In order to identify the relationship between eosinophil activation in
Henoch-Schonlein purpura (HSP) and IEA nephropathy, serum eosinophil
cationic protein (ECP) was analyzed in both conditions. The soluble in
terleukin-2 receptor (sIL-2R) was also analyzed, The levels of ECP wer
e significantly higher in HSP patients (mean 9.7 +/- 1.8 mu g/l) than
in a control group (mean 4.6 +/- 0.7 mu g/l). When the HSP patients we
re classified into two groups, one with normal urine and one with abno
rmal urine, the latter showed higher levels of ECP than the former. Le
vels of ECP were not significantly higher in IgA nephropathy patients
than in a control group. The sIL-2R levels were elevated in the serum
of HSP and IgA nephropathy patients compared with controls, In conclus
ion, eosinophil activation may be involved in the pathogenesis of HSP
but not in IgA nephropathy.