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R Waldherr

Publications and source records attributed to R Waldherr.

At least 163 records · Page 9Linked to original sources
PubMed1989

[Expression of class I and class II histocompatibility antigens in inflammatory kidney diseases].

MHC class I and II molecules serve as restriction elements for the presentation of antigen-specific T cell reactions and may be implicated in the process of cellular transformation. We have analysed the expression of MHC class I and II antigens including the associated invariant gamma-chain in 100 consecutive renal biopsies by a sensitive immunoperoxidase method using monoclonal antibodies against HLA-ABC, HLA-DR, HLA-DQ, HLA-DP and the invariant gamma-chain (Ii). HLA-ABC was expressed by almost all parenchymal cells except for podocytes. Staining for HLA-DR was found consistently in glomerular and interstitial capillary endothelial cells, in "dendritic" (LCA positive) and most infiltrating interstitial cells but not in mesangial and most extracapillary cells. Similar but weaker positivity was observed for HLA-DQ and -DP. HLA-DR positive infiltrating mononuclear cells in glomeruli were noted in acute glomerulonephritis (GN) and Lupus GN associated with enhanced staining of endothelial cells. In addition, HLA-DR was uniformly or focally expressed by predominantly proximal tubules in 80% of biopsies, especially IgA-GN, focal glomerulosclerosis, acute GN but also in 54% of cases with minimal change nephrosis. HLA-DP and -DQ were only positive in a limited number of HLA-DR positive tubules. The expression of the invariant gamma-chain was comparable with the reactivity for HLA-DR. In addition, all HLA-DR-positive tubules expressed the invariant gamma-chain. Subtyping of T cells in biopsies with DR-positive tubules and interstitial infiltrates (n = 20) showed a predominance of CD 4 positive cells in the majority of cases.(ABSTRACT TRUNCATED AT 250 WORDS)

Glomerulonephritis↗
PubMed1989

[Immunogenetics of mesangial IgA glomerulonephritis and Schönlein- Henoch purpura].

We have recently examined polymorphisms of immunoglobuline heavy chain genes at S mu and S alpha 1 switch region loci by RFLP technique and described differences of genotype frequencies between healthy controls and patients with IgA-nephritis and Henoch-Schönlein-Purpura respectively. In the present study we further characterized the heavy chain constant region of IgG2 and IgG3 and, in addition, a hypervariable region (D 14 S 1) of unknown function localized downstream. In the present larger patient cohort we confirmed a higher frequency of S alpha 1 7.4 kb homozygotes in patients with IgA-nephritis (but not SHP), i.e. 62.0% vs 38.8% in controls, p less than 0.001. Compared to controls RFLP-frequencies of the constant region of IgG2 were also different in patients with IgA-nephritis, but not RFLP frequencies of D 14 S 1 or of the constant region of IgG3. Patients with IgA-nephritis homozygote for 7.4 kb in S alpha 1 had more adverse renal outcome and hypertension and more severe histological lesions (i.e. interstitial fibrosis, p less than 0.005).

Gene Frequency↗
PubMed1989

[Acquired cystic kidney disease and autosomal dominant polycystic kidney disease--precancerous condition?].

Acquired cystic kidney disease (ACKD) is a frequent complication of end-stage renal disease. In about 50% of patients on chronic haemodialysis treatment, secondary cysts are detected by sonography/computed tomography or at autopsy. ACKD is associated with an increased risk for the development of renal neoplasias. Renal adenomas are found in 8.8% of the cases, renal cell carcinomas are observed in 2.9% of the patients. The prevalence of renal cell carcinoma is 5-10 times greater in ACKD than in the general population. Therefore, ACKD should be considered as a precancerous condition carrying an increased risk for the development of renal cell carcinoma. Consequently patients with ACKD need careful and regular clinical observation and monitoring by ultrasound or computed tomography. An increased risk for the development of renal cell carcinoma has also been discussed in autosomal dominant polycystic kidney disease (ADPKD) based on anecdotal observations. A careful analysis of the literature as well as a retrospective examination of 86 necropsies (1951-1985) and 25 nephrectomy specimens with ADPKD revealed only one patient with renal cell carcinoma. With respect to the incidence of renal cell carcinoma and the frequency of ADPKD (1:1000) in the general population, the present data do not permit the conclusion that ADPKD represents a precancerous condition.

Genes, Dominant↗
PubMed1989

[Clinical pathology of the glomerulus--from phenomenon to entity. Focal sclerosis].

