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S S Grover

Publications and source records attributed to S S Grover.

17 recordsLinked to original sources
PubMed2006

Phenotypic and genotypic detection of ESBL mediated cephalosporin resistance in Klebsiella pneumoniae: emergence of high resistance against cefepime, the fourth generation cephalosporin.

OBJECTIVES: Cephalosporins belonging to second and third generation are commonly used in India for the treatment of Klebsiella pneumoniae. Report on resistance among K. pneumoniae strains to second and third generation cephalosporins are on rise in this country, which has been attributed to emergence of strains expressing extended-spectrum beta-lactamases (ESBLs). The aim of this study was to evaluate the in vitro susceptibility of K. pneumoniae to broad-spectrum cephalosporins particularly to cefepime, a recently introduced fourth generation cephalosporin in relation to ESBL production. METHODS: This study has been carried out in two phases among K. pneumoniae strains isolated between October 2001 and September 2002 (phase I, before marketing of cefepime in India) and between August 2003 and July 2004 (phase II, after marketing of cefepime in India). Minimum Inhibitory Concentration (MIC) was determined by a commercial strip containing gradient of antimicrobials (Strip E-test). Detection for ESBL production was carried out by DDST, E-test ESBL and PCR. RESULTS: Antimicrobial resistance profile of K. pneumoniae strains to five cephalosporins as analyzed by WHONET 5 identified 15 different resistance profiles among the 108 phase I isolates, ranging from resistance to none (19.44%) to all the five cephalosporin (8.33%) and eight different resistance profiles among the 99 phase II isolates, ranging from resistance to none (9.1%) to all the five cephalosporins (36.4%). Among the 108 phase I isolates a total of 71 (65.72%) and out of 99 phase II isolates, a total of 87 (88.0%) could be identified as ESBL producers. Among the isolates, regardless of the phase of the isolation, those characterized by production of ESBL showed overall higher frequency of resistance to cephalosporins (range 19.7-85.9% and 51.7-100% in phase I and phase II, respectively) compared to those for ESBL non-producers (range 0-13.5% and 0-25% in phase I and phase II, respectively). Ten randomly selected isolates from the most common resistance phenotypes probably belonged to a single strain as evident by MIC patterns, genotypic characterization and resistance profile to non-cephalosporin group of antimicrobials thereby pointing out the possibility of an outbreak. CONCLUSIONS: PCR may be regarded as a reliable method for detection of ESBL since in addition to the strains that could be identified as ESBL producers by DDST and E-test ESBL; PCR could demonstrate ESBL production among additional 32 strains (15 in phase I and 17 in phase II). Continued uses of cephalosporin group appear to be a potential risk factor for emergence of ESBL producing K. pneumoniae strains. In addition, as noted in the present study, the rise of resistance to cefepime that has been introduced recently in this country for therapeutic use could be of concern.

Anti-Bacterial Agents↗
PubMed2005

Sensitivity index of antimicrobial agents as a simple solution for multidrug resistance in Salmonella Typhi.

BACKGROUND & OBJECTIVE: Multi drug-resistant (MDR) typhoid in India is an escalating problem. MDR isolates of Salmonella Typhi are on rise and are becoming a challenge for timely and appropriate treatment. Occurrence of per cent sensitive (%S), per cent resistant (%R) and per cent intermediate (%I) isolates may vary geographically and treatment decided on the basis of only one of these three subpopulations may lead to selection of inappropriate drug for treatment and thus treatment failure. Determination of sensitivity index (SI) of antimicrobial agents, instead of %S or %R subpopulations, may give clearer insight regarding selection of appropriate antimicrobial for treatment of typhoid. In present work, the data of sensitivity testing were analysed and interpreted both in terms of SI as well as %S, %I and %R. METHODS: A total of 205 isolates of Salmonella Typhi were collected during June 2000 and August 2002 from a network of five institutes- Lady Hardinge Medical College (LHMC, N=110), Ram Manohar Lohia Hospital (RML, N=14), Majeedia Hospital (MH, N=48), Lal's Pathology Lab (LAL, N=28) and All India Institute of Medical Sciences (AIIMS, N=5) on nutrient agar slopes. Of these, 142 isolates were subjected to phage typing and biotyping at National Salmonella Phage Typing Centre, New Delhi. Five isolates resistant to 3-7 and one isolate susceptible to all of total 12 antimicrobial tested were subjected to plasmid analysis. SI for various antimicrobials was determined as the ratio of %S and %R values derived form %RIS analysis using WHONET5. RESULTS: 18 (8.7%) isolates were susceptible to all tested antimicrobials and 124 (60%) were MDR. Of the 142 isolates, 103 were phage type E1 and biotype I. SI of antimicrobials rather than individual %S or %R or %I population presents a better criterion for interpretation of sensitivity testing data as well as selection of the most appropriate antimicrobial for timely treatment. Presence of 140, 48 and 23 Kb size plasmids in all 5 MDR isolates and none in susceptible isolate was observed. INTERPRETATION & CONCLUSION: Re-emergence of chloramphenicol sensitivity in Salmonella typhi was observed in the present study. Interpretation in terms of SI criteria warrants that reintroduction of chloramphenicol at present for treatment of typhoid may rebound resistance. Current empiric therapy used for treatment of typhoid may soon become ineffective. SI being a ratio will not only eliminate geographical variation of %RIS data but also its interpretation. SI can provide guidelines for clinicians in remote areas where facilities for sensitivity testing are not available.

