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Biomedical subjects

G Hirbec

Publications and source records attributed to G Hirbec.

At least 19 recordsLinked to original sources

[Lipoid nephrosis of toxic origin. 2 cases].

Classically, the histological lesion observed in a drug-or heavy metal-induced nephrotic syndrome is membranous glomerulonephritis. We report two cases of "toxic" nephrotic syndrome with unusual histological features. One was secondary to mercury intoxication and the other, to D-penicillamine in a patient with rheumatoid arthritis. In both cases, renal biopsy revealed minimal glomerular changes. The proteinuria rapidly disappeared after exposure to the toxic agent was discontinued. Genetic factors and a disregulation of the immune system with lymphokine production may be responsible for these renal changes. This study demonstrates that renal biopsy is necessary in this clinical setting.

Adult

Coincidence of familial systemic lupus erythematosus and the fragile X syndrome.

The coincidence of fragile X syndrome (fra(X] and systemic lupus erythematosus (SLE) in the same family is reported here for the first time. A 16-year-old boy with typical fra(X) had a severe SLE with multiple organ involvement. His 12-year-old sister of normal intelligence had circulating antinuclear antibodies and proliferative glomerulonephritis. The fra(X) was not found in her karyotype. Except for abnormalities due to immunosuppressive treatment during pregnancy, the association of SLE and chromosome abnormalities has been only reported in Klinefelter's syndrome. The possible pathogenic role of sex hormonal abnormalities due to an extra X chromosome has been suggested in the occurrence of SLE.

Fragile X Syndrome

Focal glomerulosclerosis associated with Charcot-Marie-Tooth disease.

This report describes a new case of the rare association of focal glomerulosclerosis with a peroneal muscular atrophy of the Charcot-Marie-Tooth type. The young patient was admitted with a nephrotic syndrome. A terminal renal failure rapidly developed. Numerous chronic nephropathies were known in the patient's family. The ultrastructural study of the renal biopsy revealed a focal fusion of the epithelial foot processes, thickened and pleated mesangial basal laminae, vacuolated podocytes and small intranuclear clear inclusions. The Charcot-Marie-Tooth disease was of the hypertrophic type. According to a review of the literature and to further information concerning the follow-up of the 5 previously reported cases, the prognosis of the nephropathy is guarded with progression to end-stage renal disease in a few years. This case represents the 6th reported case of focal glomerulosclerosis associated with Charcot-Marie-Tooth disease.

Adolescent

Intraglomerular metastases. Report of two cases.

Glomerular metastases are rarely observed. Two cases of such metastases are reported. In one patient, proteinuria was detected and the diagnosis was made by kidney needle biopsy; light microscopy, immunofluorescence, and electron microscopy studies were performed. The second case was an autopsy finding. The histologic patterns were, respectively, an intracapillary metastasis and associated intra- and extracapillary metastases. These findings raise a number of questions concerning the early detection of such neoplastic diseases, the nature of primary tumors, and the mechanisms of malignant dissemination and glomerular localization.

Autopsy

[Incorporation of L-azetidine-2-carboxylic acid into collagen of the skin. Structural changes].

As previously shown by two dimensional thin-layer chromatography L-azetidine-2-carboxylic-acid (L-Az) is incorporated into type I skin collagen instead of proline when 3 week old mice are fed with a 0,1% solution of L-Az orally. Ultrastructural investigations did not reveal significant changes in collagen periodicity and on fibril diameter. The collagen fibrils of the upper papillary dermis seemed to be packed more densely, sometimes only one electron dense lamina was seen instead of basal lamina and plasma membrane. The glycosaminoglycane-induced fibrillogenesis was not changed in contrary to the collagen-heat-gelation fibrillogenesis at 37 degrees C, where no gel aggregation could be seen. The reconstruction of native fibres from collagen solutions was disturbed too, several finer precipitated fibrils being detectable. On infrared spectroscopy significant differences in absorption spectra were detected. Correlating with previous results of reduced tensile strength and normal melting point of L-Az collagen we can conclude that L-Az might cause rather intermolecular than intramolecular disturbances of crosslinking.

Animals

Is house dust allergen a possible causal factor for relapses in lipoid nephrosis?

