Objectives: To describe a group of patients with thymoma who were submitted to surgica treatment associated or not with therapy, and evaluate their prognosis. Methods: Of the 104 patients with thymic tumors who were operated at Hospital das Clínicas - São Paulo University Medical School between 1965 and 1998, (66.3%) were males. Mean age at diagnosis, was 47.9% ± 16.3 years (ranging from 13 to 76 years). Results: Of the 104 patients, 89 (85.6%) underwent complete thymoma resection, 6 (5.8%) underwent partial resection and, in 9 (8.6%) of them, biopsy was performed. Anatomopathologic diagnosis (thymoma vs malignant thymoma) and the type of surgery (biopsy vs complete resection vs partial resection) were significant predictors of survival mean time (p < 0.02). Conclusions: Complete resection is the treatment of choice for thymomas. These tumors, when not invasive and completely resected, have good immediate and late prognosis.

Keywords: Thymoma.

Objectives: To report the results obtained in six-minute walk tests (6 MWT) performed in a group of patients under a pulmonary rehabilitation program (PRP) as a contribution to a better interpretation and the proper use of this test. Some factors that interfere with physical training during pulmonary rehabilitation were also studied. Methods: Retrospective data on 18 males and 5 females under a PRP were evaluated. During 3 months, the patients had 3 weekly training sessions to exercise the muscles of the lower extremities. The following parameters were analyzed before and after training: the distance walked during the 6 MWT and its relationship with the reference values calculated by the equations of Enright and Sherril; forced expiratory volume in one second, training load, heart rate (HR), respiratory rate (RR), oxygen saturation by pulse oxymeter (SpO2) and body mass index (BMI). Results: The values obtained during pre-training 6 MWT did not differ from the reference values calculated by Enright and Sherril equations (P = 0.777). After training, these values differed significantly (P = 0.001). The mean 6 MWT distance increase was 76 m. However, 3 patients did not reach the minimally significant increase of 54 m. Post-training 6 MWT correlated positively with pre-training FEV1 (P = 0.012), but not with load increase during training (P = 0.693). No significant difference in RR and SpO2 was observed before and after training. HR increased significantly at the end of post-training 6 MWT (P = 0.035). In 9 patients BMI was lower than the inferior limit. Six of them (66%) presented post-training distance increased in 54 m or more. Conclusions: The use of standardized methods for 6 MWT performance is recommended, even when reference values are targeted. The equations of Enright and Sherril for healthy subjects tended to yield underestimated values, with no statistical differences in training values in COPD patients. Differences in the encouragement technique employed could explain these conflicting results. Physical gain after rehabilitation was confirmed regardless of the patient's initial functional status, justifying the indication of rehabilitation even to those with severe respiratory limitations. The heterogeneous responses to load increase suggest the analysis of the predictive factors of the best response to training is necessary to customize load increase and thus obtain the best performance possible.

Keywords: Exercise test. Obstructive lung diseases. Rehabilitation. Respiratory function tests. Exercise.

Objective: To evaluate the effects of non-invasive positive pressure ventilation (NIPPV) on acute respiratory failure and to identify the factors associated with its failure or success. Patients and methods: This open and prospective study analyzed 60 episodes of NIPPV use in 53 patients with respiratory failure. Results: In 37 occasions (62%), the patients were successfully ventilated with NIPPV (Success Group, SG) whereas in 23 episodes (38%) intubation was necessary (Failure Group, FG). FG patients showed a higher Apache II score (30.4 ± 9 versus 22.2 ± 8, p = 0.001). The use of NIPPV reduced respiratory rate after 2 hs. This reduction was less evident in FG (from 33 ± 9 to 30 ± 8 bpm, p = 0.094) than in SG (from 39 ± 11 to 28 ± 9 bpm, p < 0.001). PaO2 increased from 62 ± 22 to 101 ± 65 mmHg, (p < 0.001) with no differences between groups. Among patients with hypercapnia, PaCO2 level decreased in SG (from 76 ± 20 to 68 ± 21mmHg, p = 0.032) but not in FG (from 89 ± 23 to 93 ± 40mmHg, p = 0.54). Arterial pH increased in SG (from 7.25 ± 0.10 to 7.34 ± 0.11, p = 0.007) and not in FG (from 7.24 ± 0.07 to 7.21 ± 0.12, p = 0.48). NIPPV was used for longer in SG (3.4 ± 2.5 versus 2.3 ± 2 days, p = 0.003). Higher IPAP levels were used in SG (13.2 ± 3 versus 11 ± 4cmH2O, p = 0.02). The 10 patients (17%) who died, all belonged to FG. Skin lesions at the site of mask contact was the most common complication of NIPPV (5, 8%). NIPPV was efficient in treating acute respiratory failure in 2/3 of patients. The factors associated with failure were: greater severity of the illness, smaller reduction in the respiratory rate, no improvement of respiratory acidosis in 2 h and use of lower IPAP levels. The high mortality rate observed in FG (10, 43%) justifies efforts to optimize NIPPV implementation and to recognize its failure, as early as possible, in order to avoid delays in endotracheal intubation.

