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Biomedical subjects

T D Chugh

Publications and source records attributed to T D Chugh.

At least 37 records · Page 2Linked to original sources
PubMed1996

Molecular characterization of epidemic ciprofloxacin- and methicillin-resistant Staphylococcus aureus strains colonizing patients in an intensive care unit.

Eighteen methicillin-resistant Staphylococcus aureus (MRSA) samples isolated from patients and the environment in an intensive care unit (ICU) during a routine surveillance were tested for antimicrobial resistance and typed by pulsed-field gel electrophoresis. Three pulsed-field patterns were observed. Sixteen were ciprofloxacin resistant and had identical pulsed-field patterns. The results suggested that a ciprofloxacin-resistant MRSA clone had contaminated the environment and spread among patients. This study demonstrates the application of infection control surveillance combined with strain typing in detecting MRSA colonization in the ICU where it was not known to exist.

Anti-Infective Agents↗
PubMed1996

Nocardiosis in renal transplant recipients in Kuwait.

BACKGROUND: Nocardiosis has emerged as an important bacterial disease among renal transplant recipients, leading to considerable morbidity and mortality. Apart from the increasing problem of resistance in pathogenic nocardiae, the spectrum of species causing disease has enlarged in recent years. There are no published reports on nocardiosis from Middle-East countries. METHODS: A retrospective review of case records of 513 renal transplant recipients between January 1989 and January 1995 was done in the transplant unit of our hospital. Information was collected on clinical details, type of donor, immunosuppressive therapy, prophylaxis, and outcome. Isolation of Nocardia species from appropriate clinical specimens was the sole criterion for diagnosis. RESULTS: Nocardiosis was diagnosed in six recipients with a disease incidence of 1.2%. Four patients had received unrelated kidneys. Co-morbid conditions were diabetes mellitus (3), viral hepatitis (2) and neutropenia (1). Clinical manifestations included deep-seated skin abscesses and pulmonary disease in three each. Cerebral abscess and meningitis were found in two patients with pulmonary disease. Pathogens were Nocardia asteroides in four and N. otiti discaviarum and N. farcinica in one each. In contrast to in vitro susceptibility results, clinical response was different in that five patients who received trimethoprim-sulphamethoxazole (TMP-SMX) alone (2) or in combination with cefuroxime (3) responded well. CONCLUSIONS: The study stresses a high index of suspicion for nocardiosis in susceptible hosts who present with cutaneous abscess, pulmonary infiltrative lesions, and cerebral manifestations. TMP-SMX in combination with cefuroxime seems to be a highly effective therapy. It does not appear mandatory to reduce or discontinue immunosuppressive therapy during treatment of nocardiosis.

Adult↗
PubMed1995

Establishment and evaluation of a multiplex polymerase chain reaction for detection of mycobacteria and specific identification of Mycobacterium tuberculosis complex.

OBJECTIVE: To establish a multiplex polymerase chain reaction for detection of mycobacteria and specific identification of Mycobacterium tuberculosis complex and to evaluate the test in the diagnosis of tuberculosis. DESIGN: Three sets of primers were used to amplify 383 bp, 240 bp and 131 bp DNA fragments from the genes encoding the 65 kDa, MPB64 and the 19 kDa proteins of M. tuberculosis in a single reaction tube. Reaction conditions were optimized with respect to the requirement of DMSO, concentration of MgCl2, annealing and denaturation temperatures and number of amplification cycles. Inhibitory activity in clinical samples was identified by amplifying a 500 bp DNA fragment of the phage lambda along with the mycobacterial targets within the same reaction tube. The multiplex PCR was evaluated in differentiating M. tuberculosis complex from other mycobacteria and in the diagnosis of tuberculosis by testing clinical specimens. RESULTS: Amplification of the 383 bp DNA fragments was specific to the genus Mycobacterium. The 240 bp DNA fragment was amplified from M. tuberculosis complex and M. fortuitum and the 131 bp DNA fragment was amplified from the mycobacteria of M. tuberculosis complex and M. scrofulaceum. All the three bands were amplified only from M. tuberculosis complex. Applicability of the multiplex PCR is demonstrated in differentiating M. tuberculosis complex from other mycobacteria by using standard strains and clinical isolates. The multiplex PCR was also useful in the detection of inhibitory activity and in the identification of M. tuberculosis complex directly in clinical samples. CONCLUSION: The multiplex PCR established in this study could differentiate M. tuberculosis complex from other mycobacteria. This test may also be helpful in the early and specific diagnosis of tuberculosis.

