title: Pregnancy in a Patient With Primary Membranous Nephropathy and Circulating Anti-PLA2R Antibodies: A Case Report.
abstract: There is little information about pregnancy outcomes in patients with active membranous nephropathy (MN), especially those with circulating autoantibodies to M-type phospholipase A₂receptor (PLA₂R), the major autoantigen in primary MN. We present what we believe to be the first known case of successful pregnancy in a 39-year-old woman with PLA₂R-associated MN. In the year prior to pregnancy, the patient developed anasarca, hypoalbuminemia (albumin, 1.3-2.2g/dL), and proteinuria (protein excretion, 29.2 g/d). Kidney biopsy revealed MN with staining for PLA₂R, and the patient was seropositive for anti-PLA₂R autoantibodies. She did not respond to conservative therapy and was treated with intravenous rituximab (2 doses of 1 g each). Several weeks after presentation, she was found to be 6 weeks pregnant and was closely followed up without further immunosuppressive treatment. Proteinuria remained with protein excretion in the 8- to 12-g/d range. Circulating anti-PLA₂R levels declined but were still detectable. At 38 weeks, a healthy baby girl was born, without proteinuria at birth or at her subsequent 6-month postnatal visit. At the time of delivery, the mother still had detectable circulating anti-PLA₂R of immunoglobulin G1 (IgG1), IgG3, and IgG4 subclasses, although at low titers. Only trace amounts of IgG4 anti-PLA₂R were found in cord blood. Potential reasons for the discrepancy between anti-PLA₂R levels in the maternal and fetal circulation are discussed.
authors.affiliation: Department of Medicine, Renal Section, Boston University Medical Center, Boston, MA.
authors.forename: Laith
authors.initials: L
authors.lastname: Al-Rabadi
authors.affiliation: Department of Medicine, Renal Section, Boston University Medical Center, Boston, MA.
authors.forename: Rivka
authors.initials: R
authors.lastname: Ayalon
authors.affiliation: Department of Medicine, Renal Section, Boston University Medical Center, Boston, MA.
authors.forename: Ramon G
authors.initials: RG
authors.lastname: Bonegio
authors.affiliation: Department of Obstetrics and Gynecology, Boston University Medical Center, Boston, MA.
authors.forename: Jennifer E
authors.initials: JE
authors.lastname: Ballard
authors.affiliation: Department of Pediatrics, Boston University Medical Center, Boston, MA.
authors.forename: Alan M
authors.initials: AM
authors.lastname: Fujii
authors.affiliation: Department of Pathology and Laboratory Medicine, Boston University Medical Center, Boston, MA.
authors.forename: Joel M
authors.initials: JM
authors.lastname: Henderson
authors.affiliation: Department of Medicine, Renal Section, Boston University Medical Center, Boston, MA.
authors.forename: David J
authors.initials: DJ
authors.lastname: Salant
authors.affiliation: Department of Medicine, Renal Section, Boston University Medical Center, Boston, MA. Electronic address: lhbeckjr@bu.edu.
authors.forename: Laurence H
authors.initials: LH
authors.lastname: Beck
mesh_terms: D000328:Adult; D001323:Autoantibodies / Q000276:immunology*; D005260:Female; D015433:Glomerulonephritis, Membranous / Q000188:drug therapy / Q000276:immunology*; D006801:Humans; D007166:Immunosuppressive Agents / Q000627:therapeutic use; D011247:Pregnancy; D011248:Pregnancy Complications / Q000276:immunology*; D054507:Receptors, Phospholipase A2 / Q000276:immunology*; D000069283:Rituximab / Q000627:therapeutic use
chemical_list: D001323:Autoantibodies; D007166:Immunosuppressive Agents; D054507:Receptors, Phospholipase A2; D000069283:Rituximab
keywords: M-type phospholipase A(2) receptor (PLA(2)R); Membranous nephropathy (MN); autoantibody; immunoglobulin G (Ig G) subclass; nephrotic syndrome; placenta; pregnancy; rituximab