Dušan Ferluga

Effect of intrauterine growth retardation on the clinical course and prognosis of IgA glomerulonephritis in children.

Intrauterine growth retardation (IUGR) resulting in a reduced number of nephrons is one of the nonimmune mechanisms that have been recently proposed as contributing to the progression of renal diseases. The purpose of our study was to determine whether IUGR has any effect on the clinical course and prognosis of IgA glomerulonephritis (IgA GN) in children. Fifty children with biopsy-proven IgA GN, who were followed for at least 3 years, were included. Six of the 50 children (12%) had signs of IUGR at birth, defined as birth weight below the 10th percentile for gestational age. There were no significant differences in initial clinical presentation between children with IUGR and those without IUGR. However, in kidney biopsy specimens, we found a significantly higher mean percentage of sclerotic glomeruli in children with IUGR than in those without IUGR (33 vs. 13%, p < 0.015). At the end of the follow-up period, we observed a significantly higher incidence of arterial hypertension in children with IUGR than in those without IUGR (50 vs. 11%, p < 0.05). Other differences between the two groups of children were not statistically significant. In conclusion, our study demonstrated an increased risk of the development of arterial hypertension and glomerulosclerosis in children with IgA GN who had suffered from IUGR with a birth weight below the 10th percentile for gestational age. IUGR may therefore help to identify early in the course of IgA GN those children who are at higher risk of an unfavorable course.

Is aristolochic acid a risk factor for Balkan endemic nephropathy-associated urothelial cancer?

Volker M. ARLT,* Dusan FERLUGA, Marie STIBOROVA, Annie PFOHL-LESZKOWICZ, Mato VUKELIC, Stjepan CEOVIC, Heinz H. SCHMEISER and Jean-Pierre COSYNS Section of Molecular Carcinogenesis, Institute of Cancer Research, Sutton, United Kingdom Institute of Pathology, University of Ljubljana, Ljubljana, Slovenia Department of Biochemistry, Charles University, Prague, The Czech Republic Ecole Nationale Superieure Agronomique de Toulouse, Laboratoire de Toxicologie et Securite Alimentaire, Auzeville Tolosane, France Department of Pathology, General Hospital, Slavonski Brod, Croatia Division of Molecular Toxicology, German Cancer Research Center, Heidelberg, Germany Department of Pathology, Universite Catholique de Louvain, Medical School, Brussels, Belgium

Scoring system for renal pathology in Fabry disease: report of the International Study Group of Fabry Nephropathy (ISGFN)

BACKGROUND In Fabry nephropathy, alpha-galactosidase deficiency leads to accumulation of glycosphingolipids in all kidney cell types, proteinuria and progressive loss of kidney function. METHODS An international working group of nephrologists from 11 Fabry centres identified adult Fabry patients, and pathologists scored histologic changes on renal biopsies. A standardized scoring system was developed with a modified Delphi technique assessing 59 Fabry nephropathy cases. Each case was scored independently of clinical information by at least three pathologists with an average final score reported. RESULTS We assessed 35 males (mean age 36.4 years) and 24 females (43.9 years) who mostly had clinically mild Fabry nephropathy. The average serum creatinine was 1.3 mg/dl (114.9 micromol/l); estimated glomerular filtration rate was 81.7 ml/min/1.73 m(2) and urine protein to creatinine ratio was 1.08 g/g (122.0 mg/mmol). Males had greater podocyte vacuolization on light microscopy (mean score) and glycosphingolipid inclusions on semi-thin sections than females. Males also had significantly more proximal tubule, peritubular capillary and vascular intimal inclusions. Arteriolar hyalinosis was similar, but females had significantly more arterial hyalinosis. Chronic kidney disease stage correlated with arterial and glomerular sclerosis scores. Significant changes, including segmental and global sclerosis, and interstitial fibrosis were seen even in patients with stage 1-2 chronic kidney disease with minimal proteinuria. CONCLUSIONS The development of a standardized scoring system of both disease-specific lesions, i.e. lipid deposition related, and general lesions of progression, i.e. fibrosis and sclerosis, showed a spectrum of histologic appearances even in early clinical stage of Fabry nephropathy. These findings support the role of kidney biopsy in the baseline evaluation of Fabry nephropathy, even with mild clinical disease. The scoring system will be useful for longitudinal assessment of prognosis and responses to therapy for Fabry nephropathy.

