Sickle cell anemia was a rare disease in Chile, especially in adults, however the recent immigration wave from Haiti is changing this scenario. We report a 29 year old black female from Haiti with a non-disclosed history of sickle cell anemia. She was transfused with two units of red blood cells, found unconscious and with jaundice five days later and admitted to the hospital. On admission she had a hemoglobin of 3.3 g/dL, a total bilirubin of 5.08 mg/dL, a LDH of 1306 Ui/L. She was transfused again, worsening her condition. An alloimmunization and delayed hemolytic reaction was suspected. A direct Coombs test was positive. She was treated with steroids and her serum hemoglobin rose progressively.Sickle cell anemia was a rare disease in Chile, especially in adults, however the recent immigration wave from Haiti is changing this scenario. We report a 29 year old black female from Haiti with a non-disclosed history of sickle cell anemia. She was transfused with two units of red blood cells, found unconscious and with jaundice five days later and admitted to the hospital. On admission she had a hemoglobin of 3.3 g/dL, a total bilirubin of 5.08 mg/dL, a LDH of 1306 Ui/L. She was transfused again, worsening her condition. An alloimmunization and delayed hemolytic reaction was suspected. A direct Coombs test was positive. She was treated with steroids and her serum hemoglobin rose progressively.