Bacterial Typing Techniques↗
PubMed1995

Antimicrobial resistance of coagulase-negative staphylococci from a Kuwait hospital.

This study investigated the incidence of antimicrobial resistance in clinically significant coagulase-negative staphylococci at the Mubarak Al Kabeer Hospital, Kuwait. A total of 104 isolates of coagulase-negative staphylococci consisting of S. epidermidis (67), S. haemolyticus (16), S. saprophyticus (6), S. simulans (2), S. hominis (4), S. albus (2), S. sciuri (3), S. warneri (2), S. capitis (1), and S. xylosus (1) were isolated from clinical specimens over a 6-7 month period and tested for resistance to 22 antibacterial agents and the ability to produce slime. They were all susceptible to vancomycin and mupirocin but intermediate resistance to teicoplanin was detected in seven isolates: 83 and 47.7% were resistant to penicillin G and methicillin, respectively, 57% were resistant to gentamicin, 49.5% to erythromycin, 50.4% to tetracycline, and 52.3% to trimethoprim. Resistance to heavy metals and the nucleic-acid binding compound was also detected. More than half of S. epidermidis, S. saprophyticus, S. simulans, S. hominis, and all of S. haemolyticus were multiply resistant to three or more groups of antibiotics and there was a significant association between slime production and resistance to multiple antimicrobial agents in S. epidermidis. The results revealed a high level of resistance to commonly used agents.

Anti-Bacterial Agents↗
PubMed1995

Renal aspergilloma due to Aspergillus flavus.

Renal aspergillomas have been reported only rarely. We report a case of Aspergillus flavus colonization of the renal pelvis and upper ureter of a patient with concomitant urinary schistosomiasis. The diagnosis was based on the demonstration of characteristic hyphal elements on direct microscopy and isolation of the fungus in culture. The patient was successfully treated with liposomal amphotericin B. This case emphasizes the importance of direct microscopic examination of urine specimens for prompt diagnosis of fungal infections of the urogenital system. Renal aspergilloma should be considered in the differential diagnosis of filling defects of the urinary tract, especially in patients who are immunocompromised.

Adult↗
PubMed1994

An outbreak of multidrug resistant Salmonella typhimurium in Delhi (India).

A total of 85 patients with multidrug resistant S. typhimurium were isolated between May and September 1991 at the Sir Ganga Ram Hospital, New Delhi, India. Fifty eight (72.5%) patients out of 80 stool culture positives suffered from enteritis and 23 (39.6%) of them settled with oral rehydration therapy alone. All strains were sensitive to 4 aminoquinolones (oflaxcin) but five were resistant to third generation cephalosporin (Cefotaxime; MIC between 50-75 micrograms/ml) whereas 88-96 per cent isolated were resistant to most of the other antibiotics. The convalescent carrier rate was prolonged with the use of antibiotics. The phage type of S. typhimurium isolated from the index and other cases was 178 and multidrug resistance strains had seven plasmids (1.2 to 16 kb). Barrier nursing and sodium hypochlorite disinfection helped in limiting the outbreak.

Adult↗
PubMed1990

An investigation of patients with pulmonary tuberculosis in Kuwait in preparation for studies of immunotherapy with Mycobacterium vaccae.

Sixty-five patients, many of them immigrant to Kuwait, with bacteriologically proven, adult type, pulmonary tuberculosis were studied by many parameters over the 4 months following diagnosis. Twelve were infected with tubercle bacilli resistant to at least one anti-tuberculosis drug. Preliminary evidence suggested that this was frequently primary resistance in patients infected in their countries of origin. The Kuwaiti environment results in very high skin test and lymphocyte proliferative responses (LTT) to shared and species specific antigens of mycobacteria in healthy persons. In comparison, patients with tuberculosis lacked cellular responses to group i and group ii antigens, but had increased IgG and IgA binding to mycobacterial antigens in general. LTT responses to added interleukin 2, and production of alpha interferon, were normal in our patients, but induction of gamma interferon in response to phytohaemagglutinin was reduced initially, rising towards normal during treatment. Biochemical and haematological abnormalities present at the time of diagnosis rapidly corrected. The disease differed from that reported in most previous studies in that fever was uncommon, the disease was never fatal, and most tuberculin tests were not necrotising. This implied that a detrimental immunopathological component is less pronounced in those exposed to the Kuwaiti environment, and a hypothesis is put forward to explain this.

