Bronchial stenosis can impair regional lung ventilation by causing abnormal, asymmetric airflow limitation. Electrical impedance tomography (EIT) is an imaging technique that allows the assessment of regional lung ventilation and therefore complements the functional assessment of the lungs. We report the case of a patient with left unilateral bronchial stenosis and a history of tuberculosis, in whom regional lung ventilation was assessed by EIT. The EIT results were compared with those obtained by ventilation/perfusion radionuclide imaging. The patient was using nasal continuous positive airway pressure (CPAP) for the treatment of obstructive sleep apnea syndrome. Therefore, we studied the effects of postural changes and of the use of nasal CPAP. The EIT revealed heterogeneous distribution of regional lung ventilation, the ventilation being higher in the right lung, and this distribution was influenced by postural changes and CPAP use. The EIT assessment of regional lung ventilation produced results similar to those obtained with the radionuclide imaging technique and had the advantage of providing a dynamic evaluation without radiation exposure.

Keywords: Tomography; Electric impedance; Positive-pressure respiration; Pulmonary ventilation; Airway obstruction; Tuberculosis, pulmonary.

We report the case of a 50-year-old male with a rare combination: pulmonary tuberculosis and cutaneous leukocytoclastic vasculitis. The patient sought emergency treatment presenting with headache, arthralgia, cutaneous rash, and weight loss (4 kg) in the last 20 days. A chest X-ray, performed in a previous outpatient visit, revealed cavitation in the middle and upper lobes of the right lung, as confirmed by computed tomography. Sputum smear microscopy (Ziehl-Neelsen staining) was positive in three consecutive samples, and the result of the skin lesion biopsy was consistent with cutaneous leukocytoclastic vasculitis. The patient was therefore diagnosed with cutaneous leukocytoclastic vasculitis accompanied by pulmonary tuberculosis. Our objective was to describe a combination rarely reported in the medical literature and to discuss the possible pathogenic mechanisms of this combination.

Keywords: Vasculitis, hypersensitivity; Tuberculosis; Hypersensitivity.

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 determine the proportion of negative preoperative sputum smear results among patients presenting active TB, as identified through the evaluation of surgical samples. Methods: A retrospective study of patients undergoing surgery between 2003 and 2006 at a university hospital and receiving a histopathological diagnosis of active or latent TB. We reviewed patient histories, TB-related clinical aspects, acid-fast bacilli (AFB) test results, type of surgery performed and histopathological findings in surgical samples. Results: We included 43 patients, 27 of whom were male. The mean age was 44 ± 19 years. Twenty-eight patients had a history of TB (treated appropriately), and 15 reported no history of the disease. The main reason for seeking treatment was recurrent infection, followed by alterations seen in imaging studies. Of the 43 patients, 35 underwent preoperative AFB testing: 32 tested negative, and 3 tested positive. Among those 35 patients, the histopathological diagnosis was active TB in 26 and latent TB in 9. The 8 patients not submitted to preoperative AFB testing were also diagnosed with latent TB. The proportion of active TB in patients with negative sputum smear results was 72% (23/32), whereas that of negative sputum smear results in patients with active TB was 88% (23/26). Only 11.5% (3/26) of the patients had tested positive for AFB. Conclusions: Direct sputum smear microscopy has a very low yield. Many previously treated patients can present negative sputum smear results and yet have active TB. Active TB can be mistaken for secondary infections or for cancer.

Keywords: Tuberculosis; Diagnosis, differential; Sputum; Thoracic surgery; Thoracic surgery, video-assisted.

