Effect of additional oral ofloxacin administration in the treatment of multidrug-resistant tuberculosis.

The effect of additional oral ofloxacin administration was evaluated in 19 HIV-negative patients with multidrug-resistant tuberculosis (MDR-TB). Their mean duration of illness was 3.6 years. Based on chest roentgenograms, 13 patients had advanced disease and 6 had moderate disease. In addition to 'second-line drugs', patients were treated with oral ofloxacin; high dose 800 mg per day (12 patients), low dose 400 mg per day (2 patients) and intermittent twice a week regimen of 800 mg a day (5 patients). With treatment, there was a significant clinical improvement. Sputum smear conversion occurred in 18 patients (mean duration 15 weeks) and this sputum smear negativity persisted for a mean duration of 7 months. Chest roentgenograms revealed regression of lesions in 18 patients. Reversible side effects were encountered in four patients. Results of present study suggest that additional administration of oral ofloxacin is both effective and safe for the treatment of MDR-TB.

Studies on HBsAg binding with polymerised human serum albumin by ELISA.

A simple and sensitive ELISA was developed to characterize the interaction between polymerised human serum albumin (pHSA) and HBsAg, using pHSA-coated polyvinylmicrotitre plates as solid phase and anti-HBs-coupled HRPO as the conjugate. The interaction was found to be specific and dependent on the size of albumin polymer. pHSA-binding activity (pHSA-BA) was studied in both HBsAg-negative and HBsAg-positive sera from various liver diseases including acute viral hepatitis, fulminant hepatitis, cirrhosis of liver, chronic active hepatitis, and healthy HBsAg carriers. pHSA-BA was detected only in HBsAg-positive sera. Analysis of HBsAg-positive sera indicated pHSA-BA in high proportions of patients sera as compared to sera from healthy HBsAg carriers. pHSA-BA was detected both in the presence and absence of HBe markers, though the mean BA was relatively high in presence of HBeAg. The effect of human serum immunoglobulins (IgG, IgA, and IgM) on the BA was investigated and a correlation between pHSA-BA and HBsAg-IgM complex positivity in sera was established. Finally, the probable role of human serum IgM in facilitating the binding process was discussed.

Entamoeba histolytica: elevated nitroblue tetrazolium reduction activity in polymorphs during amoebic liver abscess.

Peripheral blood polymorphonuclear leucocytes (PMN) from patients with invasive amoebiasis, i.e. amoebic liver abscess (ALA) and acute amoebic dysentery, showed marked elevation of nitroblue tetrazolium dye (NBT) reduction. This dramatic change was not observed in PMN from patients with non-invasive amoebiasis, i.e. non-suppurative hepatic amoebiasis, or in asymptomatic Entamoeba histolytica cyst passers. A small number (12%) of patients with viral hepatitis displayed increased NBT reduction. 10 to 12 days after recovery following treatment, the majority (75%) of ALA patients failed to show increased NBT reduction. Our results suggest that the PMN-NBT reduction test could be useful as an aid to the diagnosis of ALA.

Enzyme linked protein-A: an ELISA for detection of amoebic antibody.

Enzyme linked protein-A was used to develop an enzyme linked immunosorbent assay (ELISA) system for the detection of circulating antibodies to amoebic antigen. The specificity of protein-A to bind IgG only through Fc receptors, makes the test more specific for the detection of IgG antibodies to amoebic antigen. The ELISA system was used to detect amoebic antibody in control subjects (56), patients with amoebic liver abscess (79) and Entamoeba histolytica cyst-passers (10) and the results compared with those of indirect haemagglutination assay (IHA). The ELISA was more sensitive and detected 74.7% of cases with amoebic antibody in amoebic liver abscess compared with 66.7% detected by IHA. The test was more specific, sensitive and easy to perform and is recommended as a test of choice for the serological diagnosis of amoebic liver abscess.

Enzyme linked protein-A: an ELISA for detection of IgG antibodies against Mycobacterium tuberculosis in intestinal tuberculosis.