Adolescent↗
PubMed1990

Immunotherapy with Mycobacterium vaccae as an adjunct to chemotherapy in the treatment of pulmonary tuberculosis.

47 patients with adult-type pulmonary tuberculosis attending the Chest Diseases Hospital in Kuwait were given a single injection of 10(9) irradiation-killed M. vaccae after 1 month of a 9-month course of chemotherapy. The patients were followed-up for 3 more months in double blind comparison with 65 patients given an injection of saline (placebo). The immunotherapeutic injection produced a small local lesion in 44/47 patients, 18 of which ulcerated and produced small scars. Immunotherapy made no measurable difference to the bacteriological, biochemical, haematological, or radiological parameters measured. However it was associated with significantly improved weight gain, reduced size of skin test response to Tuberculin, increased lymphocyte proliferation to common mycobacterial antigens, and increased antibody levels to mycobacterial antigens. The changes in skin test and LTT responses were related and occurred in 29% of patients whose recognition of common mycobacterial antigens returned to normal. The remaining patients did not differ in these respects from those receiving placebo. The proportion of patients whose responses were improved was very similar to that achieved using the same immunotherapeutic agent in a group of treated multibacillary leprosy patients.

Adolescent↗
PubMed1990

Improved immunotherapy for pulmonary tuberculosis with Mycobacterium vaccae.

We previously demonstrated that a single intradermal injection of 10(9) irradiation-killed M. vaccae, given 1 month after starting chemotherapy, caused significant changes in responses to mycobacterial antigens. Amongst 38 patients with pulmonary tuberculosis, 29% had lymphocytes responding to common myocobacterial antigens after the injection, compared with only 11% of 49 similar patients after an injection of saline (p less than 0.03). To increase the proportion of responders to these antigens, six modifications of the potentially immunotherapeutic injection, randomized with injections of saline, have been assessed by biochemical, clinical, haematological, immunological and radiological criteria. Subsequent lymphocyte proliferation to mycobacterial antigens enabled the modifications to be ranked in order of efficacy. Tuberculin plus murabutide plus 10(9) irradiated M. vaccae (36% of 25), an autoclaved preparation of 10(9) M. vaccae (45% of 22), and 2 x 10(9) irradiated M. vaccae (75% of 12) were the most effective. Antibody responses in several IgG subclasses to mycobacteria, but not streptococci, were also significantly increased by the most effective modifications over the 8 weeks following injection. Detailed radiological study showed that use of the autoclaved bacilli was followed by a delay in clearing of consolidation, but by better closing of cavities than was found in the control group, suggesting enhanced, or altered, immunological activity around the lesions.

Acetylmuramyl-Alanyl-Isoglutamine↗
PubMed1990

Adherence of Staphylococcus epidermidis to fibrin-platelet clots in vitro mediated by lipoteichoic acid.

The adherence of two strains of Staphylococcus epidermidis to human fibrin-platelet clots in vitro was investigated. Both strains were noncapsulated, nonhemagglutinating, and nonslime producers. Binding was not related to surface charge, carbohydrate profile, or hydrophobicity of the bacteria. Adherence was reduced four- to sixfold (P less than 0.001) on pretreatment of bacteria with lipase, while neuraminidase, trypsin, phospholipase C, and sodium periodate did not alter their binding. Pretreatment of bacteria with substances known to bind lipoteichoic acid (LTA), such as human albumin and anti-LTA antibodies, also resulted in a fourfold (P less than 0.001) reduction in adherence. Prior incubation of clots with free LTA, but not with deacylated LTA, produced a fourfold (P less than 0.001) decrease in the adherence of homologous and heterologous strains of S. epidermidis. A similar reduction was also observed when LTAs derived from Staphylococcus aureus and Streptococcus pyogenes were used. These data provide evidence that the lipid moiety of LTA has a central role in the adherence of S. epidermidis to fibrin-platelet clots in vitro.

Bacterial Adhesion↗
PubMed1989

HLA-DR and tuberculin tests in rheumatoid arthritis and tuberculosis.

