Trafficking of Shiga toxin/Shiga-like toxin-1 in human glomerular microvascular endothelial cells and human mesangial cells

This study has determined the intracellular transport route of Shiga-like toxin (Stx) and the highly related Shiga toxin in human glomerular microvascular endothelial cells (GMVECs) and mesangial cells. In addition, the effect of tumor necrosis factor-alpha (TNF-alpha), which contributes to the pathogenesis of hemolytic-uremic syndrome, was evaluated more profound. Establishing the transport route will provide better understanding of the cytotoxic effect of Stx on renal cells. For our studies, we used receptor-binding B-subunit (StxB), which is identical between Shiga toxin and Stx-1. The transport route of StxB was studied by immunofluorescence microscopy and biochemical assays that allow quantitative analysis of retrograde transport from plasma membrane to Golgi apparatus and endoplasmic reticulum (ER). In both cell types, StxB was detergent-resistant membrane associated and followed the retrograde route. TNF-alpha upregulated Gb3 expression in mesangial cells and GMVECs, without affecting the efficiency of StxB transport to the ER. In conclusion, our study shows that in human GMVECs and mesangial cells, StxB follows the retrograde route to the Golgi apparatus and the ER. TNF-alpha treatment increases the amount of cell-associated StxB, but not retrograde transport as such, making it likely that the strong TNF-alpha-induced sensitization of mesangial cells and GMVECs for the toxic action of Stx is not due to a direct effect on the intracellular trafficking of the toxin.

Early transient leg swelling at the side of renal transplant in two children

Two children are described with a huge leg swelling shortly after renal transplantation. The swelling was located at the side of the renal transplant. The swelling was caused by the compression of the iliac vein by the renal transplant combined with perirenal fluid collection. Doppler flow studies allow the exclusion of thrombosis as an explanation for the swelling. An aggressive treatment should be avoided. However, anticoagulation is required.

ACE inhibitorenalapril diminishes albuminuria in patients with cystinosis

BACKGROUND/AIMS

Cystinosis, a rare autosomal recessive disease, manifests with renal Fanconi syndrome during the first year of life. Interstitial damage is a major cause of renal failure in patients with cystinosis. We presume that albuminuria contributes to the development of renal failure in these patients. The aim of this study was to examine whether the administration of ACE inhibitor enalapril diminishes albuminuria in patients with cystinosis.

METHODS

Five patients with cystinosis aged 4 - 9 years were studied. All patients had Fanconi syndrome and were treated with cysteamine. Median creatinine clearance was 48 ml/min/1.73 m2 (range 21 - 61). The excretion of albumin and alpha1 microglobulin as well as arterial blood pressure and serum creatinine were evaluated before and at 3 months on oral administration of enalapril (0.15 mg/kg once daily).

RESULTS

At 3 months on enalapril, albuminuria decreased in all patients (1,042 vs 629 mg per 24 h, p < 0.05). The median reduction of albuminuria was 43% (range: 4 - 72%, p < 0.05). Urinary excretion of alpha1 microglobulin remained constant. Systolic blood pressure decreased from median 110 - 100 mmHg (p < 0.05), while diastolic blood pressure remained stable (median 60 mmHg). Creatinine clearance decreased from median 48 - 45 ml/min/1.73 m2 (p < 0.05) and returned to previous values after discontinuation of enalapril.

CONCLUSION

ACE inhibitor enalapril diminishes albuminuria in patients with cystinosis and might be used in these patients in order to slow the progression of renal insufficiency attributed to proteinuria.

Autosomal recessive renal glucosuria attributable to a mutation in the sodium glucose cotransporter (SGLT2)

Patients with primary renal glucosuria have normal blood glucose levels, normal oral glucose tolerance test results, and isolated persistant glucosuria. Congenital renal glucosuria is postulated to be attributable to defects in the SGLT2 gene. The Na(+)/glucose cotransporter gene SGLT2 (= SLC5A2) was analyzed in a Turkish patient with congenital isolated renal glucosuria. Genomic DNA was used as a template for amplification by the polymerase chain reaction of each of the 14 exons of the SGLT2 gene. The amplification products were sequenced. DNA sequence analysis revealed a homozygous nonsense mutation in exon 11 of the SGLT2 gene leading to the formation of a truncated cotransporter. Both parents and a younger brother, all three without renal glucosuria, are heterozygous for the nonsense mutation. Our data provide the first direct evidence of an etiologic role for the sodium/glucose cotransporter type 2 in the pathogenesis of renal glucosuria.

