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

BACKGROUND: We aimed to evaluate the features of primary membranous nephropathy (MNP) in Turkish people. METHODS: This is a retrospective analysis of patients with biopsy-proven primary MNP. We obtained the data collected between 2009 and 2019 in the primary glomerulonephritis registry of the Turkish Society of Nephrology Glomerular Diseases Study Group (TSN-GOLD). Patients with a secondary cause for MNP were excluded. Clinical, demographic, laboratory, and histopathological findings were analyzed. RESULTS: A total of 995 patients with primary MNP were included in the analyses. Males constituted the majority (58.8%). The mean age was 48.4 ± 13.9 years. The most common presentation was the presence of nephrotic syndrome (81.7%) and sub nephrotic proteinuria (10.3%). Microscopic hematuria was detected in one-third of patients. The median estimated glomerular filtration rate (eGFR) was 100.6 mL/min/1.73 m2 (IQR, 75.4-116.3), and median proteinuria was 6000 mg/d (IQR, 3656-9457). Serum C3 and C4 complement levels were decreased in 3.7 and 1.7% of patients, respectively. Twenty-four (2.4%) patients had glomerular crescents in their kidney biopsy samples. Basal membrane thickening was detected in 93.8% of cases under light microscopy. Mesangial proliferation and interstitial inflammation were evident in 32.8 and 55.9% of the patients, respectively. The most commonly detected depositions were IgG (93%), C3 complement (68.8%), and kappa and lambda immunoglobulin light chains (70%). Although renal functions were normal at presentation, vascular, interstitial, and glomerular findings were more prominent on biopsy in hypertensive patients. No significant effect of BMI on biopsy findings was observed. CONCLUSIONS: Despite some atypical findings, the main features of primary MNP in Turkey were similar to the published literature. This is the largest MNP study to date conducted in Turkish people.

Eggerthia catenaformis-related peritonitis in a patient with peritoneal dialysis.

Eggerthia catenaformis is a Gram-positive bacilli and an anaerobic and non-spore-forming bacterium, which rarely causes infections in humans. We present a case of peritonitis caused by E. catenaformis in a peritoneal dialysis patient. The isolate was identified as E. catenaformis with the MALDI-TOF MS method as in other cases in the literature. To the best of our knowledge, this is the first case of peritonitis caused by E. catenaformis in a human host.

Fabry Disease Prevalence in Renal Replacement Therapy in Turkey.

BACKGROUND: Fabry disease (FD) is an X-linked lysosomal storage disorder resulting from lack of alpha-galactosidase A (AGALA) activity in lysosomes. OBJECTIVE: In this multicenter study, we aimed to evaluate the prevalence of FD in renal transplant (Tx) recipients in Turkey. We also screened dialysis patients as a control group. METHODS: All Tx and dialysis patients were screened regardless of the presence of a primary disease. We measured the AGALA activity in all male patients as initial analysis. Mutation analysis was performed in male patients with decreased AGALA activity and in female patients as the initial diagnostic assay. RESULTS: We screened 5,657 patients. A total of 17 mutations were identified. No significant difference was observed between the groups regarding the prevalence of patients with mutation. We found FD even in patients with presumed primary kidney diseases. Seventy-one relatives were analyzed and mutation was detected in 43 of them. We detected a patient with a new, unknown mutation (p.Cys223) in the GLA gene. CONCLUSIONS: There are important implications of the screening. First, detection of the undiagnosed patients leads to starting appropriate therapies for these patients. Second, the transmission of the disease to future generations may be prevented by prenatal screening after appropriate genetic counseling. In conclusion, we suggest screening of kidney Tx candidates for FD, regardless of etiologies of chronic kidney disease.