C4A and Schnyder corneal dystrophy: The reason for relatively higher morbidity and mortality among children with SCD is complex and had been related to defective immune functions such as impaired phagocytosis,9 reduced C4 and C3, increased C1 inhibitor, reduced C3 activator,10 defective neutrophil migration/chemotactic activity and lymphocyte transformation,11 and inadequate antibody production due to functional asplenia, which make them susceptible to infections with encapsulated organisms such as Escherichia coli, Streptococcus pneumonia, and Salmonella species.12–16