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Biomedical subjects

S Olsen

Publications and source records attributed to S Olsen.

At least 127 records · Page 7Linked to original sources
PubMed1981

The prevalence of focal tubulo-interstitial lesions in various renal diseases.

The focal tubulo-interstitial lesions (FTIL) described in the present paper appear as short segments of tubules showing epithelial degeneration, necrosis and desquamation. The foci are surrounded by mononuclear cells, among which lymphocytes are most numerous. They infiltrate through the damaged tubular basement membranes and may thus be located between epithelial cells and in the tubular lumen. Older lesions show focal tubular atrophy with thickened basement membranes together with focal interstitial fibrosis and lymphocytic infiltrates. The overall prevalence of this type of lesion in a consecutive renal biopsy series was 36%. It was not detected in 24 biopsies from patients without renal disease. The frequency of FTIL was high in acute renal failure due to hemolysis, shock etc. or to the action of drugs, as well as in some types of glomerulonephritis (membranous, membrano-proliferative, SLE). Tubular immunoglobulins were not demonstrated in 38 biopsies with FTIL. The pathogenesis and possible consequence of the lesions are still unclear, but it is suggested that they may in some situations contribute to the nephron atrophy in chronic renal disease.

Atrophy↗
PubMed1981

Circulating immune complexes in glomerulonephritis.

The relationship between the presence of circulating immune complexes (CIC), clinical features and renal histology was investigated at the time of renal biopsy in 77 patients with glomerulonephritis. The glomerulonephritides were classified primarily according to light microscopic criteria and later using light microscopy combined with electron microscopy and immunofluorescence. Three methods for detection of CIC were used: C1q-binding-activity, anticomplementary activity and a PEG-precipitation test. When two of the three methods were positive, CIC were regarded as being present. CIC were detected most frequently in patients with "hump-nephritis" (5/6), extracapillary glomerulonephritis (6/7) and lupus-nephritis (7/8), and only rarely in patients with membranous glomerulonephritis (0/7), IgA-nephritis (1/13) and minimal change disease (1/5). A weak correlation was observed between the presence of CIC and the presence of glomerular deposits of IgG +/- IgM detected by immunofluorescence, but no correlation with the presence of electron dense deposits was seen. CIC were detected significantly more often in patients with recent onset of renal disease and in patients with antecedent infections. No correlation could be demonstrated between CIC and renal function, proteinuria, hematuria, blood pressure or progression of renal failure. Serial measurements of CIC in 6 patients with glomerulonephritis showed that CIC may be present transiently and not always be related to the activity of disease.

Adolescent↗
PubMed1981

Quantitative relationship between glomerular foot process width and proteinuria in glomerulonephritis.

The relationship between foot process fusion (retraction) and proteinuria in glomerular diseases has been known for many years, but only a few quantitative studies have been performed. The quantitative morphometrical method used here makes it possible to estimate the distribution of true foot process width from the observed apparent width on electron micrographs. The true foot process width was analyzed in a consecutive material of patients with glomerulonephritis and related to the diurnal urinary protein excretion. Only a weak correlation was found between these two parameters. Albeit an abnormal foot process width was invariably associated with proteinuria, a rather large fraction of patients with gross proteinuria had normal foot process width compared to control subjects. Thus, if foot process fusion causes proteinuria, this can not be the only mechanism leading to this permeability alteration. On the other hand, our results show that foot process fusion is not a necessary consequence of proteinuria. In addition, a methodologic study was performed, analyzing the relationship between the quantitative and a semiquantitative method for estimating foot process fusion. It is concluded that the latter method is fast and sufficiently precise for most evaluations of foot process width in human kidney biopsies.

Biopsy↗
PubMed1980

Cortical interstitial tissue and sclerosed glomeruli in the normal human kidney, related to age and sex. A quantitative study.