Three main types of global glomerular sclerosis (glomerular obsolescence) can be differentiated by light microscopy, immunohistochemistry and electron microscopy: the compressive type is characterized by an obliteration of the urinary space by type I collagen, the matrix type by a massive accumulation of mesangial matrix (sclerosis), and the insudative type is accompanied by marked subendothelial deposition of hyalin. Thus, different mechanisms may lead to glomerular obsolescence (scarring) even if mixed forms are frequently encountered. Segmental glomerular sclerosis represents a non-specific lesion observed in a variety of conditions. An increase in mesangial matrix and subendothelial deposition of hyalin material are the predominant histological features. The presence of segmental glomerular sclerosis, however, is of particular significance when occurring in the setting of an idiopathic nephrotic syndrome. The majority of patients (90%) are steroid-resistant and prone to develop renal failure. A rapidly progressive course is frequently observed when segmental lesions are superimposed to diffuse mesangial proliferation. The relationship between minimal change nephrotic syndrome and focal segmental glomerular sclerosis is still controversial. It is uncertain whether they represent two distinct, unrelated entities or whether they belong to the spectrum of a disease with focal segmental glomerular sclerosis being the more ominous end of the spectrum. The pathogenesis of segmental glomerulosclerosis is discussed.

Glomerulonephritis↗
PubMed1989

Detection and clinical implication of anti-neutrophil cytoplasm antibodies in Wegener's granulomatosis and rapidly progressive glomerulonephritis.

The specificity of anti-neutrophil cytoplasm antibodies (ACPA/ANCA) was investigated in patients suffering from Wegener's granulomatosis (WG), various forms of systemic diseases including vasculitides (non-WG), and different types of biopsy-proven glomerulonephritides. In particular, the diagnostic significance of ACPA/ANCA was assessed in patients affected by rapidly progressive glomerulonephritis with and without systemic manifestations. From 25 patients with active Wegener's granulomatosis 22 showed the classical diffuse finely granular cytoplasmic staining of neutrophils as did 4/31 patients with idiopathic rapidly progressive glomerulonephritis. One patient with biopsy confirmed Wegener's granulomatosis, six patients with microscopic polyarteritis and 3/31 patients with idiopathic rapidly progressive glomerulonephritis showed a focal cytoplasmic staining exhibiting a rosette-like pattern. One further patient with Wegener's granulomatosis displayed a prominent fluorescence of the outer nuclear membrane as well as a punctate-diffuse nuclear staining resembling that of granulocyte specific antibodies. Another patient with active Wegener's granulomatosis did not react in the ACPA/ANCA-test. These findings demonstrate different staining patterns of neutrophils which are related to different clinical entities within the spectrum of small vessel vasculitis. Moreover, they point out that different antigens are involved in the various types of vasculitis. In classical cases of Wegener's granulomatosis, but not in other forms of vasculitis, the titer of ACPA/ANCA showed a close relationship to the number of organs involved.

Adolescent↗
PubMed1988

The juxtaglomerular apparatus in Bartter's syndrome and related tubulopathies. An immunocytochemical and electron microscopic study.

A comparative immunocytochemical and electron microscopic study was performed on renal biopsies from two children with classical Bartter's syndrome (BS) and three children with a recently described variant, the so-called hyperprostaglandin E-syndrome (HES). Compared to age-matched controls, kidney specimens from patients with BS and HES disclosed a marked hypertrophy and hyperplasia of the juxtaglomerular apparatus (JGA). In addition, in HES focal tubular and interstitial calcifications accompanied by interstitial fibrosis and tubular atrophy were noted. On immunocytochemistry, chronic stimulation of the JGA in BS and HES was characterized by an increase in the number of renin-positive cells, particularly in the media of afferent arterioles, but also in efferent arterioles and in the glomerular stalk. The length of the renin-positive portion of the preglomerular arterioles was significantly increased when compared to controls (100 +/- 32 vs. 49 +/- 17 microns; p less than 0.001). In addition, the immunoreactivity of individual renin-positive cells was markedly enhanced. On electron microscopy, "hypertrophy" of the RER and of Golgi complexes with paracrystalline deposits in dilated RER cisterns and protogranules indicated an increased renin synthesis. Renin could be identified in mature secretory granules as well as protogranules by immune electron microscopy. Angiotensinogen was present in hypertrophied epithelial cells of Bowman's capsule. Converting-enzyme reactivity was observed in controls as well as in BS and HES in the brush border of the proximal tubule. In contrast to previous reports, Angiotensin II was completely negative in control as well as in diseased kidneys. We conclude from our results that both BS and HES are characterized by a marked activation of the JGA and severe stimulation of the renin-angiotensin system. Since activation of this system, however, leads--independently of the primary stimulus--to qualitatively very similar morphological reactions, these results do not implicate a common pathogenetic mechanism to both conditions.