Responses to four new tuberculins were found to be significantly reduced in 46 patients with rheumatoid arthritis in comparison with a control group of 79. Except for tuberculin itself, the same was found in 111 patients with tuberculosis. In common with patients with tuberculosis and leprosy, those with rheumatoid arthritis did not respond to common mycobacterial (group i) antigen. Three DR haplotypes were found to have significant effects on skin test responsiveness of the rheumatoid patients but had little or no effect on that of the patients with tuberculosis and none on that of the healthy control group. Rheumatoid patients with the HLA-DR4 haplotype had significantly greater responses to all four reagents than did non-DR4 patients, but their responses to leprosin A and scrofulin remained significantly lower than those of the control group. Possession of HLA-DR3 haplotype was associated with skin test positivity approaching normal, but the sizes of responses were reduced. Possession of DR7 was associated with an unexpected reduction in skin test positivity, especially in the case of tuberculin. These results support the hypothesis that mycobacteria, or autoantigens cross reactive with mycobacteria, may be involved in the aetiology of rheumatoid arthritis. The results also show that the regulation and specificity of responsiveness to mycobacterial antigens are different in patients with rheumatoid arthritis with different HLA-DR haplotypes.

Adolescent↗
PubMed1989

Effect of sublethal concentration of antibiotics on the adherence of Staphylococcus epidermidis to eukaryotic cells.

Adherence of Staphylococcus epidermidis to pharyngeal epithelial cells as measured by [3H]-leucine-labelled bacteria was found to be a simple, objective and highly reproducible technique. Sublethal concentrations of cephalothin, rifampicin and vancomycin significantly reduced the bacterial adherence to epithelial cells, the effect being most marked with 1/2 MIC. Cloxacillin increased the adherence for one strain while it decreased it for the second. The effect was dose-related and the maximum reduction was observed when bacteria were grown with an antibiotic overnight.

Animals↗
PubMed1988

Comparative study of culture, direct immunofluorescent antibody test and enzyme immunoassay for the diagnosis of urogenital infections caused by Chlamydia trachomatis.

We studied three population groups (161 symptomatic female, 62 asymptomatic female and 74 symptomatic male) to determine the prevalence of genital tract infections caused by Chlamydia trachomatis in Kuwait. Three techniques, viz. tissue culture, direct immunofluorescent antibody test (MicroTrak) and enzyme immunoassay (Chlamydiazyme) were employed for the detection of C. trachomatis. The overall positivity based on positive tissue culture in symptomatic cases was 16.2% (17.4% in female and 13.5% in male). The two rapid methods for antigen detection were compared with tissue culture. Based on a positivity criterion of greater than 10 elementary bodies in the direct immunofluorescent antibody assay, sensitivity and specificity of the test were 66.7% and 97.2% while the positive and negative predictive values were 77.8% and 97.2% respectively. The sensitivity and specificity of the enzyme immunoassay were 61.3% and 96.7% with positive and negative predictive values of 80.8% and 94.6% respectively. There was an agreement of 92.0% between the three tests. The two rapid antigen detection tests seem to be similar and provide an alternative for diagnosing Chlamydia trachomatis in our patients.

Cells, Cultured↗
PubMed1988

A comparison of antibiotics consumption and bacterial resistance patterns in Kuwait and Sweden.

The total utilization of antimicrobial drugs, expressed as DDD/1000 inhibitants/day, was 19 in Kuwait and 15 in Sweden. Aminoglycosides, tetracyclines and trimethoprim/sulphonamide were used more in Kuwait than in Sweden. The utilization of cephalosporins, however, was more prevalent in Sweden than in Kuwait. Hospital use of aminoglycosides was more pronounced in Kuwait than in Sweden, whereas trimethoprim/sulphonamide was less utilized in Kuwait. The overall consumption of antimicrobial drugs expressed as DDD/500 hospital beds, was highest in one of the Swedish hospitals where, for example, the consumption of tetracyclines was 15-fold higher than that in the comparable Kuwaiti hospital. Regarding bacterial resistance patterns, the large use of aminoglycosides and ampicillin was reflected in a higher resistance frequency among the Kuwaiti isolates. Resistance frequencies for trimethoprim/sulphonamide was also relatively much higher in Kuwait than in Sweden. In this case there was, however, no simple correlation to utilization figures, which are lower for the Kuwaiti hospital than for the Swedish. Resistance to chloramphenicol was prevalent in both countries, in spite of the very limited use of this drug.