The relative amount of interstitial cortical tissue was measured by the point count method in kidney tissue from human individuals without renal disease. One series (54 kidneys) consisted of kidneys intended for transplantation and removed immediately after death from persons who died suddenly. The other series (69 kidneys) was obtained by autopsy. In both groups, the percentage of interstitial tissue was dependent on age and followed the equations of regression (1) y = 12.45 + 0.11 0.11 x (donor series) and (2) y = 23.8 + 0,10 x (autopsy series). The autopsy values were significantly greater than the donor-kidney-values. There was no difference due to sex. The relative number of sclerotic, obsolescent glomeruli was very small (0-1%) until the age of 40. Thereafter it increased, most markedly in the autopsy series, until it reached values of about 30% in persons more than 80 years old.

Adolescent↗
PubMed1980

The predictive value of percutaneous biopsies from human renal allografts with early impaired function.

A semiquantitative histological analysis was performed on 84 percutaneous biopsies 0-60 days post transplant from 66 grafts with clinical rejection, decreasing graft function of unknown etiology or persisting anuria. The presence of 1 or more of 3 histological lesions was associated with 100% graft loss within 1 year. The lesions were: infarction, glomerular capillary thrombosis, and arterial/arteriolar thrombosis. Since the detection of these severe lesions only permitted prediction of an unfavourable course in 72% of all grafts that were subsequently lost, a system was elaborated utilizing the sum of scores of 12 histological and 4 clinical parameters. This system failed to improve the prognostic value of the biopsy since diagnostic specificity as well as sensitivity was slightly lower by this method. The conclusion is that a graft biopsy performed during early graft failure has a high predictive value for graft loss if infarction, arterial thrombosis or glomerular capillary thrombosis is present; however the predictive value of a negative test is low.

Adolescent↗
PubMed1979

Evaluation of a procedure for systematic semiquantitative analysis of glomerular ultrastructure in human renal biopsies.

A method is described for systematic semiquantitative investigation of glomerular ultrastructure in renal biopsies from patients with glomerulonephritis. Three glomeruli per biopsy were studied by electron microscopy. Ten systematically recorded micrographs at x12,000 and a montage covering the whole glomerular cross-section at x3,000 were analyzed from each glomerulus. The severity of each of 34 different ultrastructural lesions was semiquantitatively evaluated on a 4-degree scale, 0 to +++. The usefulness of the method was evaluated by calculating different parameters for the reproducibility of semiquantitative scoring, representativeness of micrographs, and representativeness of glomeruli. The reliability of the method was considered good or acceptable with respect to 17 of the lesions. Ten lesions obtained a high reproducibility of scoring but the usefulness of the scores was limited due to a segmental and/or focal distribution of these lesions. The evaluation of these lesions can be improved by analyzing a larger number of micrographs, or glomeruli, or both. Seven lesions were so rare in the present biopsies that no statistical evaluation was possible. When applied to a large number of biopsies, this practical and useful method allows a reproducible comparison of the patterns of ultrastructural lesions in various types of glomerulonephritis.

Basement Membrane↗
PubMed1978

Circulating immune complexes in syphilitic nephropathy. A case report.

A case of transient nephrotic syndrome caused by secondary syphilis is described. A renal biopsy was performed revealing subepithelial hump-like electron-dense deposits and fusion of epithelial foot-processes. Complement C1q-binding-activity and anticomplementarity were demonstrated in the blood, indicating the presence of circulating immune complexes. This strongly suggests that circulating immune complexes are significant in the immunopathogenesis of syphilitic nephropathy.

Adult↗
PubMed1977

A quantitative study of glomeruli in idiopathic nephrosis with minimal or no glomerular lesions.

A quantitative investigation was performed of glomeruli in renal ibiopsies from patients with nephrotic syndrome or persisting proteinuria associated with normal light microscopic findings or slight changes not considered significant ("minimal change disease", lipoid nephrosis). The mesangial area was widened (+ 26 per cent, p less than 0.05) and there was an increase in the mean of the total number of cellular nuclei per glomerulus, the number of mesangial (+ 16 per cent) and edothelial nuclei (+ 23 per cent), but of these only endothelial hypercellularity was significant (p less than 0.025).

Adolescent↗