Blog
About

16
views
0
recommends
+1 Recommend
1 collections
    0
    shares
      • Record: found
      • Abstract: found
      • Article: found

      International Registry for Primary Hyperoxaluria

      Read this article at

      ScienceOpenPublisherPubMed
      Bookmark
          There is no author summary for this article yet. Authors can add summaries to their articles on ScienceOpen to make them more accessible to a non-specialist audience.

          Abstract

          Background/Aims: Primary hyperoxaluria (PH) is an inherited disorder that causes calcium urolithiasis and renal failure. Due to its rarity, experience at most centers with this disease is limited. Methods: A secure, web-based, institutional review board/ethics committee and American Health Insurance Portability and Accountability Act (HIPAA)-compliant registry was developed to facilitate international contributions to a data base. To date 95 PH patients have been entered. Results: PH type was confirmed in 84/95 (PH1 79%, PH2 9%). Mean age ± SD at symptom onset was 9.5 ± 10.2 (median 5.5) years whereas age at diagnosis was 15.0 ± 15.2 (median 10.0) years. Urolithiasis was present at diagnosis in 90% (mean 7, median 1, stones prior to diagnosis) and nephrocalcinosis in 48%. Surprisingly 15% of the patients were asymptomatic at the time of diagnosis. Nineteen of the 95 patients were first recognized to have PH after they had reached end-stage renal disease, with the diagnosis made only after kidney transplantation in 7 patients. Patients were followed for 12.1 ± 10.6 (median 9.4) years. Thirty-four of 95 progressed to end-stage renal failure, before (19 patients) or after (15 patients) diagnosis. In the PH1 cohort actuarial renal survival was 64% at 30 years of age, 47% at 40 years, and 29% at 50 years. Conclusion: We have developed a PH registry, and demonstrated the feasibility of this secure, web-based approach for data entry. By facilitating accumulation of an increasing cohort of patients, this registry should allow more complete characterization of clinical expression of PH, an appreciation of geographic variability, and identification of treatment outcomes.

          Related collections

          Most cited references 7

          • Record: found
          • Abstract: found
          • Article: not found

          A United States survey on diagnosis, treatment, and outcome of primary hyperoxaluria.

          Primary hyperoxaluria (PH) is a heterogeneous disease with a variable age of onset and a variable progression into kidney failure. Early diagnosis is mandatory to avoid the damaging effects of systemic calcium oxalate deposition. In 1997, we initiated a nationwide survey of American nephrologists to ascertain epidemiological data and current practices. PH was reported in only 102 patients, with PH I in 79 and PH II in 9; 14 patients were not classified. Most patients were Caucasian (84%). Main symptoms at diagnosis were urolithiasis (54.4%) and nephrocalcinosis (30%). A significant delay of diagnosis was seen in 42% of patients and 30% of patients were diagnosed only at end-stage renal disease (ESRD). Diagnosis was usually based on history and urinary oxalate excretion. Glycolate and l-glyceric acid excretion were rarely determined. To determine the enzyme defect, a liver biopsy was performed in 40%. Even at ESRD, only 56% of patients received an adequate diagnostic work-up. Half of the patients showed 'good' or 'fair' pyridoxine sensitivity. In addition to B(6), most patients received either citrate or orthophosphate. Kidney transplantation (KTx) failed in 19 of 32 transplants ( n=27 patients) and was due to recurrent oxalosis in 8 transplants. Liver Tx was performed after KTx in 5 patients (1 patient died). Combined liver-kidney Tx in 21 patients (in 9 patients after failure of KTx) achieved good organ function in 13 patients; 7 patients, however, died shortly after transplantation. In conclusion, the time between first symptom and diagnosis of PH must be minimized, and the diagnostic procedures have to be improved. The cases of unclassified hyperoxaluria suggest the possibility of additional type(s) of PH. As isolated KTx failed in 59% of patients, combined liver-kidney Tx seems to be the better choice in place of isolated KTx as the primary transplant procedure.
            Bookmark
            • Record: found
            • Abstract: found
            • Article: not found

            Results of long-term treatment with orthophosphate and pyridoxine in patients with primary hyperoxaluria.

            The prognosis for patients with primary hyperoxaluria has been ominous, with the expectation of renal failure, poor results with transplantation, and early death. We studied the long-term effects of orthophosphate and pyridoxine therapy in 25 patients with primary hyperoxaluria who were treated for an average of 10 years (range, 0.3 to 26). Their mean age at the start of treatment was 12 years (median, 6; range, 0.5 to 32). We also studied the effect of orthophosphate and pyridoxine on urinary supersaturation with calcium oxalate, crystal inhibition using a seeded growth system, and crystal formation using scanning electron microscopy in 12 patients during three-day stays in the clinical research center. The mean (+/- SD) glomerular filtration rate at the start of treatment was 91 +/- 26 ml per minute per 1.73 m2. The median decline in glomerular filtration rates was 1.4 ml per minute per 1.73 m2 of body-surface area per year. The actuarial survival free of end-stage renal disease was 96, 89, 74, and 74 percent of 5, 10, 15, and 20 years, respectively. Treatment with orthophosphate and pyridoxine reduced urinary supersaturation with calcium oxalate from 8.3 +/- 3.0 to 2.1 +/- 1.7 kJ per mole at 38 degrees C (P < 0.001), increased the inhibition of calcium oxalate formation from 63 +/- 11 to 108 +/- 10 inhibitor units per 24 hours (P < 0.001), and improved the crystalluria score from 2.6 +/- 0.3 to 0.6 +/- 0.1 (P < 0.001). Treatment of patients with primary hyperoxaluria with orthophosphate and pyridoxine decreases urinary calcium oxalate crystallization and appears to preserve renal function.
              Bookmark
              • Record: found
              • Abstract: found
              • Article: not found

              Combined liver-kidney transplantation in primary hyperoxaluria type 1.

