1/99. diagnosis and management of primary hyperoxaluria type 1 in infancy. We report a case of a 6-month-old infant who presented with failure to thrive due to end-stage renal disease as a result of primary hyperoxaluria type 1. The infant was managed with a combined daily hemodialysis and peritoneal dialysis prescription in order to manage the total body oxalate burden. Medical management included oral pyridoxine, aggressive hydration and nutritional supplementation via an enteral feeding tube. At one year of age the infant underwent a combined liver/kidney transplantation with intra- and daily post-operative hemodialysis to prevent oxalate deposition in the newly transplanted organs. The post-operative course was complicated by gross hematuria and increased hyperoxaluria, requiring an increase in hydration and thiazide diuretics. This infant received a combination of dialysis modalities which was designed to lower the potential oxalate burden prior to transplantation. This case illustrates the difficulty in medical management of an infant pre- and post-combined liver/kidney transplantation. ( info) |
2/99. Oxalate kinetics and reversal of the complications after orthotopic liver transplantation in a patient with primary hyperoxalosis type 1 awaiting renal transplantation. We present the case of a young woman with end-stage renal disease secondary to primary hyperoxaluria type 1, who after 3 years and 6 months of maintenance hemodialysis, and despite intensification of the dialytic treatment, developed severe livedo reticularis in her extremities leading to ischemic cutaneous ulcerations, necessitating continuous intravenous infusion of narcotics for pain control. She received a liver transplant after native hepatectomy. However, due to positive crossmatch, she could not receive a kidney from that donor. After transplantation, following serial serum oxalate levels, the hemodialysis regimen was safely reduced from 4 h daily to 3 h three times weekly. Over the course of 6 weeks after liver transplantation, her livedo reticularis resolved, the ischemic ulcers markedly improved, she was weaned off all pain medications, and her erythropoietin-resistant anemia resolved. Our results suggest that in patients with primary hyperoxaluria type 1, who have received a liver transplant and are on maintenance hemodialysis, after serial serum oxalate determinations, some may safely be changed to a thrice-weekly maintenance hemodialysis regimen. Moreover, with this regimen the complications of systemic oxalosis can reverse. ( info) |
3/99. Primary hyperoxaluria 1: catch up growth and normalization of oxaluria 6 years after hepatorenal transplantation in a prepubertal boy. We present data on urinary oxalate (U(OX)), renal function, growth and bone age in a 10-year-old male with primary hyperoxaluria type 1. The patient had undergone combined liver-kidney transplantation at the age of 4.5 years. UOX increased up to 10(4) micromol/24 h after transplantation and declined to normal values thereafter. Excessive Uox concentrations after surgery might have been due to a bone pool of unsoluble oxalate and declined spontaneously. creatinine clearance remained stable during observation period. The boy showed significant catch up growth. Height standard deviation score for chronological age improved from -2.4 before transplantation to -0.3 after 6 years. Radiological bone density improved at the same time. Hepatorenal transplantation should be performed in children with primary hyperoxaluria 1 before end-stage renal failure to normalize oxalate excretion and improve growth and bone mineralization. ( info) |
| We describe 4 patients, aged 3 months to 23 years, with end-stage renal disease and severe, symptomatic hypothyroidism. All 4 had primary hyperoxaluria type 1 (PH1) with diffuse tissue (kidneys, skeleton, eyes, heart) calcium-oxalate deposition, a condition known as oxalosis. The hypothyroidism responded to thyroid hormone replacement therapy. Clinical hypothyroidism within the framework of PH1/oxalosis was probably caused by thyroid tissue damage from an abundance of calcium oxalate. We recommend that thyroid function be monitored in patients with PH1 and oxalosis. ( info) |
5/99. Partial deletion of the AGXT gene (EX1_EX7del): A new genotype in hyperoxaluria type 1. Primary hyperoxaluria type 1 (PH1) is a rare autosomal (2q37.3) recessive metabolic disease caused by a deficiency of the hepatic peroxisomal enzyme alanine:glyoxylate amino transferase. Molecular heterogeneity is important in PH1 as most of the patients (if the parents are unrelated) are compound heterozygotes for rare mutations. We describe the first large deletion in the AGXT gene, removing exons 1 to 7 (EX1_EX7del) that was responsible for one case of severe PH1. This 10 kb deletion was identified by Southern blotting of genomic dna digested by Xba I and hybridized with different exonic probes. Both parents (from turkey) are first cousin and carry the deletion. It is of note that the presently reported patient did not exhibit any AGT catalytic activity and even so, he progressed towards end-stage renal disease only at 19 years old. ( info) |
