A profile of bacteriologically confirmed pulmonary tuberculosis in children.

OBJECTIVE: To describe the clinical profile of children with bacteriologically confirmed tuberculosis. STUDY DESIGN: A multicentric study was conducted in three hospitals in Chennai city between July 1995 and December 1997. Children aged 6 months to 12 years with signs and symptoms suggestive of tuberculosis were investigated further. Clinical examination, chest radiograph, tuberculin skin test with 1 TU PPD and, sputum or gastric lavage for mycobacterial smear and culture were done for all and, lymph node biopsy when necessary. RESULTS: A total of 2652 children were registered and tuberculosis was bacteriologically confirmed in 201. Predominant symptoms were history of an insidious illness (49%), fever and cough (47%), loss of weight (41%) and a visible glandular swelling (49%). Respiratory signs were few and 62% were undernourished. Over half the patients with confirmed TB had normal chest X-ray. Abnormal X-ray findings included parenchymal opacities in 47% and hilar or mediastinal lymphadenopathy in 26%. The prevalence of isoniazid resistance was 12.6% and MDR TB 4%. CONCLUSIONS: Children with tuberculosis present with fever and cough of insidious onset. Lymphadenopathy is a common feature even in children with pulmonary TB. A significant proportion of children have normal chest X-rays despite positive gastric aspirate cultures. Drug resistance rates in children mirror the pattern seen in adults in this geographic area.

Operational feasibility of rapid diagnostic kits & blister packs use for malaria control in high transmission areas of Orissa & Chhattisgarh.

BACKGROUND & OBJECTIVE: Early diagnosis and prompt treatment of cases with malaria are two important components of malaria control strategy. The independent assessment of the operational feasibility of rapid diagnostic kits and blister packs for malaria in some selected high transmission areas of Orissa and Chhattisgarh was done with the objectives to assess the knowledge and skills of the paramedical personnel and their acceptability by the paramedical personnel and the community, and to assess improvement in patients' health seeking behaviour. METHODS: The basic information regarding malaria situation, epidemiological divisions, distribution data of rapid diagnostic kits and blister packs, etc., was collected from State and district headquarters. The subcentres from the primary health centres/community health centres were selected on the basis of supply of rapid diagnostic kits and blister packs. The subcentres were visited and health personnel interviewed about their knowledge and skills on the use of rapid diagnostic kits and blister packs. A cross-sectional survey was conducted to assess the public opinion about rapid diagnostic kits and blister packs. RESULTS: We found that the paramedicals were well trained in the use of rapid diagnostic kits and blister pack administration and the acceptance was good by both paramedicals and general public. The compliance rate of radical treatment with blister packs was 100 per cent and no adverse events were reported. INTERPRETATION & CONCLUSION: Our findings showed that rapid diagnostic kits and blister packs under remote and inaccessible highly malarious areas can be introduced that will have significant impact in reducing malaria morbidity and mortality.

Allelic polymorphism in the Plasmodium vivax dihydrofolate reductase gene among Indian field isolates.

In total, 129 Plasmodium vivax isolates from different geographical areas in India were analysed for point mutations in the P. vivax dihydrofolate reductase gene that were associated with pyrimethamine resistance. A gradual increase in the frequency of mutant genotypes was observed from north to south (p <0.0001). In the northern region (Delhi, Panna and Nadiad), the wild-type genotype was most prevalent, while the mutant genotype predominated in the coastal regions of southern India (Navi Mumbai, Goa and Chennai). Isolates from the Car-Nicobar islands showed only mutant genotypes. The differential geographical pattern of mutations may be associated with the transmission pattern.

Split-drug regimens for the treatment of patients with sputum smear-positive pulmonary tuberculosis--a unique approach.

