Some selected abstract:

1

Cavalcante SS, Mota E, Silva LR, Teixeira LF, Cavalcante LB. Risk factors for developing nosocomial infections among pediatric patients. Pediatr Infect Dis J. 2006 May;25(5):438-45.

Department of Pediatrics, Federal University of Bahia, Brazil. suzy_sc@terra.com.br

BACKGROUND: Nosocomial infections (NIs) are important causes of morbidity and mortality in pediatric hospitals. Multiple factors contribute towards exposing children to the risk of infection when hospitalized, and some of them differ from those in adults. METHODS: This was a prospective study in a tertiary-level teaching pediatric hospital in Salvador, Bahia, Brazil, conducted from January to July, 2003, to describe the epidemiologic characteristics of NIs. Centers for Disease Control's standard definitions were used and the data recorded included intrinsic and extrinsic risk factors. RESULTS: We evaluated 808 patients. There were 143 episodes of NI in 124 patients (15.4%). The overall incidence of NI cases was 9.2 per 1,000 patient-days, with higher rates among children aged less than 1 year (P < 0.001) and those with nonsurgical clinical diseases (P < 0.001). Gastrointestinal infections (39.2%) and eye, ear, nose, throat or mouth infections (29.4%) were most common. The factors most closely associated with higher incidence of NI were respiratory disease on admission (incidence density ratio [IDR], 4.0; 95% confidence interval [CI], 2.83-5.72), another disease associated with admission diagnosis (IDR, 3.5; 95% CI, 2.41-5.02), nonsurgical clinical disease (IDR, 5.9; 95% CI, 3.92-8.85) and pediatric intensive care unit residence (IDR, 3.5; 95% CI, 1.91-6.28). The lengths of hospital stay for patients with and without nosocomial infection were, respectively, 14.1 days (SD, 20.5 days) and 5.1 days (SD, 6.6 days) (t = 121.76; P < 0.001). CONCLUSIONS: Nosocomial infections are a frequent complication in pediatrics. They are not necessarily related to invasive procedures but certainly are related to a group of factors that have particular characteristics in the pediatric age group.
 

Church D, Elsayed S, Reid O, Winston B, Lindsay R.Burn wound infections.  Clin Microbiol Rev. 2006 Apr;19(2):403-34.

Calgary Laboratory Services, 9-3535 Research Rd. N.W., Calgary, Alberta, Canada T2L 2K8. Deirdre.church@cls.ab.ca

Burns are one of the most common and devastating forms of trauma. Patients with serious thermal injury require immediate specialized care in order to minimize morbidity and mortality. Significant thermal injuries induce a state of immunosuppression that predisposes burn patients to infectious complications. A current summary of the classifications of burn wound infections, including their diagnosis, treatment, and prevention, is given. Early excision of the eschar has substantially decreased the incidence of invasive burn wound infection and secondary sepsis, but most deaths in severely burn-injured patients are still due to burn wound sepsis or complications due to inhalation injury. Burn patients are also at risk for developing sepsis secondary to pneumonia, catheter-related infections, and suppurative thrombophlebitis. The introduction of silver-impregnated devices (e.g., central lines and Foley urinary catheters) may reduce the incidence of nosocomial infections due to prolonged placement of these devices. Improved outcomes for severely burned patients have been attributed to medical advances in fluid resuscitation, nutritional support, pulmonary and burn wound care, and infection control practices.
 

Depuydt P, Myny D, Blot S. Nosocomial pneumonia: aetiology, diagnosis and treatment. Curr Opin Pulm Med. 2006 May;12(3):192-7.

Department of Intensive Care, Ghent University, De Pintelaan, Belgium. pieter.depuydt@ugent.be

