sinus samples (17 aspirates and 3 lavages) from nine critically ill patients with possible infectious disease were investigated by broad-range 16S rRNA polymerase chain reaction followed by sequencing. These results were compared with the previous culture results from gingiva (passage route), maxillary sinus absorption, and mucosa samples. RESULTS: The contaminations were rare (2 of 20) and corresponded well to culture results. One previously undiagnosed bacterium was found. Two aspirates were negative on both culture and polymerase chain reaction, whereas the corresponding maxillary sinus mucosal cultures had been positive. CONCLUSIONS: Applying a low-contamination maxillary sinuses sampling technique makes 16S rRNA sequencing clinically useful. The polymerase chain reaction and culture results were generally comparable. However, by polymerase chain reaction, bacteria were found that were missed by culturing. Some aspirates were free of bacterial remnants on 16S rRNA polymerase chain reaction, but corresponding mucosal cultures were positive. This could indicate that infection is induced within the tissue. It also indicates that infectious agents introduced into the sinuses may have routes other than the ostium. Further clinical use of 16S rRNA sequencing is required to enlarge our knowledge in applied microbiology and paranasal sinus disease.
7408.
Wu CL, Lee YL, Chang KM, Chang GC, King SL, Chiang CD, Niederman MS.
Bronchoalveolar interleukin-1 beta: a marker of bacterial burden in
mechanically ventilated patients with community-acquired pneumonia. Crit Care
Med. 2003 Mar;31(3):812-7.
OBJECTIVE: To assess the relationship between concentrations of bronchoalveolar cytokines and bacterial burden (quantitative bacterial count) in intubated patients with a presumptive diagnosis of community-acquired pneumonia. DESIGN: A cross-sectional and clinical investigation.SETTING Medical/surgical and respiratory intensive care unit of a tertiary 1,200-bed medical center. PATIENTS: According to the time course of community-acquired pneumonia at the time of study with bronchoalveolar lavage, 69 mechanically ventilated patients were divided into three subgroups: primary (n = 11), referral (n = 23), and treated (n = 35) community-acquired pneumonia. INTERVENTIONS: Bronchoalveolar lavage was performed in the most abnormal area on chest radiograph by fiberoptic bronchoscope. Bronchoalveolar lavage fluid was processed for quantitative bacterial culture. The concentrations of bronchoalveolar lavage cytokines (tumor necrosis factor-alpha, interleukin-1 beta, interleukin-6, interleukin-8, and interleukin-10) also were measured. MEASUREMENTS AND MAIN RESULTS: Thirty- two patients had a positive bacterial culture (bronchoalveolar lavage > or = 10 colony-forming units/mL)., and made up 76% of pathogens recovered at high concentrations. The concentrations of bronchoalveolar lavage interleukin-1 beta were 199.1 +/- 32.1 and 54.9 +/- 13.0 pg/mL (mean +/- se) in the patients with positive and negative bacterial culture, respectively (p < .001). Bronchoalveolar lavage interleukin- 1 beta was significantly higher in the patients with a high bacterial burden (p < .001), with mixed bacterial infection (p < .001), and with pneumonia (p < .001), compared with values in patients without these features. The relationship between bacterial load and concentrations of bronchoalveolar lavage interleukin-1 beta was very strong in the patients with primary and referral community-acquired pneumonia but was borderline in treated community-acquired pneumonia. CONCLUSIONS: The common pathogens were similar to the core pathogens of hospital-acquired pneumonia, probably due to antibiotic effects, delayed sampling, and superimposed nosocomial infection. Since the concentration of bronchoalveolar lavage interleukin-1 beta was correlated with bacterial burden in the alveoli, it may be a marker for progressive and ongoing inflammation in patients who have not responded to pneumonia therapy and who have persistence of bacteria in the lung.
Pathogenesis:
7409.
Gales AC, Tognim MC, Reis AO, Jones RN, Sader HS.
Emergence of an IMP-like metallo-enzyme in an Acinetobacter baumannii
clinical strain from a Brazilian teaching hospital. Diagn Microbiol Infect Dis.
2003 Jan;45(1):77-9.
Multidrug-resistant Acinetobacter spp. constitute a serious cause of nosocomial infection in Brazilian hospitals. This manuscript reports the first appearance of an IMP-like metallo-beta-lactamase encountered in a clinical isolate of A. baumannii from a Brazilian teaching hospital.