Drug Resistance, Multiple, Bacterial↗
PubMed2004

Antimicrobial susceptibility pattern and prevalence of extended spectrum beta-lactamase (ESBLs) producing strains of Klebsiella pneumoniae from a major hospital in New Delhi.

Extended spectrum beta-lactamases (ESBLs) are plasmid mediated enzymes capable of hydrolyzing penicillins, broad spectrum-cephalosporins and monobactams. The ESBL producing K. pneumoniae strains are being reported from around the world including India. The present study was taken up to evaluate the ESBL production and in-vitro susceptibility of K. pneumoniae isolates from a hospital. The bacterial isolates collected during 2003 included 51 K. pneumoniae biochemically confirmed isolates from 395 patients admitted in various wards of a major hospital in New Delhi. The isolates were from pus, wound, pleural fluid, urine and tracheal aspirate of patients attending respiratory, urology and burns wards. Antimicrobial susceptibility was carried out by Kirby Bauer's disc diffusion technique using NCCLS criteria. A screening of ESBL production was done by Double-disc synergy test (DDST) and using E-test ESBL strips. The frequency of resistance among K. pneumoniae for the cephalosporins (cefoxitin, cefuroxime, cefotaxime, ceftazidime, and cefepime) and non-cephalosporins (aztreonam, piperacillin, chloramphenicol and trimethoprim-sulfamethoxazole) were in the range of 39.2-88.0% and 51.0-90.2% respectively. 14 different antimicrobial resistance profiles were recognized ranging from resistance to only four (n=6, 11.7%) to as many as ten (n=9, 17.7%). Among the 51 isolates of K. pneumoniae strains, a total of 36 (70.6%) could be identified as ESBL producers, that correlates with the high frequency of multi-drug resistant K. pneumoniae The study shows alarming rise in ESBL production among K. pneumoniae strains and high rate of resistance to a wide range of cephalosporin and non-cephalosporin group of antimicrobials.

Anti-Bacterial Agents↗
PubMed2003

Immune response in HIV-1-infected children with thalassaemia given a primary course of DPT vaccine before acquiring HIV-1 infection.

The effect of HIV infection on immune response to diphtheria and tetanus primary immunisation was investigated in 24 HIV-1-positive multi-transfused (MT) children with thalassaemia and compared with 48 HIV-1-negative MT thalassaemic children and 36 HIV-1-negative non-transfused (NT) children in the community. Diphtheria and tetanus antibody levels in the HIV-1-positive MT group were comparable with the two HIV-negative groups. The proportions of children with antibody titres below the protective level (i.e. <0.01 IU/ml) for antidiphtheria antibodies were 20.8, 16.6 and 16.6%, and 12.5, 12.5 and 13.9% for anti-tetanus antibodies in the three groups, respectively. On the other hand, delayed-type hypersensitivity (DTH) response to diphtheria and tetanus antigens was significantly depressed in the HIV-1-positive group compared with the HIV-negative controls. The mean percentages of both mature (CD20+) and immature (CD10+) B-cell counts were significantly higher in the HIV-1-positive group than in the HIV-negative MT and NT groups (p<0.05). Levels of serum immunoglobulins and spontaneously secreted immunoglobulins were significantly higher in the HIV-1-positive group compared with both HIV-negative groups. The HIV-1-positive group showed a mean (SD) IL-6 of 52.9 (28.8) pg/ml compared with 23.7 (12.1) pg/ml and a detection rate of 54.2% in the HIV-negative MT group, and 23.6 (8.2) pg/ml and a 50% detection rate in the HIV-negative NT group. The IL-2 level was significantly lower (p<0.05) in the HIV-1-positive group [41.7% detection rate and mean (SD) 28.8 (17.1) pg/ml] than in the HIV-negative MT and NT groups [75% and 83.3% detection rates and mean (SD) 57.2 (42.3) pg/ml and 99.3 (51.1) pg/ml, respectively]. During follow-up for 3 years, the frequency of major infections was significantly higher in the HIV-1-positive group than in the other two groups. Acute pneumonia and acute sinusitis were the predominant infections regardless of HIV status while primary bacteraemia, osteomyelitis, pyogenic meningitis and septic arthritis were common in the HIV-1-positive group. We conclude that, in HIV-1-infected children pre-immunised with DPT, DTH response to diphtheria and tetanus antigens might be more reliable than anti-diphtheria and anti-tetanus antibody levels in predicting susceptibility to major bacterial infections.

