Meningoccocal disease has repeatedly caused outbreaks worldwide. There has been sudden surge of cases of meningococcemia and meningococcal meningitis in early 2005 in Delhi, India and neighboring states of Uttar Pradesh and Haryana. As of June 17, 2005, 429 probable cases of meningococcal disease have been reported in Delhi out of which 128 cases have revealed microbiological evidence of Neisseria meningitidis . It is possible that the number of cases was in excess of the numbers notified. During this episode drug susceptibility testing by MIC method (E-test) using break points recently recommended by NCCLS/CLSI, revealed that all isolates were sensitive to penicillin, ampicillin, rifampicin and ceftriaxone. As regards to ciprofloxacin, about two third of the isolates tested were found to be 'non-susceptible' (MIC =0.03µg/mL- 0.190µg/mL). All the isolates were found resistant to cotrimoxazole (MIC> 16µg/mL). Repeated outbreaks, decreased susceptibility to ciprofloxacin, which is commonly used for chemoprophylaxis of meningococcal disease, highlights the need for a constant surveillance system. Present review deals with various aspects of Neisseria meningitidis and meningococcal disease in view of recent episode.

Treatment of extended spectrum beta-lactamase (ESBL) producing strains of Enterobacteriaceae has emerged as a major challenge in hospitalised as well as community based patients. Infections due to ESBL producers range from uncomplicated urinary tract infection to life threatening sepsis. Although several reviews have been published in the literature about the detection and identification of these pathogens in the laboratory, there is not much guidance in Indian literature about how these organisms should be treated in clinical settings. The present article tries to address the clinical questions in the management of ESBL producing organisms. The article emphasises on antibiotic choice, pharmaco-therapeutic considerations, non-antibiotic aspects of management, and testing of clinical samples in the initial screening of patients for resistant gram negative organisms.

Purpose: The purpose of this study was to evaluate three methods for detection of biofilm formation in staphylococci. Methods: For detection of biofilm formation, 152 clinical isolates of Staphylococcus spp. were screened by tissue culture plate (TCP), Tube method (TM) and Congo red agar (CRA) method. Results: Of the 152 Staphylococcus spp. 88(57.8%) displayed a biofilm-positive phenotype under the optimized conditions in the TCP method and strains were further classified as high 22 (14.47 %) and moderate 60 (39.4 %) while in 70 (46.0 %) isolates weak or no biofilm was detected. Though TM correlated well with the TCP test for 18 (11.8 %) strongly biofilm producing strains, weak producers were difficult to discriminate from biofilm negative isolates. Screening on CRA does not correlate well with either of the two methods for detecting biofilm formation in staphylococci. Conclusion: The TCP method was found to be most sensitive, accurate and reproducible screening method for detection of biofilm formation by staphylococci and has the advantage of being a quantitative model to study the adherence of staphylococci on biomedical devices.

Purpose: To determine the role of humoral immune response and bacterial adherence in the pathogenesis of symptomatic and asymptomatic urinary tract infection in women. Methods: The study population consisted of 30 women with symptomatic UTI, 30 women with asymptomatic UTI and 30 healthy women as controls. Bacterial adherence to vaginal epithelial cells was studied and the concentration of serum and urine antibodies to mixed coliform antigen and clinical isolate was determined by ELISA. Surface hydrophobicity of the urine isolates was determined. Student's unpaired t test and Pearson's correlation coefficient test were used in the statistical analysis. Results: Compared to asymptomatic UTI, significantly more number of bacteria adhered to the epithelial cells of women with symptomatic UTI (P<0.001). All cases of UTI had significantly high concentration of urinary IgG antibody to mixed coliform antigens. Asymptomatic UTI cases had higher concentrations of urinary IgG, IgM and IgA antibodies to clinical isolate. Concentration of sIgA level was more in symptomatic UTI. Significant correlation was observed between urinary IgG and adherence of clinical isolate in case of asymptomatic UTI. Conclusions: The present study showed that greater receptivity of epithelial cells to bacteria may increase the susceptibility to UTI. Humoral immune response and local immunity may modify the pathogenesis of UTI.

Purpose: Methicillin resistant Staphylococcus aureus (MRSA) is an important nosocomial pathogen. We report the prevalence and antibiotic susceptibility pattern of MRSA in major southern districts of Tamilnadu. Methods: A total of 7172 clinical specimens and 1725 carrier screening samples were collected from different centers and subjected to MRSA screening using conventional microbiological methods. Subsequently the antibiotic sensitivity test was performed for the confirmed MRSA isolates. Results: Out of 906 strains of S. aureus isolated from clinical and carrier samples, 250 (31.1%) and 39 (37.9%) were found to be methicillin resistant respectively. Almost all clinical MRSA strains (99.6%) were resistant to penicillin, 93.6% to ampicillin, and 63.2% towards gentamicin, co-trimoxazole, cephalexin, erythromycin, and cephotaxime. All MRSA strains (100%) of carrier screening samples had resistance to penicillin and about 71.8% and 35.9% were resistant to ampicillin and co-trimoxazole respectively. Multidrug resistance was observed among 63.6% of clinical and 23% of carrier MRSA isolates. However, all strains of clinical and carrier subjects were sensitive to vancomycin. Conclusion: The determination of prevalence and antibiotic sensitivity pattern of MRSA will help the treating clinicians for first line treatment in referral hospitals.

