Membranous nephropathy associated with graft-versus-host disease in allogeneic bone marrow transplantation successfully treated with rituximab.

Introduction: The incidence of renal disease in patients who have received a hematopoietic stem cell transplant is relatively low. However, nephrotic syndrome occurs in some patients, and membranous nephropathy is the most common cause. Clinical case: A 58-year-old woman diagnosed with chronic myeloid leukemia was treated with nilotinib. She underwent an allogeneic bone marrow transplant with 100% HLA compatibility. Six months after the bone marrow transplant, she developed graft-versus-host disease affecting the mouth and salivary glands. She received tacrolimus at therapeutic doses. Without improvement, she developed nephrotic syndrome and anasarca. Diagnostic workshop: Serum creatinine 0.64 mg/dl, albumin 3.58 gr/dl, cholesterol 689 mg/dl, positive antinuclear antibodies. C3 and C4 were standard, ANCA C, P, and Anti DNA were negative, viral serologies for hepatitis B, C, and HIV were negative, 24-hour urine proteinuria was 4.9 g, urine sediment: eumorphic micro hematuria (20-30 red blood cells/field). Renal biopsy was conclusive of membranous glomerulopathy. PLA2R staining (phospholipase A2 receptor type M) was requested, which was positive. Evolution: The patient received oral prednisone at 1 mg/kg/day for two weeks without remission. Four doses of rituximab 375 mg/m2/week were added. The nephrotic syndrome gradually improved until it wholly resolved after treatment without any sign of relapse of chronic myeloid leukemia.