OBJECTIVE: To evaluate the efficacy of split-drug regimens for treatment of patients with sputum smear-positive pulmonary tuberculosis in south India. DESIGN: Randomized controlled clinical trial where eligible patients were randomly allocated to: (i) 2RE(3)HZ(3)(alt)/4RH(2) (split I): rifampicin plus ethambutol given on one day and isoniazid plus pyrazinamide the next day for first 2 months followed by rifampicin plus isoniazid twice weekly for 4 months, or (ii) 3RE(3)HZ(3)(alt)/3RH(2) (split II): similar to regimen 1, except duration was 3 months in each phase, or (iii) 2REHZ(3)/4RH(2) (control): rifampicin, isoniazid, ethambutol and pyrazinamide, given thrice weekly for 2 months followed by isoniazid and rifampicin twice weekly for 4 months. All patients were followed up clinically and bacteriologically every month up to 2 years and every 6 months for up to 5 years. RESULTS: A favourable response (cultures negative for Mycobacterium tuberculosis during the last 2 months of treatment) was observed in 91% of 407 patients in split I, 94% of 415 in split II and 89% of 418 in the control regimen. Ninety-one per cent of 370 patients in split I, 93% of 389 in split II and 90% of 370 in control regimens had quiescent disease at the end of 60 months. Gastrointestinal symptoms were more frequent under the control regimen (P = 0.01). CONCLUSION: Split-drug regimens were as effective as the control regimen in terms of favourable response at the end of treatment and quiescent disease at 5 years, and caused fewer gastrointestinal side-effects.

HLA-DR2 subtypes & immune responses in pulmonary tuberculosis.

BACKGROUND & OBJECTIVES: HLA-DR2 has been shown to be associated with the susceptibility to pulmonary tuberculosis and altered antibody and lymphocyte response in pulmonary tuberculosis. In the present study, the influence of DR2 subtypes on antibody titre and lymphocyte response to Mycobacterium tuberculosis culture filtrate antigens (10 micrograms/ml) was studied in 22 patients with active pulmonary TB (ATB), 50 inactive (cured) TB (ITB) patients and 36 healthy control subjects. METHODS: HLA-DR2 gene was amplified by polymerase chain reaction (PCR) and dot-blotted. Genotyping of DRB1*1501, *1502, *1503, *1601 and *1602 was carried out using sequence specific oligonucleotide probes (SSOPs) and detected by chemiluminescence method. Antibody titre as well as lymphocyte response to M. tuberculosis antigens were measured by enzyme linked immunosorbent assay (ELISA) and lymphocyte transformation test (LTT) respectively. RESULTS: The allele frequency of DRB1*1501 was significantly increased in pulmonary tuberculosis patients as compared to controls (P < 0.05). No marked difference in the antibody titre and lymphocyte response to M. tuberculosis antigens was observed between the DRB1 *1501, *1502 and *1503 positive or negative controls, ATB and ITB patients. DRB1 *1501 and *1502 positive as well as negative ATB patients showed a higher antibody titre as compared to controls and ITB patients. ITB patients with *1502 showed a higher lymphocyte response as compared to *1502 positive controls (P < 0.001) and ATB patients (P < 0.05). Similarly, an increased lymphocyte response was observed in *1501, and *1503 negative ITB patients compared to *1501 and *1503 negative controls and ATB patients. INTERPRETATION & CONCLUSION: The present study revealed that DRB1 *1501 may be associated either alone or with other DR2 alleles, with the susceptibility to pulmonary tuberculosis. None of the DR2 alleles influenced the antibody and lymphocyte response to M. tuberculosis culture filtrate antigens. This suggested that HLA-DR2 gene/gene products as a whole may influence the immune response in pulmonary tuberculosis.

Tumour necrosis factor alpha (-238 and -308) and beta gene polymorphisms in pulmonary tuberculosis: haplotype analysis with HLA-A, B and DR genes.

