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3619.               Aghanwa HS.  Morakinyo O. Correlates of psychiatric morbidity in typhoid fever in a Nigerian general hospital setting. General Hospital Psychiatry.  23(3):158-62, 2001 May-Jun.


  This study explored factors associated with psychiatric morbidity in typhoid fever in a Nigerian general hospital. Information such as sociodemographic characteristics, symptom manifestations, results of investigations, neuropsychiatric symptoms, outcome and disposal were obtained from the case files of patients admitted for typhoid fever over a period of six years. The patients with psychiatric morbidity conspicuous enough to be documented by the attending physicians-mostly internists-were compared with those with no documented psychiatric morbidity on sociodemographic and clinical indices. Of the 136 cases, 26 (19.1%) had psychiatric morbidity. This included delirium (73.1%), generalized anxiety disorder (3.8%), depressive episode (3.8%), schizophrenia like disorder (3.8%) and monosymptomatic neuropychiatric manifestations such as apathy, hallucinations and irrelevant talking (15.5%). The clinical and sociodemographic indices that were significantly associated with psychiatric morbidity were diarrhea, blood biochemical imbalance and age (P<.05). Adolescents and young adults were more predisposed to developing psychiatric complications. Some factors potentially associated with psychiatric morbidity in typhoid fever have been identified. There is the need to prospectively assess the burden from psychiatric morbidity and identify interventions that may reduce it.

3620.               Choo KE.  Davis TM.  Henry RL.  Chan LP. Serum C-reactive protein concentrations in Malaysian children with enteric fever.  Journal of Tropical Pediatrics.  47(4):211-4, 2001 Aug.


  To explain good clinical results of azithromycin in patients with typhoid fever, 10 strains of Salmonella typhi were grown in cation-adjusted Mueller-Hinton broth. MICs of azithromycin were 4-16 mg/L. At a sub-MIC of 2 mg/L, early inhibition of growth was shown at 2, 4 and 8 h of incubation, but at 24 and 48 h growth to turbidity occurred. At 4 mg/L, inhibition occurred up to 8 h, after which growth towards turbidity followed. Elongated curved bacilli formed in broth containing 4 mg/L after 24-48 h. Adjusting the pH of the broth with phosphate-citrate buffer to 7.5 and 8.0 caused reductions in MICs to 0.25-0.5 mg/L. Large inocula of 10(6) cfu/mL resulted in median MICs four- to six-fold greater than with inocula of 10(1)-10(3) cfu/mL. An inoculum of 10 bacteria per mL in broth at pH 7.5 resulted in an MIC of 0.13 mg/L. Clinical benefits in patients may occur because of early inhibition by sub-MIC concentrations of azithromycin, and due to lower MICs at alkaline pH and lower MICs with small inocula that may correspond to the low-grade bacteraemia in typhoid fever.

3621.               Dutta P.  Mitra U.  Datta S.  Saha MR.  De A.  Roy K.  Basak M.  Bhattacharya SK. Ciprofloxacin susceptible Salmonella typhi with treatment failure.  Journal of Tropical Pediatrics.  47(4):252-3, 2001 Aug.

3622.               House D.  Wain J.  Ho VA.  Diep TS.  Chinh NT.  Bay PV.  Vinh H.  Duc M.  Parry CM.  Dougan G.  White NJ.  Hien TT.  Farrar JJ. Serology of typhoid fever in an area of endemicity and its relevance to diagnosis. Journal of Clinical Microbiology.  39(3):1002-7, 2001 Mar.


