Search

Background Kidney transplantation in children in 1970 was considered by many to be unethical, as long-term survival was minimal. It was therefore risky at the time to offer transplantation to a child. Case diagnosis/treatment A 6-year-old boy with kidney failure due to haemolytic uraemic syndrome received 4 months of intermittent peritoneal dialysis followed by 6 months of haemodialysis until at 6 years and 10 months, he underwent bilateral nephrectomy and received a kidney transplant from a deceased 18-year-old donor. Despite moderate long-term immunosuppression of prednisone (20 mg/48 h) and azathioprine (62.5 mg/day), at the last visit in September 2022, he was well, normotrophic, with a serum creatinine of 157 µmol/l (eGFR 41 ml/min/1.73 m2) and no haematuria, proteinuria or hypertension. Except for benign skin lesions due to azathioprine, and undergoing an aortic valve replacement and an aortic aneurysm repair in adulthood, the now 58-year-old man has had no major complications. Conclusions We speculate that stable and unmodified immunosuppressive therapy, started before the era of calcineurin inhibitors, the lack of significant rejection episodes, the absence of donor-specific antibodies, and the young donor age have contributed to maintaining exceptional long-term kidney transplant survival. Luck, a robust health system and an adherent patient are also important. To the best of our knowledge, this is the longest functioning kidney transplant from a deceased donor performed in a child worldwide. Despite its risky nature at the time, this transplant paved the way for others.

Background. The clinical course of primary hyperoxaluria (PH) is greatly variable and diagnosis is often delayed. Little is known about the overall occurrence and current prognosis. Methods. We evaluated all known patients with PH residing and observed in Switzerland during the last 15 years with the help of a survey among Swiss nephrologists. Results. Of the 25 patients observed between 7/79 and 6/94 in Switzerland, 18 were alive in 1994-14 on conservative therapy and four on renal replacement therapy (RRT). Twenty-two patients had PH type 1 ; the exact type was not determined in three. The estimated prevalence of PH (type 1) is 2 per million population; the minimal incidence is 1 per 100 000 live births. Diagnosis was delayed by 8 years (median) except in infants. Five patients were pyridoxine sensitive. According to life table analysis, 20% of patients were in end-stage renal failure (ESRF) and 10% had died by the age of 15 years, and 50% were in ESRF and 20% dead at 25 years. Prognosis has improved : Five of 13 patients died during the first half of the observation period as opposed to two of 20 in the second part. Conclusions. Overall prognosis appears better than hitherto believed considering the large clinical spectrum of PH. Greater awareness of PH is needed to improve further long-term prognosis.

Secondary hyperoxaluria is due either to increased intestinal oxalate absorption or to excessive dietary oxalate intake. Certain intestinal diseases like short bowel syndrome, chronic inflammatory bowel disease or cystic fibrosis and other malabsorption syndromes are known to increase the risk of secondary hyperoxaluria. Although the urinary oxalate excretion is usually lower than in primary hyperoxaluria, it may still lead to significant morbidity by recurrent urolithiasis or progressive nephrocalcinosis. A clear distinction between primary and secondary hyperoxalurias is important. As correct classification may be difficult, appropriate diagnostic tools are needed to delineate the metabolic background as a basis for optimal treatment. We developed an individual approach for the evaluation of patients with suspected secondary hyperoxaluria. First, 24 h urines are examined repeatedly for lithogenic (e.g. calcium, oxalate, uric acid) and stone-inhibitory (e.g. citrate, magnesium) substances, and the patients are asked to fill in a dietary survey form. Urinary saturation is calculated using the computer based program EQUIL2, and the BONN-Risk-index is determined. The measurement of plasma oxalate and of urinary glycolate helps to distinguish between primary and secondary hyperoxalurias. If secondary hyperoxaluria is suspected, the stool is examined for Oxalobacter formigenes, an intestinal oxalate degrading bacterium, as lack or absence may lead to increased intestinal oxalate absorption. The last diagnostic step is to study the intestinal oxalate absorption using [13C2]oxalate. Depending on the results, various therapeutic options are available: 1) a diet low in oxalate, but normal or high in calcium, 2) a high fluid intake (>1.5 L/m2/d), 3) medications to increase the urinary solubility, 4) specific therapeutic measures in patients with malabsorption syndromes, depending on the underlying pathology, and 5) intestinal recolonization of Oxalobacter formigenes or the treatment with other oxalate degrading bacteria.

