Objective To study the distribution of antinuclear antibodies ( ANAs) in a healthy population and the significance of using ANAs screening test in medical examination .Methods The ANAs were measured by indirect immunofluorescence assay ( IIF) .The Western blot assay was used to detect fif-teen specific antibodies against auto-antigens .Results 3519 out of all 25 110 subjects showed ANAs titers>1∶100 , and among them male and female subjects were respectively accounted for 1143 and 2376 .1489 out of all subjects had ANAs titers >1∶320 , and among them male and female subjects were respectively accounted for 406 and 1083 .The positive rates of ANAs at different titers showed significant differences be -tween male and female subjects .Among subjects with ANAs titers >1∶320 , the number of male subjects showed a steady increase with the age , while the percentage of female subjects reached to two peaks during the periods of puberty and menopause .The fifteen specific antibodies were detected in 659 out of 1489 sub-jects with ANAs titers>1∶320 and anti-Ro-52 (14.2%) accounted for the majority , followed by anti-M2 (12.7%) and anti-SSA (9.6%).Conclusion ANAs can be detected among healthy population of all ages, but their distribution varied with gender and age .ANAs screening test is necessary for medical exami-nation of healthy population , especially for female during period of puberty or menopause .The population with positive ANAs should be followed-up closely and educated for the prevention of autoimmune diseases .

OBJECTIVETo explore the distribution of the main clinical symptoms and signs of primary biliary cirrhosis (PBC) in a population of individuals with positivity for anti-mitochondrial antibody-M2 (AMA-M2).

METHODSA total of 20 970 persons who participated in routine health examinations at our hospital were tested for presence and level of antinuclear antibodies (ANAs) using an indirect immunofluorescence (IIF) assay and of AMA-M2 by western blotting. The chi-square test was used for statistical analysis.

RESULTSTiters of ANAs more than 1:320 were detected in 1 243 of all the study participants, with 156 of those individuals having detectable AMA-M2.The overall rate ofAMA-M2 positivity was 0.74%, with a significantly higher rate among female subjects (males:0.3% (32/10 550) vs.females:1.2% (124/10 420); x2=55.85, P less than 0.05). Among the AMA-M2-positive population there were 66 cases of abnormal liver function, 58 cases of increased alkaline phosphatase, 72 cases of abnormal findings for routine blood testing, 47 cases of gallbladder disease history, 49 cases of diabetes history, 22 cases of allergy, 75 cases of abdominal discomfort, 38 cases of weakness, 3 cases of jaundice, and 11 cases of pruritus. There were significant differences between the AMA-M2-negative individuals and the AMA-M2-positive individuals.

CONCLUSIONAmong the general population, individuals with substandard states of health, such as those with abnormal findings in routine blood tests and abnormal liver function, should be screened for AMA-M2. This screening will facilitate early diagnosis of PBC and timely initiation of disease management, improving the patient's life quality of life and prolonging their life.

Biomarkers ; Blotting, Western ; Female ; Fluorescent Antibody Technique, Indirect ; Humans ; Liver Cirrhosis, Biliary ; metabolism ; Male ; Pruritus ; Quality of Life