Miroslav Tišljar

Non-diabetic renal disease in Croatian patients with type 2 diabetes mellitus

AIM Our study aimed to examine the prevalence of non-diabetic renal disease in selected patients with type 2 diabetes mellitus and to determine important risk factors for non-diabetic renal disease. METHODS We conducted retrospective analysis of clinical, laboratory and pathohistological data of type 2 diabetes mellitus patients in whom renal biopsies were performed from January 2004 to February 2013 at Dubrava University Hospital Zagreb Croatia (n=80). RESULTS According to renal biopsy findings, isolated diabetic nephropathy was found in 46.25%, non-diabetic renal disease superimposed on diabetic nephropathy in 17.5% and isolated non-diabetic renal disease in 36.25% of the patients. The most common non-diabetic renal diseases found were: membranous nephropathy, followed by IgA nephropathy and focal segmental glomerulosclerosis. In univariate analysis shorter duration of diabetes, independence of insulin therapy, lower levels of HbA1c and absence of diabetic retinopathy were found to be significant clinical predictors of non-diabetic renal disease. In multivariate analysis only independence of insulin therapy (OR 4.418, 95%CI=1.477-13.216) and absence of diabetic retinopathy (OR 5.579, 95%CI=1.788-17.404) were independent predictors of non-diabetic renal disease. CONCLUSIONS This study confirmed usefulness of renal biopsy in patients with type 2 diabetes mellitus, due to the high prevalence of non-diabetic renal disease found. Since non-diabetic renal disease are potentially curable, we should consider renal biopsy in selected type 2 diabetes mellitus patients with renal involvement, especially in those with absence of diabetic retinopathy and independence of insulin therapy.

Prognostic significance of glomerular and tubulointerstitial morphometry in idiopathic membranous nephropathy

The purpose of our study was to investigate the prognostic value of clinical and pathological, in particular glomerular and tubulointerstitial morphometric variables in idiopathic membranous nephropathy (IMN). We prospectively followed 60 Caucasian patients diagnosed with idiopathic membranous nephropathy for at least 2 years or until primary outcome (≥50% permanent decrease in estimated glomerular filtration rate or death). Glomerular and tubulointerstitial morphometric variables at the time of renal biopsy were analyzed with respect to this outcome. Univariate analysis revealed that significant negative prognostic factors for this outcome were higher cholesterol and smaller albumin concentrations, higher creatinine and maximal 24-h proteinuria, higher grade of nephroangiosclerosis, higher glomerular basement membrane thickness and glomerulopathy index, higher interstitial fibrosis and tubular atrophy percentage and higher injury score. In multivariate analysis, only the maximal 24-h proteinuria and interstitial fibrosis and tubular atrophy percentage were independent predictors of this outcome. The results suggest that morphometric analysis, mainly quantitative measurement of interstitial fibrosis and tubular atrophy percentage, injury score, glomerular basement membrane thickness and glomerulopathy index could be used as an additional method for risk stratification of patients with idiopathic membranous nephropathy.

IgM as a novel predictor of disease progression in secondary focal segmental glomerulosclerosis.

Aim To determine the role of immunoglobulin M (IgM) deposits in clinical manifestations, disease outcome, and treatment response of idiopathic and secondary focal segmental glomerulosclerosis (FSGS). Methods Kidney biopsy specimens of 171 patients diagnosed with FSGS (primary and secondary) and 50 control patients were retrospectively included in the study. For each patient, clinical and outcome data were obtained and compared to morphological parameters, including immunofluorescence analysis of mesangial IgM and complement 3 (C3) deposits analyzed on kidney biopsy samples. Results There were significant positive correlations between IgM and C3 deposition in secondary FSGS (P < 0.001) and between IgM and mesangial deposits detected by electron microscopy in secondary FSGS (P = 0.015), which indicated that higher IgM deposition correlated with higher C3 deposition and mesangial deposits only in secondary FSGS. Patients with secondary FSGS and the deposition of IgM showed inferior renal outcomes at earlier time points in comparison with patients with negative IgM expression (P = 0.022). Conclusions We detected a positive correlation between IgM and C3 in secondary FSGS. The association between IgM deposition and worse renal outcome in secondary FSGS indicates that IgM may play a role in the progression of this disease.