occurrence of blaNDM-1 & absence of blaKPC genes encoding carbapenem resistance in uropathogens from a tertiary care centre from north India.

Background & objectives: Carbapenem resistance mediated by carbapenemases is increasingly being reported worldwide. This study was conducted to know the occurrence of important carbapenem resistance encoding genes in gram-negative bacilli (GNB) causing complicated urinary tract infection (CUTI), and to look at the genetic diversity of these isolates. Methods: The study was carried out on 166 consecutive carbapenem resistant uropathogens (CRU) isolated from cases with CUTI during 2008 and 2012. Carbapenemase production was characterized phenotypically and polymerase chain reaction was used to detect blaVIM, blaIMP, blaKPC, and blaNDM-1. BOX- PCR was done on 80 randomly selected isolates for molecular typing. Results: The blaVIM gene was present in 34 (43.6%), blaIMP in five (6.4%) and none of the isolates from 2008 had blaNDM-1 or blaKPC genes. Among the isolates from 2012, blaNDM-1 gene was present in 47 (53.4%), blaVIM in 19 (24.4%), blaIMP in one (1.1%) and none had blaKPC. There were nine isolates during the two years which had multiple genes encoding carbapenemases; while 66 did not have any of the genes tested. Of the 80 isolates subjected to BOX-PCR, 58 could be used for analysis and showed, presence of multiple clusters of carbapenem resistant isolates and absence of a single dominant clone. Interpretation & conclusions: The blaNDM-1 gene was absent in our isolates obtained during 2008 but was present amongst Enterobacteriaceae isolated in 2012. The blaKPC gene was also not found. Nine isolates obtained during the two years had multiple genes encoding carbapenemases confirming the previous reports of emergence of GNB containing genes encoding multiple carbapenemases. Typing using BOX-PCR indicated that this emergence was not because of clonal expansion of a single strain, and multiple strains were circulating at a single point of time.

Hospital acquired urinary tract infection by multidrug-resistant Brevundimonas vesicularis.

Infections caused by Brevundimonas vesicularis, a nonfermenting Gram-negative bacterium, are very rare. Here, we report the first case of multidrug-resistant hospital acquired urinary tract infection by B. vesicularis. Patient was successfully treated with antimicrobial therapy with piperacillin-tazobactam and amikacin.

Evaluation of commercial boric acid containing vials for urine culture: Low risk of contamination and cost effectiveness considerations.

Background: Urine culture is a gold standard in the diagnosis of urinary tract infection. Clean catch midstream urine collection and prompt transportation is essential for appropriate diagnosis. Improper collection and delay in transportation leads to diagnostic dilemma. In developing countries, higher ambient temperatures further complicate the scenario. Here, we have evaluated the role of boric acid as a preservative for urine samples prior to culture in female patients attending outpatient department at our center. Materials and Method: Consecutive 104 urine samples were cultured simultaneously in plain uricol (Control-C) and boric acid containing tubes from Becton Dickinson urine culture kit (Boric acid group-BA). Results: In the real-time evaluation, we found that in almost 57% (59/104) of the urine samples tested, it was more effective in maintaining the number of the organisms as compared to samples in the container without any preservative. Our in vitro study of simulated urine cultures revealed that urine samples could be kept up to 12 h before culture in the preservative without any inhibitory effect of boric acid. Though the use of boric acid kit may marginally increase the initial cost but has indirect effects like preventing delays in treatment and avoidance of false prescription of antibiotics. If the man-hours spent on repeat investigations are also taken into consideration, then the economic cost borne by the laboratory would also decrease manifold with the use of these containers.

Antimicrobial resistance in selected bacterial enteropathogens in north India.

