Higher prevalence of wheezing and lower FEV1 and FVC percent predicted in adults with sickle cell anaemia: A cross-sectional study

House Dust Mite-Induced Allergic Lung Inflammation Is Not Exacerbated in Sickle Cell Disease Mice

AIM

Asthma appears to be a common comorbid condition in children with sickle cell disease (SCD), and such individuals may be at a higher risk for increased morbidity and mortality. However, several reports have indicated that asthma severity is not particularly high in those with SCD, and airway hyperreactivity and wheeze may be independently associated with SCD. In SCD mice, exacerbated allergic airway disease (AAD) has been observed in response to the model antigen ovalbumin (OVA). We sought to determine if allergic lung inflammation is also exacerbated in SCD mice when they are exposed to the human allergen, house dust mite (HDM).

METHODS AND RESULTS

Eosinophil counts in bronchoalveolar lavage fluid were determined by cytocentrifugation and increased in both wild-type (WT) and SCD mice after acute exposure to a high dose (25 µg) of HDM, which then decreased in chronically exposed mice. WT mice exposed to a low dose of HDM (1 µg) followed the same pattern of eosinophil flux, but SCD mice did not induce much eosinophilia after acute exposure to HDM. As was observed in previous studies, lung lesions similarly increased in severity in both WT and SCD mice after acute exposure to HDM, which remained elevated after chronic exposure. Furthermore, serum HDM-specific IgE titers similarly increased and selected serum cytokines were similar in both WT and SCD mice.

CONCLUSION

These results contrast with previous reports of exacerbated AAD in SCD mice exposed to OVA and support the alternative hypothesis that asthmatic responses are normal in those with SCD.

Lower than expected elevated tricuspid regurgitant jet velocity in adults with sickle cell disease in Nigeria

Background

Cardiopulmonary disease is a major cause of morbidity and mortality in persons with sickle cell disease (SCD). Tricuspid regurgitant jet velocity (TRJV) and predicted forced expiratory volume in 1 s (FEV1%) predicted are independently associated with death in SCD. The goal of this study was to determine the prevalence of elevated TRJV and the association, if any, between TRJV and FEV1% predicted among persons with sickle cell anaemia (SCA) in Nigeria.

Methods

Using a cross-sectional design, we enrolled 100 adult Nigerians (≥15 y) with SCA. We screened participants using Doppler echocardiogram to determine their TRJV and assessed their lung function with spirometry.

Results

The prevalence of elevated TRJV was 6%, with 74% of participants having low FEV1% predicted (<70%). TRJV was negatively correlated with FEV1%, but this finding was not statistically significant (Spearman's ρ=-0.0263, p=0.8058).

Conclusions

We found a low prevalence of elevated TRJV and a trend in association between TRJV and FEV1% predicted in Nigerian adults with SCA. Our findings underscore the need to explore further the relationship between SCD and cardiopulmonary disease in adults.

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

OBJECTIVE

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.

RESULTS

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.

CONCLUSIONS

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.