Purpose: Nosocomial infections caused by Acinetobacter species is of increasing concern in critically ill patients, and the risk factors for this infection are not well established. The present investigation was done to determine incidence of nosocomial Acinetobacter infections. Our study retrospectively attempts to find risk and prognostic factors for the nosocomial acquisition of Acinetobacter infection. Methods: The medical records of 43 patients with Acinetobacter infection during two-year period (Oct1998-Oct2000) were reviewed to find the factors involved in the nosocomial acquisition of Acinetobacter . Acinetobacter isolates that were obtained from these patients were phenotypically typed using carbon assimilation tests. Antimicrobial susceptibility testing results were noted from the microbiology records. Results: Acinetobacter baumannii accounted for 41.8% (n=18) of all the infections. By multivariate logistic regression analysis, only resistant antibiotype {(Ceftazidime- OR, 7.13 [95% CI, 1 to 46];p= 0.044); (Cefotaxime- OR, 6.09 [CI, 0.87 to 30];p = 0.045)} and mechanical ventilation (OR, 5.84 [CI, 0.83 to 31];p = 0.05) were found to be potential independent risk factors for mortality. Overall mortality rate was 33%. Conclusions: Most of A. baumannii isolates were multidrug resistant in our set up and infections due to them were associated with high mortality. Prevention of Multiple drug resistant (MDR) A. baumannii infections was achieved after discontinuation of cefotaxime in ICU. Infection with resistant clones and mechanical ventilation were found to be potential independent risk factors for mortality.

The present study was undertaken to compare the changing trends of antibiograms of Salmonella enterica serovar Typhi and Salmonella enterica serovar Paratyphi A isolates. A total of 80 isolates of salmonella obtained from blood cultures between 2001-2004 were included in the study. Identification and antibiotic sensitivities of the isolates were performed by using mini API (bio Merieux, France). Sixty isolates were identified as Salmonella enterica serovar Typhi and 20 were identified as Salmonella enterica serovar Paratyphi A. More than 67% of S.typhi and 80% of S.paratyphi A isolates were sensitive to chloramphenicol. Sensitivity of S.typhi isolates to cephalosporins was found to have increased from 2001-2004 while that of S.paratyphi A showed a decline. With increasing resistance to ciprofloxacin and the possibility of re-emergence of sensitivity to chloramphenicol, the policy of empirical treatment of enteric fever needs to be rationalized.

Rapid diagnosis is a prerequisite for institution of effective treatment and reducing the mortality and morbidity of falciparum malaria. This study was taken up to compare the efficacy of various rapid methods viz, acridine orange, Plasmodium falciparum histidine rich protein II antigen detection and Field's stain with traditional microscopy i.e., Leishman stain for diagnosing falciparum malaria. Thick and thin blood films of 443 consecutive patients with history of fever with chills and rigors were examined by Leishman and Field's method. Acridine orange stained wet mounts of blood were examined under fluorescence microscopy. All films were examined by two independent microbiologists. Plasmodium falciparum histidine rich protein II antigen was detected using commercially available kit, Paracheck Pf. Out of the 443 subjects examined for P.falciparum 18.28% were detected by Leishman stain, 6.32% by Field's stain, 18.28% by acridine orange and 18.1% by antigen based technique. Field's stain missed 53 (65.4%), while Paracheck Pf was negative in 6(7.4%) of the Leishman positive samples. All Field's stain and acridine orange positives were positive by Leishman, but five Paracheck Pf positives were negative. Leishman stain is cost effective but if facilities are available one should use acridine orange for screening. The antigen detection kits are rapid, simple and are useful but to rule out false negatives in clinically suspected cases, Leishman stain is reliable.

