NEPHROTIC SYNDROME-ASSOCIATED WITH DIFFUSE MESANGIAL HYPERCELLULARITY- IS IT A HETEROGENEOUS DISEASE ENTITY

Diffuse mesangial hypercellularity (DMH) is a rare primary mesangial p roliferative glomerulonephritis associated with idiopathic nephrotic s yndrome (INS). We conducted this study on 15 patients, including 5 pat ients with repeated specimens, with a follow-up of 0.9-17.5 years and evaluated the clinical course and pathological findings. Seven patient s were male. Ten patients were under 14 years of age. All specimens ha d INS and were diagnosed morphologically with primary diffuse mesangia l proliferative glomerulonephritis at initial biopsy; 4 were diagnosed with focal segmental glomerulosclerosis (FSGS) within 3 years by the second biopsy. The remaining 11 patients included 8 initial responders and 3 initial nonresponders to 8 weeks' steroid therapy and had the h istologic variant of the minimal-change nephrotic syndrome (MCNS). Ten of the 11 patients had normal renal function during the investigation period. One patient with the MCNS variant who was refractory to stero id therapy developed end-stage renal disease (ESRD) within 6 years. Fo ur patient with the histologic variant of FSGS included 1 initial resp onder, 2 late responders, and 1 steroid-refractory case. One patient w ith the FSGS variant developed ESRD within 4 years. The follow-up biop sies documented that the severity of mesangial hypercellularity was as sociated with the severity of proteinuria or hematuria. We conclude th at DMH may be divided into heterogeneous disease entities, whereas mor phologic changes in initial biopsies were similar. Each variant as wel l as the degree of DMH should be recognized routinely by follow-up bio psy, because they are prognostic indicators.