Cold reactive lymphocytotoxic antibodies in pulmonary tuberculosis: correlation with disease activity and HLA.

Cold reactive lymphocytotoxic antibodies (LCA) are more reactive in cold than at 37 degrees C and occur following infection, immunization or vaccination and in various autoimmune diseases. In the present study, LCA activity against T and B-lymphocytes has been investigated in patients with pulmonary tuberculosis (PTB), their various clinical sub-groups and consanguineous relatives. Further, the relevance of HLA factors in LCA activity was analyzed. The sera from 144 PTB patients, 52 family contacts and 52 healthy individuals were tested for presence of LCAs by a modified two-stage NIH microlymphocytotoxicity assay. A significant increase in LCA activity against both T (32.6% vs 5.7%, P < 0.0001) and B (59.7% vs 13.4%, P < 0.0000001) cells was observed in PTB patients as compared to healthy controls. There was no correlation between serum LCA activity and sputum acid-fast bacilli status. However, only B cell LCAs revealed significant increase in parallel to disease advancement as assessed by X-ray chest examination. Further, LCA activity was more pronounced in drug responders than drug failure group of patients. No significant difference in the distribution of HLA class I and class II antigens was observed between LCA positive and LCA negative patients. However, panel cells carrying HLA-A1, -A11 and -DR3 were often found reactive in LCA positive patient sera. In household family contacts, LCAs were significantly increased only against B cells as compared to healthy controls (38.4% vs 13.4%, P < 0.01). This study suggests that Mycobacterium tuberculosis infection/exposure could account for the occurrence of LCAs in pulmonary tuberculosis and the strength of these antibodies is related to disease severity and the extent of lung involvement.

Knowledge, attitudes and practices of newly diagnosed sputum positive cases of pulmonary tuberculosis.

Lack of awareness of risk posed to the community by a sputum positive case of Pulmonary Tuberculosis (PTB) is an impediment in the control of Tuberculosis. A study involving 212 newly diagnosed sputum positive patients aged 15 years or more, revealed that only 9% of the patients knew correctly the cause of PTB. Knowledge about mode of spread of the disease was not known to 49% of patients. Awareness regarding the investigations like chest X-ray and sputum examination was high as 70% but utility of sputum examination was known to only 29% of the patients. Awareness of harmful sequelae of inadequate and incomplete treatment was as high as 93% but knowledge per se of adequate duration of treatment was poor in a half (50%) of the subjects. Attitude towards domiciliary treatment was generally positive (88%) Practices regarding safe sputum disposal and preventive measures practised in the families were poor in nearly two third's of patients. Health education efforts need to be strengthened to create better awareness of these important aspects of tuberculosis diagnosis, treatment and control.

HLA class I profile in Asian Indian patients with pulmonary tuberculosis.

HLA class I antigen profile was studied in 153 unrelated patients with pulmonary tuberculosis (PTB), 40 family contacts and 289 healthy individuals by the NIH microlymphocytotoxicity test to find out the role of HLA-A, -B, -C alleles in influencing susceptibility to PTB and its various clinical groups. HLA-A2 was found to be significantly increased in the total patient group as compared to controls (38.6% vs 26.3%, p < 0.01, RR = 1.76). The increase of HLA-A2 was more pronounced in the sputum negative patients (59.4%, pc < 0.001, RR = 4.1) suggesting its possible role in the mediation of CD8+ suppressor T cell activity against Mycobacterium tuberculosis, resulting in the development of limited disease in these patients. Further, HLA-B18 was found to be decreased in patients as compared to controls (2.6% vs 7.3%, p < 0.05, RR = 0.34). None of the class I antigens was associated with the dynamics of chemotherapy or disease severity as assessed by the extent of lung involvement on chest X-ray examination.

Endemicity of cholera among rural areas of Loni, Ahmednagar district of Maharashtra.

A total of 130 Vibrio cholerae strains isolated during November 1989 to December 1992 from the rural population of Loni areas--Ahmednagar district of Maharashtra were characterised. Of these isolates, 124 were El tor vibrios serotype Ogawa, and 6 were El tor vibrios serotype Inaba. One hundred twenty two strains belonging to T4 phage, while 8 strains of El tor vibrio serotype Ogawa were untypable. All the strains isolated, showing haemolytic and non-haemolytic colony variants of El tor V. cholerae, and had resistance of one or more antibiotics. Maximum incidence was observed in November-December, the illness had a mild onset and no fatality was reported.

G-6PD deficiency in malaria endemic areas of Udaipur District in Rajasthan.

Nine thousand four hundred thirty three pyrexial cases were screened for the evidence of Malaria and Glucose-6-phosphate dehydrogenase deficiency among the rural tribal population of seven primary health centres in the malarial endemic areas of Udaipur District in Southern Rajasthan. One thousand four hundred five (P. Falciparum 831 and P. Vivax 574) cases were positive for malaria and 170 for G-6PD deficiency. Incidence of G-6PD deficiency in malaria, when compared to the non-malarial cases revealed statistically insignificant alterations (X2 is calculated to 0.1299 which for 1 degree of freedom gives P > 0.05).

Prevalence of hepatitis surface antigen among rural population of Loni area in Ahmednagar district of Western Maharashtra.

Three hundred and fifty three subjects among the rural population of Loni area admitted in the hospital, and 188 medical staff members working in the Rural Medical College and Hospital, Loni, were screened for the presence of HBsAg. Reveresed passive haemagglutination assay was used for screening; it showed an HBsAg positivity rate of 21.8% and 15.8% among hepatitis and non hepatitis cases respectively, and 1.2%, 0% and 4.2% among medical students, doctors and nursing staff respectively. A high HBsAg positivity rate has been observed in the rural population of Loni area.

Restriction endonuclease analysis of DNA in sickle cell lesions among tribals of Bihar, Madhya Pradesh, Gujarat & Rajasthan.

Restriction endonuclease analysis of DNA was undertaken in blood samples from individuals who were normal (110), had sickle cell trait (44) and homozygous sickle cell disease (6) from the tribal populations of Bihar, Madhya Pradesh, Gujarat and southern Rajasthan. DNA was prepared from all the blood samples and processed for restriction enzyme digestion, agarose electrophoresis, prehybridization, Nick-translation hybridization and autoradiography. A polymorphic HpaI restriction endonuclease recognition site on the 3' side of the beta-globin gene was used to analyse to determine the beta-globin gene mutant S. It was found that mutation has resulted within the normal 7.6 Kb HpaI fragment among the tribal populations studied. On comparing the results with those from Middle East and East Africa it appears that the sickle gene mutation in India, Saudi Arabia and Kenya arose separately from that in West Africa.