尋常性乾癬を合併したIgA腎症の1例

Abstract

A 55-year-old male patient presenting with psoriasis vulgaris and IgA nephropathy is reported. He was first noticed to have. proteinuria on an annual medical checkup at his company in 1979. Although proteinuria has been detected at every medical opportunity, he had never undergone closer evaluation. Scaly erythema on the right forehead had appeared since October 1984 and was diagnosed as psoriasis vulgaris by means of skin biopsy. In March 1985, he developed hypertension and was treated with antihyper- tensive drug by his family physician. Urinalysis showed proteinuria, hematuria and some hyaline casts. A 24-h urine collection contained 1.2g protein. Renal function test on admission was normal ; serum creatinine, 0.9mg/dl, creatinine clearance, 91ml/min. Immunoserological tests demonstrated that autoantibodies, serum complement titers and circulatory immune complexes (Clq binding assay) were all negative or within normal limits, except for the increase in serum IgA of 592mg/dl. The renal biopsy revealed diffuse mesangial proliferative glomerulonephritis. Immunofluorescence microscopy disclosed diffuse mesangial staining for IgA and C3. The diagnosis of IgA nephropathy was made. In spite of anti-platelet and anti-hypertensive therapy, his renal function gradually deteriorated over 8 years. Skin lesions still remain with remission and exacerbation. We discuss the relationship between IgA nephropathy and psoriasis vulgaris in this paper with reference to the literature.