Primary distal renal tubular acidosis (dRTA) type I is a hereditary renal tubular disorder, which is characterized by impaired renal acid secretion resulting in metabolic acidosis. Clinical symptoms are nephrocalcinosis, nephrolithiasis, osteomalacia, and growth retardation. Biochemical alterations consist of hyperchloremic metabolic acidosis, hypokalemia with muscle weakness, hypercalciuria, and inappropriately raised urinary pH. Autosomal dominant and rare forms of recessive dRTA are known to be caused by mutations in the gene for the anion exchanger AE1. In order to identify a gene responsible for recessive dRTA, we performed a total genome scan with 303 polymorphic microsatellite markers in six consanguineous families with recessive dRTA from Turkey. In four of these there was an association with sensorineural deafness. The total genome scan yielded regions of homozygosity by descent in all six families on chromosomes 1, 2, and 10 as positional candidate region. In one of these regions the gene ATP6B1for the ss1 subunit of the vacuolar H(+)-ATPase is localized, which has recently been identified as causative for recessive dRTA with sensorineural deafness. Therefore, we conducted mutational analysis in 15 families and identified potential loss-of-function mutations in ATP6B1in 8. We thus confirmed that defects in this gene are responsible for recessive dRTA with sensorineural deafness.

Infections jeopardize children on immunosuppression after organ transplantation. Immunization is protective in healthy children. The aims of this study were to analyze the rate and efficacy of immunization in 62 children undergoing dialysis and renal transplantation (RTPL) between 1987 and 2000. The analysis was based on clinical findings, vaccination certificates, and measurement of specific serum antibodies. A member of the renal unit administered vaccinations. All 62 patients were immunized against diphtheria, tetanus, pertussis, poliomyelitis, measles, mumps, rubella, and hepatitis B. Since introduction in 1991 and 1995, 44 and 42 children were also vaccinated against influenza and Hemophilus influenzae type b, respectively. Of 16 patients with a negative history, 14 were given varicella vaccine; 16 children on peritoneal dialysis (PD) or with nephrotic syndrome were immunized against Streptococcus pneumoniae. All vaccinated patients had detectable serum antibodies against measles, mumps, rubella, varicella, hepatitis B, H. influenzae, and S. pneumoniae. There were 3 infections despite vaccination; 1 patient developed varicella after RTPL and 1 patient on PD had 2 episodes of peritonitis caused by H. influenzae and S. pneumoniae. In conclusion, monitoring and administration of the vaccines by the renal team enabled a high immunization rate. Whether vaccines, as documented by antibody titers, or by the low prevalence in the general population promoted the low prevalence of infections remains open, as there were at least a few vaccination failures.

The spectrum of pathology in native kidney biopsies varies considerably between different countries. Based on similar biopsy policy and joint workup, biopsy data of native kidneys of children in Yerevan (Armenia) and Zurich (Switzerland) were compared over a period of two decades (1993–2002 and 2003–2012). A total of 487 renal biopsies in Yerevan (EVN), n = 253; median age 11.2 years (range 0.8–18; 56 % males) and in Zurich (ZRH), n = 234; median age 8.7 years (range 0.1–18; 61 % males) were analyzed. Biopsies from EVN were locally analyzed by light microscopy (LM) and sent to ZRH for electron microscopy (EM) and immunohistochemistry. Biopsies from ZRH were evaluated by LM, EM, and immunofluorescence. The significant difference concerns the high frequency of amyloidosis in EVN (25.4 % in the first and 19.4 % in the second decade vs. 0 % in ZRH) and of IgA nephropathy in ZRH (30.2 % in the first and 26.1 % in the second decade vs. 8.1 in EVN). Certain forms of glomerulonephritis (membranoproliferative type I and membranous) and primary focal segmental glomerulosclerosis tended to be more frequent in EVN than in ZRH. Amyloid nephropathy due to familial Mediterranean fever is still highly frequent in Armenia with a slight decrease in the second decade. In Switzerland, the most common finding was IgA nephropathy.