Autosomal recessive hypophosphataemic rickets with hypercalciuria is not caused by mutations in the type II renal sodium/phosphate cotransporter gene

BACKGROUND

At present the genetic defect for autosomal recessive and autosomal dominant hypophosphataemic rickets with hypercalciuria (HHRH) is unknown. Type II sodium/phosphate cotransporter (NPT2) gene is a serious candidate for being the causative gene in either or both autosomal recessive and autosomal dominant HHRH. In the present study we tested this hypothesis in one autosomal recessive family.

METHODS

The gene structure of human NPT2 is known. We tested the complete open reading frame in the affected siblings by polymerase chain reaction in combination with automatic DNA sequencing for the presence of mutations.

RESULTS

We did not observe disease-causing mutations in the NPT2 gene of the affected siblings. A T855C polymorphism resulting in a histidine to arginine transition was present in the open reading frame of NPT2. The polymorphism was present in both affected as well as unaffected family members.

CONCLUSION

The hypothesis that a defect in the NPT2 gene could be an underlying cause for autosomal recessive HHRH could not be sustained in our study.

Immunoglobulins in chronic renal failure of childhood: effects of dialysis modalities

BACKGROUND

It is not clear whether low serum levels of IgG (subclasses), previously demonstrated in children on peritoneal dialysis (PD), are related to the PD procedure or to factors associated with chronic renal failure (CRF). The aim of our study was to analyze the effect of PD on serum and PD effluent (PDE) IgG and subclass levels in children with end-stage renal failure.

METHODS

We measured albumin, IgG, IgA, IgM, and IgG subclasses in serum and PDE from children on PD (N = 40) and compared the serum values with those of children treated with hemodialysis (HD, N = 23) or presenting with CRF but not yet dialyzed (CRF; N = 63), and with a group of healthy controls (HCs; N = 67). Sixteen PD children could be followed sequentially from before starting PD and eight during a peritonitis episode.

RESULTS

Forty percent of the PD children showed reduced serum IgG2 levels (P = 0.0003) compared with 35% in HD (P = 0.006), 33% in CRF (P = 0.001), and 9% in HC children. IgG1 deficiencies were observed in 25% of PD patients (P < 0.0001), 4% of HD (P = NS), 16% of CRF (P = 0.0005), and 0% of HC children. IgG3 and IgG4 deficiencies were observed less frequently. Peritoneal clearances were similar for total IgG, IgG1, IgG2, and IgG4, but were lower for IgG3 (P < 0.05). No relationships were found between clearances and age or duration of PD treatment. Total IgG (P = 0. 003) and IgG1 (P = 0.002) levels declined just after starting PD. Peritonitis was associated with temporarily increased peritoneal loss of Ig, while the serum concentrations were unaffected. No significant relationship was found between the peritonitis incidence and reduced IgG or subclasses. However, all children with two or more peritonitis episodes per year had a reduced Ig level.

CONCLUSIONS

Although the mean serum concentrations of immunoglobulins were normal in all studied groups, a deficiency of one or more IgG subclasses was present in all groups with renal failure, suggesting inhibition of their synthesis by the uremic state. Ig deficiencies were more frequently found in PD, likely caused by protein loss in PDE. A high peritonitis incidence was associated with reduced serum Ig levels.

