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V Talwar

Publications and source records attributed to V Talwar.

At least 37 records · Page 2Linked to original sources
PubMed1997

Anaerobic flora in endodontic infections.

Microbiological and clinical data from 56 patients with endodontic infections were evaluated. Samples were collected using autoclaved paper points. Specimens were processed for isolation of aerobic and anaerobic bacteria. Antimicrobial sensitivity and resistance profiles of the recovered isolates was also performed. Forty nine positive cultures (87.5%) were obtained from the 56 consecutive necrotic root canal systems which were sampled. A total of 69 aerobic bacteria and 21 anaerobic bacteria were recovered. Aerobic bacteria were isolated from 35 patients (72%), anaerobic bacteria from 3 (6%) and mixed aerobic and anaerobic bacteria from 11 patients (22%). The most common aerobic isolate was Klebsiella pneumoniae. The predominant anaerobic isolate was Bacteroides species. One isolate was recovered from 25 patients (51%) whereas in the remaining 24 patients (49%) more than 1 isolate were recovered. These data illustrate the polymicrobial nature of endodontic infections in half the patients studied and the role of anaerobic bacteria in a quarter of them.

Bacteria, Anaerobic↗
PubMed1997

Changing patterns of Vibrio cholerae isolation over three consecutive cholera seasons (1992-1994) in east Delhi.

The emergence of new strains of Vibrio Cholerae has added a new dimension to the variability in pathogenicity and potential virulence of the organisms precipitating diarrhoeal diseases. Considering the shifting patterns of V. cholerae 01 there is a continuous need to monitor the strain characteristics. In this study total 541 stool specimens of acute secretory diarrhoea were investigated between May 1992 and November 1994 for strains of Vibrio Cholerae and anti-microbial susceptibility testing of all the confirmed V. Cholerae strains. In 1992, 50 of the 125 strains (40%) were positive for V. cholerae 01 predominantly biotype El Tor serotype ogawa, and 10 (80%) of non 01 type, with most strains susceptible to tetracycline (100%), chloramphenicol (98%) and Cotrimoxazole (98%), but all resistant to polymyxin B and furazolidine. In 1993, 44 (43.6%) of the 010 strains were positive for V. cholerae 0139 and the rest V. cholerae 01. In 1994, another sero group of V. cholerae 010 emerged, with 42 (13.3%) being positive. Isolates did not agglutinate with any of these antisera and have been labelled as 'other than non-01 vibrio cholerae'.

Case-Control Studies↗
PubMed1997

Serum and cerebrospinal fluid concentrations of rifampicin at two dose levels in children with tuberculous meningitis.

Twenty patients of tuberculous meningitis (TBM) in age group of 6 months to 10 years included in the study were divided into two groups of 10 patients each. Rifampicin was administered in dosage of 10 mg and 7.5 mg/kg bw to each patient of groups I and II respectively. Drug concentrations in serum and CSF of these patients were measured by a microbiological tube dilution method using a strain of Sarcina lutea. In group I mean serum and CSF concentration was 3.84 micrograms/ml and 0.178 microgram/ml respectively, while in group II it was 2.16 micrograms/ml and 0.206 microgram/ml respectively. These concentrations were many times higher than the MIC against Mycobacterium tuberculosis. Mean percentage penetration of rifampicin in CSF was 5 and 10% in group I and II respectively. We recommend similar studies in large number of children before advocating the therapy with low dose of rifampicin in TBM.

Antibiotics, Antitubercular↗
PubMed1996

Cluster of cases of clinical cholera due to Vibrio cholerae 010 in east Delhi.

A total of 514 samples of acute diarrhoeal stools received over a period of four months yielded 315 isolates morphologically and biochemically resembling V. cholerae. Out of 315 isolates, 223 (70.8%) were identified as V. cholerae 01, 20 (6.4%) as 0139 and 42 (13.3%) as 010. Thirty (9.5%) isolates did not agglutinate with any of the available antisera. All V. cholerae 010 isolates showed complete homogeneity in their biochemical and physiological properties. This strain appears to be closely related to El Tor biotype of V. cholerae 01, since it was positive for some of the tests used for identification of El Tor. The ability of strain 010 to grow in the presence of 6 per cent salt provides it the status of an important environmental pathogen. Acquisition of some virulence genes from El Tor vibrios by this strain 010 appears to be one of the mechanisms involved in the emergence of this serogroup.

Cholera↗
PubMed1996

Initial and acquired drug resistance of Mycobacterium tuberculosis in east Delhi.

One hundred and fifty six strains of Mycobacterium tuberculosis, isolated from cases of pulmonary tuberculosis were subjected to sensitivity test to detect initial and acquired drug resistance to Streptomycin, isoniazid, Rifampicin, Ethambutol and Pyrazinamide. Initial and acquired drug resistance was observed to one or more drugs in 16% and 24.4% of the patients respectively. Strains resistant to Rifampicin and Ethambutol were resistant to Isoniazid also. Drug resistance was unrelated to age and sex of the patients.

Antitubercular Agents↗
PubMed1996

Detection of IgM antibodies in pulmonary tuberculosis by ELISA using A60 antigen.

An enzyme immunosorbent assay (ELISA) was evaluated as a serodiagnostic test in patients with active tuberculosis (Group I), clinically suspected pulmonary tuberculosis (Group II) and pulmonary diseases other than tuberculosis and normal healthy subjects (Group III). and compared with culture and sputum smear examination results. ELISA was found to have a sensitivity of 77.5% and a specificity of 87.5%. Sputum smear had a sensitivity of 65% and specificity of 100%. In patients clinically suspected to have pulmonary tuberculosis ELISA had a sensitivity of 60%. Thus ELISA using A60 antigen can facilitate the diagnosis of tuberculosis in patients with active as well as suspected pulmonary tuberculosis and can provide results within hours of receipt of samples.

