What is the likely ABO type of a patient with test results showing Ael?

The ABO type of a patient with test results showing Ael is classified as Ax. The "Ael" phenotype indicates that the patient carries the "A" antigen, but it is weaker than what is typically seen in the A1 or A2 subgroups. The "l" represents an alteration in the expression of the A antigen.

Specifically, Ax individuals express the A antigen on their red blood cells but may have lower or altered antigen density compared to A1 individuals. The Ax phenotype is characterized by specific serological properties, such as reacting weakly with anti-A1 but typically reacting with anti-A. This weak reaction can lead to confusion with other ABO types, further reinforcing why the Ax designation fits here.

In summary, the presence of the A antigen with a low level of expression aligns with the Ax classification, distinguishing it from the more common A1 or A2 types, which show stronger reactions.