7410.
Gonzalez-Reya C, Belin AM, Jorbeck H, Norman M, Krovacek K, Henriques B,
Kallenius G, Svenson SB. RAPD-PCR
and PFGE as tools in the investigation of an outbreak of beta-haemolytic
Streptococcus group A in a Swedish hospital. Comp Immunol Microbiol Infect Dis.
2003 Jan;26(1):25-35.
We evaluated the random amplified polymorphic DNA (RAPD) and pulsed-field gel electrophoresis (PFGE) techniques for studying an outbreak of beta-haemolytic streptococci group A (GAS) occurred at two maternity wards at Danderyd hospital, Stockholm, Sweden. All the isolates were of T-type 8,25. The RAPD technique revealed that all RAPD-PCR profiles were identical. PFGE showed that all the patterns but one were identical. These patterns were compared with 10 different T-type GAS from the strain collection of the Swedish Institute for Infectious Disease Control (SMI) and T-type 8,25 from different years and locations. The SMI strains exhibited patterns different from each other and all different from the isolates from Danderyd hospital. Moreover, RAPD could not differentiate among the T-type 8,25 isolates from different years and locations but PFGE showed differences among the amplicons. Our results indicated that the RAPD and PFGE techniques could be efficient tools in epidemiological studies of GAS.
7411.
Salgado CD, Farr BM, Calfee DP. Community-acquired
methicillin-resistant Staphylococcus aureus: a meta-analysis of prevalence and
risk factors. Clin Infect Dis. 2003 Jan 15;36(2):131-9.
Reports suggest that carriage of methicillin-resistant Staphylococcus aureus (MRSA) among persons without health care-associated risks has increased. A meta-analysis of studies reporting the prevalence of community-acquired MRSA (CA-MRSA) among MRSA isolates from hospitalized patients or the prevalence of MRSA colonization among community members was conducted. The CA-MRSA prevalence among hospital MRSA was 30.2% in 27 retrospective studies and 37.3% in 5 prospective studies; 85% of all patients with CA-MRSA had > or =1 health care-associated risk. The pooled MRSA colonization rate among community members was 1.3% (95% confidence interval [CI], 1.04%-1.53%), but there was significant heterogeneity among study populations. Community members from whom samples were obtained in health care facilities were more likely to be carrying MRSA than were community members from whom samples were obtained outside of the health care setting (relative risk, 2.35; 95% CI, 1.56-3.53). Among studies that excluded persons with health care contacts, the MRSA prevalence was 0.2%. Moreover, most persons with CA-MRSA had > or =1 health care-associated risk, which suggests that the prevalence of MRSA among persons without risks remains low (< or =0.24%). Effective control of dissemination of MRSA throughout the community likely will require effective control of nosocomial MRSA transmission.
Therapy:
7412.
Neely AN, Maley MP, Taylor GL. Investigation
of single-use versus reusable infectious waste containers as potential sources
of microbial contamination. Am J Infect Control. 2003 Feb;31(1):13-7.
BACKGROUND: Laws require that infectious waste be segregated from noninfectious waste. Companies certified to dispose of infectious waste offer both reusable and single-use containers. The focus of this study was to determine if there would be a microbiologic advantage to the use of one type of container over another in a burn hospital. METHODS: Monthly swab cultures were taken from the tops of >250 infectious waste containers during 2 years. Bacteria and fungi were identified. In a substudy swab cultures were taken from an area of reusable tops before and after cleaning to evaluate the efficacy of cleaning on both the number and type of microbes present. Infection rates for acute patients were compared before and after control measures were instituted to decrease microbial transfer from infectious waste containers to patients. RESULTS: Cultures taken from reusable boxes when received from the container company showed that >99% were contaminated with bacteria or fungi; most were normal environmental or skin flora, but some cultures showed microorganisms that can be potentially harmful to patients with compromised immunity. Wiping the lids with a phenolic disinfectant decreased both the total microbial load (P <.001) and the variety of microbes present (P <.001). In contrast, only 10% of the incoming single-use boxes showed any contamination. Infection rates dropped from 5.8 to 3.2 per 100 burn patients (P <.05) after the institution of cleaning and other changes made to decrease the possibility of microbial transfer from the infectious waste boxes to the patients. CONCLUSIONS: Upon delivery, significantly fewer single-use infectious waste boxes were contaminated than reusable ones (P <.001). Extra infection control measures were needed when reusable infectious waste boxes were used in areas housing patients with compromised immunity. Facilities need be aware of the possible contamination of reusable infectious waste containers with microorganisms capable of causing nosocomial infections in patients who are compromised.
