title: Anti-hLAMP2-antibodies and dual positivity for anti-GBM and MPO-ANCA in a patient with relapsing pulmonary-renal syndrome.
abstract: BACKGROUND
  Pulmonary-renal syndrome associated with anti-glomerular basement membrane (GBM) antibodies, also known as Goodpasture's syndrome, is a rare but acute and life-threatening condition. One third of patients presenting as anti-GBM antibody positive pulmonary-renal syndrome or rapidly progressive glomerulonephritis are also tested positive for anti-neutrophil cytoplasmic antibodies (ANCA). Whilst anti-GBM disease is considered a non-relapsing condition, the long-term course of double-positive patients is less predictable.
  
  
  METHODS
  We report a patient with such dual positivity, who presented with pulmonary hemorrhage, crescentic glomerulonephritis and membranous nephropathy. Plasmapheresis in combination with immunosuppressive therapy led to a rapid remission but the disease relapsed after two years. The serum of the patient was tested positive for antibodies to human lysosomal membrane protein 2 (hLAMP2), a novel autoantigen in patients with active small-vessel vasculitis (SVV). The anti-hLAMP2 antibody levels correlated positively with clinical disease activity in this patient.
  
  
  CONCLUSIONS
  We hypothesize that this antibody may indicate a clinical course similar to ANCA-associated vasculitis in double-positive patients. However, this needs to be confirmed on comprehensive patient cohorts.
authors.affiliation: Division of Nephrology, University Hospital Zurich, Zurich, Switzerland.
authors.forename: Christoph
authors.initials: C
authors.lastname: Etter
authors.forename: Ariana
authors.initials: A
authors.lastname: Gaspert
authors.forename: Stephan
authors.initials: S
authors.lastname: Regenass
authors.forename: Rudolf P
authors.initials: RP
authors.lastname: Wüthrich
authors.forename: Thomas
authors.initials: T
authors.lastname: Kistler
authors.forename: Renate
authors.initials: R
authors.lastname: Kain
authors.forename: Clemens D
authors.initials: CD
authors.lastname: Cohen
mesh_terms: D056648:Anti-Neutrophil Cytoplasmic Antibody-Associated Vasculitis / Q000276:immunology; D000888:Antibodies, Anti-Idiotypic / Q000097:blood*; D019268:Antibodies, Antineutrophil Cytoplasmic / Q000097:blood*; D001323:Autoantibodies / Q000097:blood*; D005260:Female; D005921:Glomerulonephritis / Q000097:blood / Q000276:immunology* / Q000628:therapy; D006470:Hemorrhage / Q000097:blood / Q000276:immunology* / Q000628:therapy; D006801:Humans; D007166:Immunosuppressive Agents / Q000627:therapeutic use; D008171:Lung Diseases / Q000097:blood / Q000276:immunology* / Q000628:therapy; D052119:Lysosomal-Associated Membrane Protein 2; D051907:Lysosomal Membrane Proteins / Q000276:immunology*; D008875:Middle Aged; D010956:Plasmapheresis; D012008:Recurrence; D016896:Treatment Outcome
chemical_list: D000888:Antibodies, Anti-Idiotypic; D019268:Antibodies, Antineutrophil Cytoplasmic; D001323:Autoantibodies; D007166:Immunosuppressive Agents; C497811:LAMP2 protein, human; D052119:Lysosomal-Associated Membrane Protein 2; D051907:Lysosomal Membrane Proteins; C051951:antiglomerular basement membrane antibody