Correlates of Pulmonary Function in Children with Sickle Cell Disease and Elevated Fetal Hemoglobin

The current study was carried out to compare pulmonary function tests (PFTs) in pediatric Kuwaiti sickle cell disease (SCD) patients to age-matched normal controls and to investigate the association of PFTs with selected clinical and laboratory parameters. Subjects andMethods: There were 38 patients with SCD and 36 controls in the study. The patients were recruited from the Pediatric Hematology Clinics of Mubarak Al-Kabeer and Al-Amiri Hospitals, Kuwait, and were studied in steady state. The controls were healthy, non-sickle cell siblings of the patients. Forced expiratory volume in 1 s (FEV1), forced vital capacity (FVC), total lung capacity, and other PFT parameters were obtained using a constant-volume, variable-pressure, body plethysmograph. Hemoglobin, fetal hemoglobin, serum bilirubin, and lactate dehydrogenase were determined using standard methods.

The mean ages of the patients and controls were 10.5 ± 3.2 and 10.5 ± 3.5 years, respectively. The FEV1% predicted of 84.1 ± 15.4% among the patients was significantly lower than the 92.1 ± 11.8% in the controls (p = 0.003). The FVC% predicted was also significantly lower (p = 0.022) in the patients than in the controls, although the values were generally within the normal range. There was no association of FEV1 with pain phenotype, acute chest syndrome (ACS), or blood transfusions. Also, there was no significant correlation with reticulocytes, bilirubin, or lactate dehydrogenase.

In this study, changes in PFT, especially FEV1, developed early in the SCD patients. There was no demonstrable association with frequent vaso-occlusive crisis, ACS, and other variables. Hence, there is a need for follow-up studies with serial PFTs to identify vulnerable patients, who might need intervention to prevent early mortality.