Mesangioproliferative glomerulonephritis with full-house pattern observed during treatment of immune thrombocytopenic purpura

Abstract

Abstract This study reports a rare case of mesangioproliferative glomerulonephritis with a full-house pattern in a 56-year-old Japanese man. Mesangioproliferative glomerulonephritis was observed during the treatment of immune thrombocytopenic purpura (ITP). After his diagnosis with ITP in 2012, abnormal urinary findings with renal dysfunction were observed in July 2018. His complement titers were low, and he was negative for antinuclear antibodies. A percutaneous renal biopsy was performed in January 2019. Light microscopy revealed mesangial cell proliferation and double basement membrane; immunofluorescence indicated a full-house pattern; and electron microscopy revealed electron-dense deposits in the mesangial and subendothelial regions. He was diagnosed with mesangioproliferative glomerulonephritis and non-lupus full-house nephropathy by renal biopsy. Because of coexisting hypocomplementemia and findings suggestive of membranoproliferative glomerulonephritis (MPGN) on renal biopsy, he was treated as MPGN clinically with prednisolone, and his urinary findings improved markedly. However, as the complement titers were still low, mycophenolate mofetil was also prescribed, which normalized complement levels. Production of anti-platelet antibodies is involved in the etiology of ITP. Although little is known about the mechanism by which ITP causes glomerulonephritis, including MPGN, glomerular deposition of circulating immune complexes synthesized by antiplatelet antibodies may be involved. This case shows full-house nephropathy, suggesting the involvement of immune complexes, which in turn, suggested an association between ITP and glomerulonephritis.