Human immunodeficiency virus-related tuberculosis and primary drug resistance in Bangkok, Thailand.

SETTING: Central Chest Hospital, a 500-bed referral hospital near Bangkok with a large out-patient department. OBJECTIVES: To determine human immunodeficiency virus (HIV) seroprevalence among patients with pulmonary tuberculosis (TB), and compare HIV-positive and HIV-negative TB patients. DESIGN: From July 1995 through June 1996, a cross-sectional study was conducted of newly registered adults (> or =16 years old) with suspected pulmonary TB. RESULTS: Of 2587 newly registered patients with suspected pulmonary TB, 2019 (78%) received HIV pretest counseling and 1816 (90%) consented to testing. Of these, 364 (20%) were HIV-seropositive. Among 1091 patients with bacteriologically confirmed TB, HIV seroprevalence was 22%. HIV-positive patients were more likely to be young, unemployed, single men and to have a history of injection drug use. HIV-positive patients with first-episode TB were more likely to have Mycobacterium tuberculosis strains resistant to isoniazid (10.9% vs 3.5%; P < 0.001), rifampicin (9.4% vs 2.9%; P < 0.001), and at least isoniazid and rifampicin (multidrug-resistant TB [MDR-TB]; 5.2% vs 0.4%; P < 0.001). CONCLUSIONS: HIV prevalence is high among TB patients at this Bangkok hospital and is associated with drug resistance, including a 12 times higher risk of MDR-TB. These findings underscore the urgent need to assure adherence to complete, effective TB treatment regimens for all patients, including persons who are potentially difficult to manage such as injection drug users.

A comparison of two short course tuberculosis chemotherapy regimens, both using Rifater during an intensive phase, with a 3 year follow-up.

Tuberculosis is still a major public health threat in Thailand. The introduction of a short course of chemotherapy at national level might help reduce the magnitude of the problem. In order to assess the efficacy and toleration of two different regimens of chemotherapy under field conditions, a comparative clinically controlled trial was conducted at the Central Chest Hospital in Nonthaburi, Thailand. From January 1988 to August 1990, 199, newly diagnosed, untreated, sputum positive tuberculosis patients were allocated randomly to two treatment groups; in Group A, 97 patients received Rifater daily for the first 2 months, followed by Rifinah daily for 4 months (2 Rifater/4 Rifinah). In Group B, 102 patients received Rifater supplemented by ethambutol daily for the first 2 months followed by thiacetazone and isoniazid daily for 6 months (2 Rifater EMB/6 HT.) Treatment results were very satisfactory in both groups. At the end of treatment conversion rates were 100 per cent in Group A, and 99 per cent in Group B. After a period of 36 months following completion of treatment, relapse rates of 3 per cent for Group A and 4 per cent for Group B were observed. Adverse reactions were minimal in both groups, but acne formation and gastrointestinal symptoms were noticed more in Group B, suggestive of thiacetazone side effects. This study shows that, the 6-months regimen is as effective as the 8-months regimen. Although the 8-months regimen is cheaper, it causes more gastrointestinal disturbance and skin reaction which might led to less patient compliance and result in a lower cure rate.(ABSTRACT TRUNCATED AT 250 WORDS)

Value of an ELISA for mycobacterial antigen detection as a routine diagnostic test of pulmonary tuberculosis.

A double antibody sandwich ELISA was carried out with commercially available anti-BCG and peroxidase labeled anti-BCG, for the detection of mycobacterial antigens. By using purified protein derivative of tuberculin (PPD) as the antigen, the lowest detection limit of the assay was found to be 0.05 microgram/ml. At the cut off level of absorbance index (Al) greater than or equal to 5. positive results of ELISA were obtained from 24/25 sputum specimens which were positive for staining of acid fast bacilli (AFB), 5/16 specimens positive for culture of Mycobacterium tuberculosis and 67/69 specimens positive for both tests. The assay was positive in only 11/164 specimens negative for both staining of AFB and culture of M. tuberculosis. 4 of which were known to have tuberculosis. Thus, with sputum specimens, the sensitivity, specificity, efficiency, positive predictive value and negative predictive value of the ELISA were 87.27, 93.29, 90.88, 89.72 and 91.62 percent respectively. Positive results were also obtained in 2/111 sputum specimens which were positive for other bacteria but the presence of AFB in these specimens could not be ruled out. With pleural fluid specimens, positive ELISA with Al greater than 1 was found in 3/26 specimens of patients with tuberculous pleurisy and 0/11 of those with malignancy. Twenty-six sera and urine specimens of tuberculous patients and also all control specimens (138 sera and 86 urine specimens) assayed, gave negative ELISA results (Al less than 1).