SETTING: A study of tumour necrosis factor alpha and beta (TNFalpha and beta) gene polymorphism and haplotype analysis with HLA in pulmonary tuberculosis. OBJECTIVE: To determine whether TNFalpha (-238 and -308) and TNFbeta (Nco I polymorphism in intron 2) genes either alone or in combination with human leucocyte antigens (HLA) as haplotypes afford susceptibility or resistance to pulmonary tuberculosis as well as bacteriological relapse of the disease. DESIGN: Tumour necrosis factor alpha -238, -308 (TNFalpha -238, -308) and TNFbeta (Nco I) gene polymorphisms were carried out in HLA-A,B and DR typed pulmonary tuberculosis patients (n=210) and 120 normal healthy control subjects. RESULTS: No difference in the genotype frequencies of TNFalpha-238 and -308 and TNFbeta was seen between control subjects and pulmonary tuberculosis patients. Of the HLA-TNF haplotypes analysed, the infrequent allele (A) of TNFalpha238 was in strong linkage disequilibrium with HLA-A1 (P corrected: Pc=0.001), B17 (Pc<0.0001) and DR7 (Pc=0.01) in control subjects and with B17 (Pc<0.0001) in pulmonary tuberculosis. The infrequent allele 2 of TNFalpha-308 and the infrequent allele 2 of TNFbeta were in strong linkage disequilibrium with HLA-B21. An increased haplotype frequency of HLA-B17-TNFalpha-238/A (P=0.05), B17-TNFalpha308/2 (P=0.03) and B17-TNFalpha308/2 (P=0.01) was observed in bacteriological relapse patients than quiescent patients. CONCLUSION: The present study suggests that TNFalpha (-238 and -308) and TNFbeta gene variants are not associated independently with the susceptibility to pulmonary tuberculosis. However, in combination with the HLA genes/gene products such as HLA-A1, B17, B21 and DR7, the TNFalpha and beta genes as haplotypes are associated with protection against the disease as well as an increased susceptibility to bacteriological relapse.

Pulmonary function in normal south Indian children aged 7 to 19 years.

There are only a few studies that have established reference standards for pulmonary function of Indian children. Reference standards for pulmonary function that are reported for Indian children are mainly from northern and western parts of the country and there is a paucity of data on pulmonary function in normal South Indian children. Therefore, pulmonary function tests (spirometry and maximal expiratory flow rates) were carried out in 469 South Indian healthy children (246 boys and 223 girls) between 7-19 years of age to derive regression equations to predict pulmonary function. The correlations of forced vital capacity (FVC) and forced expiratory volume in one second (FEV1) were, in general highest with height followed by weight and age. Peak expiratory flow rate (PEFR), forced mid-expiratory flow (FMF) and forced expiratory flow rates at 25%, 50% and 75% of FVC (FEF25% FVC, FEF50%FVC and FEF75%FVC) were also significantly correlated with physical characteristics (age, height and weight). With a view to find out regression equations to predict spirometric functions based on physical characteristics (age, height and/or weight), the functions were regressed over all possible combinations of regressor variables, i.e. age, height and weight separately for boys and girls. The height influences the prediction equation in males to a great extent, whereas age and weight had greater influence in girls. Regression equations were derived for boys and girls for predicting normal pulmonary functions for children in South India. The pulmonary function measurements in South Indian children were similar to those reported for subjects from Western India and lower than those reported for Caucasians.

Influence of non-MHC genes on lymphocyte response to Mycobacterium tuberculosis antigens & tuberculin reactive status in pulmonary tuberculosis.

BACKGROUND & OBJECTIVES: Major histocompatibility complex (MHC) genes are known to influence the immune functions. In the present study, the influence of non-MHC genes such as mannose binding protein (MBP), vitamin D receptor (VDR) and interleukin-1 receptor antagonist (IL-1RA) gene polymorphisms on lymphocyte response to Mycobacterium tuberculosis culture filtrate antigen (10 micrograms/ml) was studied in 44 patients with active pulmonary TB and the family contacts (35) and in 32 normal healthy subjects. The influence of these gene polymorphisms on tuberculin (1TU of PPD of M. tuberculosis) reactivity status in 146 pulmonary TB patients was also studied. METHODS: The MBP and VDR genes were amplified using polymerase chain reaction (PCR) and genotyping was carried out using sequence specific oligonucleotide probes by dot blot and IL-1RA by agarose gel electrophoresis. RESULTS: A significantly decreased lymphocyte response to M. tuberculosis antigen was seen in pulmonary TB patients positive for functional mutant homozygotes of MBP (OO) compared to heterozygote carriers (AO; P < 0.02) and wild homozygotes (AA; P < 0.01). The variant mutant genotype (tt) of VDR gene was associated with an increased lymphocyte response in control subjects compared to active TB patients with tt genotype (P < 0.05). Heterozygote carriers of MBP (AO) were associated with a significantly (P < 0.001) decreased tuberculin reactivity compared to wild homozygotes (AA). The VDR genotype Tt (heterozygote carrier) was associated with an increased tuberculin reactivity in female TB patients as compared to male patients (P < 0.001). INTERPRETATION & CONCLUSIONS: The present study suggested that MBP and VDR genes influence the cell mediated immune response in pulmonary TB patients. Non-MHC genes along with HLA-Class II genes/gene products may be playing an immunoregulatory role in the mechanism of susceptibility/resistance to tuberculosis.

