rifampin and Silicotuberculosis

Silicosis, the most prevalent of the pneumoconioses, is caused by inhalation of crystalline silica particles. Silica-exposed workers, with or without silicosis, are at increased risk for tuberculosis and nontuberculous mycobacteria-related diseases. The risk of a patient with silicosis developing tuberculosis is higher (2.8 to 39 times higher, depending on the severity of the silicosis) than that found for healthy controls. Various regimens for tuberculosis chemoprophylaxis in patients with silicosis have been studied, all of which present similar efficacy and overall risk reduction to about one half of that obtained with placebo. Long-term regimens have potential side effects (particularly hepatotoxicity). In addition, the use of such regimens can jeopardize adherence to treatment. The current guidelines recommend that tuberculin skin tests be performed, and, if positive, that chemoprophylaxis be instituted. There are several possible regimens, varying in terms of the drugs prescribed, as well as in terms of treatment duration. We recommend the use of isoniazid at 300 mg/day (or 10 mg/kg/day) for six months for patients with silicosis, as well as for healthy patients with periods of exposure to silica longer than 10 years and strongly positive tuberculin skin test results (induration > or = 10 mm). Nevertheless, further studies are necessary so that indications, drugs, doses and duration of chemoprophylaxis regimens can be more properly defined.

Topics: Antibiotics, Antitubercular; Brazil; Humans; Isoniazid; Occupational Exposure; Pyrazinamide; Rifampin; Silicon Dioxide; Silicosis; Silicotuberculosis; Tuberculosis, Pulmonary

A medical facility for approximately 90,000 gold miners employed on 24 South African gold mines.. To evaluate the effectiveness of rifampicin, isoniazid and pyrazinamide given for 3 months for the prevention of tuberculosis in men with silicosis.. A randomised double-blind placebo controlled trial with active 4-year follow up of subjects by routine radiographic screening.. A total of 382 gold miners with silicosis were randomised to receive rifampicin 600 mg, isoniazid 400 mg and pyrazinamide 1.25 g daily as Rifater or a placebo. These men have been followed for 4 years since the end of the treatment period. Eleven men who received the combination tablet and 15 men who received the placebo tablet have developed tuberculosis (chi 2 df1 = 0.66, P = 0.4).. This multi-drug short course chemoprophylaxis regimen has failed to prevent tuberculosis in miners with silicosis. Even if a larger study had demonstrated a statistically significant effect of the regimen as compared with placebo, the rate of tuberculosis in the men who received the three-drug regimen was unacceptably high.

Topics: Adult; Antitubercular Agents; Double-Blind Method; Drug Administration Schedule; Drug Combinations; Follow-Up Studies; Gold; Humans; Isoniazid; Male; Middle Aged; Mining; Pyrazinamide; Rifampin; Silicotuberculosis

A 76-year-old woman was admitted to the hospital four times from November 2007 to June 2009. In this complex case, the patient had silicosis complicated by broncholithiasis, oesophagobronchial fistulas, and relapsed tuberculosis. She had worked as a stone crusher for 3 years and was exposed to a large amount of quartz dust. Barium oesophagography, gastroesophageal endoscopy, and biopsy suggested oesophageal-related chronic inflammation and ulceration, which may have caused the repeated oesophagobronchial fistulas. Bronchoscopy revealed a free broncholithiasis in the left mainstem bronchus. The patient was admitted a fourth time because of silicotuberculosis relapse. After 9 months of antituberculosis treatment, the patient recovered and was still clinically well at the time of this writing.

Topics: Aged; Antibiotics, Antitubercular; Bronchial Fistula; Esophageal Fistula; Esophagoscopy; Female; Humans; Isoniazid; Lithiasis; Pyrazinamide; Rifampin; Silicotuberculosis; Stents; Treatment Outcome

To evaluate the short and long-term effects of regimens containing INH, RFP with varied chemotherapy courses on culture-positive pneumoconio-tuberculosis.. 79 patients with culture-positive pneumoconio-tuberculosis were divided into three groups according to chemotherapy duration: 9-months group (M9: 2SHRZ/7HRE) 28 cases, 12-month group (2SHRZ/10HRE) 25 cases, 18-month group (M18: 2SHRZ/10HRE/6HR) 26 cases. Evaluating the efficacy of regimens depended predominantly on sputum bacteriological conversion, and the patients who completed the regimens were followed up for 5-8 years.. Sputum negative conversion rates of three groups at the end of chemotherapy were 83%, 96%, 95%, and their recurrent rates in follow-up period 41%, 4% and 5% respectively. Of all patients who completed the regimens bacteriological relapse rates from the first to fourth year are 6%, 8%, 2%, 2% in the follow-up period. There was no bacteriological relapse from fifth to eighth year.. It is effective for SHRZ/HRE combination with 12-months course to retreated tubercle bacillus positive pneumoconio-tuberculosis, and it is appropriate for such patients to be followed up for 4-5 years.

Topics: Aged; Antitubercular Agents; Drug Therapy, Combination; Follow-Up Studies; Humans; Isoniazid; Male; Middle Aged; Pyrazinamide; Rifampin; Silicotuberculosis; Streptomycin

A medical facility for approximately 90,000 gold miners employed on 24 South African gold mines.. To establish the long-term risk attributable to silicosis of relapse from pulmonary tuberculosis treated with short-course chemotherapy.. A consecutive sample of gold miners with pulmonary tuberculosis allocated to receive rifampicin, isoniazid, pyrazinamide and streptomycin given on weekdays for 5 months. Radiographs were assessed at the time of diagnosis for the presence of silicosis. All of the men were followed for at least 5 years after completing their treatment, or until they left mine service or suffered a relapse of tuberculosis.. The sample included 549 men of whom 167 had silicosis. The incidence density for relapse in silicosis was 1.55 (95% CI 0.97, 2.48) times that for the men without silicosis. There was no difference in the pattern of relapse over time between the two groups: the mean period to relapse in the men with silicosis was 2.6 years (SD 1.89 years) and for the men without silicosis was 3.1 years (SD 2.23 years) (P = 0.6).. Silicosis causes a small increase in the risk of relapse of tuberculosis. Relapses in both groups were not confined to the first 2 years after completion of treatment.

Topics: Adult; Antitubercular Agents; Drug Therapy, Combination; Follow-Up Studies; Humans; Isoniazid; Male; Pyrazinamide; Recurrence; Rifampin; Silicotuberculosis; Streptomycin; Tuberculosis, Pulmonary

Topics: Adult; Aged; Humans; Isoniazid; Male; Middle Aged; Mycobacterium tuberculosis; Rifampin; Silicotuberculosis

Topics: Aged; Aminosalicylic Acids; Antitubercular Agents; Arthritis, Rheumatoid; Bronchitis; Diabetes Complications; Drug Therapy, Combination; England; Female; Humans; Male; Mass Chest X-Ray; Mycobacterium tuberculosis; Nose; Occupations; Pneumoconiosis; Pulmonary Emphysema; Rifampin; Silicotuberculosis; Sputum; Streptomycin; Tuberculosis, Miliary; Tuberculosis, Pulmonary

Topics: Adult; Aged; Drug Combinations; Drug Resistance, Microbial; Ethambutol; Female; Humans; Male; Middle Aged; Rifampin; Silicotuberculosis; Time Factors; Tuberculosis, Pulmonary

Topics: Drug Combinations; Drug Resistance, Microbial; Ethambutol; Follow-Up Studies; Humans; Isoniazid; Rifampin; Silicotuberculosis; Sputum