7413.
Tekerekoglu MS, Durmaz R, Ayan M, Cizmeci Z, Akinci A.
Analysis of an outbreak due to Chryseobacterium meningosepticum in a
neonatal intensive care unit. New Microbiol. 2003 Jan;26(1):57-63.
The aim of this study was to describe the epidemiological and clinical features
of an outbreak due to Chryseobacterium meningosepticum. During a 11-day period,
the outbreak was observed among four newborns in a neonatal intensive care unit
(NICU) in a teaching hospital. All patients yielded C. meningosepticum in their
blood cultures, in addition one was colonised in the throat. Antimicrobial
susceptibility assay showed complete resistance to penicillins, cephalosporins,
aminoglycosides, imipenem, aztreonam, and tetracycline, sensitivity to
ciprofloxacin and trimethoprim-sulfamethoxazole. All patients were empirically
treated with amikacin and meropenem. The neonate who was the first to develop
sepsis died before the culture result. When C. meningosepticum was identified,
antimicrobial therapy was changed to a combination of ciprofloxacin, rifampicin
and vancomycin, and three neonates were treated successfully. Environmental
screening recovered C. meningosepticum from two venous catheter lines and one
nutritional solution that was opened by health care staff and used for two
neonates. Arbitrary primed polymerase chain reaction and antibiogram typing
indicated that all isolates were epidemiologically related. This study
demonstrates that rapid selection of appropriate antibiotics is critical for
clinical cure and standard precautions should be reconsidered to limit the
spread of this bacterium on the NICU in our hospital.
8097.
Dwosh HA, Hong HH, Austgarden D, Herman S, Schabas R. Identification and
containment of an outbreak of SARS in a community hospital. CMAJ. 2003 May
27;168(11):1415-20.
BACKGROUND:
Severe acute respiratory syndrome (SARS) is continuing to spread around the
world. All hospitals must be prepared to care for patients with SARS. Thus, it
is important to understand the transmission of this disease in hospitals and to
evaluate methods for its containment in health care institutions. We describe
how we cared for the first 2 patients with SARS admitted to our 419-bed
community hospital in Richmond Hill, Ont., and the response to a SARS outbreak
within our institution. METHODS: We collected clinical and epidemiological data
about patients and health care workers at our institution who during a 13-day
period had a potential unprotected exposure to 2 patients whose signs and
symptoms were subsequently identified as meeting the case definition for
probable SARS. The index case at our hospital was a patient who was transferred
to our intensive care unit (ICU) from a referral hospital on Mar. 16, 2003,
where he had been in close proximity to the son of the individual with the first
reported case of SARS in Toronto. After 13 days in the ICU, a diagnosis of
probable SARS was reached for our index case. Immediately upon diagnosis of our
index case, respiratory isolation and barrier precautions were instituted
throughout our hospital and maintained for a period of 10 days, which is the
estimated maximum incubation period reported for this disease. Aggressive
surveillance measures among hospital staff, patients and visitors were also
maintained during this time. RESULTS: During the surveillance period, 15
individuals (10 hospital staff, 3 patients and 2 visitors) were identified as
meeting the case definition for probable or suspected SARS, in addition to our
index case. All but 1 individual had had direct contact with a symptomatic
patient with SARS during the period of unprotected exposure. No additional cases
were identified after infection control precautions had been implemented for 8
days. No cases of secondary transmission were identified in the 21 days
following the implementation of these precautions at our institution.
INTERPRETATION: SARS can easily be spread by direct personal contact in the
hospital setting. We found that the implementation of aggressive infection
control measures is effective in preventing further transmission of this
disease.
8098.
Fisher DA, Lim TK, Lim YT, Singh KS, Tambyah PA. Atypical presentations
of SARS. Lancet. 2003 May 17;361(9370):1740.
