identification of first patient with rh null phenotype in southeast iran

Background and aims: rhnull, with an estimated incidence of one per 6,000,000 individuals, is an extremely rare disorder with an autosomal recessive pattern of inheritance that is more common in societies with a high rate of consanguinity. materials and methods: in this study, we report the first case with rhnull, a blood group phenotype in southeast iran, which was diagnosed during pretransfusion testing. results and conclusions: a 21-year-old woman with a positive parents' consanguineous marriage was found to have an unusual reaction with all packed red blood cell units during routine pretransfusion cross-match testing in the hospital. the patient's serum was reacted with all screening and identification panel cells, suspected to have an alloantibody against a common antigen or multiple alloantibodies against her absence antigens. further studies revealed negative results for c, c, e, and e, which are highly suspected of rhnull phenotype. confirmatory assessments were performed, including adsorption and elution studies and rh phenotyping of patients, along with known positive and negative controls. due to the blood requirement of the patient, we performed serological studies on the patient's family members and found that her sister also has a rhnull phenotype. blood transfusion from her sister's donated units was performed, and the pregnancy was ended without any complications. finally, due to the rarity of the rhnull phenotype, early identification of individuals and autologous or compatible allogeneic blood transfusion should be planned prior to selective or emergency surgeries.