  Currently, the laboratory diagnosis of typhoid fever is dependent upon either the isolation of Salmonella enterica subsp. enterica serotype Typhi from a clinical sample or the detection of raised titers of agglutinating serum antibodies against the lipopolysaccharide (LPS) (O) or flagellum (H) antigens of serotype Typhi (the Widal test). In this study, the serum antibody responses to the LPS and flagellum antigens of serotype Typhi were investigated with individuals from a region of Vietnam in which typhoid is endemic, and their usefulness for the diagnosis of typhoid fever was evaluated. The antibody responses to both antigens were highly variable among individuals infected with serotype Typhi, and elevated antibody titers were also detected in a high proportion of serum samples from healthy subjects from the community. In-house enzyme-linked immunosorbent assays (ELISAs) for the detection of specific classes of anti-LPS and antiflagellum antibodies were compared with other serologically based tests for the diagnosis of typhoid fever (Widal TO and TH, anti-serotype Typhi immunoglobulin M [IgM] dipstick, and IDeaL TUBEX). At a specificity of > or =0.93, the sensitivities of the different tests were 0.75, 0.55, and 0.52 for the anti-LPS IgM, IgG, and IgA ELISAs, respectively; 0.28 for the antiflagellum IgG ELISA; 0.47 and 0.32 for the Widal TO and TH tests, respectively; and 0.77 for the anti-serotype Typhi IgM dipstick assay. The specificity of the IDeaL TUBEX was below 0.90 (sensitivity, 0.87; specificity, 0.76). The serological assays based on the detection of IgM antibodies against either serotype Typhi LPS (ELISA) or whole bacteria (dipstick) had a significantly higher sensitivity than the Widal TO test when used with a single acute-phase serum sample (P < or = 0.007). These tests could be of use for the diagnosis of typhoid fever in patients who have clinical typhoid fever but are culture negative or in regions where bacterial culturing facilities are not available.

3623.               Koul PA. A Salmonella typhi Vi conjugate vaccine. New England Journal of Medicine.  345(7):545-6, 2001 Aug 16. No Abstract.

3624.               Rajeev A. Quinolone resistant typhoid outbreak in an extended joint family. J Commun. Dis. 31(4):23-5,1999. No Abstract.


3625.               Uysal H.  Karademir A.  Kilinc M.  Erturk O. Salmonella encephalopathy with seizure and frontal intermittent rhythmic delta activity.  Infection.  29(2):103-6, 2001 Mar-Apr.


  A 54-year-old woman was admitted to our clinic with frequent convulsions. Subsequently she developed a toxic look, rigidity, confusion and severe encephalopathy. Salmonella typhii was isolated from the blood cultures and she was diagnosed with Salmonella encephalopathy. The prominent electrophysiological finding was the frontal intermittent rhythmic delta activity (FIRDA) in electroencephalograph (EEG). After treatment EEG revealed normal activity. The presence of FIRDA is not a specific finding but this kind of EEG change has not been reported before. Diffuse encephalopathy due to endotoxins might be the reason. We propose that S. typhii encephalopathy was the cause of FIRDA which is a sign of diffuse encephalopathy.

3626.               Wain J.  Pham VB.  Ha V.  Nguyen NM.  To SD.  Walsh AL.  Parry CM.  Hasserjian RP.  HoHo VA.  Tran TH.  Farrar J.  White NJ.  Day NP. Quantitation of bacteria in bone marrow from patients with typhoid fever: relationship between counts and clinical features. Journal of Clinical Microbiology.  39(4):1571-6, 2001 Apr.


  Enteric fever is the only bacterial infection of humans for which bone marrow examination is routinely recommended. A prospective study of the concentrations of bacteria in the bone marrow and their relationship to clinical features was conducted with 120 Vietnamese patients with suspected enteric fever, of whom 89 had confirmed typhoid fever. Ninety-three percent of the Salmonella enterica serovar Typhi samples isolated were resistant to ampicillin, chloramphenicol, and co-trimoxazole. For 81 patients with uncomplicated typhoid and satisfactory bone marrow aspirates, the number of serovar Typhi CFU in bone marrow aspirates was a median value of 9 (interquartile range [IQR], 1 to 85; range, 0.1 to 1,580) compared to 0.3 (IQR, 0.1 to 10; range, 0.1 to 399) CFU/ml in simultaneously sampled blood. The ratio of individual blood counts to bone marrow counts was 10 (IQR, 2.3 to 97.5). The number of bacteria in blood but not bone marrow was correlated inversely with the duration of preceding fever. Thus, with increasing duration of illness the ratio of bone marrow-to-blood bacterial concentrations increased; the median ratio was 4.8 (IQR, 1 to 27.5) during the first week compared with 158 (IQR, 60 to 397) during the third week. After lysing the host cells, the median ratio of viable bone marrow to blood increased, reflecting the higher concentration of intracellular serovar Typhi in the bone marrow. Effective antibiotic pretreatment had a significantly greater effect in reducing blood counts compared to bone marrow counts (P < 0.001). Thus, bacteria in the bone marrow of typhoid patients are less affected by antibiotic treatment than bacteria in the blood. The numbers of bacteria in bone marrow correlated negatively with the white blood cell (R = -0.3, P = 0.006) and platelet counts (R = -0.32, P = 0.01) and positively with fever clearance time after treatment (R = 0.4, P < 0.001). The bacterial load in bone marrow therefore may reflect the clinical course of the infection, and high levels may suppress neutrophil proliferation.