PURPOSE OF REVIEW: This review highlights recent advances in the aetiology of nosocomial pneumonia, and in strategies to increase accuracy of diagnosis and antibiotic prescription while limiting unnecessary antibiotic consumption. RECENT FINDINGS: Bacterial pathogens still cause the bulk of nosocomial pneumonia and are of concern because of ever-rising antimicrobial resistance. Yet, the pathogenic role of fungal and viral organisms is increasingly recognized. Since early appropriate antimicrobial therapy is the cornerstone of an effective treatment, further studies have been conducted to improve appropriateness of early antibiotic therapy. De-escalation strategies combine initial broad-spectrum antibiotics to maximize early antibiotic coverage with a subsequent focusing of the antibiotic spectrum when the cause is identified. Invasive techniques probably do not alter the immediate outcome but have the potential to reduce unnecessary antibiotic exposure. Decisions to stop or change antibiotic therapy are hampered due to a lack of reliable parameters to assess the resolution of pneumonia. SUMMARY: Increasing antimicrobial resistance in nosocomial pneumonia both challenges treatment and mandates limitation of selection pressure by reducing antibiotic burden. Treating physicians should be both aggressive in initiating antimicrobials when suspecting nosocomial pneumonia but willing to discontinue antimicrobials when diagnostic results point to an alternative diagnosis. Efforts should be made to limit duration of antibiotic therapy when possible.
 

Miller PR, Partrick MS, Hoth JJ, Meredith JW, Chang MC.  A practical application of practice-based learning: development of an algorithm for empiric antibiotic coverage in ventilator-associated pneumonia. J Trauma. 2006 Apr;60(4):725-9; discussion 729-31.

Department of Surgery, Wake Forest University Bowman Gray School of Medicine, Winston-Salem, NC 27157, USA. pmiller@wfubmc.edu

BACKGROUND: Development of practice-based learning (PBL) is one of the core competencies required for resident education by the Accreditation Council for Graduate Medical Education, and specialty organizations including the American College of Surgeons have formed task forces to understand and disseminate information on this important concept. However, translating this concept into daily practice may be difficult. Our goal was to describe the successful application of PBL to patient care improvement with development of an algorithm for the empiric therapy of ventilator-associated pneumonia (VAP). METHODS: The algorithm development occurred in two phases. In phase 1, the microbiology and timing of VAP as diagnosed by bronchoalveolar lavage was reviewed over a 2-year period to allow for recognition of patterns of infection. In phase 2, based on these data, an algorithm for empiric antibiotic coverage that would ensure that the large majority of patients with VAP received adequate initial empiric therapy was developed and put into practice. The period of algorithm use was then examined to determine rate of adequate coverage and outcome. RESULTS:: In Phase 1, from January 1, 2000 to December 31 2001, 110 patients were diagnosed with VAP. Analysis of microbiology revealed a sharp increase in the recovery of nosocomial pathogens on postinjury day 7 (19% < day 7 versus 47% > or = day 7, p = 0.003). Adequate initial antibiotic coverage was seen in 74%. In Phase 2, an algorithm employing ampicillin- sulbactam for coverage of community- acquired pathogens before day 7 and cefipime for nosocomial coverage > or =day 7 was then employed from January 1, 2024 to December 31, 2003. Evaluation of 186 VAP cases during this interval revealed a similar distribution of nosocomial cases (13% < day 7 versus 64% > or = day 7, p < 0.0001). Empiric antibiotic therapy was adequate in 82% of cases <day 7 and 85% of cases > or =day 7: overall accuracy improved to 83% (p = 0.05). Mortality from phase 1 to phase 2 trended toward a decrease (21% versus 13%, p = 0.1). CONCLUSIONS: Application of the concept of PBL allowed for identification of local patterns of infection and development of an institution specific treatment algorithm that resulted in >80% adequate initial empiric coverage for VAP with a trend toward decreased mortality. PBL allows for alteration in practice based on local patterns and outcomes and has the potential to improve patient care.
 

Ramphal R, Ambrose PG. Extended-spectrum beta-lactamases and clinical outcomes: current data. Clin Infect Dis. 2006 Apr 15;42 Suppl 4:S164-72.