In three cases of minimal change nephrotic syndrome (lipoid nephrosis), an allergen sensitivity to house dust, cat hair and grass pollen was demonstrated by clinical and biological data. An increase in proteinuria after specific allergen contact and a decrease after withdrawal of the allergens, suggested that the cause was allergenic. Such cases demonstrate the necessity of an etiological investigation of particularly the atopic features in lipoid nephrosis. Results of these investigations can lead to specific therapy in selected cases.

Adolescent

Serum IgE in primary glomerular diseases.

Serum IgE was measured by RIST test in 181 adult subjects, with log transformation. In 24 controls the geometric mean was 109 IU/ml, with an upper limit (geometric mean +/- 2 SD) of 460 IU/ml. 157 cases of glomerulonephritis (GN) classified according to light and immunofluorescence microscopy were studied. Serum IgE was significantly elevated in 39 lipoid nephrosis patients (p less than 0.001, with 21 levels greater than 460 IU/ml), 21 focal and segmental glomerulosclerosis (p less than 0.05, with 8 levels greater than 460 IU/ml) and 42 membranous GN (p less than 0.01, with 10 levels greater than 460 IU/ml). In 27 membrano-proliferative GN and 28 IgA GN, serum IgE was not different from controls with respectively 4 and 3 levels greater than 460 IU/ml. In addition, the lipoid nephrosis IgE geometric mean is 493 IU/ml, which is keeping with the high incidence of atopic troubles. The significance of raised serum IgE was discussed.

Adolescent

Silent lupus nephritis among patients with discoid lupus erythematosus.

A kidney biopsy was performed in 7 hypocomplementemic discoid lupus erythematosus patients despite the absence of overt renal involvement. Five patients had glomerular immune deposits and 2 patients with disseminated discoid lupus erythematosus exhibited definite proliferative glomerulonephritis. Those findings show that silent lupus nephritis may be encountered in discoid as well as in systemic lupus erythematosus, providing additional evidence supporting the unity of the disease. We suggest that hypocomplementemic patients with discoid lupus erythematosus must be carefully screened for renal disease by periodic urinalysis examinations.

Complement C3

[Biological study of spontaneous amyloidosis in PS mice].

A remarkably severe spontaneous amyloidosis involving multiple organs has characterized the inbred PS mouse strain since the 25th generation. The amyloid substance was extracted with H2O and purified by successive gel filtrations on Sephadex G100, Sephadex G10 and Biogel P4. It was submitted to biochemical, immunochemical and histochemical analysis in order to determine its origin. Potassium permanganate resistance of the affinity for Congo Red dye, aminoacid composition, cross-reactivity with anti-mouse light chains antisera suggested an amyloidogenic process comparable to that described for the AL substance in man. However, even if abnormal lymphoid infiltrates were present in several organs, the presence of M component could not be demonstrated in serum or urine of these mice. This indicated either a limited tumoral mass or a tumor poorly secreting a precursor that would be strongly amyloidogenic. Alternatively, the existence of a so far unidentified precursor could not be excluded.

Amyloid

[Frequent positivity of the human basophil degranulation test in idiopathic nephrotic syndromes (minimal glomerular changes and segmental and focal glomerulosclerosis)].

Atopic factors play an important role in minimal changes idiopathic nephrotic syndrome ( MCINS ). We therefore studied human basophil degranulation test ( HBDT ) in MCINS and also in patients with segmental and focal glomerulosclerosis ( SFGSNS ) whose relation with MCINS is debated. HBDT was performed with 5 or 6 allergens chosen according to the history of patients and results of cutaneous tests. HBDT was positive in 16 out of 28 MCINS and in 14 among 18 SFGSNS subjects. The difference versus 29 Immune Complex glomerulonephritis and 11 blood donors was significant with the chi 2 test. Because the basophil count was low (less than 10/microliter) in 5 cases, 4 of which had a severe nephrotic syndrome, the HBDT was performed later. The allergen most frequently involved was house dust. This was responsible for a significant degranulation in 10 MCINS (45%) and in 11 SFGSNS (68%) patients; degranulation was obtained more frequently with 2 allergens than with a single one. Obviously such a basophil sensitisation does not prove the responsibility of these allergens.

Adolescent

Studies on the alpha-glucosidase specific for collagen disaccharide units: variations associated with capillary basement membrane thickening in kidney and brain of diabetic and aged rats.

