The aim of this study was to analyze the results of 17 patients with myasthenia gravis who, from 1985 to 1994, were submitted to thymectomy at the Medical School of Santa Casa de São Paulo. Nine patients (52.9%) were female and the mean age was approximately 30.3 years. The most usual symptoms were ptoses, weakness, and diplopia. Other symptoms included: dyspnea, dysphonia, thoracic pain and loss of weight. The average development period of the disease was 17.5 months (between 3 and 96 months). The diagnostic methods use were chest X-ray, response to edrophonium chloride (Tensilon), electrophysiologic study and thoracic CT. All patients were submitted to thymectomy through medium sternotomy. Patients were followed up from one month to ten years. Only one patient did not return to the clinic. Twelve patients (75%) achieved good results. The others four patients presented little or no response after thymectomy.

Keywords: Thymectomy. Myasthenia gravis.

Background: Extended thymectomy is one of several types of thymectomy. Literature suggests that the outcome and prognosis will be enhanced by performing a more extensive resection of the gland and of the anterior mediastinum tissue. Objective: To retrospectively evaluate response of MG patients to extended thymectomy. Method: From August 1992 to January 2003, forty-six MG patients were submitted to preoperative plasmapheresis and extended thymectomy. According to the time elapsed since onset of symptom they were divided into three groups; < 12 months, 13 to 24 months, and > 25 months. Results: There were 31 female and 15 male patients, mean age 30 years and average evolution time 26.3 months. Outpatient post-operative follow-up was on the average of 26.6 months. Level of response was good, 50% had full remission and a further 39% had good response. There was one death. The most common histopathology finding was thymic hyperplasia. Only 3 patients (6.5%) had benign thymomas; 5 (10.8%) had extra glandular thymic tissue: 2 in the perithymic fat and 3 in the pericardiac fat adjacent to the left phrenic nerve and aortal-pulmonary window. Conclusion: Treatment of MG by extended thymectomy is safe and efficient with high levels of complete remission. Extra glandular thymic tissue was found in some patients. As soon as diagnosis is completed, thymectomy is indicated together with plasmapheresis and medication, independent of age, onset of symptoms, and thymus pathology.

Keywords: Thymectomy/methods. Myasthenia gravis/pathology. Neuromuscular diseases/rehabilitation.

Castleman's disease is an atypical lymphoproliferative disorder of unknown etiology, which might be associated with various clinical conditions, including autoimmune diseases and malignant neoplasms. We report the case of a 72-year-old female patient who was referred to the thoracic surgery department of Getúlio Vargas University Hospital, in the city of Manaus, Brazil, for the resection of a posterior mediastinal tumor. Three months prior, the patient had been admitted to the ICU with signs of severe dyspnea, at which time she was diagnosed with myasthenia gravis. After the resection of the mediastinal tumor, the histopathological examination revealed hyaline vascular-type Castleman's disease, complicated by follicular dendritic cell sarcoma. At this writing, the patient was being treated with an anticholinesterase agent and corticosteroids for the control of myasthenia gravis.

Keywords: Giant lymph node hyperplasia; Dendritic cell sarcoma, follicular; Myasthenia gravis; Mediastinal diseases.

Background: The relationship between myasthenia and the thymus is evident and the current treatment of this condition includes thymectomy. However, a revision of our experience with thymectomy has revealed the necessity of a more radical technique. Objective: To analyze, retrospectively, myasthenia gravis patients who underwent videothoracoscopic radical thymectomy, emphasizing the advantages and drawbacks of the methodology, pathological findings and results related to disease control. Material and methods: Twenty-one myasthenic patients (18 females and 3 males, aged 17 to 51 years), underwent videothoracoscopic bilateral thymectomy associated to transverse cervicotomy for removal of the thymus gland and surrounding tissues, and right and left pericardiac fat tissues. Those tissues were separately sent to pathology analysis. The mean time of follow-up was 39.2 months. Results: There were no intra-operative deaths. Two patients (9.5%) suffered vascular injury, and one patient (4.8%) presented a low level permanent dysphonia. Nineteen patients (90.4%) are doing well, with none or low dose medications. Pathology studies showed 10 hyperplastic thymuses, 6 with involution and 5 with normal aspect. Ectopic thymic tissue was found in six patients (28.6%). Conclusion: Videothoracoscopic radical thymectomy offered a good control of myasthenia gravis. Additionally, ectopic thymus tissue was removed from some patients.

Keywords: Thorax. Surgery, video-assisted. Myastenia gravis. Thymectomy.

