[Transfusion management of patients with alloanti-Gerbich antibodies: case report]

Transfusion management of patients who are alloimmunized against high-prevalence erythrocyte antigens is often problematic. Strategy management depends, not only on the specific clinical circumstances of the patient, but also on the acceptable time frame. In patients without clinically significant antibody incompatible transfusion it may be less harmful than delaying medical intervention.

We report a 57-year-old female from Libya, blood group O, RhD-positive, who was treated at the Institute of Cardiovascular Diseases of Vojvodina. At the Blood Transfusion Institute of Vojvodina, during pretransfusion testing an IgG alloantibody of unknown specificity was determined. A total of 200 blood units (O, RhD-positive) were crossmatched, but positive reactions indicating that the donor units were incompatible for that specific patient. By testing the patient's family members in Tripoli, six compatible blood units were found and applied during and after surgery. Due to the deterioration of the patient's condition a rapid transfusion was required; however cross-match compatible blood was not available. After a biological cross-match to predict the clinical significance of this antibody, 12 units of erythrocytes with the lowest positive cross-match reactions, were transfused to the patient without any adverse effects. Good tolerance of the units suggested that the present antibodies were not clinically significant. Later on, a rare alloantibody directed to the high frequency Gerbich blood group antigens was identified by the Foundation Central Laboratory, Blood Transfusion Service in Bern, Switzerland.

In cases of emergency patients with alloantibodies against high frequency Gerbich, when autologous or compatible alogenous transfusion is unavailable, blood with the lowest positive cross-match reaction could be transfused if the biological cross-match is negative. Formation of a national register of donors with rare blood groups and their connection with international registers is of crucial significance in the management of patients requiring antigen negative blood otherwise unavailable from routine blood banks.