The Transmission Routes and Serum ALT Levels in Relation to Hepatitis C, Hepatitis B Virus Infection among Intravenous and non-Intravenous Drug Abusers

• Main Authors: Chang Chai-Jan, 張家禎
• Other Authors: Liu, Hong-Wen
• Format: Others
• Language: zh-TW
• Published: 2000
• Online Access: http://ndltd.ncl.edu.tw/handle/30139831611574721585

博士 === 高雄醫學大學 === 醫學研究所 === 88 === A seroepidemiology surrvey of anti-HCV, hepatitis B virus markers, and liver function among drug abusers in southern Taiwan was conducted. During the peroid from October 1994 to February 1996, a total of 935（899 males, 36 females）drug abusers from Kaohsiung Narcotic Abstention Institute and Kaohsiung Prison. The prevalence of anti-HCV antibody was 29.1% among male drug abusers and 19.4% among female drug abusers. The seroprevalence of anti-HCV antibody was 66.4% among intravenous drug abusers (IVDU) and 14.4% among non-intravenous drug abusers (non-IVDU). Intravenous drug use, a history of hepatits, having tattoos, and age were independently related to HCV seropositivity among drug abusers. The prevalence of anti-HCV antibody concentrations significantly increased (10.8-fold) with intravenous drug abuse and with having tattoos (1.7-fold). Among 247 intravenous male drug abusers, age and duration of drug use were independently related to HCV seropositivity. Seroprevalence rate for HCV in the IVDU group increased with increasing duration of injection use within the first seven years of drug use. However, the steepest trajectory in seroprevalence of HCV infection occurred within the first four months. According to univariate analysis in our study, the number of lifetime IVDU sex partners and frequency of condom use were found to be significantly associated with HCV infection, however, were not reached significantly in logistic regression analysis. Age was an indepentent risk factor of HCV infection, which was significantly associated with sexual behavior among the IV drug users. This would suggest that sexual transmission may still occur, albeit infrequently. The positive rates of HBsAg, anti-HBs, and anti-HBc were 21.2%, 70.2%, and 86.5%, respectively. The prevalence of HBV infection among intravenous drug abusers (96.8%) was significantly higher than among non-intravenous subjects (92.9%). In the pattern of combination of the three markers with 30 years of age as a border, the HBsAg(-), anti-HBs(+), anti-HBc(+) combination was more frequent under 29 years of age, however, the HBsAg(+), anti-HBs(-), anti-HBc(+) combination and all positive combination were more over 30 years of age. The frequency of HBV infection with serum anti-HBc negative was 8.4% among the intravenous drug abusers. Drug abusers with HBsAg or anti-HCV had higher serum aspartate aminotransferase (AST) and alanine aminotransferase (ALT) levels than those without HBsAg and anti-HCV. The pervalence of raised ALT and AST (>35 IU/L) in the HCV-positive group was more significant than in the negative group, while the HBsAg-positive group did not reach statistical significance. Among the HCV-positive group, ALT levels are more closely associated with HCV infection than AST levels. These findings suggest that hepatitis C virus may be mainly transmitted by the parenteral route among drug abusers in southern Taiwan. Due to the high rate of HCV infection among drug abusers, investigation of high-risk behavior should be routine in this group. To prevent HCV infection, emphasis on the use of sterile needles and aseptic procedures in tattooing is important in Taiwan. A high frequency of HCV infection was also found among short-term injectors, which indicated that early risk reduction intervention was an important measure in moderating HCV infection. Our findings suggest that horizontal transmission may be considered a possible reason for the significantly higher rate of HBV infection among intravenous drug abusers. Our sutdy also found that there may be an "immune incompetence" in intravenous drug abusers incapable of producing antibodies to hepatitis B core antigen. Due to the changes of combination of these three serum HBV markers and high prevalence rate of HBV infection among intravenous drug abuseres, investigation of serum HBV markers and liver function should be emphasized in these subjects. Our results indicated that HCV infection plays an important role in the etiology of raised ALT activity among drug abusers, while HBV infection plays a minor role. ALT screening still remains a simple and valuable method in the early recognition of HCV infection. The results of our study suggest that HCV superinfection in patients with chronic HBV infection may suppress or terminate the HBV carrier state among non-intravenous drug abusers. In addition, liver disease appeared to be more severe in patients with HCV infection alone than in patients with concurrent HBV and HCV infections. This means that a suppressive action between hepatitis B and C viruses may occur in dual infection with both viruses.