Objective: To determine the occurrence of exercise-induced bronchoconstriction and analyze cardiorespiratory response during maximal exercise in asthmatic patients. Patients and methods: Fourteen subjects with asthma (FEV1 of 86.3% predicted), as defined by the American Thoracic Society criteria were submitted to a maximal exercise test. Volume-flow curves were performed prior to progressive maximal exercise and seven and 15 minutes after it. Six patients (43%) showed a decline in FEV1 equal or greater than 15% after exercise (group I). The remaining patients constituted group II. Group I showed a FEV1 fall of 40.9% and 26.7%, seven and 15 minutes after exercise, respectively. In group II, there was a decrease of 2.6%, after 7 min and an increase of 1.2% after 15 min. At peak exercise, both groups reached heart rate above 91% of reference values; peak work was 82.7% and 62.5%, VO2max (mL/kg/min) 93.5% and 58,9% and VEmax 91.5% and 63.8%, respectively, in groups I and II. These differences were statistically significant. The correlation between the FEV1 fall rate (7 min post-exercise) and VEmax (% predicted) has showed a coefficient r = 0.8989 in group I and r = 0.3629 in group II. There was no correlation between delta VEF1 and VO2max (% predicted) in both groups. These findings showed that, in exercise-induced asthma patients, the occurrence of bronchoconstriction correlated with the level of maximal ventilation, but not with physical fitness.

Keywords: Exercise induced asthma. Bronchoconstriction. Tidal volume. Respiratory function tests.

Objective: Making the differential diagnosis between asthma and chronic obstructive pulmonary disease (COPD) based on the response to inhaled bronchodilators by means of spirometry is controversial.The objective of this study was to identify the most useful spirometric variables in order to distinguish between asthma and COPD. Methods: Retrospective study conducted from April of 2004 to January of 2006, comparing the spirometric parameters of 103 nonsmoking patients with asthma to those of 108 patients with COPD who were smokers for more than 10 pack-years. All of the patients included in the study were older than 40 and presented stable disease at the time of the test. Results: Initial forced expiratory volume in one second (FEV1) was the same in the two groups (pre-bronchodilator FEV1 = 51%). However, patients with COPD were older (66 ± 9 years vs. 59 ± 11 years, p < 0.001) and more frequently male (73% vs. 27%, p < 0,001).After the use of the bronchodilator, the median absolute difference in FEV1 was 0.25 L (range, −0.09 to 1.13 L) in patients with asthma and 0.09 L (range, −0.1 to 0.73 L) in those with COPD (p < 0.001).The highest sensitivity (55%), specificity (91%) and likelihood ratio (6.1) for asthma diagnosis was obtained when the percentage increase in postbronchodilator FEV1 in relation to the predicted FEV1 (Δ%predFEV1) was equal to or greater than 10%.Isolated significant increases in forced vital capacity were more common in patients with COPD. Conclusions: In patients over the age of 40 and presenting obstructive lung disease, a Δ%predFEV1 ≥ 10% is the best spirometric parameter to distinguish asthma from COPD.

Keywords: Spirometry; Respiratory function tests; Lung diseases, obstructive.

Idiopathic pulmonary arterial hypertension (PAH) patients with a positive response to acute vasodilator challenge and a clinical response to calcium channel blockers (CCBs) for at least one year are traditionally designated true responders. Nevertheless, little is known about a sustained response to CCBs over longer periods of time. We evaluated the loss of response to CCBs after long-term treatment in a cohort of idiopathic PAH patients previously classified as being true responders. Our data suggest that idiopathic PAH patients can lose clinical response to CCBs even after one year of clinical stability, reinforcing the need for constant multidimensional reevaluation to assess the need for targeted PAH therapies and to classify these patients correctly.

Keywords: Pulmonary hypertension; Vasodilator agents; Calcium channel blockers.

Objective: To use the forced oscillation technique to evaluate asthma patients presenting positive bronchodilator responses (confirmed through spirometry) and compare the results with those obtained in healthy individuals. Methods: The study sample consisted of 53 non-smoking volunteers: 24 healthy subjects with no history of pulmonary disease and 29 asthmatics presenting positive bronchodilator response, as determined through analysis of spirometry findings. All of the subjects were submitted to forced oscillation technique and spirometry immediately before and 20 minutes after the administration of salbutamol spray (300 g). The parameters derived from the forced oscillation technique were total respiratory resistance, total respiratory reactance, resistance extrapolated to the y axis, the slope of resistance, and dynamic compliance. The parameters measured in the spirometry evaluation tests were forced expiratory volume in one second and forced vital capacity. Results: In the control group, bronchodilator use produced a significant alteration in the resistance extrapolated to the y axis (p < 0.001), although no significant differences were observed in the slope of resistance or in dynamic compliance. Analysis of the asthma patients revealed significant differences between the prebronchodilator and postbronchodilator values for all spirometry and forced oscillation technique parameters. Values of p < 0.001 were obtained for all comparisons between the two groups. Conclusion: The modifications provoked by use of the forced oscillation technique were in direct concordance with the pathophysiology of the bronchodilator response in asthma patients, indicating that the forced oscillation technique could be useful as a complement to spirometry in these patients.