Adolescent↗
PubMed1996

Activity of third generation cephalosporins against Pseudomonas aeruginosa in high risk hospital units.

Ceftazidime and Cefoperazone are the two third generation cephalosporins with anti-pseudomonal activity. They have been frequently used in the I.C.U.s. in the developed countries but their use in the Indian hospitals has begun relatively recently. We studied the in-vitro susceptibility of 139 Pseudomonas aeruginosa isolates that were multiple drug resistant from the Resuscitation Unit/I.C.U. (61 strains), Burns Unit (48 strains), Surgical Post-operative unit (24 strains), Nephrology unit (6 strains) of our hospital to these two cephalosporine over a period of about 18 months. Antibiotic susceptibility was studied using Kirby Bauer's disc dibusion method. Out of a total of 139 strains of multiple drug resistant Pseudomonas aeruginosa tested, 17.9% were found resistant each to Ceftazidime and Cefoperazone separately and 10% were found resistant to both antibiotics.

Cephalosporins↗
PubMed1996

Anaerobic and aerobic microflora of pouch of Douglas aspirate v/s high vaginal swab in cases of pelvic inflammatory disease.

The anaerobic and aerobic bacterial flora in pouch of Douglas (POD) aspirate and high vaginal swabs (HVS) was studied in 43 cases of pelvic inflammatory disease (PID) using standard techniques. High vaginal swabs from 20 healthy women were included as controls. Anaerobic and aerobic bacteria were isolated from 37 (86%) HVS and 31 (72%) POD aspirates from these 43 women. A total of 100 aerobic and 10 anaerobic bacterial strains were recovered from both the sites. Coagulase negative staphylococci (28), Escherichia coli (23) and Streptococcus faecalis (14) were predominant aerobic bacteria. Of the anaerobes, peptostreptococci species and Bacteroides species were more common, polymicrobial flora (more than one type of organism) was present in a total of 27 specimens. However mixture of anaerobic and aerobic bacteria were seen in only 5 specimens. Of the 20 control specimens, ten were positive for organisms. Ten aerobic and 3 anaerobic bacterial strains were recovered.

Adult↗
PubMed1996

Characterisation of Vibrio cholerae 0139 isolated from diarrhoeal stools.

A total of 174 samples of acute diarrhoeal stools received over a period of seven months, yielded 101 isolated morphologically and biochemically resembling Vibro cholerae. Serologically, 57(56.4 per cent) of the 101 isolates were identified as V. cholerae 01 and remaining 44 (43.6 per cent) as V. cholerae 0139. Keeping in mind the unique potential of 0139 among non 01 vibrio to cause epidemics, we decided to undertake the study of biochemical characters and physiological behaviour of all the 44 V. cholerae 0139 isolates. All the stains were Voges Proskauer's test positive' haemagglutinating and grew in the presence of 6 per cent sodium chloride. 13 (29.5 per cent) strains showed haemolytic activity. Nine (20.5 per cent) were polymyxin-B sensitive and 4 (9.0 per cent) fermented lactose. All the isolates showed considerable degree of homogeneity in their biochemical and physiological properties, some characters define them to be closer to El Tor biotype.

Cholera↗
PubMed1995

Role of body surface cultures in prediction of sepsis in a neonatal intensive care unit.

An analysis of surface cultures of 35 preterm infants of less than 33 weeks gestational age hospitalized in a neonatal intensive care unit was made. The babies had received neither antiseptic nor antibiotic therapy prior to collection of specimens. Surface cultures were collected on the 4th or 5th day of life from 16 skin or mucosal sites. At the onset of a febrile episode within 14 days of collection of surface swabs, a blood culture was done on 31 infants (four did not develop fever) and the results were compared with the surface cultures. Sepsis was diagnosed by positive blood culture in twenty neonates (57.1%). With this frequency of sepsis, the optimum sensitivity, specificity and positive predictive values of surface cultures were 60%, 27% and 60%, respectively. These values did not improve substantially for any anatomic site cultured or for any pathogen recovered. We conclude that surface cultures are of limited value in predicting the aetiology of sepsis in neonates.

Bacteria↗
PubMed1995

Nosocomial outbreak of Salmonella typhimurium infection in a nursery intensive care unit (NICU) and paediatric ward.

A nosocomial outbreak of multidrug resistant Salmonella typhimurium in a Nursery Intensive Care Unit (NICU) and Paediatric ward is reported. Eight (16.6%) out of a total of 48 babies taken ill during this outbreak expired. Clinical manifestations included diarrhoea and fever. The organism was isolated from stool samples/rectal swabs of all the 48 cases and blood of 6 cases. An investigation was undertaken to trace the source of infection. The organism was isolated in pure cultures from three suction machines of NICU. The epidemic was immediately controlled with identification of the source but the question of how the suction machines were infected by this organism remained unsolved.

Child, Preschool↗
PubMed1992

Cryptosporidiosis in east Delhi children.

A total of 350 stool samples from children below 3 yrs. of age with diarrhoea (Group I), matched controls (Group II) and persons between age group 4-30 years with diarrhoea (Group III) were examined for cryptosporidium oocysts. Cryptosporidium was detected only in children with diarrhoea. Infection was predominant in males so this study suggests that cryptosporidium is a cause of diarrhoea in children and the necessity of routine laboratory investigation for diagnosis of the condition.

Adolescent↗