2,8-Dihydroxyadenine Nephropathy Identified as Cause of End-Stage Renal Disease After Renal Transplant (original) (raw)

Adenine Phosphoribosyltransferase Deficiency as a Rare Cause of Renal Allograft Dysfunction

Journal of the American Society of Nephrology, 2014

Adenine phosphoribosyltransferase deficiency is a rare autosomal recessive disorder manifesting as urolithiasis or crystalline nephropathy. It leads to the generation of large amounts of poorly soluble 2,8-dihydroxyadenine excreted in urine, yielding kidney injury and in some patients, kidney failure. Early recognition of the disease, institution of xanthine analog therapy to block the formation of 2,8dihydroxyadenine, high fluid intake, and low purine diet prevent CKD. Because of symptom variability and lack of awareness, however, the diagnosis is sometimes extremely deferred. We describe a patient with adenine phosphoribosyltransferase deficiency who was diagnosed during evaluation of a poorly functioning second kidney allograft. This report highlights the risk of renal allograft loss in patients with undiagnosed adenine phosphoribosyltransferase deficiency and the need for improved early detection of this disease.

Decreased Kidney Function and Crystal Deposition in the Tubules After Kidney Transplant

American Journal of Kidney Diseases, 2010

Adenine phosphoribosyltransferase (APRT) deficiency is an autosomal recessive purine enzyme defect that results in the inability to utilize adenine, which consequently is oxidized by xanthine dehydrogenase to 2,8-dihydroxyadenine (2,8-DHA), an extremely insoluble substance eventually leading to crystalluria, nephrolithiasis, and kidney injury. We describe a case of APRT deficiency not diagnosed until the evaluation of a poorly functioning kidney transplant in a 67-year-old white woman. After the transplant, there was delayed transplant function, urine specimens showed crystals with unusual appearance, and the transplant biopsy specimen showed intratubular obstruction by crystals identified as 2,8-DHA using infrared spectroscopy. APRT enzymatic activity was undetectable in red blood cell lysates, and analysis of the APRT gene showed 1 heterozygous sequence variant, a duplication of T at position 1832. The patient was treated with allopurinol, 300 mg/d, and transplant function progressively normalized. Because patients with undiagnosed APRT deficiency who undergo kidney transplant may risk losing the transplant because of an otherwise treatable disease, increased physician awareness may hasten the diagnosis and limit the morbidity associated with this disease. Am J Kidney Dis xx:xxx.

Adenine phosphoribosyltransferase (APRT) deficiency: a new genetic mutation with early recurrent renal stone disease in kidney transplantation

NDT Plus, 2010

Adenine phosphoribosyltransferase (APRT) deficiency, a rare inborn error inherited as an autosomic recessive trait, presents with 2,8-dihydroxyadenine (2,8-DHA) crystal nephropathy. We describe clinical, biochemical and molecular findings in a renal transplant recipient with renal failure, 2,8-DHA stones and no measurable erythrocyte APRT activity. Homozygous C>G substitution at −3 in the splicing site of exon 2 (IVS2 −3 c>g) was found in the APRT gene. The patient's asymptomatic brother was heterozygous for such mutation, and his APRT activity was 23% of controls. A splicing alteration leading to incorrect gene transcription and virtually absent APRT activity is seemingly associated with the newly identified mutation.

Crystalline nephropathy due to adenine phosphoribosyl transferase deficiency as a cause of renal allograft dysfunction

Archives of Clinical Nephrology, 2020

A 22-year-old male born of non-consanguineous marriage, End stage renal failure on dialysis presented with the history Key message APRT defi ciency is a rare but under recognized genetic disease. Recurrent urolithiasis and DHA nephropathy are the two clinical manifestations of APRT defi ciency and diagnosis can be made at any age and recurs after renal transplant. Allopurinol is the cornerstone in preventing recurrence. APRT activity assay and genetic testing are useful for confi rmation of diagnosis, for family screening and in diffi cult cases of urolithias or crystalline nephropathy.

