2305 HBSAg Seroclearance and Seroconversion Among Male Filipino Americans With Chronic Hepatitis B

Abstract

INTRODUCTION: Worldwide prevalence of HBV infection, defined as presence of HBSAg is estimated at 257 million, and a 2009 study on HBV prevalence in the United States is estimated to be 2.2 million individuals. The chronic effects of HBV infection include cirrhosis and liver cancer and the disease burden impacts health care resources. Therefore, in 2009, the Centers for Disease Control has recommended HBV screening for patients who were born in geographic areas that has high HBV prevalence. The Philippines has approximately 8-12% HBV infection, and Filipino Americans account for a significant number of individuals migrating to the USA. HBSAg seroclearance (loss of HBSAg) and seroconversion (development of HBSAb) is described to be rare, and to our knowledge, has not been documented among patients who reside in the United States. In this case series, we describe our experience of 5 patients with this rare event. CASE DESCRIPTION/METHODS: Electronic medical records from our clinic Las Vegas Gastroenterology (Clark County, Las Vegas, NV) were retrospectively reviewed with ICD 9 and 10 codes (070.30, 070.32, B16.9, B19.10, B19.11). Of these we describe 5 HBSAg positive, HBeAg negative, HBeAb positive patients: 2 patients received treatment and 3 patients were treatment naive. All of these patients were of Asian descent (Filipino American), all males, with ages 45-55 years when initially seen in clinic. The 2 patients who received treatment, both had seroclearance while only 1 had seroconversion. Both patients were treated with TDF, with average treatment duration of 8 years prior to seroclearance. The 3 patients who were treatment naive all did not meet treatment criteria on presentation, and were followed for average duration of 6 years (3-8 years). All patients had spontaneous seroclearance and seroconversion. DISCUSSION: Our study describes HBSAg loss in patients with chronic HBV infection, which is relatively sparsely documented among chronic HBV patients in the United States. Interestingly, these patients were all males, all Filipino Americans and majority of the patients described in this case series were treatment naive. Further studies on the effect of gender, race and ethnicity are essentially in understanding the natural history of chronic HBV infection.