Fungal bezoars as a cause of renal insufficiency in neonates and infants--recommended treatment strategy

Fungal bezoars may be a cause of urinary tract obstruction and acute renal failure in neonates and young infants. We describe a female very low birth weight infant (25+3 weeks, 795 gram) who developed renal insufficiency on the basis of systemic fungal infection with fungal bezoars in both kidneys. The girl was treated by local irrigation of the kidneys and bladder with amphotericin B via percutaneously inserted bilateral nephrostomy catheters, in combination with intravenous fluconazol. Renal function subsequently improved and after 11 weeks of treatment the bezoars had disappeared sonographically. Follow-up of this child and the one we similarly treated for fungal bezoars before, however, shows suboptimal renal function as assessed by the clearance of creatinine and the mercapto acetyl triglycine scan (MAG III). Until now, insufficient data are available yet to assess with certainly the long-term effects of fungal bezoars on renal function. Based on our experience and a review of the recent literature (1980-1996) on systemic candidal infections in premature infants, we recommend to perform regular renal ultrasound in any case of systemic candidal infection in a prematurely born infant. If candidal bezoars are found with pelvic obstruction, we suggest to start treatment by the insertion of bilateral nephrostomy catheters and local irrigation with amphotericin B in combination with systemic antifungal agents, aiming at both the restoration of renal function and the eradication of the fungal infection.

Congenital nephrotic syndrome: a novel phenotype of type I carbohydrate-deficient glycoprotein syndrome

Type I carbohydrate-deficient glycoprotein (CDG) syndrome is a genetic multisystem disorder generally without overt renal problems. We report a neonate with neurological abnormalities and congenital nephrotic syndrome of diffuse mesangial sclerosis type. Serum transferrin isoelectric focusing showed the typical abnormalities of type I CDG syndrome. Normal transferrin focusing findings in other patients with similar renal problems excluded the possibility of a secondary biochemical phenomenon. The diagnosis of type I CDG syndrome was confirmed by demonstration of a deficiency of phosphomannomutase. No evidence of pontocerebellar atrophy was found in imaging or at autopsy. We conclude that congenital nephrotic syndrome may occur in type I CDG syndrome, and that this diagnosis should be considered in patients with congenital nephrotic syndrome. Absence of pontocerebellar atrophy does not exclude the diagnosis of type I CDG syndrome.

[2 children with stridor and a thymus in the posterior mediastinum]

Two infants are described with an inspiratory and expiratory stridor with apnea. X-ray examination showed a mass in the posterior mediastinum. For this reason both infants underwent a diagnostic thoracotomy because detailed study didn't resolve the problem. An aberrant localized thymus was found in both infants. In both infants, however, the complaints persisted after the operation. Both infants needed a second operation to relieve the stridor, which appeared to be due to (primary and secondary) tracheomalacia. This article describes shortly the embryology of the abnormally located thymus. The possibilities to diagnose a posterior mediastinal mass without thoracotomy are also described. Using magnetic resonance imaging (MRI), the posterior located thymus can be diagnosed noninvasively in most cases. The aberrantly positioned thymus should be included in the differential diagnosis of a posterior mediastinal mass, otherwise invasive methods are needed to come to the good diagnosis.

Supplementation of vitamin K in pregnant women receiving anticonvulsant therapy prevents neonatal vitamin K deficiency

OBJECTIVE

The null hypothesis of this study is that extra vitamin K administered to pregnant women on a regimen of enzyme-inducing anticonvulsant therapy will not decrease the frequency of symptoms of vitamin K deficiency in their neonates.

STUDY DESIGN

A multicenter case-control study was performed on 16 pregnant women on anticonvulsant therapy who received 10 mg of vitamin K1 daily from 36 weeks of pregnancy onward. Concentrations of PIVKA-II (protein induced by vitamin K absence for factor II) and of vitamin K1 were determined in cord blood and compared with those in 20 controls.

RESULTS

In none of 17 cord samples was PIVKA-II detectable, compared with 13 of 20 in controls (chi 2, p < 0.001). Median cord vitamin K1 level was 530 pg/ml compared with below detection limit in most controls.

CONCLUSIONS

Antenatal vitamin K1 treatment decreases the frequency of vitamin K deficiency in neonates of mothers on anticonvulsant therapy.

Increased incidence of neonatal vitamin K deficiency resulting from maternal anticonvulsant therapy

OBJECTIVE

The null hypothesis of our study is that the incidence of vitamin K deficiency in mother-infant pairs exposed to anticonvulsant drugs is not higher than in controls.