              Primary hyperoxaluria type 1 (PH1) is a rare autosomal recessive disorder characterised by an increased urinary excretion of calcium oxalate, leading to recurrent urolithiasis, nephrocalcinosis and accumulation of insoluble oxalate throughout the body (oxalosis) when the glomerular filtration rate falls to below 40-20 mL/min per 1.73 m(2). The disease is due to a functional defect of the liver-specific peroxisomal enzyme alanine: glyoxylate aminotransferase (AGT), the gene of which is located on chromosome 2q37.3. The diagnosis is based on increased urinary oxalate and glycollate, increased plasma oxalate and AGT measurement in a liver biopsy. AGT mistargeting may be investigated by immuno-electron microscopy and DNA analysis. End-stage renal failure is reached by the age of 15 years in 50% of PH1 patients and the overall death rate approximates 30%. The conservative treatment includes high fluid intake, pyridoxine and crystallisation inhibitors. Since the kidney is the main target of the disease, isolated kidney transplantation (Tx) has been proposed in association with vigorous peri-operative haemodialysis in an attempt to clear plasma oxalate at the time of Tx. However, because of a 100% recurrence rate, the average 3-year graft survival is 15%-25% in Europe, with a 5-10-year patient survival rate ranging from 10% to 50%. Since the liver is the only organ responsible for the detoxification of glyoxylate by AGT, deficient host liver removal is the first rationale for enzyme replacement therapy. Subsequent orthotopic liver Tx aims to supply the missing enzyme in its normal cellular and subcellular location and thus can be regarded as a form of gene therapy. Because of the usual spectrum of the disease, isolated liver Tx is limited to selected patients prior to having reached an advanced stage of chronic renal failure. Combined liver-kidney Tx has therefore become a conventional treatment for most PH1 patients: according to the European experience, patient survival approximates 80% at 5 years and 70% at 10 years. In addition, the renal function of survivors remains stable over time, between 40 and 60 mL/min per 1.73 m(2) after 5 to 10 years. In addition, liver Tx may allow the reversal of systemic storage disease (i.e. bone, heart, vessels, nerves) and provide valuable quality of life. Whatever the transplant strategy, the outcome is improved when patients are transplanted early in order to limit systemic oxalosis. According to the European experience, it appears that combined liver-kidney Tx is performed in PH1 patients with encouraging results, renal Tx alone has little role in the treatment of this disease, and liver Tx reverses the underlying metabolic defect and its clinical consequences.
                Bookmark

                Author and article information

                Journal
                AJN
                Am J Nephrol
                10.1159/issn.0250-8095
                American Journal of Nephrology
                S. Karger AG
                0250-8095
                1421-9670
                2005
                June 2005
                01 July 2005
                : 25
                : 3
                : 290-296
                Affiliations
                Departments of aInternal Medicine and bPediatrics, cDivision of Nephrology and Hypertension, dDepartment of Health Sciences Research, Division of Biostatistics, and eMayo Clinic Hyperoxaluria Center, Mayo Clinic College of Medicine, Rochester, Minn., USA
                Article
                86360 Am J Nephrol 2005;25:290–296
                10.1159/000086360
                15961949
                © 2005 S. Karger AG, Basel

                Copyright: All rights reserved. No part of this publication may be translated into other languages, reproduced or utilized in any form or by any means, electronic or mechanical, including photocopying, recording, microcopying, or by any information storage and retrieval system, without permission in writing from the publisher. Drug Dosage: The authors and the publisher have exerted every effort to ensure that drug selection and dosage set forth in this text are in accord with current recommendations and practice at the time of publication. However, in view of ongoing research, changes in government regulations, and the constant flow of information relating to drug therapy and drug reactions, the reader is urged to check the package insert for each drug for any changes in indications and dosage and for added warnings and precautions. This is particularly important when the recommended agent is a new and/or infrequently employed drug. Disclaimer: The statements, opinions and data contained in this publication are solely those of the individual authors and contributors and not of the publishers and the editor(s). The appearance of advertisements or/and product references in the publication is not a warranty, endorsement, or approval of the products or services advertised or of their effectiveness, quality or safety. The publisher and the editor(s) disclaim responsibility for any injury to persons or property resulting from any ideas, methods, instructions or products referred to in the content or advertisements.

                Page count
                Figures: 4, Tables: 3, References: 12, Pages: 7
                Product
                Self URI (application/pdf): https://www.karger.com/Article/Pdf/86360
                Categories
                7th International Workshop on Primary Hyperoxaluria. October, 2004, Rochester, Minn. ...

                Cardiovascular Medicine, Nephrology

                Oxalosis, Oxalate, Nephrocalcinosis, Calcium oxalate, Nephrolithiasis

                Comments

                Comment on this article