Association of vitamin D receptor genotypes with the susceptibility to pulmonary tuberculosis in female patients & resistance in female contacts.

To find out whether non-HLA genes such as vitamin D receptor (VDR) and Interleukin-1 receptor antagonist (IL-1RA) are associated with the susceptibility or resistance to pulmonary tuberculosis (PTB), genotyping of VDR, and IL-1RA genes was carried out in PTB patients (n = 202) and control subjects (n = 109). No marked difference in the frequency of the variant VDR genotypes was seen between the PTB patients as a whole and control subjects. However, a significant (P < 0.02) increase of VDR genotype tt (mutant homozygotes) was seen in the female PTB patients when compared to female contacts (spouses of male patients). Similarly, a significant (P < 0.02) increase of TT genotype (wild type homozygotes) was observed in female contacts compared to female patients. An opposite picture of the VDR genotype frequencies was seen in male patients and male contacts (spouses of female patients). Moreover, an increased frequency of tt genotype was observed in quiescent male patients compared to male relapse patients while no such difference was observed in female quiescent and relapse patients. These differences were not significant. No difference in the genotype frequencies of IL-1RA genes was seen between PTB patients and control subjects. The present study suggested that the genotype tt of vitamin D receptor gene may be associated with susceptibility to pulmonary TB in female patients, and the genotype TT may be associated with resistance in female contacts.

Lymphocytotoxic antibodies & immunity in pulmonary tuberculosis.

To understand whether the presence of cold reactive lymphocytotoxic antibodies (LCA) (reactive at 15 degrees C) in the system has any effect on immunity to tuberculosis lymphocytotoxic antibodies to adherent cells (enriched-B cells) and non-adherent cells were studied in active-TB (n = 42) and inactive-TB (cured) patients (n = 49) and healthy controls (n = 32). The plasma samples of inactive-TB patients showed higher percentage of positivity for lymphocytotoxic antibodies (36.7%) than the active-TB patients (21.4%) and control subjects (18.8%). No significant difference on antibody and lymphocyte response against Mycobacterium tuberculosis culture filtrate antigens was observed between LCA positive and LCA negative active-TB patients and normal healthy controls. Further, determination of HLA-DR phenotype of the patients and control subjects showed that individuals positive for lymphocytotoxic antibodies were more among HLA-DR2 positive and DR7 positive active-TB patients and control subjects than non-DR2 and non-DR7 subjects. The present study suggests that the cold reactive lymphocytotoxic antibodies may be against B-lymphocytes and persistent for a longer time. HLA-DR2 and -DR7 may be associated with the occurrence of LCA activity. Further, the presence of LCA has no immunoregulatory role on immunity to tuberculosis.

Influence of HLA-DR antigens on lymphocyte response to Mycobacterium tuberculosis culture filtrate antigens and mitogens in pulmonary tuberculosis.

SETTING: Influence of HLA-DR antigens and lymphocyte responses in pulmonary TB patients. OBJECTIVE: To elucidate the role of HLA-DR genes/gene products on lymphocyte responses to Mycobacterium tuberculosis antigens and mitogens, the present study was carried out in pulmonary tuberculosis during active and cured stage of the disease. DESIGN: Serological determination of HLA-DR antigens was carried out in 50 active TB patients, 44 cured TB patients and 58 normal healthy control subjects. The influence of HLA-DR antigens on peripheral blood lymphocyte responses to M. tuberculosis culture filtrate antigens and mitogens such as phytohaemagglutinin (PHA) and concanavalin-A (Con-A) was studied in the patients as well as normal healthy control subjects. RESULTS: Of all the DR antigens studied, patients (active TB and cured TB) with DR2 antigen showed an increased lymphocyte response (stimulation index) to a higher dose of antigenic (10 micrograms/ml) stimulation. A significantly lower lymphocyte response to antigen and mitogens was seen in HLA-DR3 positive normal healthy subjects than non-DR3 (DR3 negative) subjects. CONCLUSION: The present study suggests that HLA-DR genes/gene products may be playing an immunoregulatory role in eliciting an immune response against M. tuberculosis antigens and mitogens induced lymphocyte response in pulmonary TB patients and normal healthy subjects.