The alpha-glucosidase specific for the hydroxylysine-linked disaccharide units of collagens (or 2-0-alpha-D-glucopyranosyl-5-0-beta-D-galactopyranosylhydroxy-L-lysine glucohydrolase) has been measured in kidney cortex and brain cortical tissue of streptozotocin diabetic rats after 19, 23 or 28 weeks of diabetes and of aged rats 22 months old. Increased specific activities of the enzyme have been found repeatedly in the dialyzed homogenates and the 7.2 X 10(6) g.min supernatants of kidney and brain at the various stages of diabetes when compared with age-matched controls; the specific activities returned to a normal level after insulin treatment. Similar increased specific activities were observed in kidney and brain of the aged normoglycemic rats when compared with young adult rats. In diabetic kidney cortex, beta-galactosidase and p-nitrophenyl-alpha-D-glucoside glucosidase specific activities were decreased in contrast to the increase of glucosyl-galactosyl-hydroxy-lysine glucohydrolase. In kidney cortex of the aged rats, beta-galactosidase activity was also decreased, but p-nitrophenyl-alpha-D-glucoside glucosidase was increased. In both diabetic and aged rats, thickening of the kidney glomerular basement membranes was confirmed; thickening of the brain cortical capillary basement membranes was also observed. Thus in the diabetic and aged animals, the increased glucosyl-galactosyl-hydroxylysine glucohydrolase specific activity was associated with basement membrane thickening in the kidney and the brain.

Aging

[Phagocytic activity of monocytes in human primary glomerulonephritis].

Circulating immune complexes (CIC) account for a majority of GN. Their pathogenicity depends on size, molecular composition, glomerular hemodynamics and activity of phagocytes. The phagocytic function of peripheral monocytes was studied in 23 patients with nonsystemic GN. Phagocytic activity of peripheral blood monocytes was assessed in vitro, by calculating phagocytic index (IP: number of zymozan particles in each monocyte) and phagocytosis percentage (PP: number of phagocyting monocytes); the tests were carried out on autologous and heterologous serum samples. In 13 controls, PP was 79 +/- 5.8%. In 7 membranous GN, 6 membranoproliferative GN and 10 lipoid nephrosis, PP was severely decreased, 63.4 +/- 9.6%, 52.1 +/- 19% and 52.2 +/- 14%. In each group of GN, these results were significantly different from controls (p less than 0.01). In all groups these results were similar in autologous and heterologous serum samples (55 +/- 13% and 57.5 +/- 16%; NS). Therefore, this defect was not linked to the presence of serum inhibitors. In conclusion, alterations of phagocytic activity is present in some primary GN and may explain an insufficient rate of CIC removal.

Glomerulonephritis

Nephrotic syndrome associated with T-cell lymphoma.

Glomerulopathies associated with non-Hodgkin's malignant lymphomas have been observed rarely. Previous reports have never determined the cell type of the lymphoproliferative disorder. This report documents a case of nephrotic syndrome in a patient with T-cell derived non-Hodgkin's lymphoma. The neoplastic cell was studied in terms of cell-surface markers, cytochemical staining, and ultrastructural morphology. Nephrotic syndrome occurred shortly after the apparent onset of the lymphoma. The kidney biopsy specimen was examined by light, fluorescence, and electron microscopy. Histologic findings were consistent with the diagnosis of mild focal and segmental glomerulosclerosis. Such an association, reported here for the first time, may support the hypothesis of a pathogenetic link between acquired T-cell abnormalities and glomerular diseases with minimal histologic injury.

Adolescent

Hereditary C2 deficiency associated with non-systemic glomerulonephritis.

A patient with non-systemic idiopathic glomerulonephritis was found to have a complete deficiency of C2, the second component of complement. The clinical course, histological findings and serological abnormalities are reported in detail. The renal disease was a mild glomerulonephritis with mesangial and subendothelial immune deposits comprising IgG, IgM and C3, increased mesangial matrix without significant cell proliferation. An immunogenetic analysis of the patient's family was carried out. It was demonstrated that the homozygous C2 deficiency was associated with heterozygotism for HLA-A, B and D. Only one of the C2 deficient genes was associated with the expected HLA-A10, B18 haplotype and the propositus was HLA-D2 negative. This report confirms the fact that non-systemic glomerulonephritis should be included in the variety of immunological disorders associated with a complement deficient state. However, C2 deficiency does not seem to be related specifically to a given histological variety of glomerulonephritis.

Adult