Primary hyperoxaluria type II and organ transplantation / 器官移植

Primary hyperoxaluria type Ⅱ (PH2) is an inherited disorder of the glyoxylate metabolism caused by the gene mutation of glyoxylate reductase/hydroxypyruvate reductase (GRHPR). PH2 is characterized by recurrent nephrolithiasis and nephrocalcinosis, which may even progress into end-stage renal disease. Currently, organ transplantation is the only treatment option for PH2, which mainly includes two strategies: kidney transplantation and combined liver and kidney transplantation. Kidney transplantation yields a high risk of recurrence of oxalate nephropathy, which may cause early graft dysfunction. Combined liver and kidney transplantation could mitigate the deficiency of oxalate metabolism, whereas it yields a high risk of graft complications. PH2 is an extremely rare disorder. No consensus has been reached on the indications, surgical selection and perioperative management of organ transplantation for PH2 patients. In this article, the pathogenesis, diagnosis, monitoring and organ transplantation experience of PH2 were reviewed, aiming to divert clinicians' attention to PH2 and provide reference for determining diagnosis and treatment regimens, especially transplantation strategy for PH2 patients.

Summary of clinical characteristics, diagnosis and treatment of primary hyperoxaluria type 1 in mainland China / 器官移植

Objective To investigate the clinical manifestations, treatment and prognosis of primary hyperoxaluria type 1 (PH1). Methods Relevant literature review was conducted from Chongqing VIP, CNKI, Wanfang Data, PubMed, Web of Science, Embase and Cochrane databases. Clinical data of 57 patients with PH1 were collected, and the clinical manifestations, diagnosis and treatment and prognosis were analyzed. Results A total of 35 eligible studies were searched, including 57 patients with PH1, 39 male and 18 female, aged 0.2-57.0 years old, and the age of onset was from date of birth to 42 years old. The specificity of clinical symptoms of 57 patients with PH1 was relatively low, including 41 cases of renal stones, 21 cases of renal calcification and/or calcium deposition, 12 cases of oxalic acid deposition outside the urinary system, 12 cases of lumbago, backache and abdominal pain, and 8 cases of ureteral stones. Besides, alternative symptoms, such as decreased urine output, metabolic acidosis, disorder of water and electrolyte, anemia and gross hematuria were also reported. Thirty-three patients were diagnosed with end-stage renal disease (ESRD) upon admission. Twenty-six patients received transplantation. Among them, 17 cases underwent kidney transplantation (2 cases repeatedly received combined liver-kidney transplantation due to recurrence of stones and resumption of dialysis, and 1 case repeatedly received liver transplantation due to resumption of dialysis), 7 cases received combined liver-kidney transplantation, 2 cases underwent liver transplantation, and 3 cases received sequential liver-kidney transplantation, respectively. Thirty-one patients did not undergo transplantation. Significant differences were observed in the survival rate between patients treated with and without transplantation (85% vs. 58%, P < 0.05). Conclusions Clinical manifestations of PH1 are diverse and lack of specificity. A majority of PH1 patients are diagnosed with ESRD upon admission. Clinical prognosis of patients undergoing transplantation is better than that of those counterparts without transplantation. Prior liver transplantation or combined liver-kidney transplantation is recommended.

Multi-disciplinary team on renal allograft dysfunction induced by recurrence of primary hyperoxaluria type I after renal transplantation / 器官移植

Objective To investigate the clinical characteristics and the experience of multi-disciplinary team (MDT) on recurrence of primary hyperoxaluria (PH) type I after renal transplantation. Methods One case presenting with unexplained rapid decline of renal allograft function after allogeneic renal transplantation was discussed by MDT. The role of MDT in diagnosing rare hereditary diseases and improving the long-term survival of renal transplant recipients was summarized. Results After MDT consultation, the patient was diagnosed with recurrence of PH type I. Routine immunosuppressive regimen was initiated after the exclusion of rejection. The patient was instructed to drink a large quantity of water, and given with high-quality protein and low-phosphorus diet, vitamin B6, calcium and other conservative therapies to actively prevent and treat postoperative complications. The deterioration of renal graft function was delayed. Nevertheless, regular hemodialysis was resumed at 5 months after renal transplantation until the submission date of this manuscript. Conclusions Recurrence of PH type I after renal transplantation is relatively rare. The main clinical manifestations are recurrent kidney stones and decreased renal function with multiple complications and poor prognosis. The condition of the patient is consulted by MDT for confirming the diagnosis, determining the optimal treatment scheme, delaying the progression and improving the clinical prognosis.