3627.               Walker AR. Changes in public health in South Africa from 1876. Journal of the Royal Society of Health.  121(2):85-93, 2001 Jun.


  The present population in South Africa, roughly 43 million inhabitants, is made up of Africans (77.2%), whites (10.5%), Coloureds (mixed race) (8.8%) and Indians (2.5%). In 1900 the infant mortality rate (IMR) among Africans was 330 per 1,000 live births; this has now fallen to 50-60. In Soweto, a primarily African city, IMR averages 20-25. Life expectancy in the past was only 25-30 years; by 1995, this reached 63 years. However, this could fall again due to the rapidly spreading HIV/AIDS epidemic. Life expectancy could fall to 40-45 years by 2010 with the AIDS epidemic being the cause of half of all deaths--a disastrous change from the previous relatively commendable public health situation. Formerly, the most common causes of deaths in young people were infections, diseases associated with malnutrition and gastroenteritis. Adults died almost solely from infections, including typhoid, dysentery, malaria and tuberculosis (TB). Even though diseases associated with malnutrition are less common today, many infections still remain a major problem, particularly TB, which is increasing. As late as 1970, Africans who reached 50 years had longer life expectancy than whites due to the low prevalences of the chronic diseases of lifestyle. This is no longer so, due to the recent rises in non-communicable disorders/diseases, principally obesity in women, hypertension, diabetes, stroke and the cancers of prosperity. In the not so distant future, the level of control of HIV/AIDS related diseases will be the major health/disease regulating factor among Africans. Among white, Coloured and Indian populations, there have been falls in the mortality rates of the young and, despite rises in lifestyle diseases, increases in life expectancy are continuing. For all populations other important public health regulatory factors include water supply, sanitation, clinic/hospital services and personal environmental factors, employment, dietary pattern and intake, smoking practices and alcohol consumption and physical activity, particularly in urban dwellers. Unfortunately, public health expenditure, also a highly regulating factor, has fallen from 8.2% of the gross domestic product in 1994 to 4.1% in 2000.

3628.               Woo PC.  Fung AM.  Wong SS.  Tsoi HW.  Yuen KY. Isolation and characterization of a Salmonella enterica serotype Typhi variant and its clinical and public health implications. Journal of Clinical Microbiology.  39(3):1190-4, 2001 Mar.


  We report the isolation and characterization of a member of the family Enterobacteriaceae isolated from the gallbladder pus of a food handler. Conventional biochemical tests suggested Salmonella enterica serotype Typhi, but the isolate agglutinated with poly(O), 2O, 9O, and Vi Salmonella antisera but not with poly(H) or any individual H Salmonella antisera. 16S rRNA gene sequencing showed that there were two base differences between the isolate and Salmonella enterica serotype Montevideo, four base differences between the isolate and serotype Typhi, five base differences between the isolate and Salmonella enterica serotype Typhimurium, and six base differences between the isolate and Salmonella enterica serotype Dublin, indicating that the isolate was a strain of S. enterica. Electron microscopy confirmed that the isolate was aflagellated. The flagellin gene sequence of the isolate was 100% identical to that of the H1-d flagellin gene of serotype Typhi. Sequencing of the rfbE gene, which encoded the CDP-tyvelose epimerase of the isolate, showed that there was a point mutation at position +694 (G-->T), leading to an amino acid substitution (Gly-->Cys). This may have resulted in a protein of reduced catalytic activity and hence the presence of both 2O and 9O antigens. We therefore concluded that the isolate was a variant of serotype Typhi. Besides antibiotic therapy and cholecystectomy, removal of all stones in the biliary tree was performed for eradication of the carrier state.