STUDY DESIGN

In this multicenter observational case-control study, 25 pregnant women receiving anticonvulsant therapy and 25 pregnant controls were studied for PIVKA-II (protein induced by vitamin K absence of factor II) and vitamin K1 concentrations at 32 weeks' gestation and at delivery.

RESULTS

PIVKA-II was detectable in 54% of cord samples of the anticonvulsant group and in 20% of controls (chi 2, p = 0.01). In both groups vitamin K1 cord blood levels were predominantly below the detection limit. Maternal vitamin K1 concentrations were lower in women with epilepsy than in controls (Wilcoxon's rank sum test, p < 0.05), but PIVKA-II was rarely present.

CONCLUSIONS

The incidence of vitamin K deficiency is increased in neonates exposed to anticonvulsant drugs prenatally. Their mothers, however, are rarely vitamin K deficient.

Acute renal failure in a neonate due to pelviureteric candidal bezoars successfully treated with long-term systemic fluconazole

Systemic candidiasis with renal involvement is a rare but well-recognized complication during intensive care treatment in very-low-birth-weight infants. We report a term neonate who developed anuria associated with bilateral bezoar formation in the renal pelvis and candidemia. The treatment consisted of placement of a nephrostomy tube in the left kidney, short-term irrigation with amphotericin B and iv, and later, oral administration of fluconazole.

[Good results of cyclophosphamide in steroid toxicity in the treatment of nephrotic syndrome caused by minimal-lesion glomerulopathy in childhood]

The effect of cyclophosphamide therapy was evaluated in the treatment of children with nephrotic syndrome due to minimal lesions. Most of the children, 37 out of 43, presented with frequent relapsing nephrotic syndrome. Cyclophosphamide was given in a dose of 3 mg/kg body weight/day for a period of 8 weeks. Two patients received two courses, one patient received three courses. Only one patient, who was steroid-resistant, did not respond to cyclophosphamide therapy (therapy was, however, stopped after 3 weeks because of haemorrhagic cystitis). 57% of the patients were still in remission after 18 months (n = 37) and 50% after 30 months (n = 34). A haemorrhagic cystitis developed in 3 patients and leucopenia in 2 patients. From this study, which confirms data reported in literature, it can be concluded that cyclophosphamide has a beneficial effect in children with minimal lesion nephrotic syndrome and steroid toxicity.

Analysis of chromosome aberrations and sister chromatid exchanges in peripheral blood lymphocytes of newborns after vitamin K prophylaxis at birth

In many countries vitamin K prophylaxis at birth is recommended to prevent bleeding in infants due to vitamin K deficiency. Because the incidence of clinical vitamin K deficiency is very low, such a vitamin K administration should be completely safe. However, an increase in sister chromatid exchanges in lymphocytes of fetal sheep 24 h after injection of vitamin K1 has been reported. Therefore, a study concerning genotoxicity of vitamin K1 in man was conducted. Sister chromatid exchanges and chromosome aberrations were analyzed in peripheral blood lymphocytes of six newborns 24 h after intramuscular administration of 1 mg vitamin K1 and in six control neonates. The mean number of sister chromatid exchanges per metaphase in the vitamin K group was 8.88 +/- 1.22 as compared with 9.05 +/- 1.14 in the control group (NS). The mean number of chromosome aberrations per 100 mitoses was 3.00 +/- 2.61 in the vitamin K group and 2.50 +/- 1.87 in the control group (NS). Vitamin K1 plasma concentrations ranged from 115 to 1150 ng/mL (255 to 2555 x 10(-9) M) in the supplemented group, a 5000-fold rise as compared with the control group (p less than 0.01). We did not find any evidence for genetic toxicity due to the administration of 1 mg vitamin K1 intramuscularly to the newborn child.