The primary hyperoxalurias (PHs) are rare disorders of glyoxylate metabolism in which specific hepatic enzyme deficiencies result in overproduction of oxalate. Due to the resulting severe hyperoxaluria, recurrent urolithiasis or progressive nephrocalcinosis are principal manifestations. End stage renal failure frequently occurs and is followed by systemic oxalate deposition along with its devastating effects. Due to the lack of familiarity with PHs and their heterogeneous clinical expressions, the diagnosis is often delayed until there is advanced disease. In recent years, improvements in medical management have been associated with better patient outcomes. Although there are several therapeutic options that can help prevent early kidney failure, the only curative treatment to date is combined liver-kidney transplantation in patients with type I PH. Promising areas of investigation are being identified. Knowledge of the spectrum of disease expression, early diagnosis, and initiation of treatment before renal failure are essential to realize a benefit for patients.

We report on two children, a 12-year-old boy and a 6-year-old girl, with simultaneous occurrence of clinical and laboratory features consistent with both diarrhoea-negative haemolytic uraemic syndrome (D-HUS) and acute post-infectious glomerulonephritis (APGN). Both presented with acute renal insufficiency, hypertension and oedema. Laboratory evaluation revealed micro-angiopathic anaemia with burr cells, thrombocytopenia, elevated lactic dehydrogenase and low complement C3. Urinalysis showed marked proteinuria and haematuria. Renal biopsy was characteristic of APGN, but not of HUS. The outcome was good in both children. Conclusion. The simultaneous occurrence of diarrhoea-negative haemolytic uraemic syndrome and acute post-infectious glomerulonephritis is rare. The outcome is generally good as is expected in the latter condition in contrast to the former.

We report two pediatric patients with end-stage renal failure who developed heparin-induced thrombocytopenia type II (HIT II) on hemodialysis (HD). Both developed acute respiratory distress and chest pain within 30 min of initiating the 5th HD session. The platelets dropped during HD from 168 to 38x10(9)/l and from 248 to 109x10(9)/l, respectively. Marked clots were observed in the dialyzers. Substitution of heparin with the low molecular weight heparin dalteparin had no effect. Switching from anticoagulation to the heparinoid danaparoid resulted in immediate disappearance of all adverse effects, and further long-term HD was uneventful. HIT II was diagnosed clinically; heparin-induced platelet activation test (HIPA) and serum IgG, IgA, and IgM to heparin-platelet factor 4 complexes (HPF4) were both negative. We conclude that HIT II may occur in children on HD. HIT II is essentially a clinical diagnosis, as HIPA and antibodies to HPF4 are not always positive. Once HIT II is suspected, heparin (and low-molecular-weight heparins) should be stopped immediately. Long-term anticoagulation with danaparoid is a valuable option for patients on HD.

There is some controversy about the value of mutation analysis in the management of primary hyperoxaluria type 1 (PH1). About 50 different mutations of the AGXT gene encoding the liver-specific peroxisomal enzyme alanine:glyoxylate aminotransferase (AGT) are currently known. The three most common mutations in the Western population account for less than half of the mutant alleles, and no simple screening test is available. Does the genotype help in diagnosis, prognosis and therapy? Definitive diagnosis is indispensable if liver transplantation is considered and can under certain circumstances be established by mutation analysis, but a liver biopsy is still necessary to determine AGT activity in a number of cases. Prognosis is difficult to assess due to a large clinical variation, despite identical mutations. Although the homozygous 508G>A (Gly170Arg) mutation appears to be associated with a better (and 33insC with a worse) prognosis, there are too many exceptions for precise prediction. Pyridoxine responsiveness can be anticipated in some genotypes (508G>A (Gly170Arg) and 454T>A (Phe153Ile)), but it should still be tested for in all patients. Genetic testing is thus clinically helpful but has clear limitations.

Following the earthquake in December 1988, a long-term project was developed: starting from haemodialysis, it was extended to basic nephrology and urology, with a programme for schooling and psychosocial care. Medical training had first priority. The programme relied on robust and often second-hand equipment and voluntary work. The approach chosen (an inverse help programme, from sophisticated to basic medicine) strongly stimulated motivation and proved to be practicable.

