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J N Banavalikar

Publications and source records attributed to J N Banavalikar.

4 recordsLinked to original sources

Suspected small-scale interpersonal transmission of Mycobacterium tuberculosis in wards of an urban hospital in Delhi, India.

Genotypes of Mycobacterium tuberculosis causing disease were investigated in pulmonary tuberculosis patients admitted to two adjacent wards of a tuberculosis hospital in Delhi, India. Genetic markers, the insertion sequence IS6110, a direct repeat sequence, and a polymorphic GC-rich sequence supported the circumstantial epidemiologic link between eight strains of M. tuberculosis, suggesting their possible involvement in small-scale, interpersonal transmission of both drug-sensitive and drug-resistant tuberculosis. This is the first report of a suspected acquisition of M. tuberculosis among hospitalized patients in India. The use of multiple molecular typing markers and techniques unequivocally identified the exact clonality of strains isolated from the hospital. The result of this study emphasizes the need for more comprehensive investigation of high-risk situations for tuberculosis transmission and long-term follow-up analysis for identifying such instances of unsuspected transmission.

Cross Infection↗

Dysregulation of homeostasis of blood T-lymphocyte subpopulations persists in chronic multibacillary pulmonary tuberculosis patients refractory to treatment.

DESIGN: The dysregulation of homeostasis of blood-T lymphocyte subpopulations was studied in 21 cases of chronic, multibacillary pulmonary tuberculosis refractory to treatment. The clinico-bacteriological and immunological parameters studied in these cases (Gr A) were compared with those of a group of 10 newly-diagnosed drug sensitive cases of pulmonary tuberculosis (Gr B) at the beginning of the study and after 3 months of chemotherapy for tuberculosis. The chronic cases were treated with drugs selected from a reserve line. 10 normal healthy individuals were included in this study as a control group. RESULTS: At the beginning of the study the mean CD4/CD8 lymphocyte ratios in the refractory cases (0.69) and the newly diagnosed cases (0.81) were significantly lower than those of the normal control subjects (1.84). After 3 months of chemotherapy all but 3 of the newly-diagnosed cases showed clinical improvement, and all became sputum-negative. Their CD4/CD8 ratio recorded a rise to near normal (1.54). On the contrary, following 3 months of reserve-line regimen, only 7 of the 21 group A cases showed sputum conversion. In all of the refractory cases, irrespective of sputum conversion, the CD4/CD8 ratio remained low (1.05). CONCLUSION: This probably indicates that due to a long-standing bacillary load in drug resistant pulmonary tuberculosis patients the dysregulation of homeostasis of blood-T lymphocytes becomes persistent. This in turn delays their clinical and immunological recovery, even when therapy is adequate.

Adolescent↗

Peripheral blood T lymphocyte subpopulations in patients with tuberculosis and the effect of chemotherapy.

Peripheral blood T lymphocytes and their subsets were determined in 30 patients with pulmonary tuberculosis (15 smear positive and 15 smear negative) and 11 healthy individuals. All patients were assessed clinically, radiologically, bacteriologically and by tuberculin testing, and their lymphocyte counts were repeated after completion of 3 months chemotherapy. The mean ratio of putative helper/suppressor T cell subsets (CD4/CD8) of healthy individuals was 1.8 (range 1.1-2.5). These ratios were independent of tuberculin reactivity and were unaffected by BCG vaccination. In both smear positive and smear negative patients there was a reduction in the total T cell and CD4 counts and an increase in the CD8 count, with a concomitant reduction in the CD4/CD8 ratio. Following successful chemotherapy, the mean CD4/CD8 ratios reverted from 0.82 to 1.57 in smear positive patients and 0.88 to 1.52 in smear negative patients, these being near normal values.

Adolescent↗