A two-year-old boy with nephrotic syndrome took the fatal clinical course due to the wide spread cerebral thrombosis, associted with the hypercoagulopathy. The thrombosis in nephrotic syndrome have been sometimes noted in the patients with hypoalubminemia, hypercholesterolemia, and massive proteinuria. However, few cases with cerebral thrombosis has been reported. In our patient, the hypercoagulopathy was exacervated by the steroid therapy and by suffering from the infections of mumps and varicella. The immunoelectrophoretic study of the scrum protein in the patient revealed the transient in-crement of the monoclonal IgM (k type) twice after these viral infection. The appearance of the monoclonal protein in serum suggested that the cellular immunity was deficient in the patient. It was identified by the clinical immunological examinations such as negative delayed hypersentivity, reduced PHA responce, and decreased MIF. At autopsy, the thymus was grossly hypoplastic, which revealed that Hassall's corpuscles were rudimental, and numbers of lymphocytes were decreased. The brain showed the multiple thrombosis with subarachnoidal hemorrhage. But no thrombosis was found in other organs. Histological exami-nation in the kidney showed membranoproliferative and lobular glomerulonephritis. There was evidence of Rio and fibrinogen deposition within the glomeruli by immunofluorescent microscopy. On electron microscopy, there was subendothelial deposit in the glomeruli. Based upon the findings in the present case, we propose that some case of nephrotic syndrome might be associated with the cellular immunodeficiency.
