Objective: Scabies-associated glomerulonephritis (SGN) is often seen in certain populations, but little is known about its incidence, clinical characteristics, prognosis and pathogenesis.
Methodology: 376 patients with scabies were enrolled and divided into scabies-alone group (group A) and SGN group (group B) based on the presence or absence of glomerulonephritis. Clinical indicators and various biomarkers, including serum C-reactive protein, complement components C3 and C4, immunoglobulin, TNF-α, IL-6, IL-1β, and IL-18 in the early stage of the disease, were determined before and after treatment. All patients were follow-up in the clinic.
Results: 16 scabies patients developed SGN in this study. The clinical manifestations included glomerular hematuria and/or mild-moderate proteinuria. The manifestations associated with kidney injury in most of these patients completely resolved 2-6 months after scabies was cured. Compared to the patients in group A, the levels of serum CRP, IgG, TNF-α, IL-6, and IL-18 increased significantly and the serum C3 level decreased significantly in the patients in group B. Twelve patients with SGN achieved a clinical cure. Compared to the early stage of the disease, the levels of serum IgG, hs-CRP, TNF-α, IL-6, and IL-18 in these patients decreased significantly after being cured, and the serum C3 level increased significantly.
Conclusions : SGN is generally mild and has a good prognosis. The mechanisms may involve the generation of specific antibodies stimulated by itch mites, triggering of excessive immune and inflammatory responses.