Pathology, Clinical Presentations, and Outcomes of C1q Nephropathy

C1q nephropathy is an uncommon glomerular disease with characteristic features on immunofluorescence microscopy. In this report, clinicopathologic correlations and outcomes are presented for 72 patients with C1q nephropathy. The study comprised 82 kidney biopsies from 28 children and 54 adults with male preponderance (68%). Immunofluorescence microscopy showed dominant or co-dominant staining for C1q in the mesangium and occasional glomerular capillary walls. Electron-dense deposits were observed in 48 of 53 cases. Light microscopy revealed no lesions (n = 27), focal segmental glomerulosclerosis (FSGS; n = 11), proliferative glomerulonephritis (n = 20), or various other lesions (n = 14). Clinical presentations in the patients who had no lesions histology were normal urine examination (7%), asymptomatic hematuria and/or proteinuria (22%), and nephrotic syndrome (minimal change-like lesion; 63%), which frequently relapsed. All patients with FSGS presented with nephrotic syndrome. Those with proliferative glomerulonephritis usually presented with chronic kidney disease (75%) or asymptomatic urine abnormalities (20%). Of the patients with sufficient follow-up data, complete remission of the nephrotic syndrome occurred in 77% of those with a minimal change-like lesion, progression to end-stage renal disease occurred in 33% of those with FSGS, and renal disease remained stable in 57% of those with proliferative glomerulonephritis. In conclusion, this study identified two predominant clinicopathologic subsets of C1q nephropathy: (1) Podocytopathy with a minimal change-like lesion or FSGS, which typically presents with nephrotic syndrome, and (2) a typical immune complex-mediated glomerular disease that varies from no glomerular lesions to diverse forms of glomerular proliferation, which typically presents as chronic kidney disease. Clinical presentation, histology, outcomes, and presumably pathogenesis of C1q nephropathy are heterogeneous.

Contribution to the pathogenesis of radiation-induced injury to large arteries

We report a case of a 35-year-old man who died of a brain infarct 20 months after radiotherapy for carcinoma of the tonsil with metastases to the cervical lymph nodes. Histology revealed mild atherosclerosis, necrotizing vasculitis, and occlusive thrombosis of the internal carotid artery. Significant changes were observed in the vasa vasorum: swelling and detachment of the endothelium, subendothelial oedema, hyaline change, fibrinoid necrosis of the vessel walls with mononuclear cellular infiltration, accompanied by focal haemorrhages and chronic inflammation in the periadventitial soft tissue. We believe that these changes of the vasa vasorum and necrotizing vasculitis are causally related and that vasculitis represents focal ischaemic necroses with inflammatory reaction. Our findings support the hypothesis, based on experimental studies, that injury to the vasa vasorum is an important mechanism in the development of radiation-induced vasculopathy of large arteries. They also suggest an evolution of the injury to the vasa vasorum and periadventitial tissue from the early lesions described in our patient, to late stages resulting in dense periadventitial fibrosis as reported previously. We suggest that injury to the vasa vasorum and the consequent ischaemic lesions of the arterial wall are morphological features distinguishing radiation-induced arterial injury from spontaneous atherosclerosis.

Laryngeal papillomatosis: molecular, histopathological, and clinical evaluation

Molecular, histopathological, and clinical studies were carried out on a series of 79 laryngeal papillomas (LP) from 36 patients in order to investigate the hypothesis that juvenile and adult LP may represent a biological entity causally related to Human papilloma virus (HPV) infection. Using in situ hybridization with biotin-labelled probes and polymerase chain reaction, we detected human papilloma virus (HPV) 6/11 in 28 of 29 juvenile LP, in 26 of 30 adult multiple, and in 17 of 20 adult solitary LP. None of LP was found to harbour HPV types 16, 18, 31, 33, and 51. There were no clear-cut histological differences between juvenile and adult LP, the presence of koilocytosis was equally observed in both, and there was no prevalent type of epithelial hyperplasia in either form, except that all three cases of atypical hyperplasias (precancerous lesions) were found among adult patients. During a 14 year follow-up, no carcinomatous transformation of LP was observed. All juvenile LP in our study had frequent recurrences of the disease, however, numerous surgical procedures were also required in 16 of 27 adult patients. Our study supports Lindebergs hypothesis of a similar pathogenesis for all forms of LP caused by the HPV types 6/11.

