Renal biopsy registry in Alexandria area

Abstract

Background There is a paucity of registries on diseases found on renal biopsies, especially in Egypt. Therefore, in this study, we have attempted to identify the pattern of renal pathology among renal biopsy (RB) specimens and to study the clinicopathological correlation of RB in the Alexandria area, which is considered the biggest second city in Egypt after Cairo, with around six million inhabitants, as a step toward generating a national RB registry. Methods We evaluated all the available adult native renal biopsies that were performed in the Alexandria area during the years 2012 and 2015 from the two main nephropathology centers. Clinical presentations were asymptomatic urinary abnormalities, nephrotic syndrome (NS), nephritic syndrome, and unexplained acute kidney injury. Renal diseases were divided into four major categories: (a) primary glomerulonephritides (GN); (b) secondary GN; (c) tubulointerstitial nephropathies (TIN); and (d) vascular nephropathies. The distinction between primary and secondary GN was not established by a single histological approach, but by association of the morphological findings and available clinical data. A RB forum was designed to collect the clinical and pathological data. Results 861 native renal biopsies were included; the most common age interval during which RB was performed was 20–30 years (32.6%); female gender (51%) was slightly more prevalent than male sex (49%). The renal specimen was inadequate in 14.1% of the cases. Of all biopsies, primary GN was the most frequent (64.3%), followed by secondary GN (27.8%), TIN (4.2%), and vascular nephropathies (1.2%), where end stage renal disease (ESRD) cases represented 2.4%. The most common clinical syndrome as an indication for RB was NS (57.8%), followed by acute kidney injury (21.6%), chronic kidney disease (CKD) (9.3%), asymptomatic urinary abnormalities (8.9%), nephritic syndrome (1.2%), and nephritic nephrotic syndrome (1.2%). At the time of the biopsy, 53.2% of the patients presented with elevated kidney functions. Mesangioproliferative GN was the most common primary GN (24.8%), followed by membranoproliferative GN (23.7%), focal and segmental glomerulosclerosis (21.4%), membranous nephropathy (10.3%), IgA nephropathy (8.8%), minimal change disease (5.7%), and crescentic GN (5.3%). Lupus nephritis was the most common cause of secondary GN (56.3%), followed by amyloidosis (14.6%), diabetic nephropathy (12.6%), nodular GN (6.8%), cast nephropathy (4.4%), cryoglobulinemia (2.9%), gouty nephropathy (1.9%), and lymphomatous infiltration (0.5%). Acute TIN represented 65.5% of the TIN cases and chronic TIN represented 35.5%. Thrombotic microangiopathy represented 66.6% of the vascular diseases and hypertension (HTN) nephrosclerosis represented 33.3%. Conclusion Our RB registry represents an important contribution toward understanding the epidemiology of renal diseases in Alexandria city. We are hoping that this registry will be the basis for developing a national registry. Establishment of a trusted national registry that will help in preventing and treating renal diseases requires good cooperation between nephrologists and pathologists, with collection of all clinical, serological, and pathological data.