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Updated: Feb 9, 2026

Candidate Gene Testing in Clinical Cohort Studies with Multiplexed Genotyping and Mass Spectrometry
Published on: June 21, 2018
Clinical epidemiology of chronic viral hepatitis B: A Tuscany real-word large-scale cohort study
Cristina Stasi1, Caterina Silvestri1, Roberto Berni2
1Observatory of Epidemiology, Regional Health Agency of Tuscany, Florence 50141, Italy.
Aim:
To build a regional database of chronic patients to define the clinical epidemiology of hepatitis B virus (HBV)-infected patients in the Tuscan public health care system.
Methods:
This study used a cross-sectional cohort design. We evaluated chronic viral hepatitis patients with HBV referred to the outpatient services of 16 hospital units. Information in the case report forms included main demographic data, blood chemistry data, viral hepatitis markers, instrumental evaluations, and eligibility for treatment or ongoing therapy and liver transplantation.
Results:
Of 4015 chronic viral hepatitis patients, 1096 (27.3%) were HBV infected. The case report form was correctly completed for only 833 patients (64% males, 36% females; mean age 50.1 ± 15.4). Of these HBV-infected patients, 73% were Caucasian, 21% Asian, 4% Central African, 1% North African and 1% American. Stratifying patients by age and nationality, we found that 21.7% of HBV-infected patients were aged < 34 years (only 2.8% were Italian). The most represented routes of transmission were nosocomial/dental procedures (23%), mother-to-child (17%) and sexual transmission (12%). The most represented HBV genotypes were D (72%) and A (14%). Of the patients, 24.7% of patients were HBeAg positive, and 75.3% were HBeAg negative. Of the HBV patients 7% were anti-HDV positive. In the whole cohort, 26.9% were cirrhotic (35.8% aged < 45 years), and 47% were eligible for or currently undergoing treatment, of whom 41.9 % were cirrhotic.
Conclusion:
Only 27.3% of chronic viral hepatitis patients were HBV infected. Our results provide evidence of HBV infection in people aged < 34 years, especially in the foreign population not protected by vaccination. In our cohort of patients, liver cirrhosis was also found in young adults.
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