Urinary excretion of prostaglandins during infancy and childhood: influence of age, sodium restriction and posture

The influences of age, sodium restriction and posture on 24-hour urinary excretion of prostaglandin E2 (PGE2), prostaglandin F2 alpha (PGF 2 alpha), 6-keto-prostaglandin F1 alpha (6-keto-PGF 1 alpha) and thromboxane B2 (TXB2) were investigated in 111 healthy children and youngsters in the age between 1 day and 16 years. A considerable degree of variation was found in normal 24-hour urinary prostaglandin excretion in all age groups. There was no significant effect of age on the urinary excretion of prostaglandins when data were corrected for body surface area. In addition, sodium restriction and posture had no influence on the excretion of PGE2, PGF 2 alpha, 6-keto-PGF 1 alpha and TXB2. Our results indicate that in the first days of life the kidney already has the capacity to synthesize prostaglandins in amounts comparable to older children.

Nephrosis in two siblings with infantile sialic acid storage disease

The diagnosis of infantile sialic acid storage disease (ISSD) was established in two siblings on the basis of typical clinical signs and the biochemical findings of hyperexcretion and intracellular storage of free sialic acid. A severe, steroid resistant nephrosis occurred in both siblings. The activities of lysosomal enzymes, including sialidase, were normal. A combined detection method for sialic acids with Limax flavus agglutinin labelling and phosphotungstic acid staining showed severely alterated sialic acid components in epithelial kidney cells and indicate a causal relationship between the nephrosis and the underlying biochemical defect. Further observations of ISSD patients with renal involvement will prove if a separate nephropathic phenotype exists.

Three-point linkage analysis using multiple DNA polymorphic markers in families with X-linked nephrogenic diabetes insipidus

The gene for X-linked nephrogenic diabetes insipidus (NDI), a disorder which, if untreated, causes severe dehydration, mental retardation, and possibly death in affected males, has been mapped recently to the Xq28 band through demonstration of linkage to the DX552 locus and other DNA markers (N. Knoers et al., 1987, Cytogenet. Cell Genet. 46:640; M. Kambouris et al., 1987, Cytogenet. Cell Genet. 46:636). Linkage studies in 11 families with NDI have enabled us to map the NDI gene between closely linked flanking markers in the Xq28 region and to obtain the following gene order: centromere-F9-DXS98-F8/CBD,CBP-DXS52/NDI-DXS134- telomere. These results have implications for presymptomatic and prenatal diagnosis of NDI and should also improve the prospects for identifying the fundamental gene defect underlying this disorder.

[The De Barsy syndrome]

De Barsy syndrome is defined by the combination of a progeroid aspect, cutis laxa, cornea clouding, growth retardation, mental retardation and athetoid movements. The clinical symptoms of a male infant are described and compared with all other cases reported in literature. The aetiology of this syndrome is unclear; inheritance is probably autosomal recessive.

Further analysis of the disturbed adrenocortical function in the cerebro-hepato-renal syndrome of Zellweger

Plasma aldosterone, corticosterone, 11-deoxycorticosterone, progesterone, 17-hydroxyprogesterone, 11-desoxycortisol, cortisol and cortisone were determined simultaneously in small plasma samples obtained during an i.v. ACTH (Synacthen) stimulation test in five patients (age 4-7 years) with Zellweger syndrome. The response of all ACTH-dependent steroids to Synacthen was severely impaired in all patients, despite normal basal levels. It can be concluded that the biochemical defect in adrenal steroidogenesis causing the inadequate response to ACTH injection is located proximal to progesterone. We propose that the lack of responsiveness to ACTH is secondary to an abnormality of ACTH receptors on the adrenocortical cell. The extremely low levels of non-specific lipid transfer protein may be a contributing factor.

