Identification of patients with HBV and HCV infection in the primary care setting: Pre-defined risk scenarios are a better screening strategy than elevated ALT values
Aims: Elevated ALT values are used as trigger to screen for hepatitis B (HBV) and hepatitis C (HCV) virus infection. However, both infections can present with ALT values within normal limits. Treatment guidelines additionally define scenarios with increased risk for both diseases. We evaluated the relevance of guideline defined risk scenarios in clinical practice.
Methods: An HBsAg and anti-HCV (Architect, Abbott) screening was implemented in a routine check-up performed by primary care physicians. A questionnaire covering 15 risk scenarios defined by the German hepatitis C guidelines was distributed to all patients. HBsAg, anti-HCV and ALT were analyzed at a central lab. We applied 2-sided Chi square statistics.
Results: 6052 patients were screened by 43 primary care physicians within 4 months. The HBsAg and anti-HCV prevalence was 0.4% and 0.8% without any co-infection. The mean age of HBV and HCV cases was 58 (38–82) and 54 (34–90) years. Infections were previously known in 3/27 (11%) and 19/51 (37%) individuals, elevated ALT values were only present in 26% and 39% of HBV and HCV patients.
Compared to uninfected individuals, the following risk factors were significantly more often reported in patients with viral infections:
HBV: migration background (n=9/27 vs. 611/5642; p=0.002)
HCV: Elevated ALT (n=30/48 vs. 771/5570; p=0.002), fatigue (n=24/48 vs. 1689/5569; p=0.004), blood transfusion (n=10/47 vs. 384/5568; p=0.001), piercing (n=6/45 vs. 233/5634; p=0.011), tattoo (n=18/47 vs. 559/5651; p<0.001), drug abuse (n=25/48 vs. 279/5599; p<0.001), dialysis (n=3/46 vs. 68/5500; p=0.021)
Risks not reported more frequently were medical profession, organ transplantation, surgery, family member with hepatitis, MSM, promiscuity, and traveling.
In an analysis, which was the best screening-strategy to identify HBV and HCV infections, elevated ALT only, analysis of the complete risk scenario questionnaire, combination of ALT elevation and questionnaire, and combination of ALT elevation with only the above mentioned main risk factors were defined as four different approaches. HBV patients were identified in 26%, 46%, 46%, and 35% of cases, respectively. HCV patients were identified in 39%, 76%, 76%, and 61% of cases, respectively.
Conclusion: The primary care setting allows screening of large patient numbers within a short time period. Elevated ALT values as screening trigger miss the majority of HBV and HCV infections. A detailed analysis of risk scenarios may be the best approach to identify HBV and HCV patients.