Study of the pathogenesis and prognosis of HBsAg carriers: Natural decrease of HBV surface antigen titer in HBsAg carrier

Among the 832 HBsAg carriers who have been observed continuously (average observation periods 4.3 yrs.), 79 cases showed decrease of HBsAg titer under 26 by R-PHA. By critical analytical method "person year (P.Y.)", this tendency designated the highest peak at 41-44 years old (9.5% P.Y.) and the lowest peak at 31-34 year old (1.0% P.Y.). During the observation periods, 28 patients showed negative of HBsAg and 3 of them obtained anti-HBs. Decreased cases of HBsAg titer increased in elder patients and those showed anti-HBe positive during the observation period, and the result of the liver function tests was stable in those patlents. From these results, it is speculated that decrease of HBsAg titer may be ominous of HBsAg negative and the liver function tests are stable in this condition.