Pattern of glomerular diseases in a tertiary center in Egypt: review of 10-year renal biopsy data

Abstract

Abstract Background and aims Glomerular diseases are a major cause of chronic kidney disease (CKD), accounting for approximately 20–25% of cases worldwide, particularly affecting younger populations. This study aimed to characterize the spectrum and distribution of glomerular diseases diagnosed at Ain Shams University Hospitals over a 10-year period (2009–2018). Method This retrospective observational study included all kidney biopsies processed at our institution between 2009 and 2018. Each specimen was examined using light microscopy, immunofluorescence, and, when indicated, electron microscopy. Diagnoses were classified into primary glomerular diseases (PGD), secondary glomerular diseases (SGD), and tubulointerstitial diseases (TID), according to standard histopathological criteria. Demographic, clinical, and laboratory data were analyzed alongside biopsy findings. Results A total of 999 renal biopsies were reviewed. Primary glomerular diseases (PGD) were identified in 453 patients (45.3%), secondary glomerular diseases (SGD) in 478 (47.8%), and tubulointerstitial diseases (TID) in 68 (6.8%). The cohort comprised 29.3% patients aged <18 years, 37.7% aged 18–40 years, and 33.0% aged >40 years. Among PGD, membranous nephropathy was the most frequent diagnosis, followed by immune complex–mediated membranoproliferative glomerulonephritis (MPGN), IgA nephropathy, minimal change disease, and primary focal segmental glomerulosclerosis (FSGS). Among SGD, lupus nephritis predominated, followed by secondary FSGS, post-infectious glomerulonephritis, diabetic nephropathy, and cryoglobulinemic GN. Within the TID group, chronic tubulointerstitial nephritis (TIN) was most common, followed by acute TIN and acute tubular necrosis. Age-stratified analysis showed that in patients <18 years, minimal change disease was the most frequent PGD, lupus nephritis was the leading SGD, and chronic TIN was the predominant TID. In patients aged 18–40 years, membranous nephropathy and lupus nephritis remained the most frequent PGD and SGD, respectively, while chronic TIN persisted as the most frequent TID. Among those aged >40 years, the same pattern was observed. Conclusion This large single-center study demonstrates a high burden of immune-mediated kidney diseases, with secondary glomerular diseases slightly exceeding primary forms. The predominance of lupus nephritis and membranous nephropathy reflects regional epidemiological patterns and underscores the importance of kidney biopsy in guiding diagnosis and management. Continuous surveillance through biopsy registries is essential to monitor evolving disease trends.