title: Myeloperoxidase-antineutrophil cytoplasmic antibody-negative microscopic polyangiitis with pulmonary haemorrhage and IgA nephropathy.
abstract: OBJECTIVE
  To report a case of a patient with myeloperoxidase-antineutrophil cytoplasmic antibody (ANCA)-negative microscopic polyangiitis (MPA) and IgA nephropathy associated with severe pulmonary haemorrhage.
  
  
  METHODS
  A 59-year-old man presented with ANCA-negative systemic vasculitis accompanied by purpura, nephritis and pulmonary haemorrhage. A skin biopsy specimen revealed pandermal leucocytoclastic vasculitis without IgA deposition and a kidney biopsy showed mesangial nephritis with IgA deposition. Considering these findings, the patient was diagnosed as having MPA with IgA nephropathy.
  
  
  CONCLUSIONS
  In most cases, MPA presents with rapidly progressive necrotizing glomerulonephritis and sometimes lung haemorrhage, while IgA nephropathy is less common among MPA cases. As recent research suggested that in MPA immunoglobulin deposition in the kidney may be an exacerbating factor for renal dysfunction and poor prognosis, close observation is required in these cases.
authors.affiliation: Department of Dermatology, Graduate School of Medicine, Kyoto University, Kyoto, Japan.
authors.forename: Yuichiro
authors.initials: Y
authors.lastname: Endo
authors.forename: Haruka
authors.initials: H
authors.lastname: Minato
authors.forename: Reiko
authors.initials: R
authors.lastname: Taki
authors.forename: Mayumi
authors.initials: M
authors.lastname: Kato
authors.forename: Satoshi
authors.initials: S
authors.lastname: Kore-Eda
authors.forename: Yoshiki
authors.initials: Y
authors.lastname: Miyachi
authors.forename: Miki
authors.initials: M
authors.lastname: Tanioka