ABSTRACT: BACKGROUND:Visceral disseminated varicella zoster virus (VDVZV) infection is a rare disease with a high mortality rate (55%) in immunocompromised patients, but it is not yet widely recognized in the field of nephrology. We report a case of VDVZV contracted during immunosuppressive therapy for membranous nephropathy. CASE PRESENTATION:A 36-year-old woman was diagnosed with membranous nephropathy and was being treated with immunosuppressive therapy consisting of 60?mg/day prednisolone, 150?mg/day mizoribine, and 150?mg/day cyclosporine. Nephrosis eased; therefore, the prednisolone dosage was reduced. However, 50?days after starting immunosuppressive therapy, the patient suddenly developed strong and spontaneous abdominal pain, predominantly in the epigastric area, without muscular guarding or rebound tenderness. Blood data indicated neutrophil-dominant elevated white blood cell count, reduced platelet count, elevated transaminase and lactate dehydrogenase, slightly increased C-reactive protein, and enhanced coagulability. Abdominal computed tomography revealed a mildly increased enhancement around the root of the superior mesenteric artery with no perforation, intestinal obstruction, or thrombosis. The cause of the abdominal pain was unknown, so the patient was carefully monitored and antibiotic agents and opioid analgesics administered. The following day, blisters appeared on the patient's skin, which were diagnosed as varicella. There was a marked increase in the blood concentration of VZV-DNA; therefore, the cause of the abdominal pain was diagnosed as VDVZV. Treatment with acyclovir and immunoglobulin was immediately started, and the immunosuppressive therapy dose reduced. The abdominal pain resolved rapidly, and the patient was discharged 1?week after symptom onset. DISCUSSIONS AND CONCLUSIONS:This patient was VZV-IgG positive, but developed VDVZV due to reinfection. Abdominal pain due to VDVZV precedes the skin rash, which makes it difficult to diagnose before the appearance of the rash, but measuring the VZV-DNA concentration in the blood may be effective. Saving the patient's life requires urgent administration of sufficient doses of acyclovir and reduced immunosuppressive therapy.