Membranoproliferative glomerulonephritis presenting as arthropathy and cardiac valvulopathy in hypocomplementemic urticarial vasculitis: a case report

INTRODUCTION Hypocomplementemic urticarial vasculitis syndrome is a rare disorder characterized by chronic urticarial vasculitis, arthralgia, arthritis, and hypocomplementemia. Previously, only six patients with concomitant hypocomplementemic urticarial vasculitis syndrome, Jaccoud's arthropathy, and valvular heart disease have been reported. CASE PRESENTATION A 30-year-old Korean man presented with hypocomplementemic urticarial vasculitis syndrome. In addition to urticarial cutaneous lesions, he experienced polyarthralgia and arthritis that resulted in progressive deformity of the joints of both hands, cardiac valvulopathy with mitral, tricuspid, and aortic regurgitation, and intermittent neck swelling with laryngeal edema. He also developed nephritis with azotemia. His renal biopsy results revealed membranoproliferative glomerulonephritis, type I. He showed a partial response to a combination therapy of steroid, cyclophosphamide, and mycophenolate mofetil. CONCLUSIONS We describe, to the best of our knowledge, the first case of glomerulonephritis presenting a arthropathy and cardiac valvulopathy in hypocomplementemic urticarial vasculitis syndrome. A combination of corticosteroids, cyclophosphamide, and mycophenolate mofetil appear to be a safe and effective treatment for nephropathy, however are less effective for cutaneous vasculitis, cardiac valvulopathy, and arthropathy.