Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0039730 (thalassemia)
 10,305 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Progressive tissue iron deposition from multiple blood transfusions is common in beta-thalassaemia and pulmonary iron deposition may result in parenchymal damage. The objectives of this study were to: 1) determine the predominant pulmonary dysfunction in patients with thalassaemia major; and 2) demonstrate that parenchymal disease, if present, is at the level of the alveolocapillary membrane. Fourteen thalassaemia major patients (13 nonsmokers) receiving regular blood transfusion and without any history of chronic respiratory disease were recruited. Pulmonary function tests and echocardiography were performed before the scheduled transfusions. Three patients with the most restricted lung function were selected for high resolution computerized tomography (CT) of the lungs. One patient had an obstructive pattern with a forced expiratory volume in one second as percentage of forced vital capacity (FEV1/FVC) of 71%. Four patients demonstrated a restrictive pattern, as defined by total lung capacity (TLC) less than 80% predicted with normal FEV1/FVC%. Twelve patients had pulmonary transfer factors for carbon monoxide (TL,CO) below 80% pred, even after correction for the anaemia, indicating parenchymal disease. Eight of these 12 patients had alveolocapillary membrane defect, as demonstrated by a gas transfer factor of the pulmonary membrane (Tm) less than 80% pred. Mean resting arterial oxygen saturation was 95 +/- 2 (range 92-98) %. Eleven patients had oxygen desaturation of 5% or more during exercise on a bicycle ergometer, consistent with interstitial lung disease. There was no clinical or echocardiographic evidence of heart failure. Percentage predicted TLC was inversely correlated with age (r = -0.547; p = 0.043). Both percentage predicted TLC and TL,CO were not correlated with iron burden or desferoxamine ratio. High resolution CT in the three selected patients showed no evidence of pulmonary fibrosis. We conclude that thalassaemia major patients have a predominant restrictive lung dysfunction with pulmonary parenchymal disease and alveolocapillary membrane block. The restrictive and interstitial lung disease could not be accounted for by iron loading or pulmonary fibrosis in our patients.
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PMID:Lungs in thalassaemia major patients receiving regular transfusion. 883 48

Pulmonary dysfunction represents one of the least studied complications in thalassemic patients. Probably, it is due to the absence of pulmonary symptoms. There are few works in the literature, and contradictory results have been published. The aim of this study was to define the spirometric pattern and the possible causes of lung impairment by testing bronchoalveolar lavage (BAL) with pathological pulmonary function tests (PFTs). Furthermore, diffusion capacity tests for carbon monoxide corrected for hemoglobin value (Dco*) were performed. We studied 48 thalassemic patients (27 F and 21 M), with an age range from 8 to 23 years, divided into two groups on the basis of PFTs results. Thus, group A was formed by 16 patients with restrictive spirometric patterns of whom 14 had also reduced Dco* values and group B consisted of 32 patients with normal PFTs and Dco* values. Patients of group A underwent chest high-resolution computing tomography (CHRCT) and BAL whose fluid was analyzed by microbiologic and cytological assays. A pathological CHRCT picture was present in 8 patients. Nine out of 16 patients who accepted to undergo BAL had a chronological age greater than 17 years with a mean bone age of 13.9 years. BAL results showed lymphocyte alveolitis in 6 patients and a normal cytogram in 3, while alveolar iron-laden macrophages were present in 4 out of 6 patients with alveolitis and 2 out of 3 patients with normal cytogram. Moreover, all examined BAL fluids showed a normal CD4/CD8 ratio, while only 2 patients showed an altered serum CD4/CD8 ratio. We demonstrated the presence of (1) lung-restrictive syndrome in 16 of the oldest thalassemic patients; (2) lymphocyte alveolitis in 6 patients, and (3) a picture of interstitial fibrosis by CHRCT in 8 of them. All these data are suggestive of a diagnosis of interstitial lung disease secondary to thalassemia. BAL helped to identify the presence of alveolar iron-laden macrophages that represented a local defense mechanism against free iron. This latter finding therefore might be the primary cause of the lung impairment promoting an oxidative damage. Further studies are needed to investigate this hypothesis and therapeutical potentials.
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PMID:Evidence of lymphocyte alveolitis by bronchoalveolar lavage in thalassemic patients with pulmonary dysfunction. 1083 52