Schistosoma japonicum infection associated with membranous nephropathy: a case report

BACKGROUND: Schistosomiasis is one of the most contagious parasitic diseases affecting humans; however, glomerular injury is a rare complication mainly described with Schistosoma mansoni infection. We report a case of membranous nephropathy associated with Schistosoma japonicum infection in a Chinese man. CASE PRESENTATION: A 51-year-old Chinese male with a long history of S. japonicum infection presented to the hospital with a slowly progressing severe lower limb edema and foaming urine for over 5 months. Serum S. japonicumantigen test was positive and immunohistochemistry showed that the glomeruli were positive for the antigens. The renal pathologic diagnosis was stage III membranous nephropathy. The patient was treated with glucocorticoid, praziquantel, and an angiotensin-converting enzyme inhibitor. The edema in both lower limbs disappeared within 2 weeks, but his renal function declined progressively and proteinuria persisted after 5 months of therapy. CONCLUSIONS: Different classes of schistosomal glomerulopathy have completely different clinical manifestation and prognosis. Therefore, efforts should focus on alleviating symptoms, prevention, and early detection. S. japonicumassociated with membranous nephropathy may show a good curative effect and prognosis. However, it is necessary to monitor the renal function in such patients.