6/99. Liver-kidney-transplantation in type 1 primary hyperoxaluria: description and comments on a case. BACKGROUND: Primary hyperoxaluria leads to oxalosis, a systemic illness with fatal prognosis in uremic youngsters because of systemic complications. Case report: A 14-year old boy with primary type 1 hyperoxaluria who had a long-lasting history of nephrolithiasis and passed from normal renal function to end-stage renal disease within 7 months. MEASUREMENT of alanine: glyoxylate aminotransferase (AGT) catalytic activity in the liver biopsy disclosed very low activity which was not. responsive to pyridoxin., thus the patient entered onto a priority national waiting list for liver-kidney transplantation and a week later received a combined transplant. In order to increase body clearance of oxalate, the patient underwent medical treatment to increase urine oxalate solubility (sodium and potassium citrate oral therapy, magnesium supplementation and increase of diuresis) and intensive dialysis both before and after transplantation. comment: The medical approach to the treatment of this rare illness is discussed. Since the major risk for the grafted kidney is related to the oxalate burden, i.e. oxalate deposition from the body deposits to the kidney that becomes irreversibly damaged, treatment consists of increasing the body clearance of oxalate both by increasing oxalate solubility in the urine and with intensive dialysis performed both before and after combined transplantation. To the same extent (by limiting body oxalate deposits), a relatively early (native GFR 20-25 ml/minute) transplantation is advisable. ( info) |
7/99. Dilemma of oxalosis in end stage renal failure: isolated kidney allograft or hemodialysis. We report the case of a 10-year-old girl who received a cadaveric kidney transplant for oxalosis after a period of 12 months on hemodialysis. The donor was a 6-year-old child. cold ischemia was four hours. diuresis occurred immediately in the operating room. Mean daily diuresis was maintained at 8 liters: first by i.v. perfusion, then by nocturnal continuous nasogastric hydration. In addition to the usual immunosuppressive drugs, she received pyridoxine, sodium citrate, phosphate, hydrochlorothiazide and magnesium. Daily hemodialysis was performed from Day 1 to Day 9 and four additional sessions every other day. The postoperative course was satisfactory. Oxaluria was elevated initially at 1074 mg/24 h (normal < 50 mg/24 h). One year later, mean daily diuresis is still 8 liters, renal function is normal and oxaluria is at 296 mg/24 h. Repeated graft sonography showed no nephrocalcinosis, but mild oxalate deposits are noted on renal biopsy. Isolated renal transplantation was successful in our patient. It allowed us to stop hemodialysis and to avoid extra-renal accumulation of oxalate. Despite this success, we are convinced that long term prognosis is uncertain and liver transplantation should be realized to correct definitely the biochemical defect. ( info) |
8/99. Improved growth velocity with intensive dialysis. Consequence or coincidence? growth failure in children with end-stage renal disease remains a difficult problem. A 2.5-month-old baby in renal failure due to primary hyperoxaluria type I received intensive dialysis aimed at decreasing oxalate tissue accretion. Over 5.5 months, while awaiting transplantation, his growth velocity was 29 cm/year compared with an average 4 cm/year in infants on hemodialysis and 22 cm/year in normal infants of this age. This remarkable growth rate, which could have represented catch-up growth, is hypothesized to be related to the delivered dialysis dose. It is suggested that this relationship be evaluated in a prospective randomized trial. ( info) |
9/99. Small intestinal infarction: a fatal complication of systemic oxalosis. Primary hyperoxaluria is a rare genetic disorder characterised by calcium oxalate nephrolithiasis and nephrocalcinosis leading to renal failure, often with extra-renal oxalate deposition (systemic oxalosis). Although ischaemic complications of crystal deposition in vessel walls are well recognised clinically, these usually take the form of peripheral limb or cutaneous ischaemia. This paper documents the first reported case of fatal intestinal infarction in a 49 year old woman with systemic oxalosis and advocates its consideration in the differential diagnosis of an acute abdomen in such patients. ( info) |
10/99. Primary hyperoxaluria type 1 causing end-stage renal disease in a 45-year-old patient. Primary hyperoxaluria type 1 (PH1) is caused by deficiency of peroxisomal alanine-glyoxylate aminotransferase which is in humans exclusively expressed in liver cells. The disease is inherited as an autosomal recessive trait, and initial symptoms usually occur in early childhood. Up to the age of 25 years, 90% of the patients are symptomatic, and many patients develop end-stage renal failure. Pronounced medical care is necessary in PH1 patients to prevent generalized oxalosis with complications due to bone disease and peripheral gangrene. The rather short survival of patients on hemodialysis is caused by sudden arrhythmias and heart block. As no dialysis procedure is able to remove the daily produced oxalate, early transplantation is mandatory. Our 45-year-old patient is remarkable on the basis of the late manifestations of PH1. The diagnosis was delayed by unspecific symptoms of nephrolithiasis with recurrent pyelonephritis. Clinical course and diagnostic cornerstones of primary hyperoxaluria are outlined. The principles of conservative treatment and experiences with dialysis and transplantation are discussed. ( info) |