ABSTRACT
We report a case of sporadic atypical hemolytic uremic syndrome (HUS) with a transient decrease in complement factor H. Referred for hemolysis and azotemia without diarrhea prodrome, this 31-month-old boy showed a decreased complement 3 (C3) and complement factor H (FH) level. However, the factor H gene (HF1) mutation was missing. After the hemolysis was controlled with plasma infusion, the C3 and FH levels recovered. The patient's renal function fully recovered and remained normal, and there was no recurrence of the HUS.
Subject(s)
Complement Factor H/analysis , Hemolytic-Uremic Syndrome/blood , Child, Preschool , Hemolytic-Uremic Syndrome/diagnosis , Humans , MaleABSTRACT
Glucocorticoids are widely prescribed for renal diseases. It is believed that glucocorticoids attenuate immune-mediated renal diseases by suppressing the cell-mediated immune system. However, there is evidence that glucocorticoids influence the expression of such growth factors as vascular endothelial growth factor (VEGF), transforming growth factor-beta1 (TGF-beta1), and connective tissue growth factor (CTGF), which are known to influence the development or progression of renal diseases. Therefore, we undertook this study to determine whether glucocorticoids regulate proteinuria or extracellular matrix (ECM) production by altering these growth factors. Mesangial proliferative glomerulonephritis was induced in rats by intravenous injection of monoclonal antibody (OX-7), and dexamethasone (20 mg/kg) was administered intraperitoneally from the third to seventh disease day. Glomerular expression of VEGF, TGF-beta1, and CTGF, the amount of urinary protein, and glomerular ECM were measured on the seventh disease day. The nephritic group showed proteinuria and greater VEGF, TGF-beta1, and ECM production. Dexamethasone aggravated proteinuria (protein, 0.4 +/- 0.1 mg/mg creatinine in the NC group, 6.3 +/- 2.0 mg/mg creatinine in the DC group, and 21.1 +/- 1.9 mg/mg creatinine in the D-Dex group; P < 0.05) and diminished VEGF release (22 +/- 3 pg/mg total protein in the NC group, 292 +/- 26 pg/mg total protein in the DC group, and 198 +/- 23 pg/mg total protein in the D-Dex group; P < 0.05). Expression of TGF-beta1, CTGF, and ECM was not altered significantly by dexamethasone treatment. We found that glucocorticoid diminishes VEGF release and at the same time exacerbates proteinuria in rats with this type of glomerulonephritis.