Association of functional mutant homozygotes of the mannose binding protein gene with susceptibility to pulmonary tuberculosis in India.

SETTING: Mannose binding protein gene polymorphism in pulmonary tuberculosis in India. OBJECTIVE: To find out whether non-HLA genes such as mannose binding protein (MBP) genes are associated in the susceptibility to pulmonary tuberculosis. DESIGN: Genotyping of MBP 52, 54 and 57 wild and mutant alleles was carried out in HLA-DR typed pulmonary tuberculosis patients (n = 202) and control subjects (n = 109). Since HLA-DR2 is associated with pulmonary-TB, the interaction of MBP genes on -DR2 and non-DR2 genes on the susceptibility was also studied. RESULTS: A significantly increased genotype frequency of MBP functional mutant homozygotes (including 52, 54 and 57) was seen in pulmonary tuberculosis (PTB) patients (10.9%) than in control subjects (1.8%; P = 0.008; odds ratio: 6.5). Analysis of interaction of MBP genes and HLA-DR2 on the susceptibility to PTB revealed that these genes are associated with PTB independent of each other. CONCLUSION: The present study shows that functional mutants of MBP are associated with PTB. Apart from HLA-DR2 association, association of non-HLA genes in the susceptibility to PTB is evident. This suggests that multigenetic factors (candidate genes) may be involved in the susceptibility/resistance to PTB.

Influence of HLA-DR2 phenotype on humoral immunity & lymphocyte response to Mycobacterium tuberculosis culture filtrate antigens in pulmonary tuberculosis.

Association of HLA-DR2 genes/gene products has been shown with pulmonary tuberculosis (PTB) patients in India. In the present study, the influence of HLA-DR2 and non-DR2 genes/gene products on immunity to tuberculosis has been studied. Plasma samples of -DR2 positive patients (active and inactive TB) showed a higher antibody titre to Mycobacterium tuberculosis culture filtrate antigens than non-DR2 (-DR2 negative) patients. Immunoblot analysis revealed a trend towards an increased percentage of DR2 positive patients recognizing 38, 32/34 and 30/31 kDa antigens of M. tuberculosis than DR2 negative patients. A low spontaneous lymphoproliferative response (without antigen stimulation) was seen in HLA-DR2 positive active TB patients than HLA-DR2 negative patients. However, the antigen stimulated lymphocyte response was higher in the -DR2 positive patients (active and inactive TB) when compared to non-DR2 patients. Further, an inversional correlation between antibody titre and spontaneous as well as antigen induced lymphocyte response (measured by 3H thymidine uptake and expressed as counts per minute) was seen in HLA-DR2 positive active PTB patients than non-DR2 patients. The present study suggests that HLA-DR2 genes/gene products may be associated with a regulatory role in the mechanism of disease susceptibility to tuberculosis. The genes while augmenting the humoral immune response, they suppress the spontaneous and antigen induced lymphocyte response in -DR2 positive patients with active disease.

HLA antigen profile in pulmonary tuberculosis patients & their spouses.

HLA-A, -B, -DR and -DQ antigen profile was studied in pulmonary tuberculosis patients (n = 209) and their spouses (family contacts; n = 50) and healthy volunteers (n = 72). An increased frequency of HLA-A-10, B7, B15, DR2 and DQ1 was seen in the pulmonary-TB (PTB) patients when compared to the total control subjects (n = 122). However, a significant increase was seen only with HLA-DR2 (P < 0.001; Pc < 0.01; Relative Risk 2.3) and -DQ1 (P < 0.005; Pc < 0.015; Relative Risk 2.8). Among the spouses and the corresponding patients, a similar increase of HLA-DR2 was seen. A decreased frequency of HLA-A19, B8, B17, B35, DR5 and DR6 were seen in PTB as compared to control groups. The present study suggested that HLA-DR2 and DQ1 genes/gene products may be associated with the susceptibility to tuberculosis either alone or in combination with other HLA or non-HLA genes.

