Recurrence of 2,8-dihydroxyadenine Crystalline Nephropathy in a Kidney Transplant Recipient: A Case Report and Literature Review

We herein report the case of a kidney transplant patient with recurrence of obstructive nephropathy that was not diagnosed as adenine phosphoribosyltransferase (APRT) deficiency until gene testing identified a pathogenic homozygous variant three years after renal transplantation. Subsequently, the patient was treated with allopurinol, and the allograft function increased progressively to normal. In addition, 20 cases of APRT deficiency in renal transplant recipients were also reviewed. We hope this case increases awareness of APRT deficiency in repeated obstructive nephropathy post-transplantation, which is a treatable disease for which the misdiagnosis or delayed diagnosis should be avoided.

Automated summary

This case report highlights a kidney transplant patient who experienced recurrent obstructive nephropathy post-transplantation, later identified by gene testing as having APRT deficiency. Treatment with allopurinol resulted in progressive improvement of allograft function. Additionally, 20 cases of APRT deficiency in renal transplant recipients were reviewed, emphasizing the importance of early recognition and treatment to avoid misdiagnosis or delayed diagnosis.