Objective: To describe data related to the pulmonary function of patients with sequelae of pulmonary tuberculosis, pleural tuberculosis or both. Methods: In the outpatient clinic of a university hospital, 218 patients were evaluated. Of those 218, 56 had sequelae of tuberculosis (pulmonary, pleural or both), and 162 had other types of tuberculosis. All patients were evaluated in the pulmonary function laboratory between February 2000 and July 2004, and 43 were found to be eligible for inclusion in the study. Patients with a history of asthma, chronic pulmonary obstructive disease, cardiac insufficiency, collagen diseases, silicosis or thoracic surgery, as well as those for whom spirometry yielded unacceptable results or was not performed, were excluded. The lung fields were divided into six zones, and radiographic results were classified by degree: I (involvement of only one zone with no cavitation); II (involvement of two or three zones or of one zone with cavitation); or III (extensive involvement of three or more zones with or without cavitation). Results: The final study sample comprised 50 patients, 44 (88%) of whom had pulmonary tuberculosis. The most prevalent form (17/50; 34%) was mixed ventilatory disturbance. Severe disturbances were more significant in degree III radiographs (p = 0.0002) and normal pulmonary function was predominant among patients presenting degree I and II radiographs (p = 0.002). Conclusion: The early discovery and treatment of tuberculosis contribute to reduce the number of cases, as well as the incidence of tuberculosis sequelae, thereby improving the quality of life of tuberculosis patients. Further studies, involving longitudinal, sequential analysis and larger samples of patients with tuberculosis sequelae, should be conducted in referral centers in Brazil.

Keywords: Tuberculosis, pulmonary/diagnosis; Tuberculosis, pleural/diagnosis; Respiratory function tests; Spirometry;

Tuberculosis and cryptococcosis are infectious diseases that can result in the formation of single or multiple nodules in immunocompetent patients. Exposure to silica is known to raise the risk of infection with Mycobacterium tuberculosis. We report the case of an elderly man with no history of opportunistic infections and no clinical evidence of immunodeficiency but with a six-month history of dry cough and nocturnal wheezing. A chest X-ray revealed a mass measuring 5.0 × 3.5 cm in the right upper lobe. The diagnostic approach of the mass revealed tuberculosis. The histopathological analysis of the surrounding parenchyma reveled silicosis and cryptococcosis. Cryptococcosis was also found in masses identified in the mediastinal lymph nodes. The surgical approach was indicated because of the degree of pleuropulmonary involvement, the inconclusive results obtained with the invasive and noninvasive methods applied, and the possibility of malignancy. This case illustrates the difficulty inherent to the assessment of infectious or inflammatory pulmonary pseudotumors, the differential diagnosis of which occasionally requires a radical surgical approach. Despite the presence of respiratory symptoms for six months, the first chest X-ray was performed only at the end of that period. We discuss the possible pathogenic mechanisms that might have led to the combination of three types of granulomatous lesions in the same lobe, and we emphasize the need for greater awareness of atypical presentations of pulmonary tuberculosis.

Objective: To compare clinical, radiological, and laboratory characteristics of individuals with pulmonary tuberculosis co-infected or not with HIV. Methods: A cross-sectional study, in which signs and symptoms were assessed by anamnesis and physical examination in patients hospitalized with pulmonary tuberculosis. The results of sputum smear microscopy and culture for Mycobacterium tuberculosis, as well as hemoglobin levels and CD4+ T-cell counts, were obtained from medical records, and chest X-ray reports were consulted. Results: We included 50 pulmonary tuberculosis patients, who were divided into two groups (HIV-positive and HIV-negative; n = 25 per group). The mean age of the participants was 38.4 ± 10.5 years; 46 (92%) were males; and 27 (54%) were White. Expectoration was presented by 21 (84%) and 13 (52%) of the patients in the HIV-negative and HIV-positive groups, respectively (p = 0.016). Radiological findings of cavitation were present in 10 (43%) and 2 (10%) of the patients in the HIV-negative and HIV-positive groups, respectively (p = 0.016), whereas an interstitial pattern was observed in 18 (78%) and 8 (40%), respectively (p = 0.012). The mean hemoglobin level was 11.1 ± 2.9 g/dL and 9.3 ± 2.2 g/dL in the HIV-negative and HIV-positive groups, respectively (p = 0.015). Conclusions: In our sample of tuberculosis patients, expectoration was less prevalent, hemoglobin levels were lower, and cavitation was less common, as was an interstitial pattern, among those co-infected with HIV than among those without HIV co-infection.

Keywords: HIV; Tuberculosis; Acquired immunodeficiency syndrome.

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.