Primary Hyperoxaluria in Korean Pediatric Patients

BACKGROUND: Primary hyperoxaluria (PH), a rare inborn error of glyoxylate meta bolism causing overproduction of oxalate, is classified into three genetic subgroups: type 1–3 (PH1–PH3) caused by AGXT, GRHPR , and HOGA1 gene mutations, respectively. We performed a retrospective case series study of Korean pediatric patients with PH.METHODS: In total, 11 unrelated pediatric patients were recruited and their phenotypes and genotypes were analyzed by a retrospective review of their medical records.RESULTS: Mutational analyses revealed biallelic AGXT mutations (PH1) in nine patients and a single heterozygous GRHPR and HOGA1 mutation in one patient each. The c.33dupC was the most common AGXT mutation with an allelic frequency of 44%. The median age of onset was 3 months (range, 2 months-3 years), and eight patients with PH1 presented with end stage renal disease (ESRD). Patients with two truncating mutations showed an earlier age of onset and more frequent retinal involvement than patients with one truncating mutation. Among eight PH1 patients presenting with ESRD, five patients were treated with intensive dialysis followed by liver transplantation (n=5) with/without subsequent kidney transplantation (n=3).CONCLUSION: Most patients presented with severe infantile forms of PH. Patients with two truncating mutations displayed more severe phenotypes than those of patients with one truncating mutation. Sequential liver and kidney transplantation was adopted for PH1 patients presenting with ESRD. A larger nation-wide multicenter study is needed to confirm the genotype-phenotype correlations and outcomes of organ transplantation.

Determination of oxalate in human plasma and urine by RP-HPLC / 中草药

Objective: To establish a method of reversal phase-high performance liquid chromatography (RP-HPLC) for determining the mass concentration of oxalate in human plasma and urine and to monitor the variation of mass concentration of oxalate in the patients with primary hyperoxaluria (PH) before and after combined liver-kidney transplantation. Methods: Agilent XDBC18 (150 mm × 4.6 mm, 5 μm) column and Agilent Zorbax extend-C18 (12.5 mm × 4.6 mm, 5 μm) guard column were used. Methyl alcohol and aqueous solution containing 0.1 mol/L ammoniom acetate (15∶85) were used as mobile phase. The flow rate was at 1.2 mL/min, ultraviolent determination wavelength was 314 nm, column temperature was at 26.3 ℃, and injection volume was 50 μL. o-phenylenediamine was used as derivating agent, reacted with oxalate in human plasma and urine so as to obtain the compound with better ultraviolet absorption-2, 3-dyhydroxy quinoxaline. Results: The detection limit in human plasma was 0.3 mg/L, the linear range was 1.953-125 mg/L, the average recovery was 94.89%, and its RSD was 4.1%; The detection limit in urine was 0.5 mg/L, the linear range was 1.953-125 mg/L, the average recovery was 94.31%, and its RSD was 3.2%. Conclusion: The method is believable for determining the mass concentration of oxalate with its simplicity, sensibility, repeatability, and better recovery rate.

A Case of Primary Hyperoxaluria with Renal Allograft Dysfunction / 대한신장학회지

Primary hyperoxaluria is a rare disorder of glyoxylate metabolism in which hepatic enzyme deficiencies result in overproduction of oxalate. The resulting elevation of urinary oxalate excretion leads to recurrent urolithiasis and progressive nephrocalcinosis. End-stage renal disease frequently occurs and is accompanied by systemic oxalate deposition along with its harmful effects. With the rarity and various clinical heterogeneity of the disease, the high proportion of patients in whom diagnosis is made after advanced renal failure have developed it. On account of its high rate of graft loss associated with primary hyperoxaluria, isolated kidney transplantation has been replaced by combined liver/kidney transplantation. In this report, we describe a case of primary hyperoxaluria with kidney graft failure who had a history of recurrent renal stones.

End-stage Renal Disease Caused by Primary Hyperoxaluria / 대한신장학회잡지

Primary hyperoxaluria is a rare autosomal recessive inherited metabolic disease which results from endogenous overproduction of oxalic acid. It causes variant phenotypes from renal failure in infancy to mere urolithiasis in late adulthood. We report a case of primary hyperoxaluria in a 11-year-old boy. He presented with recurrent multiple renal stones since 3 years of age. He had renal failure and markedly increased hyperoxaluria (568.26 microgram/mg of creatinine (normal: 0.04-0.15)) and his stones consisted of a mixture of calcium oxalate (30%) and calcium phosphate (10%) in contrast to pure calcium oxalate monohydrate in the other primary hyperoxaluria type 1 patients. A renal biopsy showed interstitial cellular infiltration with crystals which are birefringent under polarized light within the tubules. His general conditions were improved after hemodialysis treatment. For definite cure of disease, combined liver-kidney transplantation is considered.

Primary hyperoxaluria: Cases report.

Primary hyperoxaluria is a rare disease characterized by recurrent calcium oxalate nephrolithiasis and nephrocalcinosis. The most diagnostic laboratory finding if an increased amount of urinary oxalate. The inheritance is presumed to be autosomal recessive but autosomal dominant has been repoeted. Here are reported cases of a family: a boy, his brother, and his father. The boy, the most severely affected died at the age of 8 years. His 6-year-old brother, treated by 6 episodes of Extracorporeal Piezo Electric Lithotripsy (EPL); followed with high doses of pyridoxine and thiazides orally, is still alive with normal renal function. His father was treated by 6 episodes of EPI but without medication. The authors suggest that investigations for metabolic causes should be done in children with positive family history of nephrolithiasis.