Keywords: Asthma; Bronchial hyperreactivity; Spirometry/methods; Bronchial provocation tests; Forced expiratory volume/physiology; Oscillometry

Objective: To assess blockade of matrix metalloproteinase (MMP)-2 and MMP-9, as well as the variation in FEV1, in patients with lymphangioleiomyomatosis (LAM) treated with doxycycline (a known MMP inhibitor) for 12 months. Methods: An open-label, single-arm, interventional clinical trial in which LAM patients received doxycycline (100 mg/day) for 12 months. Patients underwent full pulmonary function testing, a six-minute walk test, and quality of life assessment, as well as blood and urine sampling for quantification of MMP-2, MMP-9, and VEGF-D levels-at baseline, as well as at 6 and 12 months after the initiation of doxycycline. Results: Thirty-one LAM patients received doxycycline for 12 months. Although there was effective blockade of urinary MMP-9 and serum MMP-2 after treatment, there were no significant differences between pre‑and post-doxycycline serum levels of MMP-9 and VEGF-D. On the basis of their response to doxycycline (as determined by the variation in FEV1), the patients were divided into two groups: the doxycycline-responder (doxy-R) group (n = 13); and the doxycycline-nonresponder (doxy-NR) group (n = 18). The patients with mild spirometric abnormalities responded better to doxycycline. The most common side effects were mild epigastric pain, nausea, and diarrhea. Conclusions: In patients with LAM, doxycycline treatment results in effective MMP blockade, as well as in improved lung function and quality of life in those with less severe disease. However, these benefits do not seem to be related to the MMP blockade, raising the hypothesis that there is a different mechanism of action. (Brazilian Registry of Clinical Trials - ReBEC; identification number RBR-6g8yz9 [http://www.ensaiosclinicos.gov.br])

Keywords: Lymphangioleiomyomatosis; Doxycycline; Matrix metalloproteinases; Respiratory function tests.

Objective: Pulmonary rehabilitation (PR) improves exercise capacity in most but not all COPD patients. The factors associated with treatment success and the role of chest wall mechanics remain unclear. We investigated the impact of PR on exercise performance in COPD with severe hyperinflation. Methods: We evaluated 22 COPD patients (age, 66 ± 7 years; FEV1 = 37.1 ± 11.8% of predicted) who underwent eight weeks of aerobic exercise and strength training. Before and after PR, each patient also performed a six-minute walk test and an incremental cycle ergometer test. During the latter, we measured chest wall volumes (total and compartmental, by optoelectronic plethysmography) and determined maximal workloads. Results: We observed significant differences between the pre- and post-PR means for six-minute walk distance (305 ± 78 vs. 330 ± 96 m, p < 0.001) and maximal workload (33 ± 21 vs. 39 ± 20 W; p = 0.02). At equivalent workload settings, PR led to lower oxygen consumption, carbon dioxide production (VCO2), and minute ventilation. The inspiratory (operating) rib cage volume decreased significantly after PR. There were 6 patients in whom PR did not increase the maximal workload. After PR, those patients showed no significant decrease in VCO2 during exercise, had higher end-expiratory chest wall volumes with a more rapid shallow breathing pattern, and continued to experience symptomatic leg fatigue. Conclusions: In severe COPD, PR appears to improve oxygen consumption and reduce VCO2, with a commensurate decrease in respiratory drive, changes reflected in the operating chest wall volumes. Patients with severe post-exercise hyperinflation and leg fatigue might be unable to improve their maximal performance despite completing a PR program.

Keywords: Pulmonary disease, chronic obstructive/rehabilitation; Exercise therapy; Respiratory therapy.

Objective: To determine whether serum total IgE levels and total eosinophil counts have any relationship with the response to routine pharmacological treatment in patients with acute asthma. Methods: A cross-sectional study involving 162 patients with acute asthma. Serum total IgE levels, peripheral blood cell counts and eosinophil counts were determined. The treatment was adjusted for each patient according to the severity of asthma. Spirometry was performed at baseline and two weeks after the treatment. The patients were divided into two groups: high IgE (≥100 IU/mL) and low IgE (<100 IU/mL). We compared the two groups in terms of the relationships between baseline values and final values (percentage change) for the following parameters: FEV1, FVC, FEF25-75%, peripheral white blood cell counts and eosinophil counts. Results: There were no significant differences between the groups regarding the percentage changes of the studied parameters. Nor were there significant differences between the groups regarding FEV1, FVC, and FEF25-75% (% of the predicted values) at baseline. Conclusions: On the basis of these findings, we conclude that serum total IgE levels, peripheral white blood cell counts and eosinophil counts cannot predict the response to the pharmacological treatment of patients with acute asthma.

