Although sickle cell disease (SCD) and systemic lupus erythematosus (S
LE) are two distinct chronic diseases, many clinical features are comm
on to both conditions, We describe a young patient who had a mild clin
ical course of SCD until SLE developed when he was 15 years old. His i
nitial manifestations of SLE including fever, chest pain, and lung inf
iltration with pleural effusion were thought to be complications of SC
D, However, a deteriorating clinical course, presence of facial and tr
uncal rash, and persistent pleural effusion led to the diagnosis of SL
E, We compare our case and the 10 previously reported cases and discus
s the possible association of complement defects and the pathogenesis
of SLE in patients with SCD. Our report illustrates the importance of
considering other disease processes when clinical features are atypica
l of SCD.