Prevalence of pulmonary hypertension in children with sickle cell disease

Abstract

Background: To determine the prevalence of elevated pulmonary artery pressures and associated risk factors in children with sickle cell disease. Methods: A descriptive and cross sectional observational study was done over the period of 12 months (March-2013 to Feb-2014). All patients between the age group of 5 to 18 years diagnosed to have Sickle Cell Syndromes were included. A complete physical examination was performed and the details of patient’s age, age at diagnosis, age at first transfusion, frequency of transfusion, history of sickling crisis including the type and number of crisis were analyzed. Investigations done were complete hemogram with reticulocyte count, liver function tests, renal function tests, chest radiograph, electrocardiogram and a 2D echocardiogram. Quantitative data was analyzed by proportion and Chi square test. Results: Total 50 patients (30 males, 20 females) were enrolled in the study between the age group of 5-18 years with the mean age 11.3 ± 3.7 years. Overall prevalence of pulmonary hypertension (PHT) was 38%. Mild PHT (TR Jet velocity 2.5 to 2.9m/second) was found in 12 (24%) patients, 7 (14%) patients had moderate to severe PHT (TR jet velocity >3 m/second).Elevated tricuspid regurgitant jet velocity was more in patients with Hb-SS disease (38.6%) as compared Hb-S/β+ thalassemia (36.6%). A high reticulocyte count (p=0.036), low hemoglobin (p=0.046), increased number of crisis (p=0.048), more frequent packed red cell transfusions (p=0.043), high LDH (p=0.045) and a high bilirubin levels (p=0.041) were significantly associated with elevated pulmonary artery pressures. There was no difference in age of presentation, gender, age of first packed red cell transfusion between patients with and without elevated PHT. Conclusions: High pulmonary artery pressures do occur in children with sickle cell disease. Screening by echocardiography can lead to early detection and intervention.