C1Q nephropathy in children

C1q nephropathy (C1qNP) is a peculiar form of glomerulonephritis characterized by mesangial immunoglobulin and complement deposits, predominantly C1q, with no evidence of systemic lupus erythematosus. We describe the incidence, manifestation, histopathologic findings, follow-up, treatment and outcome of C1qNP. Twelve C1qNP patients were identified among 131 children who had undergone renal biopsy, accounting for a 9.16% incidence of C1qNP. Light microscopy examination showed focal segmental glomerulosclerosis (FSGS) with or without diffuse mesangial proliferation (n=6), minimal change disease (MCD) (n=4) or focal glomerulonephritis (n=2). C1q deposits were found in all, while electron microscopy revealed visible deposits in nine cases. Eight children presented with nephrotic syndrome, while one had nephrotic proteinuria and renal insufficiency that progressed to end-stage renal failure. The remaining three patients presented with nonnephrotic proteinuria associated with microhematuria, hypertension or renal insufficiency. Only one nephrotic syndrome patient responded excellently to corticosteroids, while four became corticosteroid dependent, and three were corticosteroid resistant, showing a very poor response to other immunosuppressive therapy as well. Patients with non-nephrotic proteinuria demonstrated fixed laboratory findings. Most C1qNP patients had FSGS or MCD, the majority of them presenting with corticosteroid-dependent or corticosteroid-resistant nephrotic syndrome. The latter showed a very poor response to any immunosuppressive therapy and high risk for progressive renal insufficiency.

Consensus statement on screening, diagnosis, classification and treatment of endemic (Balkan) nephropathy

Currently used diagnostic criteria in different endemic (Balkan) nephropathy (EN) centers involve different combinations of parameters, various cut-off values and many of them are not in agreement with proposed international guidelines. Leaders of EN centers began to address these problems at scientific meetings, and this paper is the outgrowth of those discussions. The main aim is to provide recommendations for clinical work on current knowledge and expertise. This document is developed for use by general physicians, nephrologists, urologist, public health experts and epidemiologist, and it is hoped that it will be adopted by responsible institutions in countries harboring EN. National medical providers should cover costs of screening and diagnostic procedures and treatment of EN patients with or without upper urothelial cancers.

Microthrombotic/Microangiopathic Manifestations of the Antiphospholipid Syndrome

The paper presents an overview of clinical manifestations and histopathologic findings in different organs in microvascular thrombotic and microangiopathic antiphospholipid syndrome (MAPS). Subsets of antiphospholipid syndrome (APS) are presented and defined. Clinico-pathologic correlations seem insufficient so far, because of a lack of detailed systematic studies of the histopathology in different organs. Based on their own autopsy and biopsy studies, the authors propose a novel categorization of histopathologic lesions that occur in patients with classic and catastrophic APS. In addition to the already accepted category of a microvascular thrombotic type of lesions, microangiopathic lesions consistent with thrombotic microangiopathy are proposed to be included in new revised classification criteria for definite APS. Microvascular thrombotic and so far underestimated microangiopathic histopathologic lesions have been shown to appear in various combinations and of different ages in patients with both classic and catastrophic APS, which fits into the concept of MAPS. These preliminary findings of our studies are also in line with the most recent hypothesis of two main mechanisms in the pathogenesis of APS, emphasizing a key role of endothelial cell affection induced by aPL on the one hand and interference with coagulation cascade on the other side.

Laryngeal hyperplastic lesions, follow-up study and application of lectins and anticytokeratins for their evaluation.

A retrospective study of 878 biopsy specimens from 692 patients with laryngeal hyperplastic aberrations was performed according to the Kambic-Lenart classification. Special attention was focused on 88 patients with persistent or recurring disease. In these carcinoma developed in 17 (2.4%) patients, 12 (1.7%) of whom had had atypical hyperplasia. We therefore propose that the term precancerosis, which so definitely implies cancer, should be replaced with the expression risky epithelium where nothing is determined in advance, but a careful follow-up of the patients is imperative. In particular cases of laryngeal hyperplastic lesions, mainly in abnormal and in atypical hyperplasias when the tissue specimens are cut tangentially, the exact identification and position of individual epithelial cells is essential. In such cases histochemical and immunohistochemical methods yield more precise evaluation. Lectins and cytokeratins provide good markers of epithelial maturation. These results contribute to a more useful evaluation of laryngeal hyperplastic lesions, crucial for the choice of adequate therapy.