Prevalence, Disease Manifestations and Outcomes of Paediatric Sickle Cell Anaemia in Calabar, Nigeria: A Single Center 6-Year Review

Background: The burden of sickle cell anaemia (SCA) is worsening globally. Recognition of paediatric SCA burden is vital to comprehending the overall SCA burden. Aim was to determine the prevalence, disease manifestations and outcomes of paediatric SCA. Materials and Methods: It was a retrospective study of all children with SCA, 0.5 year (6months) - 17 years old, managed from 2018 through 2023. Data obtained were sex, age at first visit per year, diagnoses and date per visit, location (clinics or emergency-room) of visit, intervals between visits, and death. Disease manifestations per subject were summarized into diagnosis while default was defined as >3 months visit interval. Results: Of the 532 subjects, 55.6% were males with overall median (interquartile [IQR]) age on first visit of 9 (5 - 13) years. On average, paediatric SCA constituted 4% of first visits per year. There were 252 sick visits per year, 544 diagnoses per year and 146 hospitalisations per year. Commonest diagnosis in emergency-room and clinics were bone pain crises (46.2%) and steady-state (48.5%), respectively. The 11 - 17-year-olds were more likely to have bone pain crises than 0.5 - 4-year-olds (Odds Ratio [OR] 0.381; 95%CI: 0.487-0.787) and 5 - 9-year-olds (OR 0.298; 95%CI: 0.573-0.861). They were also more likely to have avascular necrosis than the 0.5 - 4-year-olds (OR 0.789; 95%CI: 0.047-0.938) and 5 - 9-year-olds (OR 0.777; 95%CI: 0.064-0.781). Overall median (IQR) default time was 6 (5 - 7) months with more defaults (85.1%) than compliants (14.9%) (p<0.001) while 0.56% died. Conclusion: The overall prevalence of Paediatric SCA in the region is 4% with approximately one hospitalisation per sick visit and more than one diagnoses per visit. There is a high default rate but a low mortality rate (0.56%). Sustained improvement in the management of SCA, from childhood through adulthood, may help alleviate the increasing burden of the condition.