Crystalline nephropathy due to 2,8-dihydroxyadeninuria: an under-recognized cause of irreversible renal failure

Nephrology Dialysis Transplantation, 2010

Background. 2,8-dihydroxyadeninuria (DHA) disease (also called 2,8 dihydroxyadeninuria) is a rare autosomal recessive disorder caused by complete adenine phosphoribosyltransferase def iciency and typically manifests as recurrent nephrolithiasis. Only rare cases of DHA nephrolithiasis have been reported from the USA. Herein, we report three American patients who developed DHA crystalline nephropathy leading to end-stage renal disease (ESRD) with recurrence in the allograft. Methods. Three cases of DHA crystalline nephropathy were identified from the Renal Pathology Laboratory of Mayo Clinic. Detailed clinical and pathologic descriptions are provided. Results. All three patients were Caucasian adults with no history of obstructive nephropathy. Two patients had no history of nephrolithiasis and one had a single episode of stones 36 years prior to presentation. All patients presented with severe renal failure with a mean serum creatinine of 7.5 mg/dl. Renal biopsies revealed numerous tubular and interstitial brown DHA crystals, tubular degenerative changes and moderate to marked tubulointerstitial scarring. Two patients were initially misdiagnosed, one as primary hyperoxaluria and the other as chronic interstitial nephritis. All three patients progressed to ESRD, within 1 month following renal biopsy in two and after 9 months in one. All three patients underwent renal transplantation with early disease recurrence in three allografts in two patients. Conclusions. DHA disease is an under-recognized condition that can lead to irreversible renal failure and frequently recurs in the transplant. It should be included in the differential diagnosis of crystalline nephropathy, even in the absence of history of nephrolithiasis.

Adenine Phosphoribosyltransferase Deficiency: A Rare Cause of Recurrent Urolithiasis

Journal of endourology case reports, 2017

Background: Recurrent urolithiasis is troublesome for both patient and clinician, and in most cases, an underlying cause is not found. An important and underdiagnosed cause is adenine phosphoribosyltransferase (APRT) deficiency that gives rise to 2,8-dihydroxyadenine (2,8-DHA) stones. If diagnosed early, patient morbidity as well as the financial cost of treating stone recurrence can be avoided with simple medical therapy. Case Presentation: A 36-year-old white, Caucasian male with recurrent urolithiasis was found to have 2,8-DHA stones. This was difficult to manage, as these stones were often large, bilateral, matrix in structure, and translucent on plain X-rays. He underwent a multitude of interventions including both retrograde and anterograde endoscopic approaches as well as extracorporeal shock wave lithotripsy. The specific stone type was eventually discovered through infrared spectroscopy and he was promptly commenced on allopurinol, which significantly improved his stone bur...

Quantitative UPLC-MS/MS assay of urinary 2,8-dihydroxyadenine for diagnosis and management of adenine phosphoribosyltransferase deficiency

Journal of chromatography. B, Analytical technologies in the biomedical and life sciences, 2016

Adenine phosphoribosyltransferase (APRT) deficiency is a hereditary disorder that leads to excessive urinary excretion of 2,8-dihydroxyadenine (DHA), causing nephrolithiasis and chronic kidney disease. Treatment with allopurinol or febuxostat reduces DHA production and attenuates the renal manifestations. Assessment of DHA crystalluria by urine microscopy is used for therapeutic monitoring, but lacks sensitivity. We report a high-throughput assay based on ultra-performance liquid chromatography coupled to tandem mass spectrometry (UPLC-MS/MS) for quantification of urinary DHA. The UPLC-MS/MS assay was optimized by a chemometric approach for absolute quantification of DHA, utilizing isotopically labeled DHA as an internal standard. Experimental screening was conducted with D-optimal design and optimization of the DHA response was performed with central composite face design and related to the peak area of DHA using partial least square regression. Acceptable precision and accuracy of...

Adenine phosphoribosyltransferase deficiency and renal allograft dysfunction

American Journal of Kidney Diseases, 2001

• Adenine phosphoribosyltransferase (APRT) deficiency is a rarely diagnosed cause of renal allograft dysfunction. We report the case of a 42-year-old man who presented in 1996 with idiopathic renal failure. Native kidney biopsy showed extensive microcrystalline interstitial nephritis. The patient subsequently underwent a living-related kidney transplant with excellent early graft function. During the next year, however, he had worsening allograft function, and allograft biopsy showed recurrent interstitial nephritis. Further chemical and spectroscopic analysis showed this lesion to be an annular microcrystalline nephritis consistent with APRT deficiency. This diagnosis was confirmed on erythrocyte assay. Treatment with allopurinol and a low-purine diet led to improvement and stabilization of renal function. APRT is a rare cause of renal allograft dysfunction requiring a high index of suspicion for early diagnosis and treatment. Increased physician awareness in the United States may hasten diagnosis and limit the morbidity associated with this disease.