title: ANCA associated glomerulonephritis in a patient with mixed connective tissue disease.
abstract: OBJECTIVE
  To investigate the diagnosis and treatment of mixed connective tissue disease (MCTD) and myeloperoxidase-antineutrophil cytoplasmic antibody (MPO-ANCA) associated vasculitis, which is a rare clinical entity in medical practice.
  
  
  METHODS
  A 35-year-old female of Asian origin was admitted to our hospital due to complaints of Raynaud's phenomenon, myalgia, arthralgia and fatigue. The patient was diagnosed as MCTD in the out-patient department 8 months prior to admission based on Alarcon-Segovia classification criteria of Raynaud's phenomenon, myalgia, arthralgia and a high anti-U1 ribonucleoprotein antibody level. Interstitial lung disease was determined by chest computed tomography. Renal biopsy was performed because of marked proteinuria on 24 h urine collection. Histopathological examination revealed glomerulonephritis with fibrocellular/cellular crescents, in which moderate staining of IgM was shown by direct immunofluorescence. She was tested positive for myeloperoxidase antineutrophil cytoplasmic antibody.
  
  
  RESULTS
  High dose of methylprednisolone (500 mg/d for 3 days) was started intravenously when the results of renal biopsy were obtained. Oral prednisone and intravenous cyclophosphamide therapy (0.8 g/month) were continued for 12 months. Daily urinary protein loss decreased dramatically and serum creatinine was maintained at a normal level.
  
  
  CONCLUSIONS
  Corticosteroids and cyclophosphamide are effective in the treatment of MPO-ANCA associated glomerulonephritis in MCTD.
authors.affiliation: Department of Rheumatology, First Affiliated Hospital of the Medical School of Xi'an Jiaotong Universtiy, Xi'an 710061, China.
authors.forename: Yining
authors.initials: Y
authors.lastname: Sun
authors.forename: Lan
authors.initials: L
authors.lastname: He
authors.forename: Xiaohong
authors.initials: X
authors.lastname: Lü
authors.forename: Lingfei
authors.initials: L
authors.lastname: Mo
authors.forename: Jing
authors.initials: J
authors.lastname: Zhang
mesh_terms: D000328:Adult; D019268:Antibodies, Antineutrophil Cytoplasmic; D003520:Cyclophosphamide; D005260:Female; D005921:Glomerulonephritis; D006801:Humans; D008775:Methylprednisolone; D008947:Mixed Connective Tissue Disease; D009195:Peroxidase; D011507:Proteinuria
chemical_list: D019268:Antibodies, Antineutrophil Cytoplasmic; D003520:Cyclophosphamide; D009195:Peroxidase; D008775:Methylprednisolone