Therapy of steroid-dependent idiopathic nephrotic syndrome is often unsatisfactory. Since 1986 we have treated nine children (six male and three female), aged 3-16 years, with cyclosporin A (CsA) during 2.0-5.2 (median 3.1) years. All had minimal change disease on renal biopsy and had previously received cyclophosphamide. Mean daily dosage of CsA was 4.1 mg/kg (range 2.7-5.8) and mean whole blood trough level was 220 ng/ml (range 141-271). The relapse rate decreased from 3.4/patient year before CsA to 0.55 on CsA. Discontinuation of CsA or reduction below 2 mg/kg daily was always followed by a relapse. The overall relapse rate, including the period with very low-dose CsA, was 0.95/patient year. Four patients required additional low-dose alternate-day prednisone. Repeat renal biopsy showed minimal change disease in eight patients and focal segmental glomerulosclerosis in one; CsA-toxicity was mild in two and moderate in one. The latter was the only patient with slightly reduced glomerular filtration rate. Two boys with delayed puberty spontaneously matured and reached expected final height. We conclude that long-term low-dose CsA is very effective and steroid-sparing. Its use is justified in selected patients, particularly in those with numerous relapses and in male patients before and during puberty, as long as renal function and CsA-toxicity are carefully monitored.

The molar ratios of oxalate and glycolate over creatinine were determined in single urine samples of 26 infants and 27 children aged 1-5 years. In 135 children aged 5-16 years, two urine specimens were collected, one before breakfast and one at noon. Oxalate was determined by oxalate oxidase, and glycolate was measured by a colorimetric method (improved chromatotropic acid--sulphuric acid assay after prior purification by cation and anion exchanger). Both ratios (expressed in mmol/mol creatinine and analysed on a log-normal basis) were highest in infants 0-6 months old [mean oxalate 147 (95% confidence interval: 60-360), mean glycolate 175 (72-425)]. The mean oxalate ratio was 72 mmol/mol (29-174) at the age of 7-24 months, 44 (19-101) at the age of 2-5 years and 22 (12-40) in adolescents aged 16 years. Molar glycolate ratios were higher, but disclosed the same pattern. Oxalate and glycolate ratios in fasting urines did not differ significantly from those in noon samples (except glycolate in the oldest age group). Oxalate ratios correlated well with glycolate ratios in children up to 5 years of age only. Random urine samples are thus suitable for screening. However, interpretation of data requires use of age-specific reference values that are based on comparable methods.

Xanthinuria type I is a rare disorder of purine metabolism caused by xanthine oxidoreductase or dehydrogenase (XDH) deficiency. We report a family with two affected children out of 335 pediatric stone patients studied since 1991 in Armenia. The propositus, a 13-month-old boy, presented with abdominal pain and urinary retention followed by stone passage (0.9×0.6 cm). Infrared spectroscopy in Yerevan revealed a pure xanthine stone. Family examination in the parents and brother was normal, but the propositus and his 8-year-old asymptomatic sister had hypouricemia, hypouricosuria, and high urinary excretion of hypoxanthine and xanthine. Ultrasonography in the index patient showed bilateral stones requiring pyelolithotomy. High fluid intake and purine restriction did not prevent further stone passages. The affected asymptomatic sister had a small pelvic stone (4 mm). Mutation analysis revealed a heterozygous novel base pair substitution in exon 25 of the XDH gene (c.2810C>T), resulting in an amino acid substitution (p.Thr910Met). The second mutation could not be detected. Despite this, the heterozygous mutation, the chemical findings, and the positive allopurinol test altogether prove xanthinuria type I, which may present wide clinical intrafamilial variation. Diagnosis is suspected usually from low serum uric acid. No specific therapy is available.

