Pulmonary Dysfunction in Beta Thalassemia.

Abstract

Thalassemia is one of the commonest hereditary hemolytic anemia. Survival of patients with thalassemia major has greatly improved during recent years, with the introduction of moderate -transfusion programs and chelation therapy with subcutaneous Desferal (deferrioxamine) and/or Kelfer (Deferiprone). The repeated transfusions in thalassemics lead to deposition of iron in different tissues, leading to damage and dysfunction of various systems. Iron deposition is also reported to exist in the lungs at autopsy. Although lung impairment in thalassemic patients has been reported in the 1980's, yet it is one of the most under evaluated and functionally not well-characterized complication. Since there have been contradictory results reported in literature ranging from restrictive spirometric pattern to an obstructive one, and there is total paucity of data from India, this study was designed to find out the pulmonary function tests of the beta thalassemic patients attending our hospital. A total of 30 cases of beta thalassemia major who were attending the thalassemia clinic at Sir Ganga Ram Hospital were taken up for the study after a written informed consent. These patients were on moderate -transfusion regimen, maintaining a hemoglobin concentration of more than 9 gm %. Patients with asthma and cardiac disease were excluded. Pulmonary function tests done included Forced vital capacity (FCV), Forced expiratory volume in one second (FEV1), FEV1/FVC percent (FEV1 %) and peak expiratory flow rate (PEFR). Results were interpreted as obstructive, restrictive and normal pulmonary Function test (PFT). The data was analyzed using software SPSS version 10. We included three age groups in our study, with total 30 patients in all. Age group 6–10 yr had 9 patients (mean Serum ferritin 2301 ng/ml), 11–15 yr had 11 children (mean Serum ferritin 3315) and >15 yr had 11 children (mean Serum ferritin 5147 ng/ml) in the study. Mean age was 14.46 with standard deviation of 6.75 (mean ferritin was 3682 ng/ml). Overall out of 30 patients 13 had normal PFT and 17 had abnormal PFT (1 had obstructive PFT and 16 had restrictive PFT). In the age group of 6–10 years 7 had normal and 2 had abnormal PFT and in age group 11–15 yr 3 had normal and 6 had abnormal PFT and in age group >15 yr 3 had normal and 8 had abnormal PFT. Of 17 patients on chelation with Desferal alone 11 had normal and 6 had abnormal PFT. 6 patients were on Kelfer alone of which 1 had normal and 5 had abnormal PFT. Of 7 patients who were on both Desferal and Kelfer, 1 had normal and 6 had abnormal PFT. All patients on Kelfer or Kelfer + Desferal aged >10 years except one which may explain reason for increased number of abnormal results in this group. Critical age above which abnormal results were higher was 11.5 years. Mean Ferritin in patients with normal PFT was 2456 ng/ml and 4621 ng/ml for patients with abnormal PFT. (p value 0.037) We found a negative Pearson correlation between FVC (% of predicted) with increasing ferritin (p value 0.038). There was no difference detected between pre and post transfusion PFT results by using paired t test (p value 0.973). In conclusion the major pulmonary dysfunction in our study group is that of restrictive type. The abnormal PFT were found in older age group. FVC was negatively co-related with increasing ferritin level. The number of abnormal results was higher when the serum ferritin was > 4000 ng/ml and blood transfusion had no effect on the PFT.