Adolescent↗
PubMed2000

Evaluation of oxidative stress in some cases of argimone oil poisoning during a recent outbreak of epidemic dropsy in India.

The study was designed to evaluate the oxidative stress and modulation of anti-oxidant enzymes in 10 accidental argimone oil poisoning cases admitted in a hospital in Delhi, India during a recent outbreak of epidemic dropsy in 1998. Serum malondialdehyde (MDA) level, oxygen free-radical scavenging enzymes such as superoxide dismutase (SOD) and catalase (CAT), and glutathione (GSH) and related enzymes, e.g. glutathione reductase (GR), glutathione peroxidase (GPx), gamma glutamyl transpeptidase (GGT) and glutathione-S-transferase (GST) in erythrocytes were assayed. The sanguinarine level in serum was measured by high-performance liquid chromatography. The serum MDA level was higher and the GSH level in erythrocytes was lower in argimone oil poisoning cases than those in controls. There was a significant decrease in SOD and GPx activities in erythrocytes of epidemic dropsy cases but no changes were observed in CAT, GR and GST assay. The depletion of GSH in erythrocytes, serum MDA level and clinical severity were dependent on serum sanguinarine level. The results indicate that sanguinarine (argimone oil) poisoning creates an oxidative stress in humans. The oxidative stress and differential modulation of anti-oxidant enzymes by sanguinarine might play a pathogenic role in epidemic dropsy, which suggests the incorporation of anti-oxidant drugs in the treatment protocol of the disease.

Chromatography, High Pressure Liquid↗
PubMed1997

Transplacental dilution of tetanus antitoxins in Delhi.

Maternal blood-cord samples from 171 women of middle socio-economic status who had been administered at least two doses of tetanus toxoid (TT), were assayed for tetanus antitoxins by passive haemagglutination (PHA) test. All the mother as well as cord samples had antitoxin titres > or = 0.015IU/ml, the generally accepted minimal protective level; 98 per cent of the mothers and 97 per cent of the newborns had levels > or = 0.125IU/ml. Transplacental dilution was observed in 45 per cent of the samples; the cord/maternal antitoxin ratio (C/M) of geometric mean titre (GMT) was found to be 0.72. The C/M ratio was not affected by the maternal age, parity, birth weight, and number of TT doses administered to mother. The study showed that tetanus antitoxins were diluted on the fetal side of circulation, but the protective levels of antitoxins were achieved in all the newborns as the mothers had received at least two doses of TT before delivery.

Adolescent↗
PubMed1993

Prevalence of diphtheria and tetanus antibodies in young adults in Delhi.

A total of 574 blood samples collected mainly from adult males, on a random basis, were tested for diphtheria and tetanus antibodies by Indirect Haemagglutination (IHA) test to find out the percentage of individuals with protective titres (> or = 0.015 IU/ml). A total of 502 (87.5 per cent) and 437 (76.2 per cent) of these had protective titres against diphtheria and tetanus respectively. The vaccination status of these subjects against diphtheria and tetanus was not ascertainable. The relevance of these findings is discussed.

Adult↗
PubMed1990

Nasopharyngeal carriage of Neisseria meningitidis in general population and meningococcal disease.

Nasopharyngeal carriage of Neisseria meningitidis was determined in the normal healthy population in Delhi at monthly intervals for a period of 2 years from January, 1986 to December, 1987. Of a total of 6513 individuals screened only 107 (1.64 per cent) were found to carry Neisseria meningitidis serogroup A. There was no age and sex difference in carriage. During the same period, data of laboratory confirmed cases of meningitis due to N. meningitidis serogroup A was obtained from 6 hospitals of Delhi which acted as sentinel centres. Of the total 11,870 pyogenic C.S.F. samples processed, only 557 (4.69 per cent) were due to N. meningitidis serogroup A. There was no correlation observed between the nasopharyngeal meningococcal carriage in the healthy population with the disease prevalence. There was no seasonal variation in nasopharyngeal carriage though upsurge in the number of meningococcal meningitis cases was noticed from January to April.

Adolescent↗