Apr 02

4357.               Kutteh WH, Kantele A, Moldoveanu Z, Crowley-Nowick PA, Mestecky J. Induction of specific immune responses in the genital tract of women after oral or rectal immunization and rectal boosting with Salmonella typhi Ty 21a vaccine. J Reprod Immunol  2001 Oct-Nov;52(1-2):61-75


The purpose of this study was to determine the efficacy of intestinal tract immunization in the induction of specific antibodies in human female genital tract secretions. Live attenuated typhoid vaccine Ty 21a was administered to three groups of healthy female volunteers, who were not using hormonal contraceptives. Group 1 included 15 women vaccinated orally. Group 2 included seven of the same women, who were vaccinated rectally 6 months later. Group 3 included 11 volunteers, who were vaccinated rectally. Salmonella-specific antibodies of IgG and IgA were measured in vaginal lavage and cervical mucus after oral or rectal primary vaccination. Salmonella-specific antibodies measured 1 month after rectal booster vaccination demonstrated significant increases in vaginal fluids and cervical mucus and were dominated by IgA. These results indicate that specific antibodies in the human female genital tract induced by primary vaccination can be enhanced by subsequent rectal administration of vaccines.


4358.               Larsen TS, Leather S, Moule S, O'Gaora P, Parry C, Quail M, Rutherford K, Simmonds M, Skelton J, Stevens K, Whitehead S, Barrell BG. Complete genome sequence of a multiple drug resistant Salmonella enterica serovar Typhi CT18. Nature  2001 Oct 25;413(6858):848-52


Salmonella enterica serovar Typhi (S. typhi) is the aetiological agent of typhoid fever, a serious invasive bacterial disease of humans with an annual global burden of approximately 16 million cases, leading to 600,000 fatalities. Many S. enterica serovars actively invade the mucosal surface of the intestine but are normally contained in healthy individuals by the local immune defence mechanisms. However, S. typhi has evolved the ability to spread to the deeper tissues of humans, including liver, spleen and bone marrow. Here we have sequenced the 4,809,037-base pair (bp) genome of a S. typhi (CT18) that is resistant to multiple drugs, revealing the presence of hundreds of insertions and deletions compared with the Escherichia coli genome, ranging in size from single genes to large islands. Notably, the genome sequence identifies over two hundred pseudogenes, several corresponding to genes that are known to contribute to virulence in Salmonella typhimurium. This genetic degradation may contribute to the human-restricted host range for S. typhi. CT18 harbours a 218,150-bp multiple-drug-resistance incH1 plasmid (pHCM1), and a 106,516-bp cryptic plasmid (pHCM2), which shows recent common ancestry with a virulence plasmid of Yersinia pestis.


4359.               Leder K, Weller PF, Wilson ME. Travel vaccines and elderly persons: review of vaccines available in the United States. Clin Infect Dis  2001 Nov 1;33(9):1553-66


Aging is associated with alterations in immune responses and may lead to clinically significant changes in the safety, immunogenicity, and protective efficacy of certain vaccines. This review summarizes published data regarding the effects of age on responses after immunization with vaccines generally administered before travel. The specific vaccines discussed in detail include hepatitis A, typhoid, yellow fever, Japanese encephalitis, and rabies vaccines. There is some evidence of diminished serological responses to hepatitis A and rabies vaccines in older individuals. In addition, increased toxic effects following yellow fever vaccination in elderly recipients have recently been reported. However, many travel-related vaccines have never been studied specifically in elderly populations. Consideration of potential age-related differences in responses to travel vaccines is becoming increasingly important as elderly persons more frequently venture to exotic destinations.