Objective Long-term outcome of steroid-sensitive idiopathic nephrotic syndrome (SSNS) in children is usually considered benign, although data on follow-up into adulthood are scarce. The aim of this study was to investigate adults who had childhood SSNS regarding their relapse rate, growth, and renal and extrarenal morbidity. Study design Adult patients (n = 42, 26 males) were evaluated at a median age of 28.0 (18.1 to 46.9) years and a median follow-up of 22.0 (2.9 to 39.0) years since diagnosis. Results Fourteen of 42 (33%) patients relapsed in adulthood. The number of relapses during childhood and adolescence and a complicated course—administration of steroid-sparing medication such as cyclophosphamide, chlorambucil, and cyclosporin A—were identified as risk factors. Final adult height (median SD score −0.4, range −3.3 to +1.3) and body mass index (BMI) were normal. Renal function was normal in all patients, and overall morbidity was low. Only eight patients (three males) had children. Cytotoxic therapy was identified as a major factor contributing to childlessness. Conclusion Relapses in adulthood were common in pediatric patients with SSNS. Growth and renal function were normal, and overall morbidity was low. Yet, transition to an adult nephrologist is recommended for all children with relapsing SSNS.

A 3.5-year-old boy living in a remote Armenian villagewas admitted to the hospital in Yerevan in March 2002with a history of polydipsia since the age of 6 months,bowed legs since he started to walk at the age of 1 yearand an increasingly large abdomen. The child was verysmall [height: 74cm ( 5.9 SDS)] but alert, had amoonlikeface, agrossly enlargedliver(10cm below thecostal margin) and a waddling gait due to severe ricketswith genua vara (Figure 1). Psychomotor developmentwas adequate for age. The liver was markedly enlargedatultrasonography,butofhomogeneousstructure.Thekidneys were large (length: 76mm; normal for height:45–70mm).Laboratory examination showed proximal tubulardysfunctionwithgeneralizedaminoaciduria,butgluco-suria was excessive with 213mmol¼38.4g per 24h or133g/1.73m

Hypercalciuria and nephrocalcinosis are not uncommon in patients with Wilson's disease but have only once been reported as the presenting sign. We diagnosed Wilson's disease in a 17-year-old male patient 6 years after his first episode of gross hematuria and 2 years after detection of hypercalciuria and nephrocalcinosis. Therapy with penicillamine resulted only in a moderate reduction of urinary calcium excretion but oxalate excretion increased.

Background Pediatric respiratory allergies are increasing problem in Armenia being underestimated according to official reports. “Allergic Sensitization and Diseases in Armenian Children” study has been conducted to assess the prevailing sensitizations to inhalant allergens of Armenia using the standardized panel and method of PEP study (Pan-European standard Skin prick test study) conducted by Global Allergy and Asthma European Network (GA2LEN).

To study prospectively the risk factors and etiology of urolithiasis in all stone patients aged

AIMS—To investigate urinary oxalate excretion in children with urolithiasis and/or nephrocalcinosis and to classify hyperoxaluria (HyOx). METHODS—A total of 106 patients were screened. In those in whom the oxalate: creatinine ratio was increased, 24 hour urinary oxalate excretion was measured. Liver biopsy and/or genomic analysis was performed if primary hyperoxaluria (PH) was suspected. Stool specimens were examined for Oxalobacter formigenes in HyOx not related to PH type 1 or 2 (PH1, PH2) and in controls. RESULTS—A total of 21 patients screened had HyOx (>0.5 mmol/24 h per 1.73 m2); they were classified into five groups. Eleven had PH (PH1 in nine and neither PH1 nor PH2 in two). Six had secondary HyOx: two enteric and four dietary. Four could not be classified. Seven patients had concomitant hypercalciuria. Only one of 12 patients was colonised with O formigenes compared to six of 13controls. CONCLUSIONS—HyOx is an important risk factor for urolithiasis and nephrocalcinosis in children, and can coexist with hypercalciuria. A novel type of PH is proposed. Absence of O formigenes may contribute to HyOx not related to PH1.

