α-HUS Patient as a Renal Transplant Recipient - A Case Report

Abstract

Background: α-HUS is a rare cause of ESRD. The problem arises during selecting patients for renal transplantation, in whom ESRD developed due to α-HUS. In such cases, genetic testing should be performed (C3, CFH-, CFI- and MCP deficiency). A risk of recurrence of α-HUS after kidney transplantation (ktx) is the highest in the first 6 months and depends on the type of defect (the highest risk ˜ 80% for CFH and CFI mutations, ˜ 20% MCP). CNI-avoidance regimen does not reduce the risk of recurrence. In our country living donation for ESRD-patient with α-HUS is not recommended. Kidney transplantation from a cadaveric donor is acceptable, although there is a high risk of recurrence of the primary disease and graft failure. We present the cases of three brothers with ESRD in course of α-HUS with family HUS-history; two of them were transplanted, but due to the lack of real opportunities, genetic testing proving α-HUS was not performed. Description: The first brother, 21-year-old, with no previous signs of disease, suddenly developed hemolytic anemia, jaundice and AKI. Died in 4 weeks. Six years later, the second brother, aged 27, developed the same signs and symptoms. Renal biopsy revealed TMA. We conducted plasmapheresis (17 sessions) but with no renal improvement. Patient was referred to hemodialysis. Two years later, the third brother developed HUS and AKI. Due to thrombocytopenia renal biopsy was not performed. Plasmapheresis and FFP infusions were started, but renal function did not improved and hemodialysis were continued. The patient was highly motivated to ktx so he was referred to pretransplant assessment. Unfortunately, genetic testing for α-HUS is not available in our country due to economical reason we did not perform genetic testing abroad. Patient was informed about the increased risk of graft loss and underwent ktx from cadaveric donor with immunosupressive regimen: steroids+tacrolimus+MMF. Three months after ktx in protocol biopsy we found no signs of TMA. Currently, 14 months after ktx, graft function is stable, tacrolimus concentration is 4-5 ng/ml, serum creatinine concentration is 1,7 mg/dl. Then, the second brother underwent ktx from cadaveric donor (immunosupressive regimen: steroids+tacrolimus +MMF+basiliximab) with immediate graft function. After three months of follow-up graft function remains stable, serum creatinine concentration is 1,3 mg/dl, tacrolimus concentration is 5-6 ng/ml, protocol biopsy in 3 months after ktx revealed normal kidney structure. Discussion: The cases illustrate the difficulties in application for ktx α-HUS-patient. We did not manage to perform necessary α-HUS genetic testing, what became a serious concern. Uneventful course after ktx might be determined by the presence of mild defects of complement or other cause, what is elusive for the authors. Conclusion: The lack of widespread access to specialized α-HUS genetic testing impeded qualification for ktx and forces the doctor to make decisions based on clinical experience and personal intuition.