An example of anti-LWa in a 10-month-old infant

Blood samples from a 10-month-old male infant requiring transfusion were found to contain an alloantibody reacting at 37°C in saline, by indirect antiglobulin test (IAT), and with a manual polybrene technique. Preliminary results suggested anti-D and another weaker reacting antibody, but the patient had been previously transfused with only D– blood. His serum reacted more weakly by IAT against red cells treated with 0.2M dithiothreitol (DTT), and one D+, LW(a–) sample was nonreactive. The patient’s red blood cells (RBCs) typed as B, D–, LW(a–), K–, Fy(a–). Due to the age and clinical status of the child, ⁵¹Cr survival studies were not performed. One pediatric unit of D–, K–, Fy(a–) blood was transfused uneventfully; the expected increment of hemoglobin was achieved. Repeat testing 3 months later showed a weakly positive DAT, the patient’s RBCs typed as LW(a+), and anti-LW^a was detected only by a two-stage papain technique. These results suggest that the patient had a transient depression of LW^a with a concurrent anti-LW^a. Immunohematology 1994;10:127–129.