Keywords: Asthma/drug therapy; Eosinophils; Immunoglobulin E

Objective: Post-infectious bronchiolitis obliterans (PIBO) is a clinical entity that has been classified as constrictive, fixed obstruction of the lumen by fibrotic tissue. However, recent studies using impulse oscillometry have reported bronchodilator responses in PIBO patients. The objective of this study was to evaluate bronchodilator responses in pediatric PIBO patients, comparing different criteria to define the response. Methods: We evaluated pediatric patients diagnosed with PIBO and treated at one of two pediatric pulmonology outpatient clinics in the city of Porto Alegre, Brazil. Spirometric parameters were measured in accordance with international recommendations. Results: We included a total of 72 pediatric PIBO patients. The mean pre- and post-bronchodilator values were clearly lower than the reference values for all parameters, especially FEF25‑75%. There were post-bronchodilator improvements. When measured as mean percent increases, FEV1 and FEF25-75%, improved by 11% and 20%, respectively. However, when the absolute values were calculated, the mean FEV1 and FEF25-75% both increased by only 0.1 L. We found that age at viral aggression, a family history of asthma, and allergy had no significant effects on bronchodilator responses. Conclusions: Pediatric patients with PIBO have peripheral airway obstruction that is responsive to treatment but is not completely reversible with a bronchodilator. The concept of PIBO as fixed, irreversible obstruction does not seem to apply to this population. Our data suggest that airway obstruction is variable in PIBO patients, a finding that could have major clinical implications.

Keywords: Bronchiolitis obliterans; Infection/complications; Airway obstruction; Bronchodilator agents.

Objectives: To evaluate the self-reported degree of adherence to treatment in patients with cystic fibrosis (CF), investigating associations with characteristics of the disease and with the degree of adherence perceived by health professionals. Methods: This was a prospective, cross-sectional study involving patients with CF monitored at a Program for Adults with CF. The degree of adherence was evaluated using a questionnaire. Patients were divided into two groups: greater degree of adherence and moderate/poor degree of adherence. Clinical data, Shwachman-Kulczycki clinical score, Brasfield radiographic score and spirometry data were obtained for all patients. Results: Out of 38 patients studied, 31 (81.6%) were classified as presenting a greater degree of adherence and 7 (18.4%) as presenting a moderate/poor degree of adherence. The self-reported patient adherence score correlated with the clinical score (r = −0.36, p = 0.028). The self-reported patient adherence score (median = 0.79) was higher than that perceived by health professionals (median = 0.71, p = 0.003). A greater degree of adherence was self-reported for respiratory therapy (by 84.2%), exercise (by 21.1%), prescribed diet (by 65.8%), pancreatic enzymes (by 96.3%), vitamins (by 79.4%), inhaled antibiotic therapy (by 76.7%) and inhaled DNase (by 79.4%). Conclusions: Self-reported adherence of patients attending a Program for Adults with CF was good. The self-reported patient adherence score correlated inversely with the clinical score. Self-reported patient adherence was greater than the adherence perceived by health professionals.

Keywords: Cystic fibrosis; Patient compliance; Therapeutics.

Objective: To evaluate, using pulmonary function tests, the effectiveness of formoterol as a bronchodilator at 30 min after its administration in patients with poorly reversible COPD. Methods: A prospective study including 40 COPD patients not responding to the short-acting bronchodilator used in the spirometric test-variation of less than 200 mL and less than 7% of predicted in forced expiratory volume in one second (FEV1). All patients were classified as having stage II, III, or IV COPD (Brazilian Thoracic Society/Global Initiative for Chronic Obstructive Lung Disease) and presented FEV1 ≤ 70% of predicted value. The patients were randomized into two groups of 20, with similar clinical characteristics, receiving, via a dry powder inhaler, either formoterol or a placebo. The pulmonary function testing (plethysmography) was repeated at 30 min after formoterol or placebo administration. Results: In the formoterol group, the mean values obtained for FEV1, inspiratory capacity, and forced vital capacity were significantly greater than those obtained in the placebo group (p = 0.00065, p = 0.05, and p = 0.017, respectively), whereas that obtained for airway resistance was significantly lower (p = 0.010). Less pronounced differences were observed for residual volume, vital capacity and specific airway conductance, which were lower, higher and higher, respectively, in the formoterol group. Conclusions: In COPD patients not responding to the short-acting bronchodilator used in the spirometric test, formoterol promoted significant improvement in lung function at 30 min after of administration. Further studies are required to confirm whether formoterol can also be used as a medication for immediate relief of symptoms in COPD.

Keywords: Chronic obstructive pulmonary disease; Respiratory function tests; Bronchodilator agents.