Very high serum ferritin levels in three newborns with Kawasaki-like illness.

Kawasaki disease (KD) is an inflammatory condition of unknown etiology that affects children, with a peak incidence in the second year of life. KD is uncommon in the first year of life and is rare in the newborn period. The present report describes three newborn infants who were admitted to hospital with fever and nearly identical clinical features of generalized inflammation. The presentations did not meet the criteria for KD; however, all three patients responded promptly and completely to intravenous immunoglobulin treatment. Specifically, the association of these presentations with very high levels of serum ferritin is reported. The authors propose that this clinical syndrome represents a variant of KD, and that serum ferritin level may be a useful marker in diagnosing KD and its variants. Additionally, the association of this clinical picture with very high serum ferritin levels raises the possibility of a link with hemophagocytic lymphohistiocytosis.