Based on statistical analysis of data in 186 children, a formula was derived which allows accurate estimation of glomerular filtration rate (GFR) from plasma creatinine and body length (GFR (ml/min/1.73 sq m) = 0.55 length (cm)/Pcr (mg/dl). Its application to clearance data in a separate group of 223 children reveals excellent agreement with GFR estimated by the Ccr (r = .935) or Cin (r = .905). This formula should be useful for adjusting dosages of drugs excreted by the kidney and detecting significant changes in renal function.

Nephritis in Henoch-Schönlein purpura (HSP) is the primary cause of morbidity and mortality. Although many therapeutic regimens have been reported to be effective, no therapy has been shown in a controlled trial to be beneficial. Fifty-six patients with histopathologically severe HSP nephritis were randomized to receive supportive therapy with or without cyclophosphamide, 90 mg/m(2)/day for 42 days. Patients were classified according to status at final follow-up: Fully Recovered 48.2%, Persistent Abnormalities 39.3%, or ESRD/Death 12.5%. There were no differences in onset data or outcome between the two trial groups or in outcome between trial and 23 non-trial patients followed concurrently. Therefore, data from trial and non-trial patients were combined for further analysis. There was no correlation between outcome and age, blood pressure, serum total protein, or serum albumin. Although rates of proteinuria did not correlate with outcome, all those with progression to ESRD had nephrotic levels of proteinuria at onset. Only five of 28 patients with nephrotic levels of proteinuria and severe onset histopathology recovered fully. No patient with crescents in 50% or more of glomeruli went on to full recovery. Recurrence of non-renal symptoms did not correlate with outcome. Nephrotic syndrome, decreased GFR, and more severe histopathology at onset, as well as persistence of urinary abnormalities for several years, are ominous signs.

Summary. After acute administration of ammonium chloride, infants 1 to 16 months of age were similar to older children in their capacity to acidify their urine. The infants had a higher rate of excretion of titratable acid and a lower rate of excretion of ammonium but were similar in their rate of excretion of total hydrogen ion.Bicarbonate titrations performed in infants during the first year of life demonstrated a threshold ranging from 21.5 to 22.5 mmoles per L, maximal rate of reabsorption from 2.6 to 2.9 mmoles per 100 ml glomerular filtrate, and marked titration splay. A nephronic frequency distribution curve of the ratio of glomerular filtration rate to tubular reabsorptive capacity demonstrated both heterogeneity and skewing to the right, suggesting the presence of significant numbers of nephrons with low tubular transport capacity relative to filtration rate.

Sixty children, with biopsy diagnosed focal segmental glomerulosclerosis (FSGS) and with unremitting nephrotic syndrome despite intensive therapy with adrenocortical steroids, were randomly allocated into a clinical trial comparing prednisone, 40 mg/m2 on alternate days for a period of 12 months (control group), with the same prednisone regimen plus a 90-day course of daily cyclophosphamide, 2.5 mg/kg in a single morning dose (experimental group). One-quarter of the children in each group had complete resolution of proteinuria. The proportions of children with increased, unchanged, and decreased proteinuria by the end of the study were the same in the two groups. Treatment failure was defined as an increase in serum creatinine of 30% or more or greater than 0.4 mg/dl, or onset of renal failure. Treatment failure occurred in 36% of the control group and 57% of the experimental group (P> 0.1). Five patients died during the trial, 3 in the experimental group and 2 in the control group. A Kaplan-Meier survival analysis revealed no significant differences between the two groups. Cyclophosphamide therapy for children with steroid-resistant FSGS is not recommended.