HLA Antibodies in an Untransfused Male - Unexpected Reactivity Explained by Taking a Careful History

Abstract

Introduction: HLA antibodies are stimulated primarily by exposure to non-self HLA through organ transplantation, blood transfusion, or pregnancy. The occurrence of HLA antibodies in untransfused, untransplanted male subjects has been assumed to be a naturally occurring phenomenon in the absence of exposure to HLA. Patient and methods: A 44 year old man presented to a renal unit with hypertension and progressive renal failure. Renal biopsy showed severe tubular atrophy and no primary glomerulonephritis. Despite control of hypertension his serum creatinine rose from 394 umol/l on presentation to 428 umol/l six months later and he was worked up for living donor renal transplantation from his brother. Results: On screening for HLA antibodies he was found to have donor specific antibodies detected by screen and single antigen beads (MFIs:- A1 2000u, C7 1500u, DQ7 500u) and also other HLA antibodies (A31 5500u, DP23 4000u). Review of the history indicated he had previously been fit and well, with no hospital admissions and no question of administration of therapeutic blood products at any time of his life. However, he had been active for some years as a bare knuckle cage fighter. Cage fighting is a form of ‘all in’ combat with an opponent in a boxing ring enclosed in a wire cage. During these contests it was apparently common to suffer cuts on the hands and for the hands to be covered with an opponent's blood. Transplantation was performed after 2 sessions of double filtration plasmapheresis, and there was good function with no rejection. Post-transplant antibody monitoring showed no changes in the antibodies to Class 1, but the donor specific DQ7 antibody rose from MFI 500u to 3250u. Conclusion: In this patient the only documented source of HLA sensitisation was exposure to blood through cage fighting, and this underlines the importance of taking a careful history in any patient who presents with unexpected HLA antibody reactivity. Sensitisation to HLA through this route has not, to our knowledge, been previously reported.