title: [Complement activity among individuals at a ground self-defense force base].
abstract: OBJECTIVE
  This study aims to examine the distribution of hemolytic complement activity, the prevalence of hypocomplementemia and the disorders causing hypocomplementemia among individuals taking part in a mass screening program.
  
  
  METHODS
  The subjects consisted of 1340 male Japanese participating in a mass screening program at a Ground Self-Defense Force base in Asaka. We measured the hemolytic complement activity (CH50) after overnight fasting. The CH50 levels for hypercomplementemia and hypocomplementemia were defined as those outside the range of mean +/- 2 SD, respectively. We next measured the concentration of complement components: CIq, C4, B, C3, C5, C9, and C1-inhibitor for men with hypocomplementemia. Rheumatoid factor, ANA, HBsAg, HbsAb, and HCVAb were also measured.
  
  
  RESULTS
  The mean +/- SD of age was 43.7 +/- 5.7. The CH50 levels ranged from 7.2 to 66.4 U/ml (mean +/- SD = 37.1 +/- 4.0 U/ml). Twenty-one and 37 men were classified as having hypocomplementemia (CH50 < 29.1 U/ml) and hypercomplementemia (CH50 > 45.1 U/ml), respectively. The age of the individuals with hypocomplementemia was 43.9 +/- 5.6 (Mean +/- SD) years. Three men with C9 deficiencies, 2 men with C5 deficiencies and 7 men with cold activation were identified among the 21 hypocomplementemic men. Three hepatitis C and 2 hepatitis B patients were also found among the 21 hypocomplementemic men. Other disorders found among the hypocomplementemic men were 3 glomerulonephritides and 1 possible SLE.
  
  
  CONCLUSIONS
  We examined the distribution of CH50 levels in 1340 adult male Japanese. We identified 21 men with hypocomplementemia, and also found 5 cases of complement component deficiencies among 21 hypocomplementemic men. In addition the measurement of the complement activity may have also helped detect the presence of hepatitis, hypocomplementemic glomerulonephritis and collagen disease at an early stage.
authors.affiliation: Department of Public Health, National Defense Medical College, Namiki 3-2, Tokorozawa, Saitama, 359-8513, Japan.
authors.forename: H
authors.initials: H
authors.lastname: Tanaka
authors.forename: K
authors.initials: K
authors.lastname: Yamakami
authors.forename: S
authors.initials: S
authors.lastname: Honjo
authors.forename: T
authors.initials: T
authors.lastname: Umeda
authors.forename: K
authors.initials: K
authors.lastname: Wakabayashi
authors.forename: T
authors.initials: T
authors.lastname: Oda
authors.forename: N
authors.initials: N
authors.lastname: Yoshizawa
mesh_terms: D000328:Adult; D003095:Collagen Diseases / Q000453:epidemiology; D015941:Complement Hemolytic Activity Assay; D003165:Complement System Proteins / Q000172:deficiency*; D015432:Glomerulonephritis, Membranoproliferative / Q000453:epidemiology; D006509:Hepatitis B / Q000453:epidemiology; D006526:Hepatitis C / Q000453:epidemiology; D006801:Humans; D007564:Japan / Q000453:epidemiology; D008297:Male; D008403:Mass Screening; D008875:Middle Aged; D008889:Military Personnel / Q000706:statistics & numerical data*; D015995:Prevalence
chemical_list: D003165:Complement System Proteins