Plasma concentrations of vitamin K1 and PIVKA-II in bottle-fed and breast-fed infants with and without vitamin K prophylaxis at birth

Plasma vitamin K1 and proteins induced by vitamin K absence (PIVKA) were assayed simultaneously 1-4 days and 29-35 days after delivery in three groups of infants: breast-fed not receiving vitamin K at birth (n = 12), bottle-fed without vitamin K administration at birth (n = 7) and breast-fed receiving 1 mg vitamin K1 administered by intramuscular injection at birth (n = 13). The bottle-fed infants had a significantly higher vitamin K1 plasma level than breast-fed infants who did not receive vitamin K1 at birth. Extremely high levels of vitamin K were obtained 1-4 days after intramuscular administration. At the age of 1 month, breast-fed infants had the same plasma vitamin K1 concentration whether or not they had received vitamin K1 supplements. Decarboxy prothrombin (PIVKA-II) a reliable indicator of biochemical vitamin K deficiency, was found in 5 out of 12 breast-fed and in 2 out of 6 bottle-fed infants who had not received supplemental vitamin K1 after birth. In a separate study, we followed up to 90 days after birth a larger group if infants. PIVKA-II was found with significantly greater frequency in breast-fed infants receiving no vitamin K than in breast-fed infants receiving 1 mg vitamin K intramuscularly at birth, or in bottle-fed infants without extra vitamin K1. These data form a strong argument for routine vitamin K prophylaxis after birth for all breast-fed infants. The optimum dose and manner of administration require further study.

Localization of the gene for X-linked Alport's syndrome

X-chromosomal DNA probes defining various polymorphic DNA markers were used to study genetic linkage in three families with Alport's syndrome. With the DXS17 marker, only a single cross-over was observed in 26 informative meioses, and evidence for linkage was also obtained with the DXS11 marker. These data localize the gene for the X-linked form of Alport's syndrome to the middle of the long arm of the X chromosome.

Nephrogenic diabetes insipidus: close linkage with markers from the distal long arm of the human X chromosome

Ten families with nephrogenic diabetes insipidus (NDI) have been analysed for restriction fragment length polymorphisms (RFLPs). A search for linkage was performed using various chromosome-specific single-copy DNA probes of known regional assignment to the human X chromosome. Close linkage was found between the disease locus and the markers DXS52, DXS15, DXS134 and the F8 gene. This result assigns the NDI gene to the subtelomeric region of the long arm of the X chromosome. The regional localization of the gene by the identification of closely linked markers should have repercussions for genetic counselling and prevention in NDI families.

Linkage of X-linked nephrogenic diabetes insipidus with DXS52, a polymorphic DNA marker

In five families with X-linked nephrogenic diabetes insipidus (NDI), linkage studies with the DNA marker DXS52, defined by probe St14, have shown no recombination with a maximum combined lod score of 6.40. These results assign the NDI gene to the subtelomeric region of the X chromosome long arm. This finding should facilitate identification of carriers and should also be helpful in finding the NDI gene itself.

Haemolytic-uraemic syndrome: a 10-year follow-up study of 73 patients

Long-term follow-up is presented of 73 patients suffering from the haemolytic-uraemic syndrome 10 years after the acute initial illness. The patients were subdivided into three groups, according to the criteria proposed by Gianantonio and based on the duration of oliguria and/or anuria. Four out of 38 patients belonging to the first group (oliguria for less than 7 days) had a slightly increased blood pressure as the only sequela. Two patients out of group two (n = 29, oliguria for 7-14 days or anuria for less than 7 days) had a diminished GFR and a reduced concentrating capacity, some proteinuria, and mild hypertension. Five other patients had slight proteinuria (less than 500 mg/24 h) and one of them a mild hypertension. All six patients belonging to the third group (oliguria for more than 14 days or anuria for more than 7 days) had late sequelae: two started haemodialysis more than 10 years after the initial phase; three have a decreased GFR and concentrating capacity. The unique remaining patient with a normal GFR without hypertension has a decreased concentrating capacity. The importance of careful treatment in children with a decreased GFR 2 years after the initial phase is stressed.

