Mycobacterium kansasii, a nontuberculous mycobacterium, can cause pulmonary disease presenting clinical and radiological similarities to tuberculosis. M. kansasii infection has been associated with risk factors such as bronchiectasis, chronic obstructive pulmonary disease, tuberculosis sequelae, pneumoconiosis and immunosuppression. Herein, we describe a case of pleural effusion in a 67-year-old patient with chronic obstructive pulmonary disease and a history of pulmonary tuberculosis. The histological analysis demonstrated a granulomatous chronic process and acid-fast bacilli positivity, suggesting a diagnosis of pleural tuberculosis. M. kansasii was detected both in pleural fluid cultures and in cultures of tissue samples. We discuss the differential etiologic diagnosis with other infectious agents of granulomatous diseases, and we address treatment options.

Keywords: Mycobacterium kansasii; Mycobacterium infections; Pleural effusion; Case reports

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 ≥ 10 mm). Nevertheless, further studies are necessary so that indications, drugs, doses and duration of chemoprophylaxis regimens can be more properly defined.

Keywords: Silicosis; Tuberculosis; Diagnostic techniques and procedures; Chemoprevention.

Tuberculosis is a disease of high incidence and prevalence in Brazil. Imaging methods can reveal signs suggestive of tuberculosis activity or sequelae. Chest radiographs can reveal active lung tuberculosis through consolidations, cavitations, interstitial patterns (nodular and reticulo-nodular), mediastinal or hilar lymphadenopathy and pleural effusions. Images compatible with the active disease, such as centrilobular nodules segmentarily distributed, thick-walled cavities, thickened bronchial or bronchiolar walls, bronchiectasis and lymphadenopathy can be observed by computerized tomography. Thin-walled cavities, traction bronchiectasis, parenchymal bands, emphysema and mosaic pattern are signs suggestive of inactive disease. Gallium-67 citrate scyntigraphy is a complementary method useful in the detection of infectious diseases, including tuberculosis, especially in immunocompromised patients. Inhalation / perfusion analyses are used in the pre-operative assessment of patients carrying tuberculosis sequelaes and multiresistant tuberculosis. Positron emission tomography with fluorine-18 labeled deoxyglucose allows the detection of the inflammatory process that takes place during the active stage of tuberculosis and may persist, not so intense, after specific treatment is over. Imaging methods are valuable tools to be used in the diagnosis and follow up of pulmonary tuberculosis.

Keywords: Tuberculosis. Radiography. Computed tomography. Scintigraphy. Emission-computed tomography.

Objective: To analyze the epidemiological characteristics of and trends regarding the incidence of pleural TB. Methods: This was a retrospective descriptive study of TB cases reported between 1998 and 2005 and compiled from the Epidemiological Surveillance Tuberculosis System (Epi-TB database). Results: A total of 144,347 new cases of TB were reported during the period studied. Pulmonary TB was the predominant form (118,575 cases; 82.2%). Among the extrapulmonary forms (25,773 cases; 17.8%), pleural TB was the form most often reported (12,545 cases; 48.7%). For all forms, the incidence (per 100,000 population) decreased (from 49.7 in 1998 to 44.6 in 2005; R2 = 0.898; p < 0.001), whereas the incidence of pleural TB remained stable (4.1 in 1998 and 3.8 in 2005; R2 = 0.433; p = 0.076). The highest incidence of pleural TB was found among males (2:1) aged from 30 to 59 years. Of the 12,545 patients with pleural TB, 4,018 (32.0%) presented comorbidities: alcoholism (9.5%); HIV (8.0%); diabetes (3.3%); and mental illness (1.2%). The diagnosis was based on bacteriological (14.2%) and histological (30.2%) methods, as well as on unspecified methods (55.6%). Conclusions: Pleural TB was the predominant extrapulmonary form of TB in the state of São Paulo, with a stable incidence between 1998 and 2005, although there was a trend toward a decrease in the incidence of the pulmonary forms. The diagnosis of pleural TB was confirmed through histology and bacteriology in 44.4% of the cases.

Keywords: Pleural effusion; Tuberculosis, pleural; HIV.

Objectives: To evaluate clinical, laboratorial, epidemiological, and therapeutic aspects of patients presenting with multiresistant tuberculosis (MRTB). Patients and methods: From January 1993 to December 1994, a prospective, non-randomized study of patients presenting MRTB, characterized by failures under treatment schemes E-1 and E-3 according to the classification of the Brazilian Ministry of Health, and resistance to isoniazid and rifampicin was carried out. Clinical and laboratorial aspects were considered: age, gender, ethnical group, duration of condition, cavity occurrences in conventional X-rays, resistance to drugs by the indirect method according to Canetti's et al. proportional criteria; epidemiological aspects such as risk predictor factors for multiresistance and treatment results. This study consisted in two alternative chemotherapy courses combining an aminoglycoside, amikacin (Group A), or S, if sensitive (Group B), ofloxacin, clofazimine, in addition to other drugs, such as thiacetazone, ethambutol, or pyrazinamide, according to the sensitivity or to the prior limited use for a minimum of twelve months. Patients with unilateral radiologic lesions, functional possibilities, and who have accepted the indication were submitted to surgery (Group C). Treatment was at the outpatient clinic, self-administered, or under indirect supervision, with hospital admission allowed for clinical reasons, for a limited time, or when surgery was indicated. Patients with prior alternative treatment, those infected with HIV, pregnant patients, and those with renal failure were excluded from the study. Evaluation extended to twelve months after completion of treatment. Results: 70 patients with mean age of 37 years, 42 male, 44 caucasian, and 26 non-caucasian (two orientals), average duration of the condition of four years, and bilateral cavitary lesions in 55 (78.6%). Resistance to two drugs in 28.6%, 51.4% to three drugs, and 20% to four drugs. The most frequent risk predictor factor for MRTB was abandonment (54.3%) followed by recurrence after cure with treatment scheme E1 and failure at retreatment (14.3%), intolerance to drugs (11.4%), contact with MRTB (8.6%). The risk predictor factor could not be determined in 11%, acquired multiresistance being considered in 80%, and primary multiresistance in only 8.6% of the patients. Cure was observed in 25 patients of Group A (n = 39), 11 patients of Group B (n = 24), and 3 of Group C (n = 7). Only two discontinued treatment (A) and only two died during treatment (C). In the control period, three patients had recurrences (1 in A, and 2 in B), and 7 died (3 in A, 2 in B, and 2 in C). The effectiveness of Group A was 67.6% (25/37) at completion of treatment, and 64.9% during the post-treatment control. The effectiveness of Group B was 45.8% (11/24) at completion of treatment, and 37.5% during the post-treatment control. The effectiveness of Group C was 42.8% (3/7) at completion of treatment and during the post-treatment control. After twelve months, effectiveness at treatment completion in Group A fell from 64.1% to 61.5%, in Group B, it fell from 45.8% to 37.5%, and it remained unchanged in 42.8% in Group C, where the four cases of failure died. Drug discontinuation due to adverse effects occurred late in two cases, and other adverse effects were noted, but did not foster discontinuation of treatment.