No abstract.
8099.
Gunson R, Miller J, Carman WF. Comparison of primers for NLV diagnosis. J
Clin Virol. 2003 Apr;26(3):379-80. No
abstract.
8100.
Lodise TP, McKinnon PS, Swiderski L, Rybak MJ. Outcomes analysis of
delayed antibiotic treatment for hospital-acquired Staphylococcus aureus
bacteremia. Clin Infect Dis. 2003 Jun 1;36(11):1418-23. Epub 2003 May 20.
The
objective of this study was to determine the effect of delayed therapy on
morbidity and mortality associated with nosocomial Staphylococcus aureus
bacteremia.
The study included all episodes of S. aureus bacteremia that developed >2
days after hospital admission during 1999 to 2001. Classification and regression
tree analysis (CART) was used to select the mortality breakpoint between early
and delayed treatment. During the 25-month study period, 167 patients met the
inclusion criteria. The breakpoint between delayed and early treatment derived
using CART was 44.75 hours. On multivariate analysis, delayed treatment was
found to be an independent predictor of infection-related mortality (odds ratio,
3.8; 95% confidence interval, 1.3-11.0; P=.01) and was associated with a longer
hospital stay than was early treatment (20.2 days versus 14.3 days; P=.05).
These findings support the notion that delay of therapy has deleterious effects
on clinical outcomes, and efforts should be made to ensure that appropriate
therapy is initiated promptly.
8101.
Maugein J, Guillemot D, Dupont MJ, Fosse T, Laurans G, Roussel-Delvallez
M, Thierry J, Vergnaud M, Weber M, Poirier B. Clinical and microbiological
epidemiology of Streptococcus pneumoniae bacteremia in eight French counties.
Clin Microbiol Infect. 2003 Apr;9(4):280-8.
OBJECTIVE:
To describe the incidence of pneumococcal bacteremia not associated with
infection of the central nervous system, investigate the susceptibility of
bacterial isolates to beta-lactams, evaluate risk factors for antibiotic
resistance, and determine factors predicting patient outcome. METHODS: Over a
period of 1 year, 919 Streptococcus pneumoniae isolates were collected from 919
patients with bacteremia in eight French counties. Their clinical and
microbiological features were recorded. Univariate and multivariate analyses
were used to determine risk factors for penicillin-non-susceptible pneumococcal
bacteremia and predictors of fatal outcome. RESULTS: Of the 919 patients in the
study, 27% were infected with penicillin-non-susceptible pneumococci (PNSP):
17.8% of the isolates were intermediate to penicillin, 7.2% were resistant to
penicillin, 16% were intermediate to amoxicillin, and 11% were intermediate to
cefotaxime; no PNSP were resistant to either of the last two antibiotics. The
most common PNSP serotypes isolated were 14 (41%) and 23 (24%). A statistically
significant relationship between PNSP infection and age below 5 years or above
60 years in the different counties was observed by univariate and multivariate
analysis. Gender, origin of bacteremia, co-morbidity, immunodeficiency, previous
hospitalization and nosocomial infection were not predisposing factors
associated with PNSP. The mortality rate was 20.6%: there was no increase in
mortality among patients with PNSP bacteremia. Age was the strongest risk factor
for mortality, but immunodeficiency also seemed to have had an impact on
mortality. Clinical outcome was more closely related to clinical conditions than
to the susceptibility status of S. pneumoniae. CONCLUSION: Among cases of
bacteremia, 27% were caused by PNSP, but this level varies according to the
counties and the age of the patients. Infection-related mortality was high, but
there was no increase related to penicillin G non-susceptibility of the
infecting
strain.
8102.
Mitchell S, O'Neill HJ, Ong GM, Christie S, Duprex P, Wyatt DE, McCaughey
C, Armstrong VJ, Feeney S, Metwally L, Coyle PV. Clinical assessment of a
generic DNA amplification assay for the identification of respiratory adenovirus
infections. J Clin Virol. 2003 Apr;26(3):331-8.
