Evaluation of Various Non Culture Methods for the Diagnosis of Spontaneous Bacterial Peritonitis

Introduction: Spontaneous Bacterial Peritonitis (SBP) iscommon and serious complication of patients with livercirrhosis and ascites, without an apparent surgically treatableintra abdominal source of infection. Its prevalence rangesfrom 10% to 30%. Mortality rate was earlier reported morethan 90%, but it has now reduced to 30% -50% as a resultof rapid diagnosis and prompt initiation of antibiotics. Thepresent study was done to evaluate the various non culturemethods for the diagnosis of SBP.Material and Methods: Ascitic fluid sample were collectedaseptically from 100 cirrhotic patients with ascites. PMN(polymorphonuclear leukocyte) count was determined byNeubauer’s manual counting chamber and Leishman’s stainfor differential PMN cell counts. Granulocyte esterase activitywas detected using LER (Leukocyte esterase reagent) dipstickstrips.Results: Out of 100 samples processed, PMN cell count >250 cells/mm3 was found in 91% samples by conventionallight microscopy. Scale of > 2+ by LER strip was found in61 samples. Reading of PMN cell count of > 250 cells/mm3matched in 60 samples and < 250 cells/mm3 matched in 8 cellsby both microscopy and LER strip test. Sensitivity, specificity,positive predictive value and negative predictive value ofLER strip test was 65.9%, 88.89%, 98.36% and 20.51%respectively.Conclusion: LER strips as a screening tool for SBP haveadvantage of speed, low cost, availability at odd hours, requiresno technical expertise and can be performed everywhere.Its high specificity and PPV may help in early institution ofempirical antibiotic therapy in patients.

Fecal carriage of carbapenem resistant Enterobacteriaceae among the intensive care unit patients

Background: The war against multidrug-resistant bacteria is challenging and of global concern. Hospitals are increasingly plagued by resistant gram negative pathogens. Bacteria of the family Enterobacteriaceae such as Escherichia coli and Klebsiella pneumoniae are part of the normal human intestinal flora but are also often responsible for community- and healthcare-associated infections. These bacteria are prone to acquiring resistance genes.Methods: Rectal swabs/swabs from the peri-anal area of the patients who were admitted in the Intensive Care Unit (ICU) of the accident and emergency department of this teaching hospital. Swabs were collected first on day 1 of admission, then day 4, and thereafter weekly during the period of stay in the ICU. All the swabs were immediately inoculated into trypticase soy broth with one 10μg  meropenem disc and were incubated overnight at 35±2ºC, ambient air. Next day, the broth was vortexed, and then sub-cultured onto a MacConkey agar plate. On the third day, MacConkey agar plates were examined for lactose fermenting (pink-coloured) colonies. The representative isolated colonies were subjected to conventional antimicrobial susceptibility testing by the Kirby Bauer Disc diffusion method following the CLSI guidelines to know the susceptibility to carbapenem and other antimicrobial agents. Carbapenemase production was done by a Modified Hodge Test (MHT) and Imipenem-EDTA test.Results: Out of 89 patients, carbapenem resistant Klebsiella pneumoniae and E. coli isolates were recovered from 35 (39.3%) patients i.e. Klebsiella pneumoniae isolates from fifteen patients and carbapenem resistant E. coli isolates from twenty patients. Prevalence of carbapenemase producing isolates was found to be 1.42%.  Conclusions: Surveillance for CRE can definitely help reduce rates of healthcare associated infections.

Resistance Pattern of Escherichia coli Isolates from Surgical Wound Infections.

Background: Surgical wound infections, are common post-operative complications, that cause significant postoperative morbidity and mortality. Aim of the study: To isolate, identify and study the antimicrobial sensitivity of E. coli isolates from surgical wounds. Methodology: A total of 1088 pus samples were received over a period of one year from post-operative wounds. 313 isolates of E. coli were recovered and identified and antimicrobial sensitivity testing (AST) including extended spectrum beta lactamases (ESBL) detection was performed according to Clinical Laboratory Standard Institute (CLSI) guidelines. Results: E. coli accounted for 37.5% . ESBL production was detected in 22.0% of E. coli isolates. Conclusion: Our study shows that there is increased isolation rate of E. coli from post-operative wound infections. Hospital disinfection and treatment protocols should be practiced thoroughly and regularly monitored to control the incidence of wound infections.

Dental caries, gingivitis, periodontitis: a review

Microbial populations colonizing the teeth and periodontal tissues are a major source of pathogens responsible for oral and dental infections including dental caries, gingivitis, periodontitis etc. Dental caries is a multifactor and infectious disease resulting dueto interaction of three different aspects like dietary sugar, susceptible tooth enamel and oral microbial colonization. Plaques from caries active sites have significantly higher proportion of Streptococcus mutans (principle acid producer) with pH levels of 5.0 or lower. Dental decay occurs when normal demineralization remineralization is disturbed. On the other hand the most common form of gingivitis is chronic or long standing plaque induced gingivitis while acute necrotizing ulcerative gingivitis is most aggressive, developing gingivitis is associated with increasing numbers of Actinomyces israeliwhereas gingivitis with bleeding is associated with A. viscosus and pigmented Bacteroides. Periodontitis is defined as loss of alveolar support to the tooth and can be differentiated microbiologically and clinically into adult, localised juvenile and pre-pubertal periodontitis. Various species of Bacteroides, Actinomyces, Fusobacterium etc. have been isolated from cases of active periodontitis. Thus wherever possible both aerobic and anaerobic culture should be performed and appropriate antibiotic therapy should be prescribed instead of empirical treatment.