01 Set Emerging genotype E of Hepatitis B Virus in Young African migrants in Rome: new clinical and virological settings.

Vincenzo Malagnino

NTRODUCTION: Chronic Hepatitis B (CHB) represents a major health problem with approximately 400 million carriers worldwide. In particular, Africa represents the second area of the world for prevalence of Hepatitis B Virus (HBV) infection and 2% of deaths are caused by Hepatocellular Carcinoma (HCC) or Cirrhosis. Few data about distribution, clinical evolution and treatment response of Africans genotypes are available.
METHODS: A cohort of 358 west-African patients coming from 20 migrant’s shelters in Rome was screened for HBV, HCV, HIV, syphilis and tuberculosis in the service of Infectious Diseases of Tor Vergata Polyclinic from November 2013 to May 2015.
RESULTS: The 358 patients were all males with a median age [IQR] of 24 [21-27] years. One hundred and ninety-one patients (61%) presented a past or ongoing HBV infection, 80 (25,5%) were positive to Mantoux skin test (3 patients [0,9%] evidenced active tuberculosis), 5 (1,5%) resulted anti-HCV positive and 4 (1,27%) anti-HIV and VDRL positive.One hundred and forty-one (73,8%) out of 191 HBV-exposed patients were HbsAg-negative (58 presented anti-Hbc and anti-Hbs, 83 were anti-Hbc-alone), whereas 50 (26,1%) were HbsAg-positive. All HBsAg-positive subjects were drug-naive, the median [IQR] HBV-DNA was 3.0[2,3-3,6] logIU/mL, and quantitative HbsAg was 10311 IU/mL [2282-20957]. No confection with HDV, neither elevation of transaminases was found. One case was diagnosed with HCC.
The analysis of viral genotype (available for 42 out of 54 [77,7%] patients) evidenced a high prevalence of genotype E (34/42 [89,2%] patients), all carrying the constitutive HBsAg mutation T140S, known to be associated with immunological escape. Seven patients harboured HBV genotype A, naturally characterized by two immune-escape mutations: T131N and Y100C. Only one patient was infected by HBV genotype D1.
CONCLUSIONS: Our results demonstrated a high prevalence of chronic HBV infection associated with E genotype in a population of young west-African people. The virus strains isolated from the majority of the subjects showed T140S mutation associated with immunological escape. Despite the low level of viremia, the high titer of HbsAg characterizing these patients requires a particular monitoring since it could be a marker of HBV persistence and increased risk of HCC progression