Aims: Despite successful implication of vaccination against HBV in Austria numbers of referrals due to chronic hepatitis B are increasing. This may partly be explained by increased awareness of the medical community of recent advances in antiviral therapy by development and availability of new nucleos(t)id analogues. The aim of this investigation was to evaluate epidemiological data, (pre-)treatment outcome and development of HBV resistance in patients with chronic hepatitis B seen at our center.
Patient and Methods: One hundred and nine patients (m/f=81/28), age: 40[19–77] years, median[range]) with chronic hepatitis B collected since 2004 were available for evaluation.
A retrospective data analysis concerning age, gender distribution, country of origin, HBV genotype (INNO-LiPA HBV Genotyping, Innogenetics), HBeAg status, HBV DNA (VERSANT® HBV DNA 3.0 Assay (bDNA)), therapy management and outcome was done.
Results: 19/109 patients (17%) were of Austrian origin, 34 (31%) were Turkish, 23 (21%) came from the Balkan states and 15 patients (14%) from Far East. The remaining patients were from Africa, Afghanistan and South America. 61 (56%) were HBeAg negative and 87 (70%) patients showed an initial virus load <107 U/ml. The HBV genotype was available in 41 patients (D=23 (21%); A=5 (4.6%); B=4 (3.7%); C=2 (1.8%); E=6 (5.5%)). The most common first line therapy was either 100mg/day Lamivudine (Zeffix®) (n=55, 50.5%) or pegylated interferon-alpha2a (180! g PEGASYS®/week for 48 weeks) (n=53, 48.7%).
Lamivudine resistance (LAM-R, M204V/I) was observed in 8 (20%) out of 40 patients tested after one year and in 14 (35%) patients after 2 years. Development of LAM-R was associated with high baseline viral load. In case of emergence of lamivudine resistant strains Adefovir (Hepsera®, n=16) Tenofovir (Viread®, n=20) or Entecavir (Baraclude®, n=5) was used. Virological response defined as undetectable HBV DNA (<351 U/ml) was seen in 34 (31.2%) patients. Partial virological response (<10000 U/ml) was achieved in additional 22 (20.2%) patients. HBs“antiHBs seroconversion was achieved in 3 patients (2 Lamivudine, 1 peginterferon-alpha). Out of 48 HBeAg positive patients 11 (22.9%) reached HBe“antiHBe seroconversion.
Conclusion: Male, middle aged immigrants represent the majority of patients with chronic hepatitis B referred to our center. The predominant HBV genotype was genotype D. A virologic response was achieved in half of the patients. Particularly, in patients with high baseline viral load, lamivudine resistant strains emerged frequently. Rigorous testing for genotypic LAM-R may increase the number of patients needing an adequate rescue strategy in the future.
