Epidemiological features of primary glomerular disease in Turkey: a multicenter study by the Turkish Society of Nephrology Glomerular Diseases Working Group

Abstract

Background The largest data on the epidemiology of primary glomerular diseases (PGDs) are obtained from the databases of countries or centers. Here, we present the extended results of the Primary Glomerular Diseases Study of the Turkish Society of Nephrology Glomerular Diseases (TSN-GOLD) Working Group. Methods Data of patients who underwent renal biopsy and received the diagnosis of PGD were recorded in the database prepared for the study. A total of 4399 patients from 47 centers were evaluated between May 2009 and May 2019. The data obtained at the time of kidney biopsy were analyzed. After the exclusion of patients without light microscopy and immunofluorescence microscopy findings, a total of 3875 patients were included in the study. Results The mean age was 41.5 ± 14.9 years. 1690 patients were female (43.6%) and 2185 (56.3%) were male. Nephrotic syndrome was the most common biopsy indication (51.7%). This was followed by asymptomatic urinary abnormalities (18.3%) and nephritic syndrome (17.8%). The most common PGD was IgA nephropathy (25.7%) followed by membranous nephropathy (25.6%) and focal segmental glomerulosclerosis (21.9%). The mean total number of glomeruli per biopsy was 17 ± 10. The mean baseline systolic blood pressure was 130 ± 20 mmHg and diastolic blood pressure was 81 ± 12 mmHg. The median proteinuria, serum creatinine, estimated GFR, and mean albumin values were 3300 (IQR: 1467–6307) mg/day, 1.0 (IQR: 0.7–1.6) mg/dL, 82.9 (IQR: 47.0–113.0) mL/min and 3.2 ± 0.9 g/dL, respectively. Conclusions The distribution of PGDs in Turkey has become similar to that in other European countries. IgA nephropathy diagnosed via renal biopsy has become more prevalent compared to membranous nephropathy.

Kidney biopsy-based epidemiologic analysis shows growing biopsy rate among the elderly

“…The results confirmed that glomerular diseases prevail over the other diagnoses similar to most of the registries 3 , 8 , 17 , 19 – 43 . Within glomerular diseases, IgA nephropathy was the most common entity, which correlates well with another Hungarian registry in a different region 44 , 45 and other registries in different countries 2 – 6 , 8 , 9 , 19 – 21 , 29 – 31 , 46 – 58 . Interestingly, there were some countries, mainly outside of Europe, where membranous nephropathy 22 , 23 , 26 , 38 , 59 , 60 or FSGS/MCD were the most frequently diagnosed 24 , 25 , 32 – 35 , 37 , 40 , 43 , 61 – 70 .…”

B Cells in Primary Membranous Nephropathy: Escape from Immune Tolerance and Implications for Patient Management

“…Membranous nephropathy (MN) is the most common cause of idiopathic nephrotic syndrome in adults [1]. Globally, the incidence rate of MN is up to 12 per million adults per year, although there is significant regional variation [1][2][3][4][5][6][7][8][9][10][11][12][13][14][15][16][17][18]. The incidence may be underestimated because only a small proportion of patients with MN progress to end-stage kidney disease (ESKD).…”

Clinical and pathologic features of primary membranous nephropathy in Turkey: a multicenter study by the Turkish Society of Nephrology Glomerular Diseases Working Group

“…Forty-seven nephrology units throughout Turkey have been providing data for the registry, including kidney-biopsy proven glomerular diseases. Previously, several studies have been conducted with the data obtained from this registry [ 8 , 10 , 11 ]. The total number of patients in the registry at the time of the evaluation was 4399.…”

“…The prevalence of MNP in Turkey was stated as 25.6% among 3875 primary glomerulonephritis patients by Turkmen et al. [ 8 ]. However, this study was an epidemiologic study and did not report clinical and pathologic features of MNP in detail.…”