title: Elevated serum immunoglobulin G titers against Chlamydia pneumoniae in primary open-angle glaucoma patients without systemic disease.
abstract: OBJECTIVE
  To determine if Chlamydia pneumoniae infection is associated with primary open-angle glaucoma (POAG).
  
  
  METHODS
  Consecutive patients with newly diagnosed primary POAG attending the Glaucoma clinic of Keio University Hospital between June 2007 and January 2008 were considered for inclusion in this prospective case-control study. Forty consecutive POAG patients and 41 normal healthy individuals as a control population met the inclusion criteria. The exclusion criteria for both groups were; taking steroids or immunosuppressive agents, smoking, and history of any acute or chronic systemic disease including stroke, heart attack, diabetes mellitus, hypertension, asthma, and autoimmune diseases. The serum was analyzed for C. pneumoniae and C. trachomatis immunoglobulin G antibody titers by enzyme-linked immunosorbent assay. Seroactivity to each antigen between case and control groups was evaluated by Mann-Whitney U test.
  
  
  RESULTS
  The age, male/female ratio, and intraocular pressure of the cases and control groups were not significantly different. Immunoglobulin G titers for C. pneuemoniae was significantly higher in patients with POAG than in controls (P=0.009). The titers to C. trachomatis were not significantly different between the 2 groups (P=0.99).
  
  
  CONCLUSIONS
  The results suggest that higher C. pneumoniae titers are associated with POAG. If confirmed, this may indicate either a common factor that causes susceptibilities to both glaucoma and C. pneumoniae infection or that C. pneumoniae may be a causal factor for developing POAG.
authors.affiliation: Department of Ophthalmology, Keio University School of Medicine, Tokyo, 160-8582, Japan.
authors.forename: Kenya
authors.initials: K
authors.lastname: Yuki
authors.forename: Itaru
authors.initials: I
authors.lastname: Kimura
authors.forename: Daisuke
authors.initials: D
authors.lastname: Shiba
authors.forename: Yutaka
authors.initials: Y
authors.lastname: Imamura
authors.forename: Kazuo
authors.initials: K
authors.lastname: Tsubota
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D000907:Antibodies, Bacterial / Q000097:blood*; D016022:Case-Control Studies; D002692:Chlamydia trachomatis / Q000276:immunology; D023521:Chlamydophila Infections / Q000276:immunology; D016993:Chlamydophila pneumoniae / Q000276:immunology*; D004797:Enzyme-Linked Immunosorbent Assay; D005260:Female; D005902:Glaucoma, Open-Angle / Q000276:immunology* / Q000382:microbiology; D006801:Humans; D007074:Immunoglobulin G / Q000097:blood*; D007429:Intraocular Pressure; D008297:Male; D008875:Middle Aged; D011446:Prospective Studies; D012307:Risk Factors; D014141:Trachoma / Q000276:immunology; D014792:Visual Acuity
chemical_list: D000907:Antibodies, Bacterial; D007074:Immunoglobulin G