Dent's disease is an X-linked renal tubular disorder characterized by low-molecular-weight proteinuria, hypercalciuria, nephrocalcinosis, nephrolithiasis, and renal failure. Patients with Dent's disease may also suffer from rickets and other features of the renal Fanconi Syndrome. Patients may have mutations in the X-linked renal chloride channel gene, CLCN5, which encodes a 746-amino-acid protein with 12-13 transmembrane domains. We have investigated the 11 coding exons of CLCN5 for mutations in eight unrelated patients with Dent's disease. Leukocyte DNA was used for the polymerase chain reaction amplification of CLCN5 and the products analyzed for single-stranded conformational polymorphisms (SSCPs). Abnormal SSCPs were sequenced and revealed eight mutations. These consisted of three nonsense mutations (Arg34Stop, Arg648Stop, Arg704Stop), four deletions involving codons 40, 86, 157, and 241, and one acceptor splice consensus sequence mutation tgcag --> tgaag. The mutations were confirmed either by restriction endonuclease or sequence-specific oligonucleotide hybridization analysis. In addition, an analysis of 110 alleles from 74 unrelated normal individuals demonstrated that the DNA sequence changes were not common polymorphisms. All of the mutations predict truncated chloride channels that are likely to result in a functional loss. Thus, our findings expand the spectrum of CLCN5 mutations associated with Dent's disease and the results will help to elucidate further the functional domains of this novel chloride channel.

Measurement of oxalate in urine is important for the diagnosis of primary hyperoxaluria (McKusick 259900) and the secondary forms produced by excessive intake or abnormal intestinal absorption of oxalate (1). Determination of glycolic acid is essential for the diagnosis of primary hyperoxaluria type 1. Finally, to estimate the risk of stone formation in calcium oxalate urolithiasis and nephrocalcinosis, simultaneous determination not only of calcium but also of citrate (a potent inhibitor of calcium oxalate and calcium phosphate crystallization) and other constituents (electrolytes, phosphate and sulfate) is required to calculate urinary calcium saturation (2). Ion-chromatography HPLC (3)(4) and specific enzymatic assays (5)(6) are available only in specialized laboratories. In addition, preservation and storage of liquid samples may influence the stability of oxalate and glycolate (7). Use of urinary filter spots is a practical alternative for the collection and safe transport of samples to be analyzed for many metabolic disorders. To evaluate the age-related changes of oxalate, glycolate, citrate, and sulfate in a pediatric population, we developed an automated ion-chromatography system for the simultaneous measurement of these anions in urine and established their reference values for liquid urine samples as well as for dried urine on filter paper. We studied 20 individuals from each age group ( 16 years), all without renal or metabolic disease, all on a routine food intake at the time of study. The urines were preserved with 6 mol/L HCl at pH 1–2 to prevent nonenzymatic conversion of ascorbate to oxalate. Filter paper strips (3 × 5 …

Few data for normal urinary oxalate (Ox) and calcium (Ca) excretion related both to gestational age and nutritional factors have been reported in preterm or term infants. We therefore determined the molar Ox and Ca to creatinine (Cr) ratios in spot urines from 64 preterm and 37 term infants aged 1–60 days, either fed formula or human milk (HM). Only vitamin D was supplemented; renal or metabolic diseases were excluded. Urinary Ox/Cr ratio was higher in preterm than in term infants, both when formula fed (1st month 253 vs. 180 mmol/mol and 2nd month 306 vs. 212 mmol/mol; P

We describe two siblings (female and male) with progressive tubulo-interstitial nephropathy and cholestatic liver disease. The main characteristics were progressive renal failure and elevated liver enzymes (AST, ALT and gamma-GT). Dialysis was started at the age of 1.9 and 6.5 years, respectively. Renal histology disclosed sclerosed glomeruli and atrophic tubules; the interstitium was fibrotic and infiltrated by lymphocytes. Endoscopic retrograde cholangiopancreatography revealed segmental irregularities and narrowing of the intrahepatic bile ducts, consistent with early primary sclerosing cholangitis. Liver histology showed enlarged portal triads, mild proliferation and inflammation of bile ducts, and fibrosis. At 5.9 years the girl underwent a successful renal transplantation whereas the boy is still on dialysis.The association of progressive tubulointerstitial nephropathy and cholestatic liver disease, consistent with early primary sclerosing cholangitis, constitutes a distinct autosomal recessive entity.