BACKGROUND:
respiratory adenoviruses are common, often resulting in serious sporadic and
epidemic infections and impaired immunity can dramatically increase their
severity. They are now thought capable of establishing latency. Diagnosis by
culture is slow while direct antigen detection by immunofluorescence lacks
sensitivity. Molecular diagnosis can be both rapid and sensitive but the genetic
heterogeneity of adenoviruses poses problems. OBJECTIVES: to design a generic
adenovirus nested polymerase chain amplification assay designed to be capable of
detecting all respiratory adenoviruses. This was achieved through optimised
thermal cycling and the development of a generic degenerate primer set targeting
the adenovirus hexon gene. STUDY DESIGN: this was a cross-sectional study on 172
respiratory specimens from hospital-based patients, and one from a general
practice, in Northern Ireland. A comparison was made between the amplification
assay, virus culture and immunofluorescence. RESULTS: the nested polymerase
chain reaction (nPCR) assay had a generic capacity for adenovirus detection and
an analytical sensitivity of 6.4x10(2) copies/ml. Using an expanded gold
standard (defined as a true positive or a true negative where a specimen was
positive or negative by at least two of the study assays, respectively), PCR had
a clinical sensitivity and specificity of 46/46 (100%) and 15/126 (91.3%),
respectively. Patients with acute respiratory adenovirus infections were more
likely to be male (chi(2), p=0.005) and to present with a fever (chi(2), p=0.02)
than patients diagnosed with another respiratory virus. Co-infection was
identified in 12/172 patients. CONCLUSIONS: the nested amplification assay
proved highly sensitive in both the analytical and clinical settings for the
detection of respiratory adenovirus infections.
Pathogenesis:
8103. Esper F, Boucher D, Weibel C, Martinello RA, Kahn JS. Human metapneumovirus infection in the United States: clinical manifestations associated with a newly emerging respiratory infection in children. Pediatrics. 2003 Jun;111(6 Pt 1):1407-10.
OBJECTIVE:
Respiratory tract infections are a leading cause of morbidity and mortality
worldwide. Recently, a newly identified human respiratory virus, human
metapneumovirus (hMPV), was reported by investigators in the Netherlands. We
sought to determine whether hMPV was circulating in our community and to
determine the clinical features associated with hMPV infection. METHODS:
Respiratory specimens from children who were younger than 5 years and had a
negative result for respiratory syncytial virus, influenza A and B,
parainfluenza viruses 1 to 3, and adenovirus by direct fluorescent antibody test
were screened for hMPV by reverse transcriptase-polymerase chain reaction.
Samples were collected from October 30, 2001, to February 28, 2002. RESULTS: Of
the 296 patients screened, 19 (6.4%) had evidence of hMPV infection. hMPV was
identified in patients with either upper or lower respiratory tract infection or
both. Clinical manifestations included wheezing, hypoxia, and abnormal findings
on chest radiographs (eg, focal infiltrates, peribronchial cuffing). Nosocomial
infection occurred in at least 1 patient. CONCLUSIONS: hMPV is circulating in
the United States and is associated with respiratory tract disease in patients
with respiratory illnesses not caused by respiratory syncytial virus, influenza,
parainfluenza viruses, and adenovirus. Additional studies are required to define
the epidemiology and the extent of disease in the general population caused by
hMPV.
8104. Harrison WA, Griffith CJ, Michaels B, Ayers T. Technique to determine contamination exposure routes and the economic efficiency of folded paper-towel dispensing. Am J Infect Control. 2003 Apr;31(2):104-8.
Handwashing
and hand drying are key elements of infection control. Paper towels are
generally accepted as the most hygienic means of drying hands and are often
distributed from generic dispensers. Effective dispensing of towels is of
importance economically and may influence infection control objectives if hands
become contaminated during hand drying. In this study, a method to identify
potential exposure routes for hand contamination and evaluate the efficiency of
paper-towel dispensing is described and applied to 5 different folded paper
towels using a generic wall-mounted dispenser. A total of 18 male and female
participants of varying heights participated in pull testing of 400 paper towels
each, in controlled hand-drying simulations. All events having the potential for
hand contamination, including towel jamming, towels falling onto the floor, and
incidental contact of paper exits, were monitored and documented. There was
considerable variation in dispensing efficiency between different towel brands.
