Duffy a and b positive

This code indicates a specific red blood cell antigen status, where both the Duffy a (Fy(a)) and Duffy b (Fy(b)) antigens are present on the patient's red blood cells. This phenotype is significant in transfusion medicine and for understanding susceptibility to certain parasitic infections.

Use this code when documentation explicitly states a patient is "Duffy a and b positive" or "Fy(a+b+)." This information is often found in laboratory reports from blood typing or cross-matching procedures, particularly in the context of pre-transfusion testing or workups for hemolytic disease.

• Ensure the documentation clearly specifies positivity for both Duffy a and Duffy b antigens.
• This code is typically used as a secondary diagnosis to provide additional clinical detail, not usually as a primary diagnosis.
• Do not use if only one Duffy antigen is positive or if the status is unknown.