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SummaryTotal serum cholesterol, phospholipids, and triglyceride levels, lipoprotein fractionation, and plasma parathormone levels were measured in a group of 31 nonnephrotic children with various levels of renal function and on hemodialysis. Group A served as controls and consisted of eight healthy children with glomerular fdtration rate (GFR) greater than 110 ml/min/1.73 m2. Group B consisted of six children with GFR of 60 to 95 ml/min/1.73 m2. Group C consisted of nine children with GFR of 10 to 40 ml/min/ 1.73 m2, and group D consisted of eight children on maintenance hemodialysis with GFR of 0 to 5 ml/min/1.73 m2. Among the groups, there were no significant differences in total serum cholesterol and phospholipid levels. A significant ( P < 0.05) increase in triglyceride levels was observed in patient groups C and D.Lipoprotein fractionation revealed a significant increase (P < 0.05) in the pre-beta lipoprotein levels (very low density lipoproteins) in patients in group D with 63% of these patients demonstrating a type IV lipoprotein pattern. There were no significant differences observed in the beta lipoproteins (low-density lipoproteins). However, the alpha lipoproteins (high-density lipoproteins) decreased significantly ( P < 0.05) in patients whose GFR was below 40 ml/min/1.73 m2 (group C) as well as patients in group D.Absolute plasma parathormone levels did not significantly correlate with serum triglyceride levels and remained normal until after the onset of hemodialysis when they increased significantly in all patients. SpeculationEvidence has been accumulating over the past few years that chronic hemodialysis and renal transplant adult patients have shortened survival because of accelerated atherosclerotic cardiovascular disease for which hyperlipidemia could be one of several etiologic factors. Similar epidemiologic studies have not been performed in children. We have demonstrated for the first time in children that alterations in serum triglycerides and alpha lipoproteins (high-density lipoproteins) occur early in chronic renal insufficiency and before the onset of uremia when the glomerular fdtration rate falls below 40 ml/min/1.73 m2. These lipid abnormalities become further aggravated with the onset of hemodialysis. If pediatric renal transplant patients show similar lipid abnormalities, then the potential for cardiovascular complications will be of importance in the early medical management of these children.

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SummaryHereditary nephritis (HN) is a progressive renal disease not uncommonly seen in children. Asymptomatic hematuria is an early and consistent finding'with or without proteinuria. Distinctive abnormalities frequently associated with this condition involve basement membranes primarily (glomerular basement membrane, lens capsule, and possibly, tectorial membrane of the organ of Corti). These basement membranes contain collagen with similar biochemical composition suggesting that this association may be pathogenetically related. On the basis of this observation, we studied collagen metabolism in patients with HN by utilizing urinary hydroxylysine glycosides (hyl glyc) as an index of collagen metabolism. The hyl glyc hydroxylysine galactose glucose and hydroxylysine are basic units in basement membrane as well as a large number of other collagen. We studied 25 normal children, seven patients with HN, and six HN siblings with hematuria. The mean excretion of total hyl glyc are 64 + 5.5,93 + 14, and 123 +. 15.6 umoles/g creatinine, respectively. The difference in the mean excretion level of total hyl glyc between patients with HN and normal controls is statistically different (P < 0.05).The siblings of HN patients differed significantly from normal (P > 0.005), but was comparable to the HN patients. Two of 16 additional patients studied had the Nail Patella syndrome and showed increased urinary hyl glyc. The elevated urinary hyl glyc in HN patients and their siblings strongly suggests an altered rate of collagen degradation during the natural course of the disease. The origin of collagen is presently unknown because no data exists describing the biochemical composition of basement membrane collagen in HN. To elucidate further the pathogenesis of this important disease, studies should investigate the biosynthesis and metabolism of basement membrane collagen of involved structures.sibly, tectorial membrane of the organ of Corti). Collagen recently shown to be present in these basement membranes have very similar biochemical composition (10). Collagen changes have been reported in the organ of Corti in HN. (12).On the basis of these observations we studied collagen metabolism in patients with HN by measuring urinary hydroxylysine glycosides. The hyl glyc are hydroxylysyl galactose glucose (HGG) and hydroxylysyl galactose (HG). These two glycosides are basic units in basement membrane collagen as well as a large number of other collagens. They are metabolized only to a minor degree before excretion and have a high threshold of clearance. MATERIALS AND METHODSEarly morning specimens were collected and stored without preservative at -70°C pending analysis. Informed consent for the study was obtained from the parents. Seven patients (M-4, F-3) ages 6-13 with HN were studied. All patients had positive family and clinical history. Two of four affected males were brothers with neurosensory hearing loss and were both azotemic. One girl was uremic without hearing loss at the time of the study. No other abnormalities were obse...