Infantile Refsum disease: an inherited peroxisomal disorder. Comparison with Zellweger syndrome and neonatal adrenoleukodystrophy

Three patients affected by infantile Refsum disease are described with mental retardation, minor facial dysmorphia, chorioretinopathy, sensorineural hearing deficit, hepatomegaly, failure to thrive and hypocholesterolaemia. Initially, only an accumulation of phytanic acid was thought to be present. More recent findings showed a biochemical profile very similar to that found in classical Zellweger syndrome or neonatal adrenoleukodystrophy. Morphologically typical peroxisomes were absent in the liver. All three disorders are associated with multiple peroxisomal dysfunction. Because of these similarities pertinent clinical data of our three patients are compared with those of reported patients diagnosed as having infantile Refsum disease, neonatal adrenoleukodystrophy or Zellweger syndrome who survived for several years. Attention is drawn to the difference in severity of clinical features, ranging from infantile Refsum's disease to neonatal adrenoleukodystrophy and, finally, to Zellweger syndrome.

The syndrome of hypertension and hyperkalaemia with normal glomerular function (Gordon's syndrome). A pathophysiological study

A 14-year-old boy with the syndrome of hypertension and hyperkalaemia with normal glomerular filtration rate (Gordon's syndrome) is described. The patient's clinical symptoms consisted of periodic paralysis, slight metabolic acidosis of the proximal type and hypercalciuria. Prostaglandin excretion was normal. Infusion of atrial natriuretic peptide had no effect on electrolyte excretion or glomerular function although a normal increase in cyclic guanosine monophosphate was demonstrated in plasma and urine. This lack of sensitivity to atrial natriuretic peptide offers a new pathophysiological concept in this syndrome. Treatment with hydrochlorothiazide was successful in this case.

[Neonatal ascites caused by urine leakage]

Two neonates, born with an extremely distended abdomen due to ascites, are described. A leakage of urine, secondary to urinary tract obstruction by urethral valves, was the cause of peritoneal fluid accumulation. Analysis of the peritoneal fluid is an important step in differential diagnosis, because only in ascites of urinary origin the creatinine- and ureaconcentrations exceed those of plasma. Treatment consists of temporary urinary diversion followed by operative relief of the obstruction.

Peroxisomal disorders: clinical characterization

The peroxisomal disorders can be divided into three classes: firstly, those in which the activity of only one single enzyme is reduced; secondly, those in which the activities of multiple peroxisomal enzymes are deficient and also the number of peroxisomes is reduced; and thirdly, those in which the activities of multiple peroxisomal enzymes are lacking and at the same time the number of peroxisomes is normal at least in liver tissue. The cerebro-hepato-renal syndrome of Zellweger is the prototype of peroxisomal disorders of the second group. Clinical distinction between Zellweger syndrome and neonatal adrenoleukodystrophy or infantile Refsum disease can be impossible. The clinical abnormalities that should give rise to suspicion for the presence of a peroxisomal disorder and urge the necessity of further biochemical studies are proposed.

Renovascular hypertension in a child with Degos-Köhlmeier disease

A 7-year old boy with Degos-Köhlmeier disease developed renovascular hypertension. Arteriography showed peripheral occlusive arteriopathy of the left kidney as part of the Degos-Köhlmeier disease.

Protein C levels in infancy and early childhood. Influence of breast feeding

Protein C antigen levels were measured in the plasma of healthy full term infants by electroimmunoassay. During the first three months of life (on day four, at one month, two months and three months of age) protein C antigen levels were compared in breast-fed and bottle-fed infants. None of the two groups of infants received vitamin K at birth. Only at the age of three months there was a significant difference between the groups. Unexpectedly infants, who were breast-fed, had a higher protein C level at three months of age. Levels were also measured in 15 healthy children between one and three years of age. The antigen levels increase with age to reach adult values at about three years of age.

[Type III osteogenesis imperfecta associated with hypophosphatemic vitamin D-resistant rickets]

In a 7 year old girl presenting with bone deformities, dwarfism, and a history of recurrent fractures osteogenesis imperfecta had been diagnosed at birth. Although she had been hospitalized several times, radiologic signs of rickets remained unnoticed. Laboratory data proved existence of hypophosphatemic vitamin D-resistant type of rickets, which was effectively treated with 1 alpha-hydroxycholecalciferol and phosphorus substitution. The combination of osteogenesis imperfecta type III and hypophosphatemic rickets may be coincident. It proves, however, the necessity to consider the possible simultaneous occurrence of two rare diseases. The therapeutic consequences could be important.