Background: There is currently little information in literature about the pattern of glomerulonephritides (GN) in adults with nephrotic syndrome in this part of the world, particularly that involving the use of immunofluorescence (IMF) and electron microscopy (EM). A few studies reported are based on light microscopic study alone and hence do not reflect the true pattern of GN underlying nephrotic syndrome. We carried out this study in the Department of Histopathology, Sindh Institute of Urology and Transplantation (SIUT), Karachi, Pakistan to determine, for the first time, the true pattern of GN in adult nephrotic patients from Pakistan. SIUT is a tertiary care center for renal and urologic disease in Pakistan. The Histopathology Laboratory of SIUT is equipped with all the modalities, including EM, required for precise diagnosis of glomerular disease.
Methods: This is a retrospective clinicopathologic study involving retrieval of clinical and pathological data from a review of original renal biopsy reports of adult patients with nephrotic syndrome who presented at the adult nephrology clinic of SIUT from July 1996 till July 2006. Two cores of renal tissue were routinely obtained. One core was fixed in 10% buffered formalin and processed for light microscopy; the other core was divided into two halves, for EM and the IMF study.
Results: A total of 316 adult patients were included. Of these, 201 (63.6%) were male and 115 (36.4%) were female. Mean age was 28.4 +/- 10.51 years with a range of 16-78 years. The spectrum of pathological lesions in the adult nephrotic population was wide and comprised focal segmental glomerulosclerosis (FSGS) (39.87%), followed by membranous GN (MGN) (26.58%), minimal change disease (MCD) (14.82%), mesangiocapillary GN (4.3%), mesangioproliferative GN (4.11%), post-infectious GN (2.84%), IgA nephropathy (2.53%), and other rare lesions.
Conclusions: Results from this study indicate that FSGS is the single most common cause of nephrotic syndrome in adult nephrotic patients, followed by MGN, and MCD. Our data are similar to those reported in recent series from the US. The study defines the pattern of glomerular disease in adult nephrotic patients for the first time in this region, because it is based on light microscopy, serology, IMF, and EM findings.