Central nervous system (CNS) shunt infection is a cause of significant morbidity, causing shunt malfunction and chronic ill health. This study was carried out to evaluate the infection rate associated with CNS shunts, assess the frequency of the pathogens as well as their antibiotic sensitivity pattern aiming at suitable prophylaxis. A retrospective analysis of 226 CSF cerebrospinal fluid (CSF) shunt procedures sent for bacteriological work up over a period of one year and six months was undertaken. Laboratory diagnosis was established by subjecting the CSF to cell count, biochemical tests, bacteriological culture and antibiotic susceptibility test. Nine out of 226(3.98%) of the CSF samples were culture positive. Coagulase negative Staphylococcus was the most common isolate accounting for 36.36%. Majority of the isolates were sensitive to the thirdgeneration cephalosporins and quinolones. The antibiotic sensitivity pattern suggests cephalosporins and quinolones to be a better choice of antibiotics either prophylactically or therapeutically, which may result in effective and rapid sterilisation of the CSF.

An enzyme immuno assay for hepatitis C core antigen was recently developed and its performance was compared with that of the hepatitis C virus (HCV) RNA in the screening of HCV infection in patients on hemodialysis. One hundred and eleven chronic renal failure patients undergoing haemodialysis between May 2003 and October 2004 were included in the study. All the patients were tested for anti HCV antibody, core antigen and RNA. Fifteen patients were anti HCV antibody positive, three patients were positive for HCV core antigen and RNA, three patients were positive for HCV RNA, while two patients were positive only for core antigen but negative for RNA. In anti HCV antibody positive patients, the core antigen was negative while the viral RNA continued to be present. Hence, relying solely on a single HCV core antigen assay may not be useful for a definite diagnosis of early HCV infection. The sensitivity and specificity of the assay were 60% and 83% respectively, while the positive predictive value was 14.3%, negative predictive value was 97.7% and the efficiency was 81.9%.

Saksenaea vasiformis is an emerging human pathogen, most often associated with cutaneous or subcutaneous lesions following trauma. This is the report of a case of subcutaneous zygomycosis from which Saksenaea vasiformis was isolated on culture. As the patient developed acute interstitial nephritis, amphotericin B could not be administered in full dose. Surgical debridement was carried out, but the patient deteriorated gradually and died. To the best of our knowledge, this is the first reported case of Zygomycosis due to Saksenaea vasiformis from Visakhapatnam.

Zoonotic filariasis caused by Dirofilaria repens , a parasite of carnivores occurs mainly in countries surrounding Mediterranean region. The infection occurs in and around eye among animal handlers through vector transmission. We are reporting a case of human Dirofilariasis affecting subtenons region in a 63 year-old woman from Coimbatore, South India. The purpose of this article is to review the clinical course and management of ocular Dirofilariasis.

The reported case is of primary pulmonary nocardiosis, caused by Nocardia brasiliensis , in a immunocompromised patient, which ended fatally despite appropriate treatment. The partially acid fast filamentous bacterium was predominant on direct examination of the sputum. It was cultured on blood agar, MacConkey agar and by paraffin baiting technique. The bacterium was resistant to cotrimoxazole, the drug of choice for nocardiosis.

The incidence of fungal infections is increasing due to immunocompromised states. We report a case of fungaemia due to a rare fungus - Verticillium , in a 6 year old child diagnosed as a case of acute lymphoblastic leukaemia- L1 with high grade fever. The patient was treated with amphotericin B with a good clinical response.

Small, chalky-white, threadlike, motile worms were isolated from the conjunctival sac of a 32 year-old woman residing in the Himalaya mountains. They were identified as both male and female worms of Thelazia callipaeda . To the best of our knowledge, this is the second case report of human thelaziasis from India.

Genitourinary myiasis, associated with ulcerating lesions and poor hygiene of the local site, has been infrequently reported. We report a case of 45 year-old urinary incontinent female suffering from carcinoma cervix, who presented with genitourinary myiasis. The larva was identified as of Chrysomyia bezziana Villeneuve ( C. bezziana ).

Human trypanosoma infections like the ones seen in Africa and South America are unknown in India. The only exception in literature is of two documented cases of a self-limiting febrile illness, being attributed to Trypanosoma lewisi like parasites. We are reporting an unusual case of trypanosomiasis from the rural parts of Chandrapur district in Maharashtra. An adult male farmhand who used to practice veterinary medicine also, presented with history of febrile episodes on and off since five months and drowsiness before admission to this Institute. Though routine blood and other investigations were within normal limits, the peripheral smear showed a large number of trypanosomes which morphologically resembled the species Trypanosoma evansi , the aetiological agent of surra - a form of animal trypanosomiasis. A battery of assays covering the spectrum of parasitology, serology, and molecular biology confirmed the infecting parasite to be T. evansi . Failure to demonstrate the central nervous system (CNS) involvement, as evidenced by the absence of parasite in cerebrospinal fluid (CSF) advocated the use of suramin - the drug of choice in early stage African trypanosomiasis without any CNS involvement. Suramin achieved cure in our patient. The case is being reported because of its unique nature as the patient was not immunocompromised and showed infestation with a parasite which normally does not affect human beings.