A MCKAY1, N GRAF1,2, P KIRWAN3, D HAHN1, A DURKAN1,2
1The Children’s Hospital at Westmead, Sydney, NSW; 2 University of Sydney, NSW; 3Concord Repatriation General Hospital, Sydney, NSW,
Background: Henoch Schönlein nephritis affects 20-54% of children presenting with Henoch Schönlein Purpura (HSP). Histopathologic findings of HSP nephritis are varied however typically include mesangial glomerulonephritis with dominant or co-dominant IgA deposition. IgG, IgM, fibrinogen and C3 deposition may also occur. C1q deposition however is rare and raises the suspicion of lupus nephritis. We describe the clinical course and pathological findings in 3 children with HSP nephritis, positive streptococcal serology and the rare finding of positive C1q staining.
Case Report: Three male children presented with clinical features of HSP and renal involvement (nephrotic range proteinuria +/- renal impairment) within a 2 month period. In all three cases the ASOT and DNAseB were elevated. In two, the serum C3 and C4 were reduced and in the other case there was isolated C4 reduction. Histopathology demonstrated mesangial proliferation with IgA deposits, C1q deposition and subepithelial electron dense deposits. The children were treated with steroids, mycophenolate and lisinopril. Two of the three cases responded well with resolution of proteinuria at 3 months and one case has ongoing proteinuria.
Conclusions: C1q deposition has previously been considered a rare finding in HSP nephritis. However, in our case series we demonstrate C1q staining in three patients presenting within a short time frame to our tertiary children’s hospital. Further investigation is required to investigate if C1q deposition is a feature of more severe HSP nephritis associated with streptococcal infection.