OBJECTIVETo study the clinical significance of serum levels of insulin-like growth factor 1 (IGF-1) and insulin-like growth factor binding protein 3 (IGFBP-3) in children with Henoch-Schonlein purpura (HSP) or Henoch-Schonlein purpura nephritis (HSPN).

METHODSThirty-one children with HSP were selected as the HSP group, and 28 children with HSPN were selected as the HSPN group. Another 31 healthy children were selected as the control group. ELISA was used to measure serum levels of IGF-1 and IGFBP-3 in each group. Measurement of 24-hour urinary protein excretion was performed using an automatic biochemical analyzer in the HSPN group. Serum immunoglobulin (Ig) levels, complement C3 level and complete blood counts in each group were determined, and urine analysis was also performed.

RESULTSSerum levels of IGF-1 and IGFBP-3 in the HSP group were significantly higher than in the control group (P<0.05), and serum levels of IGF-1 and IGFBP-3 in the HSPN group were significantly higher than in the HSP and control groups (P<0.05). Among 12 children who underwent renal puncture biopsy, patients with higher pathological grades had higher serum levels of IGF-1 and IGFBP-3. In children with HSPN, those with proteinuria had significantly higher serum levels of IGF-1 and IGFBP-3 than those without proteinuria (P<0.05). Levels of white cells, red cells, platelet count, complement C3, IgG, and IgA and IgA/C3 ratio were significantly higher in the HSP and HSPN groups than in the control group (P<0.05).

CONCLUSIONSIncreased serum levels of IGF-1 and IGFBP-3 are observed in the acute onset period of HSP, which may be related to the degree of proteinuria and renal damage. Serum levels of IGF-1 and IGFBP-3 may be indicators of renal involvement.