Purpose: To describe the findings and cause of anemia and jaundice in a 2-year-old boy.
Patient and methods: This boy was admitted with a hemoglobin of 7.8 g/dL, a bilirubin of 1.8 mg/dL, and increased urobilinogen.
Results: On the second day after admission, hemolytic anemia associated with an anti-I cold agglutinin was diagnosed, which was transient and recovered without any treatment.
Conclusion: This is a very rare complication of chickenpox; only five cases have been previously reported and these were all characterized by anti-Pr cold agglutinin with hemolytic anemia after the onset of chickenpox. We report the first case of hemolytic anemia associated with an anti-I cold agglutinin during the incubation period of chickenpox.