Anti-Bacterial Agents↗
PubMed1987

Unexpected findings amongst the skin test responses to mycobacteria of BCG vaccinated Kuwaiti school children.

A multiple skin test survey was carried out in Kuwait on 1200 school children aged 8-11 years, and on 1228 children aged 12-16 years. With only 15 exceptions, all these children had received vaccination with Japanese BCG just before they started school, 5 years and 9 years earlier respectively. Tuberculin positivity was almost 90% in both groups, with a mean response size of 8.7 mm. This was associated with remarkably high responsiveness to many of the other mycobacterial species investigated. Since this high reactivity was also to Mycobacterium ulcerans, a species most unlikely to be present in Kuwait, it is proposed that this might be due to responsiveness to group ii antigen which is present in all slow growing species. Only M. flavescens and M. rhodesiae amongst the fast growing species, were absent as sensitising organisms. After correction for the supposed reactivity to group ii antigen, M. avium B, M. gordonae, M. ulcerans and M. xenopi amongst the slow growing species, also appeared to be absent from the Kuwait environment. The species most commonly encountered were M. leprae, M. chitae, M. neoaurum, M. diernhoferi, and M. vaccae in this order. This was a remarkable finding for a country assumed to be poor in contact with environmental species, and known to have a very low prevalence of leprosy. As previously reported from Iran, but not confirmed in other places, there was a 95% correlation between responsiveness to Leprosin A and Vaccin. Amongst the slow growing species M. avium A, M. intracellulare, and M. kansasii appear to be frequent sensitising agents, in common with many other places.

Adolescent↗
PubMed1987

Characterization of self-transmissible plasmids determining lactose fermentation and multiple antibiotic resistance in clinical strains of Klebsiella pneumoniae.

The lactose fermentation (Lac+) and antibiotic resistance (R+) phenotypes were conjugally transferred from Klebsiella pneumoniae strains (K166, K182, K186, K218, and K220) to Salmonella typhi, S. typhimurium, Shigella flexneri, and Vibrio cholerae. The genes for lactose fermentation and antibiotic resistance were located on the plasmids. Further analysis of plasmid DNA from these isolates indicated the presence of multiple plasmids (Mr ranged less than 2.7 to 70 X 10(6)). The Lac+R+ plasmids p166 and p182 were members of the FII incompatibility group. The fertility inhibition property of plasmids, p182, p218, and p220 was fi+ type. Furthermore, phage typing experiments showed that plasmids p166 and p218 (Lac+R+) conferred the ability to inhibit the multiplication of bacteriophages 12 and 13 in S. typhimurium. However, the plasmids p182, p186, and p220 (Lac+R+) could inhibit the visible lysis of all the 30 phages in S. typhimurium. This study describes the characterization of Lac+R+ plasmids and the medical significance of an intergeneric transfer of lactose fermentation to non-lactose-fermenting pathogens.

Escherichia coli↗
PubMed1987

Detection of Salmonella spp. in clinical specimens by capture enzyme-linked immunosorbent assay.

A capture enzyme-linked immunosorbent assay (ELISA; Kirkegaard and Perry Laboratories, Gaithersburg, Md.) was used to detect Salmonella spp. in clinical and artificially inoculated specimens. In patients with bacteremia caused by Salmonella spp., 48% (12 of 25) and 82% (13 of 16) of serum and urine specimens, respectively, were positive for Salmonella spp., as determined by ELISA. All serum and urine specimens collected from healthy individuals (25 specimens) or patients whose blood cultures grew gram-negative bacteria other than Salmonella spp. (18 specimens) were negative for Salmonella spp., as determined by ELISA. For blood culture bottles in which Salmonella spp. (16 specimens) was grown the ELISA was positive (100%), while it was negative for all the 65 blood culture bottles in which gram-negative bacteria other than Salmonella spp. (42 specimens) or gram-positive bacteria (23 specimens) were grown. All samples of urine (16 specimens), stool (8 specimens), serum (16 specimens), culture media (12 specimens), and blood culture bottles (reported sterile after 2 weeks of incubation; 16 specimens) that were artificially inoculated with 10(3) to 10(7) CFU of four species of Salmonella per ml were positive by ELISA. Similar specimens inoculated with or containing various species other than Salmonella were negative by this test. Thus, ELISA offers a promising opportunity for the rapid detection of Salmonella spp. in clinical microbiology laboratories.

Antigens, Bacterial↗