Keywords: Non-invasive positive pressure ventilation. Respiratory failure. Apache II. Hypercapnia.

Multidrug-resistant tuberculosis (MDR-TB) is a worldwide concern but its magnitude in the state of Ceará - Northeastern Brazil has been so far unknown. Objectives: To determine the prevalence of MDR-TB among us as well as the sesceptibility of Mycobacterium tuberculosis to antituberculosis drugs. Methods: A retrospective study was conducted using 1,500 susceptibility tests (ST) for rifampin (RFM), isoniazid (INH), streptomycin (SM), pyrazinamide (PYZ), ethambutol (ETM) and ethionamide (ETH) that were performed at the Central Laboratory of the State of Ceará (LACEN) between 1990 and 1999. The proportion method test was used. Results: Of the 1,500 stains studied, 404 (27%) were resistant to at least one drug, including both primary and acquired resistance. MDR-TB, defined as resistance to at least rifampin and isoniazid was observed in 266 (17.7%) patients. During the study period, there were 41,073 TB cases and MDR-TB prevalence was 0.65% in our state. Among the patients studied, 62.3% were men and mean age was 40.17 ± 14.62. Overall prevalence for single-drug resistance was 8.1% (INH = 5.7%; SM = 1.5%; and RFP = 0.9%). Resistance to 2, 3, 4, 5 and 6 drugs was, respectively, 10.8%; 3.1%; 0.9%; 1.5%; and 2.9%. HIV testing was performed in all inpatients and some outpatients (total of 86 patients) and revealed that they were all HIV negative. The probability of 5-year survival (138 patients assessed) was greater in the MDR-TB group treated with alternative drugs, including the patients of the failure group. Conclusion: The MDR-TB prevalence rate found in this study is intermediate in comparison with those reported in Brazil and the other parts of the world. Preventive approaches, early diagnosis and the development of effective, safe and relatively inexpensive new drugs should be stimulated.

Keywords: Multidrug-resistant tuberculosis. Prevalence. Survival probability.

In its 1991revision, the American Thorax Society (ATS) recommended that each region should define its own equations to determine the theoretical, or predicted values of the spirometric parameters that best represent the pulmonary functional reality of the local population. At that time, the United States already had various equations of its own as well as the European Community, specially Poland. In 1992, Pereira et al., analysing 4,200 spirograms on healthy Brazilians, found predicted values (PV) of forced vital capacity (FVC), forced expiratory volume in 1 sec (FEV1) and middle expiratory flow (MEF) different from those reported by American and European authors. The purpose of the present study was to compare the equations developed by Pereira et al., using a Brazilian sample population, with those determined by Knudson et al. for American populations, that are the most used by Brazilian specialists. This study included 1,070 spirograms performed in patients of both genders (389 males and 681 females) who came to our service for routine functional assessment. No pathology was excluded and the smoking status of the patients was not taken into account. For each patient the PV of FVC, FEV1 and MEF were calculated accordingly to the equations of Pereira et al. (PV-P) and Knudsen et al. (PV-K). Subsequently, the means, standard deviations and reports obtained by both methods were compared. Among females, the PV-K of FVC were 4,01% (p < 0.005) greater, leading to a higher rate of restrictive impairment whereas among males there was no significant difference. Regarding FEV1, PV-P were higher in both males (4.76%; p < 0.005) and females (5.04%; p < 0.05) resulting in a greater sensitivity in the identification of respiratory obstructions. No significant difference was observed between PV-P and PV-K as to FEF25-75 regardless of gender.

