A Case Report of Occult Weak 'A' Subgroup: An Important Message for Renal Transplant Physicians

Accurate ABO grouping is the cornerstone of a successful ABO-compatible organ transplant. While conventional methods identify blood groups accurately in most cases, rare and weak blood groups could occasionally be misread/missed. Weak A subgroups such as A3, Ax, Aend, Am, Ay, and Ael are often mistyped as group O. We present one interesting case of 'weak A' subgroup in a renal transplant donor, who was wrongly typed as 'O' Rh D positive by conventional grouping techniques. It was a near miss as the donor was almost selected for transplant for the patient with blood group B positive.