Atypical, non-diarrhoea associated haemolytic uraemic syndrome (D-HUS) is a heterogeneous disorder with a generally poor outcome, although this view has now been questioned. The clinical and laboratory features of 23 children with D-HUS, representing a third of all patients with HUS seen during the last 26 years, were examined. The median age was 4.9 years (range 3 days-13.8 years). Twenty one children (91%) survived the initial phase. All patients except six infants aged18 months required dialysis (74%). Hypertension (43%), cardiomyopathy (43%), and cerebral convulsions (48%) were common. Nineteen (83%) children were followed up for a median period of 5.5 years (range 0.5-23.4). Only five (26%) patients, among them four infants, recovered completely. Six (32%) patients had one to 10 recurrences, including two siblings with neonatal onset, and eight (42%) developed end stage renal failure. Five children underwent cadaveric renal transplantation, with recurrence and subsequent graft failure in two. Four children died, resulting in an overall mortality of 26%. Atypical HUS is heterogeneous with regard to epidemiology, pathophysiology, and outcome. Children with a recurrent, familial, or neonatal course have worse outcomes; in contrast, infants not requiring dialysis in the acute phase have a better prognosis.

Primary hyperoxaluria type 1 (PH1) is a rare autosomal recessive disease caused by a deficiency of alanine:glyoxylate aminotransferase (encoded by the AGXT gene). Primary hyperoxaluria type 1 is characterized by the elevated urinary excretion of oxalate and glycolate, and the deposition of insoluble calcium oxalate in the renal parenchyma and urinary tract. In the present study, we investigated an unusual family containing four affected individuals in two different generations. Based on our genetic, enzymic, metabolic, and clinical analyses, we have come to the following conclusions. First, although the pattern of inheritance of PH1 is usually horizontal (ie, all patients in the same generation), as expected for an autosomal recessive disease, it can sometimes show a vertical (pseudodominant) pattern of inheritance (ie, patients in more than one generation) due to the segregation within a family of three, rather than two, mutant AGXT alleles. Second, affected members of such a family can manifest very different clinical phenotypes both within and between generations. Although the clinical differences between generations might be at least partly due to differences in AGXT genotype, differences can equally occur within the same generation in individuals who possess the same AGXT genotype. Finally, individuals with PH1 at the level of the AGXT genotype might remain asymptomatic and undiagnosed for many years. The consequences of these findings for the clinical management and genetic counseling of families with PH1 are profound and wide-ranging.

Previous studies have shown that there is a higher risk of developing nephrocalcinosis in pre-term infants receiving parenteral nutrition (TPN) than in those receiving breastmilk nutrition. It was concluded from these studies that the nephrocalcinosis might be due to the amino acid solution in TPN. The aim of this study was to measure the effects on a number of urine parameters in babies given amino acid solutions

Urinary citrate is a potent inhibitor of calcium oxalate (CaOx) crystallization, but oral citrate has rarely been used in patients with primary hyperoxaluria (PH). We studied the effect of sodium citrate administration (0.1-0.15 g/kg/day) on urinary citrate excretion and CaOx saturation in seven paediatric patients and the clinical response to long-term treatment (average 4 years) in five patients. Urinary citrate increased from 0.73 to 2.54 mmol/24 h/1.73 m2 and urinary saturation for CaOx (calculated by equil 2) decreased from 11.41 to 6.79 (for both, p < 0.02). Long-term administration of alkali citrate [0.15 g (0.5 mmol)/kg/day] resulted in stable or improved renal function in three and slow deterioration in two partially non-compliant patients. Alkali citrate is effective in patients with PH.

This paper summarises a symposium concerned with the provision of care for children with kidney disease in developing countries. Better organisation of services is required to prevent waste of resources, with the emphasis on team work between professionals, shared care with local health care personnel remote from the paediatric nephrology unit and good communications. Families need to be educated and provided with appropriate information so that they can care for their child at home. Technology should be simple and robust and the staff using it should be fully trained to maintain it in use. Therapies should be definitive where possible, because long-term supervision of treatment is often difficult. Effective but inexpensive medications should be used where possible. Twinning of developing and richer countries is valuable to transfer technology, help with training and assist in care through the development of personal contacts.

Nephrocalcinosis is a well-known complication in pre-term infants1, 2. Hypercalciuria induced by furosemide administration was at first considered to be the main cause of nephrocalcinosis1, 2. Dexamethasone therapy and long-term oxygen requirements have also been considered causative3, 4. Total parenteral nutrition (TPN) was presumed to increase the risk of renal calcification because of increasing urinary oxalate excretion5.