Bartter Syndrome↗
PubMed1988

Identification of gastroenteropancreatic neuroendocrine cells in normal and neoplastic human tissue with antibodies against synaptophysin, chromogranin A, secretogranin I (chromogranin B), and secretogranin II.

Gastroenteropancreatic human neuroendocrine (NE) cells (normal and neoplastic) were investigated for the expression of the neuroendocrine-specific polypeptides synaptophysin, chromogranin A, secretogranin I (chromogranin B), and secretogranin II, using immunohistochemistry and immunoblotting. Monoclonal antibody against synaptophysin stained most, and possibly all, of the neuroendocrine cells in both normal and neoplastic tissue. Monoclonal antibody against chromogranin A also stained a high proportion of normal and neoplastic neuroendocrine cells. Immunostaining with polyclonal antisecretogranin I and antisecretogranin II antibodies was detectable in almost all of the normal and neoplastic tissue sections that were analyzed, and it was confined to a smaller population of neuroendocrine cells than that observed for synaptophysin and chromogranin A. Consistent with the immunohistochemical observations, immunoblotting revealed the presence of all four antigens in various tumors. The data show that synaptophysin and chromogranin A, for which monoclonal antibodies are commercially available, may be used as diagnostic markers for human gastroenteropancreatic tumors. Our results also suggest that the development of monoclonal antibodies against human secretogranins I and II will provide additional tools for a refined diagnosis of such tumors.

Antibodies, Neoplasm↗
PubMed1988

The spectrum of renal involvement in epidermolysis bullosa dystrophica hereditaria: report of two cases.

Epidermolysis bullosa dystrophica Hallopeau-Siemens (EBDH) is one of the most severe inherited epidermolyses, a group of mechanobullous dermatological disorders. We observed two patients presenting with a severely multilating type of EBDH who developed biopsy-proven renal disease, which substantially altered the evolution and pathogenesis of their disease. In a boy, chronic postinfectious glomerulonephritis developed, most probably due to recurring superinfections of bullous skin lesions. He also experienced acute oliguric renal failure due to severe diarrhea during exacerbation of EBDH. A female patient developed a nephrotic syndrome due to secondary amyloidosis. Hypoalbuminemia caused further fluid losses through bullous skin lesions, aggravating intravascular hypovolemia and leading to rapid renal failure secondary to bilateral renal vein thrombosis. The study shows that, although rare, renal complications may alter the natural course of EBDH.

Adolescent↗
PubMed1988

Renal disease and the development of hypertension in salt-sensitive Dahl rats.

To elucidate the role of the kidneys in the development of hypertension in Dahl salt-sensitive (S), as compared to resistant (R) rats of the JR strain, we analyzed functional and morphological changes before and after the administration of an 8% NaCl diet and the onset of hypertension. The diet was begun at six weeks of age and was continued until 12 weeks of age. At six weeks, blood pressure was not different between S and R rats. Hypertension occurred in S rats receiving the 8% NaCl diet at week 8, and in S rats receiving 0.9% NaCl at week 10. Albuminuria and proteinuria were found in S rats prior to the 8% NaCl diet and progressed regardless of diet. Electron microscopy of glomeruli revealed segmental loss of epithelial foot processes in S rats at six weeks prior to the 8% NaCl diet. Mesangial widening, arteriolar myo-intimal cell hyperplasia and interstitial fibrosis occurred in all S rats. Inulin and PAH clearances in S rats decreased with time, the changes being accelerated by the 8% NaCl diet. Micropuncture of S and R rats prior to the 8% NaCl diet revealed no glomerular hypertension in S rats. The number of glomeruli in S and R rats were not different. We conclude that prehypertensive S rats of the JR strain already have albuminuric glomerular disease not associated with reduced number of glomeruli or glomerular hypertension. The renal pathology is accelerated once hypertension develops. A lower NaCl intake delays, but does not prevent renal disease in S rats.

Albuminuria↗