Your client is a known case of Anemia who was admitted to medical ward for blood transfusion. The physician ordered 1 unit of packed red blood cells (PROC) for him. After 2 hours of commencing the...

Your client is a known case of Anemia who was admitted to medical ward for blood transfusion. The physician ordered 1 unit of packed red blood cells (PROC) for him. After 2 hours of commencing the transfusion, Mr. H vomited twice and reported having diarrhea. His vital signs were checked; Temp: 38.9 degree Celsius and BP 98/50 mm of Hg.

What might be the possible cause of the transfusion reaction your client has developed?