Enzyme linked protein-A has been used to develop an enzyme-linked immunosorbent assay (ELISA) to detect circulating IgG antibodies to Mycobacterium tuberculosis. The specific binding of protein-A to IgG fractions through Fc receptors, makes the test more specific for detection of total IgG antibodies. The ELISA system has been used for detection of circulating antibodies to M. tuberculosis H37Ra in 22 patients with histologically proven intestinal tuberculosis and 88 healthy controls, in addition to 7 diseased controls. The ELISA has been found to be a sensitive test as it was positive in all 22 patients with intestinal tuberculosis. Its specificity was 85% in Indian controls and 97% in Norwegian controls. The test is easy to perform and may be recommended for the serological diagnosis of intestinal tuberculosis.

Serodiagnosis of intestinal tuberculosis by the soluble antigen fluorescent antibody test (SAFA test).

The diagnosis of intestinal tuberculosis can only be established by the tissue obtained during surgery or endoscopy. We investigated the role of the soluble antigen fluorescent antibody (SAFA) test with the possibility that it may prove to be a valuable technique for the serodiagnosis of intestinal tuberculosis. The sera of 38 patients and 60 control subjects were studied. Mycobacterial saline extract was used as an antigen in the test. Thirty-two (84%) of 38 patients with intestinal tuberculosis yielded positive values (fluorescence coefficient greater than 3). Among the control subjects a false positive result was observed in only one patient who had eosinophilic enteritis. Patients with intestinal tuberculosis had a significantly higher level of antibodies than patients with non-tuberculous intestinal disease and healthy subjects. These results suggest that this technique may be used for the diagnosis of intestinal tuberculosis and in differentiating it from other non-tuberculous intestinal diseases.

Serodiagnosis of intestinal tuberculosis by enzyme immunoassay and soluble antigen fluorescent antibody tests using a saline extracted antigen.

The efficacy of enzyme-linked immunosorbent assay (ELISA) and soluble antigen fluorescent antibody (SAFA) tests in the diagnosis of intestinal tuberculosis was compared using saline extracted surface antigen of M. tuberculosis H37Ra. Of the 24 proved cases of intestinal tuberculosis ELISA detected positivity in 92% compared with 83% detected by the SAFA test. The 2 tests showed a strong correlation with each other and yielded a clear cut difference between patients and controls, although there was some degree of overlap.

Immunochemical characterization of saline-extracted antigens of Mycobacterium tuberculosis H37Ra.

The saline extract (SE) of Mycobacterium tuberculosis H37Ra yielded four major fractions on Sephadex G-100, with average molecular weights of 48,000 (fraction I, F I) 32,000 (fraction II, F II), 15,000 (fraction III, F III) and 5,000 (fraction IV, F IV). FI and FII gave single bands on sodium dodecyl sulfate-polyacrylamide gel electrophoresis, showed complete immunological cross-reactivity with each other and were more potent in reacting with antibodies in patients' (tuberculosis) sera than sonicate, SE, purified protein derivative, F III and F IV when tested in a competition enzyme-linked immunosorbent assay.

Intestinal tuberculosis: bacteriological study of tissue obtained by colonoscopy and during surgery.

The biopsy tissue obtained during surgery and colonoscopy from 28 cases of intestinal tuberculosis was utilized for isolation and identification of mycobacteria. The mycobacteria could be isolated in 12 (42%) of 28 patients. Colonoscopy can be a successful method of bacteriological diagnosis of intestinal tuberculosis. Mycobacteria were scarcely ever seen on histological sections. Combined use of guinea pig inoculation and culture was more rewarding than either alone. The yield of positive cultures was greater in tissue with caseation necrosis, though organisms were also recovered from tissues showing non-caseating granuloma and non-specific inflammation. The intestinal tissue gave more positive cultures (41%) than did lymph nodes (14%). The organisms were isolated in patients with or without pulmonary lesions and chemotherapy in the past. All the organisms were isolated as Mycobacterium tuberculosis.

Diagnosis of ileocecal and colonic tuberculosis by colonoscopy.

The colonoscopic findings in 11 proven cases of ileocecal tuberculosis consisted of deformed ileocecal valve in all 11 and contracted cecal lumen in 10. This was associated with mucosal nodules predominantly around the ileocecal valve, pseudopolypoid folds, and mucosal protuberance. Two patients had an isolated cecal ulcer. In three of the 11 patients the examination enabled a histologic diagnosis to be made on the basis of typical granuloma. In the other four patients Mycobacterium tuberculosis was isolated from the tissue obtained through biopsies.