Patient: 30 y/o AAF. Brought in for labor check/delivery. Initial specimen drawn at 1955, tested on ProVue: anti-A: 0 anti-B: 0 anti-D: 4+ A1 cells: 0 B cells: 4+ BT: NRD Second specimen drawn at 2030, tested on ProVue: anti-A: ? anti-B: 0 anti-D: 4+ A1 cells: 0 B cells: 4+ BT: NRD Third specimen, drawn 2319, tested on ProVue: anti-A: 3+ anti-B: 0 anti-D: 4+ A1 cells: 0 B cells: 2+ BT: A Pos. This morning a fourth sample was drawn and all four were performed by manual method. Results were the same across the board except for with the third specimen: anti-A: 0 IS / 1+mf 15min RT (2+mf for specimen #3) anti-B: 0 IS / 0 15min RT anti-D: 3+ A1 cells: w-1+ IS / 2+ 15 min RT B cells: 4+ IS / 4+ 15min RT A mini cold panel showed only anti-A1 activity in the patient's plasma. Any idea as to why one of the specimens would give such different results? Mislabel/Misidentification seems unlikely.