Keywords: Spirometry. Reference values. Forced expiratory flow rates.

Biological markers are cellular, structural and biochemical components that can define cellular as well as molecular changes in both normal and neoplastic cells. There are two types of biological markers: 1) intermediate markers that evaluate cellular and molecular alterations before malignancy occurs; and 2) diagnostic markers, present in association with malignancy. The identification and validation of biological markers for clinical use are performed in stages: initial identification in cell cultures of the tumor;
testing of the marker in tissues obtained in biopsies of patients with an established diagnosis of the tumor;
testing of biopsies of normal tissues and tissues with an inflammatory process;
sputum, blood or urine tests for validation as a non-invasive test that can be used in high-risk populations. Sorologic and histopathologic biological markers are cellular, structural and biochemical components found in both normal and neoplastic cells that can be quantitatively assessed by biochemical, immunological and molecular methods in the body fluids or tissues, respectively, and may be associated with malignancies and, possibly, with the neoplastic organ. Biological markers are studied in diverse primary neoplasms. However, few of them proved to be clinically valuable. The role of biological markers in lung cancer patients remains unclear because only a small number of markers has been properly identifiassessed. The aim of this paper is to understand the role of sorologic and histologic biological markers in the prognosis and survival of lung cancer patients based on our previous works. Furthermore, we present a future perspective of the early detection of lung cancer on the basis of the role of intermediate biological markers.

Keywords: Biologic markers. Lung cancer. Prognosis. Survival. Morphometric method.

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.

Patients with severe asthma and blunted perception of their bronchial obstruction are likely to have elevated risk of death from asthma. The authors describe the case of a 52-year-old woman with asthma whose test results, in a prospective study for the identification of patients with blunted perception of the intensity of their own bronchial obstruction, showed the minimum score in the analogic visual scale in the presence of reduced morning FEV1 and EFP. After the study, the patient was seen at the outpatient clinic. He had no complaints, seemed normal at physical examination and reported to be using no medication at all. Then, while still in the clinic, he suddenly developed dyspnea, respiratory failure, and non-revertible cardio-respiratory failure. Blunted perception of the bronchial obstruction severity probably contributed to the development of acute respiratory failure and death of the patient.

Keywords: Dyspnea. Asthma. Bronchial spasm. Death. Perception.

We report on a 37-year-old female patient who was first seen on account of a progressive dyspnea of 18 month's duration. Admission diagnosis was bronchial asthma. Over the past seven years, the patient has had seven pneumonia episodes involving mainly the lingular segment. Seventeen years prior to admission (1982) she was orally intubated for 15 days due to meningococcus meningitis and coma. Fiberoptic bronchoscopy revealed marked widening of the carina and stenosis of the main bronchi, confirmed by virtual bronchoscopy. The stenosis was shorter and more severe to the right side (1 cm) and longer and less severe on the left side (2 cm). The patient was submitted to carina resection and anastomosis of the right mainstem bronchus to the trachea and the left main bronchus to the bronchus intermedius. Fifteen months after surgery the patient shows good clinical, radiological and functional evolution.

Keywords: Carinal stenosis. Mainstem bronchus stenosis. Carinal reconstruction.

Air cysts abnormally emerging from the trachea and/or larger bronchi is an extremely rare disease. Only a few isolated cases of paratracheal air cysts associated with chronic lung diseases have been described in the literature. The aim of this communication is to describe two cases of this rare, clinical entity in members of the same family. The father of the patients died from this disease at 43 years of age and his two daughters are currently under treatment. The clinical findings are similar to those of chronic pulmonary suppuration syndrome. The diagnosis was established by bronchovideoscopy, axial CT with 3D reconstitution and virtual bronchoscopy. The patients are under observation and palliative treatment is being administered.

Keywords: Lung diseases. Cysts. Trachea. Bronchi. Bronchoscopy. Computed tomography.