BACKGROUND & OBJECTIVES: The resistance of enteropathogenic bacteria to commonly prescribed antibiotics is increasing both in developing as well as in developed countries. Resistance has emerged even to newer, more potent antimicrobial agents. The present study was therefore undertaken to report the current antibiotic resistance in common bacterial enteropathogens isolated in a tertiary care hospital in north India. METHODS: Faecal samples from 1802 patients were cultured for common bacterial enteropathogens and identified by standard methods. Antibiotic susceptibility was done by Stoke's disk diffusion method. The clinical and demographic profile of the patients was noted. RESULTS: Stool specimens from 119 (88 male, 31 female) patients yielded Shigella, Salmonella, Vibrio cholerae or Aeromonas. Fifty two per cent (62/119) of patients were children and 70 per cent were below the age of 5 yr. Twenty seven patients developed hospital acquired diarrhoea. Among all enteropathogens, Shigella spp. was the commonest followed by non-typhoidal Salmonella (27), V. cholerae O1 El tor serotype Ogawa (19), Aeromonas spp. (14), Salmonella Typhi and S. paratyphi A (2 isolates each). Resistance to antimicrobial agents was common among all pathogens. Among shigellae an overall resistance of 63.6, 58.1 and 16.3 per cent was observed for nalidixic acid, cotrimoxazole and furazolidone respectively. Seven isolates of Shigella were resistant to ciprofloxacin, (18.5%) of non-typhoidal salmonellae were resistant to ciprofloxacin. V. cholerae were generally susceptible to tetracycline (only 1 isolate out of 13 resistant) and other drugs except nalidixic acid (89.5% resistance) and cotrimoxazole (77.8% resistance). INTERPRETATION & CONCLUSION: Enteropathogens have developed high level resistance to first line agents used for empiric treatment of diarrhoea. Progressively increasing resistance to ciprofloxacin is a serious cause of concern.

Heterophile antibody positive infectious mononucleosis.

OBJECTIVE: The present study has been carried out to analyse the trend of heterophile antibody positive infectious mononucleosis cases. METHODS: A total of 1741 cases of clinically suspected infectious mononucleosis from various age groups were investigated during the period January, 1986 to December, 2000 and were analysed for infectious mononucleosis (IM) specific heterophile antibody by Paul-Bunnel-Davidsohn (PBD) test. Forty seven heterophile antibody negative samples were also tested simultaneously for the presence of the IgG antibody to viral capsid antigen (VCA) and Epstein Barr nuclear antigen (EBNA) to detect the exposure to Epstein Barr Virus (EBV) infection. RESULTS: The overall percentage of EBV specific heterophile (Paul-Bunnel) antibody positivity was found to be 11.1% (194/1741). The average Paul-Bunnel antibody positivity between 1986 to 1990 was 20.5% which declined drastically to 5.7% during 1991-2000. Males comprised of 55.2% of the serologically proven IM cases. Of the 47 heterophile antibody negative cases, 38 (80.9%) and 33 (70.2%) were found to be positive for anti-VCA IgG and anti-EBNA IgG antibodies respectively. Paul Bunnel antibody positivity was found to be higher in >14 year age group patients than those below 14 years. CONCLUSION: These findings suggest that the EBV infection still continues to be endemic in this part of the country, however, a declining trend in IM cases was observed during the last decade.

Seroepidemiological study of toxoplasmosis in different sections of population of Union Territory of Chandigarh.

Infections with Toxoplasma gondii in humans are usually asymptomatic or in the form of mild febrile illness. Primary infection in pregnant women may result in congenital toxoplasmosis while infection in immunocompromised subjects like AIDS patients may cause potentially fatal toxoplasma encephalitis. In India, only a few studies in hospital based patients have shown prevalence of toxoplasmosis to be between 1.5 and 21%. No field study involving general population is available. The present study investigates the prevalence of toxoplasmosis in subjects from rural, urban and urban slum populations of Union Territory, Chandigarh. Serum samples from 500 subjects from each group were collected and antitoxoplasma IgM and IgG was detected by conventional micro ELISA technique using soluble Toxoplasma gondii tachyzoite antigen. Overall 5.4% subjects were positive for IgM while 4.66% showed IgG antitoxoplasma antibodies. Amongst the three groups, significantly higher number of subjects in slum area (7.8%) showed IgM antibodies as compared to urban and rural areas (4.2% each). There was no significant difference in IgG positivity between three study areas. Prevalence of T. gondii specific IgG antibodies was significantly higher amongst females of both slum (7.31%) and rural area (8.44%) as compared to the males (2.85% and 3.27% respectively) in the same areas (p<0.05) and also to females of the urban area (2.98%, p<0.05). Prevalence of IgM antibodies was significantly higher (p<0.05) in females in the slum area (10.5%) as compared to females in the urban area (2.55%). In both urban and slum areas, highest IgM seropositivity was observed in age group 6-12 years (10% and 13.3% respectively), while in the rural area the highest IgM seropositivity was seen in the age group > or = 5 years (17.7%). These data indicate that majority of children are exposed to toxoplasma before 12 years of age and particularly in rural areas higher number of subjects acquire Toxoplasma gondii infection early in childhood probably as a result of higher exposure due to farming, poor hygiene and handling of animals.