Presenting features and short-term outcome according to pathologic variant in childhood primary focal segmental glomerulosclerosis.

BACKGROUND This was a retrospective analysis of children in one center who had primary (idiopathic) FSGS. DESIGN, SETTING, PARTICIPANTS, AND MEASUREMENTS There were 41 patients: 34.1% female, 65.9% male, 80.5% black, and 19.5% white. At presentation, the mean age was 10.9 +/- 0.9 yr. The mean time of follow-up was 3.9 +/- 0.5 yr. RESULTS During the observation period, the systolic BP (SBP) and diastolic BP (DBP) remained stable, serum albumin rose slightly, and the GFR was stable. Among those who received corticosteroids at presentation, 21.2% were steroid sensitive. At last follow-up among all patients, 71% were in remission, 78% had stage 1 or 2 chronic kidney disease, and 4.9% had reached ESRD. At last follow-up, the GFR was significantly higher (P = 0.01) in patients who were initially steroid sensitive. Ethnicity had no effect on clinical data or response to therapy. The pathologic variants were as follows: Cellular, 32%; collapsing, 24%; and not otherwise specified (NOS), 44%. The chronicity scores were as follows: Cellular, 4.3; collapsing 6.4; and NOS, 4.0 (significantly higher, P = 0.02, in collapsing versus NOS). At presentation, SBP (P = 0.03) and DBP (P = 0.03) were significantly higher and GFR was lower (P = 0.03) in patients with the collapsing compared with NOS variant. Remission after the initial course of corticosteroids was less common with the collapsing variant. At last follow-up, SBP (P = 0.02) and DBP (P = 0.04) were significantly higher in patients with the collapsing versus NOS variant. CONCLUSIONS The short-term outcome in pediatric primary FSGS is generally favorable, but a more guarded prognosis exists for patients with collapsing FSGS.