4360.               McDade TW, Beck MA, Kuzawa C, Adair LS. Prenatal undernutrition, postnatal environments, and antibody response to vaccination in adolescence. Am J Clin Nutr  2001 Oct;74(4):543-8


BACKGROUND: Recently, researchers have considered the fetal and infant origins of several adult cardiovascular and metabolic diseases, but the implications of early events for immune function and infectious disease are unclear. OBJECTIVE: We investigated the association between prenatal undernutrition and immunocompetence in adolescence and hypothesized that intrauterine growth retardation is associated with a lower likelihood of mounting an adequate antibody response later in life. DESIGN: A subsample of one hundred three 14-15-y-olds was recruited from an ongoing longitudinal study in which data collection began while participants were in utero. A typhoid vaccine was given, and anti-typhoid antibodies were measured 2 wk and 3 mo later as a functional marker of immunocompetence. The likelihood of mounting an adequate antibody response was compared for adolescents who were small for gestational age or appropriate for gestational age at birth while controlling for a range of postnatal exposures. RESULTS: The predicted probability of mounting a positive antibody response for adolescents who were prenatally and currently undernourished was 0.32, compared with probabilities of 0.49-0.70 for adequately nourished adolescents (P = 0.023). Diarrhea in the first year of life (P = 0.009) and fast weight gain during the first 6 mo (P = 0.003) were also associated with a higher probability of response. CONCLUSIONS: These findings extend the concept of fetal and early infant programming of adult diseases to the immune system and suggest that early environments may have long-term implications for immunocompetence and infectious disease risk, particularly in developing countries.


July 02

4984.               Ahmad K.  Experts call for surveillance of drug-resistant typhoid at a global level. Lancet. 2002 Feb 16;359(9306):592.

No Abstract

4985.               Gasem MH, Smits HL, Goris MG, Dolmans WM.  Evaluation of a simple and rapid dipstick assay for the diagnosis of typhoid fever in Indonesia. J Med Microbiol. 2002 Feb;51(2):173-7.

To support the clinical diagnosis of typhoid fever in Indonesia, where most hospitals and health centres have no facilities for culture, a rapid dipstick assay for the detection of Salmonella typhi-specific IgM antibodies was evaluated on serum samples from 127 patients clinically suspected of having typhoid fever. In a single blood sample collected on admission to hospital, the sensitivity of the dipstick assay was 69.8% when compared with bone marrow culture and 86.5% when compared with blood culture. The specificity as calculated for the group of patients with suspected typhoid fever but a negative culture result was calculated to be 88.9%. Of 80 patients with febrile illnesses other than typhoid fever, reactivity was observed in only three patients with dengue haemorrhagic fever. The assay uses stabilised components that can be stored outside the refrigerator, does not require special equipment, and may be of use in remote health facilities that have no culture facilities.

4986.               Kadappu KK, Rao PV, Srinivas N, Shastry BA.  Pancreatitis in enteric fever. Indian J Gastroenterol. 2002 Jan-Feb;21(1):32-3. Review.


Pancreatitis in enteric fever is rare. We report two patients with enteric fever, one due to Salmonella typhi infection and other due to S. paratyphi, who on investigation were found to have pancreatitis. Both patients recovered uneventfully.

4987.               Kalra OP; Agrawal NK; Agrawal S. Acute reversible cerebellar ataxia in typhoid fever Journal, Indian Academy of Clinical Medicine 2002 Jan-Mar; 3( 1): 96-7 No abstract.

4988.               Pandey CK, Singh N, Kumar V, Agarwal A, Singh PK.  Typhoid, hepatitis E, or typhoid and hepatitis E: the cause of fulminant hepatic failure--a diagnostic dilemma. Crit Care Med. 2002 Feb;30(2):376-8.


