Chronic hereditary nephritis. A clinicopathologic study of 23 new kindreds and review of the literature

Familial glomerulopathy with proximal tubular dysfunction: a new syndrome?

Two female siblings with nephrotic syndrome and proximal tubular dysfunction are described. One, aged 15 months, presented with steroid-resistant nephrotic syndrome and was found to have partial Fanconi syndrome and hypothyroidism. At the age of 21 months her renal function started deteriorating rapidly and she died of septicaemia 5 months later. The second sibling, aged 3 years, had steroid-resistant nephrotic syndrome with proximal renal tubular acidosis and hyperaminoaciduria. The renal biopsies in both showed unusual changes in glomerular basement membrane along with IgM and C3 deposition. It is suggested that these siblings may be suffering from a hitherto undescribed clinico-pathological entity.

Alport's syndrome

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Alport's syndrome as a cause of renal failure in Europe

We studied the geographical distribution, male to female ratio, and age at the start of renal replacement therapy (RRT) for end-stage renal failure (ESRF) in 600 patients with hereditary nephritis with nerve deafness (Alport's syndrome) reported to the European Dialysis and Transplant Association Registry since 1975. Annual age- and sex-specific acceptance rates for RRT showed a variable peak incidence according to country, ranging between, 0 and 2.4 patients per million population in males aged 15-24 years, but with only about half this incidence in females. In Scandinavian countries there were very few females who started RRT, and males were older than in the rest of Europe. The overall male to female ratio was 4:1. The median age at the start of RRT was: males (n = 479) 24.3 years (1st quartile 19.5 years; 3rd quartile 31.5 years); females (n = 121) 31.5 years (1st quartile 23.0 years; 3rd quartile 43.2 years). Our study provided confirmation that males reach ESRF earlier than females. In addition, we detected previously unrecognized geographical differences.

Isolated hematuria in children: indications for a renal biopsy

Previous reviews of hematuria in children and adolescents have included patients with proteinuria and other renal functional abnormalities such as hypertension and reduced GFR. We report the clinico-pathological correlations in 76 pediatric patients, aged 3 to 19 years, who underwent a renal biopsy because of isolated hematuria during the 10-year period, 1972 to 1981. All specimens were examined by light and electron microscopy and immunofluorescence techniques. The overall prevalence of abnormal renal histology was 56%. The vast majority (41 of 43) of the abnormal biopsy specimens could be classified into four distinct histological categories: (1) Alport syndrome (N = 9); (2) IgA nephropathy (N = 8); (3) thinning of the glomerular basement membrane (N = 17); (4) vascular C3 staining (N = 7). The children were divided into three clinical subgroups (1) isolated microscopic hematuria ( IMH ), N = 42; (2) IMH plus a family history of hematuria in a first degree relative, N = 15; and (3) IMH plus at least one episode of gross hematuria, N = 19. A significant graded increase in the likelihood of obtaining an abnormal renal biopsy was demonstrated (X2 = 10, P less than 0.007) from groups one to three. Sex, age at onset, or duration of hematuria were not associated with an increased proportion of histopathologic abnormalities. These findings indicate that the yield of a renal biopsy in children with isolated hematuria can be predicted accurately from specific clinical characteristics.

Glomerular basement membrane attenuation in familial nephritis and "benign" hematuria

Lamination of the basement membrane has been considered to be the lesion characteristic of familial nephritis and attenuation to be the lesion of "Benign" familial hematuria. Electron micrographs were reviewed of 57 children who had renal biopsies for persistent hematuria. Attenuation or lamination of the glomerular capillary basement membrane was found in each. Twenty of the 57 children had familial nephritis; 20 had familial hematuria; and 17 had no involved relatives. Follow-up data were available for 14 of 20 children with familial nephritis, 12 of 20 with familial hematuria, and 12 of 17 with sporadic hematuria for 13.6 +/- 6.3, 6.7 +/- 4.6, and 7.0 +/- 4.8 years, respectively, after discovery of hematuria. Five children developed end-stage renal disease: three with familial nephritis, one with familial hematuria, and one with sporadic hematuria. Only two no longer had hematuria. Attenuation of the glomerular capillary basement membrane was seen in every biopsy, whereas lamination was not. Because hematuria and ultrastructural abnormalities were findings shared by all the children, we suggest the possibility that familial nephritis, and familial or sporadic hematuria as defined in this study, may be variations in a spectrum of inherited abnormality or abnormalities in the formation of the glomerular capillary basement membrane.

The glomerular basal lamina in hereditary nephritis

Characteristic ultrastructural alterations of the glomerular basal lamina have been reported in hereditary nephritis. The basal lamina is irregularly thickened and the lamina densa shows replication with a "basket weave" pattern, enclosing electron-lucent lacunae which frequently contain small dense particles. However there is controversy regarding the specificity of this lesion in hereditary nephritis. To determine the specificity, 366 renal biopsies from 310 children were studied retrospectively. Twenty-four out of 27 patients with hereditary nephritis showed the characteristic changes of the basal lamina and they were widespread in 17. Two patients with recurrent haematuria but no family history of deafness or haematuria showed similar extensive changes and are regarded as new mutant cases of hereditary nephritis. Similar changes were seen in 17 of the 281 patients with other conditions but were always localized to a few capillary loops. We conclude that a widespread "basket weave" pattern appears to be confined to hereditary nephritis and is seen in the great majority of such cases.