Table 1.

Definitions on the basis of references (9,10,64) and on the authors’ clinical experience

Nephrotic Syndrome

Edema

Massive proteinuria (>40 mg/m2 per h in children, >3.5 g/d in adults)

Hypoalbuminemia (<2.5 g/dl)

Remission

Resolution of edema

Normalization of serum albumin (≥3.5 g/dl)

Marked reduction in proteinuria

Complete remission (<4 mg/m2 per h or negative dipstick in children, <0.3 g/d in adults)

Partial remission (<2 g/1.73 m2 per d, decreased by 50% and serum albumin ≥2.5 g/dl in children, <3.5 g/d and decreased by 50% in adults)

Relapse

Recurrence of massive proteinuria (>40 mg/m2 per h in children, >3.5 g/d in adults)

Positive urine dipstick (≥3+ for 3 d or positive for 7 d, usually applicable to children)

±Edema

Steroid-Sensitive Nephrotic Syndrome

Response to PDN 60 mg/m2 per d within 4–6 wk ±MPD boluses in children

Response to PDN 1 mg/kg per d or 2 mg/kg every other d, within 16 wk in adults

Nonrelapsing Nephrotic Syndrome

No relapses for >2 yr after the end of therapy for the first episode of nephrotic syndrome (applicable to children, not yet defined in adults)

Infrequently Relapsing Nephrotic Syndrome

<2 relapses per 6 mo (or <4 relapses per 12 mo)

Frequently Relapsing Nephrotic Syndrome

≥2 relapses per 6 mo (or ≥4 relapses per 12 mo)

Steroid-Dependent Nephrotic Syndrome

Relapse during steroid therapy or within 15 d of discontinuation

Steroid-Resistant Nephrotic Syndrome

No response to PDN 60 mg/m2 per d within 4 wk ±MPD boluses in children

No response to PDN 1 mg/kg per d or 2 mg/kg every other d, within 16 wk in adults

Multidrug-Resistant Nephrotic Syndrome

Poorly defined as absence of partial remission after 6 mo OR absence of complete remission after 2 yr

Treatment often consists of MPD boluses + oral prednisone for 6 mo + CsA and, in some cases, rituximab. Other protocols are also used

PDN, prednisone; MPD, methylprednisolone; CsA, cyclosporine A.