OBJECTIVETo identify the side effect of all-trans retinoic acid (ATRA), and improve early therapeutic response in patients with acute promyelocytic leukemia (APL).

METHODThe first case of Sweet's syndrome (SS) developed in a APL patient treated with ATRA was reported in mainland of China, and reviewed correlative literature.

RESULTSOnly 14 cases of SS associated with ATRA therapy in APL have been reported in the literature, including the present case. The median age was 49.5 years (9 -84) and 10 were women and 4 men. Of them, SS was restricted to the skin in 10 case, the other 4 muscle, fascia, kidney, and lung were involved. SS appeared after a median of 18 days of ATRA therapy (6 - 34 days). The median WBC count was 7.05 (0.80 - 23.00) x 10(9)/L. Four patients continued with the ATRA therapy without interruption, 13 patients treated with steroids and 12 responded. One patient improved without any treatment. Two cases of SS developed retinoic acid syndromes after ATRA therapy.

CONCLUSIONSweet's syndrome is a rare adverse effect of ATRA, and has similar features with inflammatory or infective dermatosis. The corticosteroids treatment could improve the systemic and cutaneous symptoms. When ATRA therapy was restarted after SS subsided, no recurrence of rashes was observed.