Department of Medicine, University of Florida Health Sciences Center, Gainesville, FL 32610, USA. ramphr@medmac.ufl.edu

Nosocomial infections caused by extended-spectrum beta-lactamase (ESBL)-producing gram-negative bacteria complicate therapy and limit treatment options. However, the clinical significance of infections caused by ESBL-producing bacteria remains unclear. A critical examination of the literature provides divergent views of the effect of ESBL carriage on morbidity and mortality and suggests that ESBL production may have its most marked effect on ceftazidime. Effective strategies for the empirical and directed treatment of infections caused by ESBL-producing pathogens include the use of carbapenems and, possibly, the fourth-generation cephalosporin cefepime. Studies indicate that the use of cefepime to treat serious nosocomial infections (e.g., bacteremia, pneumonia, and urinary tract infections) is associated with high rates of microbiological and clinical success. The probability of attaining time above the minimum inhibitory concentration targets of at least 70% of the dosing interval, an important pharmacodynamic indicator of clinical success, is higher with cefepime than with other antimicrobials against Escherichia coli and Klebsiella pneumoniae strains exhibiting ESBL phenotypes. However, for non-ESBL-producing strains, there is no difference in the time above the minimum inhibitory concentration between ceftazidime and cefepime. When used appropriately in institutional settings, cefepime reduces the overall use of cephalosporins, thereby decreasing selection pressure for presumptive ESBL-producing pathogens.

Wong GK, Chan MT, Boet R, Poon WS, Gin T. Intravenous magnesium sulfate after aneurysmal subarachnoid hemorrhage: a prospective randomized pilot study. J Neurosurg Anesthesiol. 2006 Apr;18(2):142-8.

Division of Neurosurgery, Department of Surgery, Prince of Wales Hospital, Chinese University of Hong Kong, Shatin, Hong Kong Special Administrative Region.

We performed a randomized, double-blind, pilot study on magnesium sulfate (MgSO4) infusion for aneurysmal subarachnoid hemorrhage (SAH).Sixty patients with SAH were randomly allocated to receive either MgSO4 80 mmol/day or saline infusion for 14 days. Patients also received intravenous nimodipine. Episodes of vasospasm were treated with hypertensive and hypervolemic therapy. Neurologic status was assessed 6 months after hemorrhage using the Barthel index and Glasgow Outcome Scale. Incidences of cardiac and pulmonary complications were also recorded.Patient characteristics, severity of SAH, and surgical treatment did not differ between groups. The incidence of symptomatic vasospasm decreased from 43% in the saline group to 23% in patients receiving MgSO4 infusion, but it did not reach statistical significance, P=0.06. For patients who had transcranial Doppler-detected vasospasm, defined as mean flow velocity >120 cm/s and a Lindegaard index >3, the duration was shorter in the magnesium group compared with controls (P<0.01). There was, however, no difference between groups in functional recovery or Glasgow Outcome Scale score. The incidence of adverse events such as brain swelling, hydrocephalus, and nosocomial infection was also similar in patients receiving MgSO4 or saline.In this small pilot study, MgSO4 infusion for aneurysmal SAH is feasible. On the basis of the preliminary data, a larger study recruiting approximately 800 patients is required to test for a possible neuroprotective effect of magnesium after SAH.
 

Diagnosis, Diagnostics, Immunodiagnosis & Immunodiagnostics:

14786.  Anderson DJ, Engemann JJ, Harrell LJ, Carmeli Y, Reller LB, Kaye KS. Predictors of mortality in patients with bloodstream infection due to ceftazidime-resistant Klebsiella pneumoniae. Antimicrob Agents Chemother. 2006 May;50(5):1715-20.

14787.  Arya SC, Agarwal N, Agarwal S. A laboratory-based, hospital-wide, electronic marker for nosocomial infection. Am J Clin Pathol. 2006 Jun;125(6):954.

14788.  Bootsma MC, Diekmann O, Bonten MJ. Controlling methicillin-resistant Staphylococcus aureus: quantifying the effects of interventions and rapid diagnostic testing. Proc Natl Acad Sci U S A. 2006 Apr 4;103(14):5620-5.

Therapy:

14789.  Fridkin SK, Kaufman D, Edwards JR, Shetty S, Horan T. Changing incidence of Candida bloodstream infections among NICU patients in the United States: 995-2004. Pediatrics. 2006 May;117(5):1680-7.

14790.  Livermore DM. Can beta-lactams be re-engineered to beat MRSA? Clin Microbiol Infect. 2006 Apr;12 Suppl 2:11-6.

14791.  Sanchez-Velazquez LD, Ponce de Leon Rosales S, Rangel Frausto MS. The burden of nosocomial infection in the intensive care unit: Effects on organ failure, mortality and costs. A nested case-control study. Arch Med Res. 2006 Apr;37(3):370-5.