Urinary lithogenic and inhibitory factors were studied in 27 preterm infants; 16 had total parenteral nutrition (TPN) and 11 had breastmilk with an additional glucose-sodium chloride infusion. Urines were collected for 24 hours on day 2 (period A), day 3 (B), and once between days 4 and 10 (C). Urinary calcium oxalate saturation was calculated by the computer program EQUIL 2. Renal ultrasonography was performed every second week until discharge. The calcium/creatinine ratio increased in infants on TPN (A 0.91; C 1.68 mol/mol) and was significantly higher at period C than that in infants on breastmilk/infusion (A 0.52; C 0.36). The oxalate/creatinine ratio was persistently higher with TPN (203 mmol/mol) than with breastmilk/infusion (98; 137). The citrate/creatinine remained constant with TPN (0.44 mol/mol), whereas it increased significantly with breastmilk/infusion (0.26; 0.49). Calcium/citrate rose considerably with TPN, but decreased with breastmilk/infusion to a significantly lower level than with TPN. The urinary calcium oxalate saturation increased with TPN (2.4; 4.5) and decreased with breastmilk/infusion (2.1; 1.5) to a significantly lower value than with TPN. Nephrocalcinosis developed in two infants on TPN. Mean daily calcium intake was similar in both groups, whereas protein, sodium, and phosphorus intake were significantly higher on TPN. It is concluded that the increase in urinary calcium oxalate saturation observed with TPN is due to the combined effect of an increased urinary calcium excretion and higher urinary oxalate/creatinine and calcium/citrate ratios. The changes observed are likely to be caused by TPN itself, which differs in several respects from breastmilk feeding.

The prognosis of primary hyperoxaluria (PH) is not only related to endogenous oxalate production and the response (if any) to pyridoxine (in type I), but is greatly influenced by extrarenal factors like dehydration. The earlier the diagnosis of PH, the better the chances of improving the prognosis in individual patients. Measures to enhance the solubility of calcium oxalate are important. Besides ensuring at all times a generous fluid intake (>2 l/m2), administration of alkali citrate (0.15 g/kg), which has not been advocated so far in PH, appears very promising. We studied the effect of sodium citrate in six patients with PH. Mean urinary citrate excretion (mmol/day per 1.73 m2) without oral citrate was very low (0.57) and rose to 2.49 with citrate administration. This was accompanied by a significant decrease in the calcium oxalate saturation (calculated by equil 2) from 11.7 to 6.9 (P

Eighteen patients aged 5-18 years on regular dialysis had a packed cell volume (PCV) less than 0.27. On treatment with epoetin alfa (EA) PCV increased by 0.05 or more in all patients. Iron supplementation was necessary in 13 patients with a ferritinaemia less than 300 micrograms/l before study. During treatment, plasma potassium increased significantly and more vigorous antihypertensive measures were required in 8 patients, 5 of them being already on antihypertensive drugs before EA. Iliofemoral thrombosis occurred in 1 patient 10 days after renal transplant. The data indicate that EA ameliorates the anaemia of chronic renal disease. The main concerns arising during treatment with EA are hyperkalaemia, arterial hypertension and possibly thrombosis.

Primary hyperoxaluria (PH) is a rare inborn error of metabolism characterized by increased production of oxalate and glycolate [1]. Urinary excretion of oxalate always exceeds 100 mg (1.1 mmol), and usually 200 mg (2.2 mmol) per day, as compared to less than 45 mg (0.5 mmol) in normals [1]. Elevated urinary excretion of oxalate not only leads to formation of calcium oxalate stones and to repeated attacks of renal colics, but also results in crystal deposition in the renal interstitium, which induces fibrosis and nephrocalcinosis. Renal damage, in turn, leads to oxalate retention and involvement of other organs, primarily of the bones, the arteries, the cardiac conduction system, the retina, and the neuromuscular system. Two types of PH have been described, of which type I (glycolic aciduria) is much more common than type II (L-glyceric aciduria) [2]. The discussion will therefore focus on PH type I. Apart from these two types, there appears to exist yet another variety of PH, in which the urinary excretion of both glycolate and glycerate are normal [3–5].