HLA-DR2 phenotype and plasma lysozyme, beta-glucuronidase and acid phosphatase levels in pulmonary tuberculosis.

SETTING: Tuberculosis Research Centre, Indian Council of Medical Research, Madras, India. OBJECTIVE: To elucidate the role of HLA-Class II genes/gene products on phagocyte enzymes such as lysozyme, beta-glucuronidase and acid phosphatase in the plasma of pulmonary tuberculosis patients. DESIGN: Serological determination of HLA-DR and -DQ antigens was carried out in 54 active and 84 inactive pulmonary tuberculosis (quiescent) patients and 36 healthy control subjects. The levels of lysozyme, beta-glucuronidase and acid phosphatase were measured in the plasma of tuberculosis patients and control subjects. RESULTS: Increased lysozyme levels were observed in active pulmonary tuberculosis patients. beta-glucuronidase activity was higher in inactive-TB than in active-TB patients and control subjects. HLA-DR2 positive patients showed a lower lysozyme level than -DR2 negative patients. CONCLUSION: Increase in the plasma lysozyme level in active TB reveals the active stage of the disease. Further, increase in the activity of beta-glucuronidase in inactive-TB patients reveals the quiescent stage of the disease. The low level of lysozyme in HLA-DR2 positive patients may also be one of the possible factors involved in susceptibility to tuberculosis.

Influence of HLA-DR and -DO phenotypes on tuberculin reactive status in pulmonary tuberculosis patients.

SETTING: HLA and tuberculin status in pulmonary tuberculosis patients. Tuberculosis Research Centre, Indian Council of Medical Research, Madras, India. OBJECTIVE: To elucidate the role of HLA-class-II genes/gene products on tuberculin reactivity in pulmonary tuberculosis patients. DESIGN: Serological determination of HLA-DR and -DQ antigens was carried out in 62 healthy control subjects and 146 pulmonary tuberculosis patients. The tuberculin reaction pattern of pulmonary tuberculosis patients to PPD was studied and the role of HLA-DR and -DQ antigens (class-II gene products) on tuberculin reaction was analysed. RESULTS: HLA-DR and -DQ antigens did not influence high, medium and low tuberculin reaction dramatically in active pulmonary tuberculosis patients. However, a heterozygous combination of various HLA-DR antigens influenced the tuberculin reaction. CONCLUSION: The HLA-genetic make up (heterozygous combination) of the individual may influence the tuberculin reaction pattern in pulmonary tuberculosis.

Pulmonary eosinophilia in pulmonary tuberculosis.

Three radiologically and bacteriologically confirmed pulmonary tuberculosis patients had eosinophilic pneumonia, as demonstrated by BAL. In two patients, pulmonary eosinophilia was present only at the site of the lesion and the third had eosinophilia in both peripheral blood and lung. There was complete elimination of the eosinophilic inflammatory process in two patients who had successfully completed antituberculosis treatment.

Persisting alveolitis in miliary tuberculosis despite treatment with short-course chemotherapy.

Bronchoalveolar lavages in two patients with miliary tuberculosis have shown lymphocytic alveolitis. A 6-month regimen with an initial intensive 2-month phase resulted in remarkable clinical and radiographic improvement in both. However, bronchoalveolar lavage following treatment has shown that there was a persistence of lymphocytic alveolitis, though with reduced intensity. The significance of the persisting alveolitis, despite treatment, is not known at present. There is also a suggestion that compartment-alisation of lymphocytes may occur in miliary tuberculosis of the lung.

Long-term status of children treated for tuberculous meningitis in south India.

This report gives the findings of long-term follow-up (4 1/2-8 years) of 119 children who recovered from tuberculous meningitis. Of these, 17 patients died (10 due to severe tuberculous meningitis sequelae and 7 due to non-tuberculous causes) and 2 could not be traced. Of the remaining 100 patients for whom information was available, 47 (47%) made a complete recovery, while 53 (53%) had neurological sequelae--2 (2%) had severe, 39 (39%) moderate and 12 (12%) mild sequelae. There were no relapses during the 4 1/2-8 year period, indicating that regular treatment for 12 months may be adequate.