Haemolytic anaemia caused by anti-Prafollowing rubella infection

Summary. A 24-year-old male was admitted to Kansai Medical University Hospital, complaining of fever, skin exanthema, jaundice, brown urine and lymphadenopathy. The patient was diagnosed as having haemolytic anaemia caused by a cold agglutinin following rubella infection. The cold agglutinin of the patient reacted strongly with group OI red blood cells (RBC), Oi cord RBC, Oi adult RBC and neuraminidase-treated RBC, and much weaker with protease (papain, ficin, bromelin)-treated RBC; it was identified as anti-Pra. Cold agglutinins of anti-Pra specificity following rubella infection in adults have rarely been reported.