OBJECTIVE: To report a case of hepatitis E-induced fulminant hepatic failure associated with typhoid fever, diagnosed with the Widal test. DESIGN: Case report. SETTING: Eight-bed medical/surgical intensive care unit of a university hospital. PATIENT: A 15-yr-old, 50-kg male with grade IV hepatic encephalopathy was admitted to the intensive care unit for ventilatory support. On admission to the intensive care unit he had had fever associated with loss of appetite and nausea for 15 days, jaundice for 4 days, and altered sensorium for 2 days. INTERVENTION: He was intubated and kept on elective ventilation. Tracheal aspirate, blood, urine, and stool were sterile. Anti-coma measures were instituted in the form of 20 degrees head elevation; mannitol, lactulose, and ampicillin through a nasogastric tube; and bowel wash. The mainstay of fluid therapy was 20% dextrose. Viral marker was positive for hepatitis E. He showed a favorable recovery but continued to have high-grade fever (39-40 degrees C). On investigation, peripheral blood smear was negative for malarial parasite, and Widal was positive. Fever responded to treatment with Ceftazidime. RESULT: The patient recovered with anti-coma and anti-typhoid therapy. CONCLUSION: In viral hepatitis, fever is usually present in the prodromal phase but subsides before appearance of the icteric phase. In endemic areas, if fever is present in the icteric phase of hepatitis, typhoid also should be considered in the differential diagnosis of fever, even in the absence of positive cultures for Salmonella typhi. The Widal test may be helpful in reaching a diagnosis.

4989.               Rodrigues C, Mehta A, Joshi VR.  Salmonella typhiin the past decade: learning to live with resistance. Clin Infect Dis. 2002 Jan 1;34(1):126.

No Abstract

4990.               Stephens I, Levine MM.  Management of typhoid fever in children. Pediatr Infect Dis J. 2002 Feb;21(2):157-8. Review.  No Abstract



Oct 02

5765.               Malik AS. Complications of bacteriologically confirmed typhoid fever in children. J Trop Pediatr. 2002 Apr;48(2):102-8.


To find the incidence, markers and nature of complications of typhoid fever, we studied 102 children with cultures positive for Salmonella typhi in a cross-sectional study, prospectively, over a period of almost 5 years. All isolates were sensitive to commonly used antibiotics. One third of these children developed complications which included: anicteric hepatitis, bone marrow suppression, paralytic ileus, myocarditis, psychosis, cholecystitis, osteomyelitis, peritonitis, pneumonia, haemolysis, and syndrome of inappropriate release of antidiuretic hormone (SIADH). Twelve children developed multiple complications. If hepatitis is excluded from the complications, the rate of complications in bacteriologically confirmed cases of typhoid fever drops to 11 per cent. These complications were not related to: the age or sex of patients, duration of illness before admission, use of antibiotics before admission, nutritional status, level of 'O' or 'H' titre, presence of IgM or IgG antibodies, or treatment with chloramphenicol or ampicillin. Children with splenomegaly, thrombocytopenia or leukopenia were more likely to develop complications.


5766.               Tariq Hamid. Biological characterization of outer membrane proteins of S. typhi and S. typhimurium and studies on their role of protection against typhoid. Department of  Biotechnology, Jamia Hamdard; New Delhi, 2001. No abstract.

5767.               Vagholkar Kr. Surgical management of typhoid enteric perforation (a study of 24 cases). Hosp Today. 2001; 6(8), 461-4.
A series of 24 patients operated for typhoid enteric perforation were studied retrospectively with an aim to optimise surgical treatment. Indoor case records of 24 patients operated for typhoid enteric perforations were studied retrospectively. An evaluation of the symptomatology, laboratory and radiological investigation, surgical options and postoperative complications was done. Out of the 24 patients studied, 20 patients had a single small bowel perforation while 4 had multiple perforations of the small bowel. The surgical options used were simple two layered closure after freshening the edges in 20 patients and resection with end to end anastomosis in the 4 patients who had multiple perforations. There was only one death (Postoperative mortality was 4.16%). Prompt diagnosis, aggressive fluid and electrolyte reuscitation, antibiotic prophylaxis and optimal choice of the surgical procedure based on the individual merits of the case can only yield a positive outcome keeping the morbidity and mortality to a bare minimum.


5768.               McConkey SJ. Case series of acute abdominal surgery in rural Sierra Leone. World J Surg. 2002 Apr;26(4):509-13.