One towel (Z) had significantly (P <.05) superior dispensing properties from
the generic dispenser. Participants of a shorter height obtained a lower
incidence of dispensing malfunctions using all towel products and type. The
results indicated likely contamination exposure routes and wastage levels for
each towel type. Environmental service managers and infection control
practitioners should carefully consider, for economic and infection control
reasons, the siting and design of towel dispensers and the types of towel
purchased.
8105. Mitchell S, O'Neill HJ, Ong GM, Christie S, Duprex P, Wyatt DE, McCaughey C, Armstrong VJ, Feeney S, Metwally L, Coyle PV. Clinical assessment of a generic DNA amplification assay for the identification of respiratory adenovirus infections. J Clin Virol. 2003 Apr;26(3):331-8.
BACKGROUND:
respiratory adenoviruses are common, often resulting in serious sporadic and
epidemic infections and impaired immunity can dramatically increase their
severity. They are now thought capable of establishing latency. Diagnosis by
culture is slow while direct antigen detection by immunofluorescence lacks
sensitivity. Molecular diagnosis can be both rapid and sensitive but the genetic
heterogeneity of adenoviruses poses problems. OBJECTIVES: to design a generic
adenovirus nested polymerase chain amplification assay designed to be capable of
detecting all respiratory adenoviruses. This was achieved through optimised
thermal cycling and the development of a generic degenerate primer set targeting
the adenovirus hexon gene. STUDY DESIGN: this was a cross-sectional study on 172
respiratory specimens from hospital-based patients, and one from a general
practice, in Northern Ireland. A comparison was made between the amplification
assay, virus culture and immunofluorescence. RESULTS: the nested polymerase
chain reaction (nPCR) assay had a generic capacity for adenovirus detection and
an analytical sensitivity of 6.4x10(2) copies/ml. Using an expanded gold
standard (defined as a true positive or a true negative where a specimen was
positive or negative by at least two of the study assays, respectively), PCR had
a clinical sensitivity and specificity of 46/46 (100%) and 15/126 (91.3%),
respectively. Patients with acute respiratory adenovirus infections were more
likely to be male (chi(2), p=0.005) and to present with a fever (chi(2), p=0.02)
than patients diagnosed with another respiratory virus. Co-infection was
identified in 12/172 patients. CONCLUSIONS: the nested amplification assay
proved highly sensitive in both the analytical and clinical settings for the
detection of respiratory adenovirus infections.
8106. Mondino PJ, Dos Santos KR, de Freire Bastos Mdo C, Giambiagi-deMarval M. Improvement of mupirocin E-test for susceptibility testing of Staphylococcus aureus. J Med Microbiol. 2003 May;52(Pt 5):385-7.
Interpretation
of the mupirocin E-test for low-level mupirocin-resistant Staphylococcus aureus
strains has been improved by adding the indicator dye tetrazolium. E-tests were
compared with agar dilution methods for assessing mupirocin susceptibility. MICs
obtained by the agar dilution method and E tests showed 89.3% agreement within 2
log(2) dilution criteria. The agreement between MICs increased to 100% in the 1
log(2) dilution definition when the indicator dye tetrazolium was added to the
E-test. The use of the E-test with tetrazolium reduction is more accurate for
determining mupirocin MICs for S. aureus strains.
Therapy:
8107.
Fridkin SK. Routine cycling of antimicrobial agents as an
infection-control measure. Clin Infect Dis. 2003 Jun 1;36(11):1438-44. Epub 2003
May 20.
Antimicrobial cycling is the deliberate, scheduled removal and substitution of specific antimicrobials or classes of antimicrobials within an institutional environment (either hospital-wide or confined to specific units) to avoid or reverse the development of antimicrobial resistance. True antimicrobial cycling requires a return to the antimicrobial(s) that were first used. Testing of the hypothesis that cycling will result in a lower prevalence of resistance is ongoing, mostly occurs within intensive care units, and largely involves cycling regimens targeted for treatment of suspected gram-negative bacterial infections. Unfortunately, there has been insufficient study to determine whether any meaningful impact on resistance has occurred as a result of a cycling program. Mathematical models question the usefulness of cycling as an infection-control method. Published studies demonstrate that cycling may be one way to change prescribing practices by clinicians without sacrificing patient safety. However, optimizing antimicrobial use through traditional and novel methods (e.g., computer decision support) should not be abandoned.