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 allomtibody reacting at 37 degrees 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-LWa was detected only by a two-stage papain technique. These results suggest that the patient had a transient depression of LWa with a concurrent anti-LWa.