A rare case of Anti-Jk3 Alloimmunization

Abstract Introduction/Objective The Kidd blood group system was discovered in 1951 and consists of two antithetical antigens, Jka and Jkb, in addition to a third high-incidence antigen, Jk3. Jk null, also known as Jk(a-b-), is an extremely rare blood group in which all Kidd antigens are absent. Jk is a urea transporter found in the renal medulla, and Jk-deficient individuals are unable to concentrate urine to its maximum concentration. If these individuals are exposed to the Jk antigen via transfusion or pregnancy, they are able to produce antibodies against the Jk3 antigen with a high incidence. Jk3 is expressed in over 99.9% of the blood donor pool, which has severe clinical implications and complicates transfusion. Methods/Case Report CASE PRESENTATION: A 68-year-old male was admitted to the Stanford Medical Center with chronic right midshaft tibia osteomyelitis and a sinus drainage tract for a right tibial diaphysectomy. His test for antibodies was positive. Plasma from the patient is reactive with all tested cells except auto control, AHG in PEG, and solid phase. Phenotyping yielded negative results for Jka and Jkb, suggesting that the antibody is Jk3. Anti-Jk3 was eliminated by adsorption and rendered nonreactive. Results (if a Case Study enter NA) NA Conclusion Anti-Jk3 should be suspected in a previously pregnant or transfused patient during antibody screening and identification if it demonstrates the pattern of an antibody reacting to all cells in the panel, i.e., reacting to a high- frequency antigen with negative autocontrol. Awareness on the part of blood bank personnel regarding the variability of the blood group phenotype and the capricious nature of Kidd antibodies may aid in the improved management of these patients. It is recommended that patients with rare antibodies carry an antibody ID card indicating the rare antibody they have to prevent further exposure. A patient may be advised to undergo an autologous transfusion. Fortunately, the patient’s procedures were uncomplicated, so a blood transfusion was unnecessary. Awareness on the part of blood bank staff regarding the variability of the blood group phenotype and the unpredictability of Anti-Jk3 may aid in improving patient care. To prevent further exposure, it is recommended that patients with rare antibodies carry an Antibody ID card indicating the rare antibody they possess.Jk3 antigen blood donors are underrepresented in the general donor pool. It is recommended to develop a systematic recruitment for Jk3 antigen donors.