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ExtractThe accumulation of literature on hereditary nephritis with or without nerve deafness attests to the increased awareness of the existence of this syndrome. I t is the purpose of this report to show that there are distinguishing histologic findings in young patients with minimal disease and normal renal function. Eleven patients were studied; 4 were females and 7 were males. Relevant family histories and clinical laboratory findings are shown in table I. I n all patients, hematuria, gross or microscopic, was present. Exacerbations of the hematuria occurred as a part of the exaggerated response of these patients to upper respiratory infection. Renal functional data are shown in table 11. These data were generally within normal limits for our laboratory. Table I11 outlines the morphologic findings observed on renal biopsy. In renal biopsies obtained from 10 patients, there was observed persistence of fetal-like glomeruli characterized by the circumferential crowding of visceral epithelium and an apparent decrease in the number of patent capillaries. The most striking finding in the tubules was the presence of red cells and red blood cell casts seen mainly in the distal and collecting tubules. Foam cells were an infrequent finding but, when present, were unassociated with interstitial fibrosis. Examination of kidney specimens under the electron microscope revealed the presence of at least three glomeruli in seven patients and of fetal-like glomeruli in all patients. There was also circumferential crowding of visceral epithelial cells, particularly at the surface, facing Bowman's capsule. These epithelial cells were characterized by large nuclei, small amounts of cytoplasm, apparently poorly developed intracytoplasmic organelles, and frequent villous-like cytoplasmic projections on the surface. I n families from whom past histories are unavailable, recognition of distinct renal biopsy characteristics would help identify this syndrome in the early stages of disease. At this stage, the combination of morphologic features considered to be characteristic would include the presence of a) fetal-like glomeruli, which were seen by electron microscopy in 7 patients and by light microscopy in 10 patients; b) mild to moderate hypercellularity ; c) large numbers of tubules filled with red blood cells and red blood cell casts; and d) foam cells in the absence of interstitial fibrosis. The fetal-like glomeruli present in our patients did not correspond to any of the normal stages of glomerular development observed under electron microscopy by other investigators, but rather, appeared to represent dysgenesis. Most patients from whom data are reported were more than 2 years of age, at which time fetal glomeruli are exceptional. Of interest was the observation that almost identical histology was found to exist among the siblings. ANTONOVYCH, DEASY, TINA, D'ALBORA, HOLLERMAN a n d CALCAGNO SpeculationT h e fetal-like glomeruli observed o n renal biopsy might b e the result of either a developmental abnormality or dysgenesis. T ...

The initial renal sonograms of 15 patients, aged 8 months to 5 years, with hemolytic uremic syndrome (HUS) were reviewed. Ultrasound studies were graded according to cortical echogenicity relative to the liver, they were compared to the severity of the clinical syndrome at admission and to the ultimate outcome of the disease. The degree of cortical echogenicity correlated with the clinical outcome of HUS in 12 of the patients, whereas clinical assessment alone predicted outcome in 13 patients. Sonography overestimated severity in three patients with mild disease correctly assessed clinically, whereas clinical assessment overestimated severity in two patients with moderate disease in whom the sonographic assessment proved correct. The sonographic changes are most likely multifactorial. They appear to reflect a combination of platelet-thrombus deposition in the renal cortex, as well as the general fluid status of the patient. Ultrasound is useful in ruling out other causes of acute renal failure such as obstruction or congenital diseases. It cannot replace laboratory tests and clinical judgement, but nevertheless provides another index of severity in patients with HUS.