In many poor countries of the world the need for surgical treatment of acute abdominal emergencies is largely unmet. In some cases this service is provided by physicians with little postgraduate surgical training, and there is a paucity of published data on the outcomes of this service. This series of sequential cases of acute abdominal surgical emergencies from a hospital in rural Sierra Leone illustrates the causes, outcomes, and challenges in this setting. All patients with an acute abdomen from September 1992 until September 1994 who required surgery were identified by review of theater records, ward books, and patients' notes. Altogether, 173 cases were identified. Operative diagnoses included ectopic pregnancy (n = 43), strangulated hernia (n = 45) 15 of which required bowel resection, appendicitis (n = 15), normal appendix (n = 4), uterine rupture (n = 9), perforated ulcer (n = 8), tubal or pelvic abscess (n =7), volvulus (n = 6), and others. Ninety percent survived to discharge after a median postoperative stay of 9.2 days (range 7-127 days). Of the 18 deaths, 83% occurred during the first 3 days. Factors associated with poor outcome were ileal perforation due to typhoid fever and resection of bowel after a strangulated hernia. These results show that acute abdominal surgery can be done at the district level in poor countries using limited facilities by staff without extensive surgical training. The outcomes are comparable to those from larger centers.


5769.               Prouty AM, Schwesinger WH, Gunn JS. Biofilm formation and interaction with the surfaces of gallstones by Salmonella spp. Infect Immun. 2002 May;70(5):2640-9.


Salmonellae can exist in an asymptomatic carrier state in the human gallbladder. Individuals with gallstones are more likely to become typhoid carriers, and antibiotic treatments are often ineffectual against Salmonella enterica serovar Typhi in carriers with gallstones. Therefore, we hypothesized that Salmonella spp. form biofilms on the surfaces of gallstones, where the bacteria are protected from high concentrations of bile and antibiotics. A number of methods were utilized to examine biofilm formation on human gallstones and glass coverslips in vitro, including confocal, light, and scanning electron microscopy. In our assays, salmonellae formed full biofilms on the surfaces of gallstones within 14 days and appeared to excrete an exopolysaccharide layer that bound them to the surfaces and to other bacteria. Efficient biofilm formation on gallstones was dependent upon the presence of bile, as a biofilm did not form on gallstones within 14 days in Luria-Bertani broth alone. The biofilms formed by a Salmonella enterica serovar Typhi Vi antigen mutant, as well as strains with mutations in genes that eliminate production of four different fimbriae, were indistinguishable from the biofilms formed by the parents. Mutants with an incomplete O-antigen, mutants that were nonmotile, and mutants deficient in quorum sensing were unable to develop complete biofilms. In addition, there appeared to be selectivity in salmonella binding to the gallstone surface that did not depend on the topology or surface architecture.These studies should aid in the understanding of the Salmonella carrier state, an important but underresearched area of typhoid fever pathogenesis. If the basis of carrier development can be understood, it may be possible to identify effective strategies to prevent or treat this chronic infection.


5770.               Aggarwal A, Dutta AK. Typhoid Vaccines. Indian J. Pediat 2001; 68(8): 735-6.
Typhoid fever continues to be a major public health problem in developing countries with about 33 million cases per year. Protective efficiency of traditional acetone/phenol killed vaccines is similar to newer typhoid vaccines (TY21A and Vi antigen vaccine) but side effects of these newer vaccines are considerably less. Though the mortality is low, typhoid fever causes considerable morbidity and loss of working days. Problems during treatment are increasing due to emergence and spread of multidrug resistant S. typhi. Hence to decrease the incidence of typhoid fever in addition to ensuring safe water supply and excreta disposal a typhoid vaccine needs to be introduced in the National Immunization Schedule.

5771.               White Jr AC, Atmar RL. Infections in Hispanic immigrants. Clin Infect Dis. 2002 Jun 15;34(12):1627-32.


Hispanic immigrants are an increasing portion of the United States (US) population. In addition to being at risk for diseases common in the US-born population, Hispanic immigrants also are at risk for infections that do not usually occur in the US-born population. Thus, such diseases as tuberculosis, neurocysticercosis, brucellosis, typhoid fever, malaria, amebiasis, viral exanthems, and hepatitis need to be considered in Hispanics who present with fever or focal lesions. When included in the differential diagnosis, most of these infections can be readily diagnosed and treated with currently available methods.



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