ISOLATED HEPATITIS B CORE DISEASE AND OCCULT HEPATITIS B AMONG DIALYSIS COHORT IN MALAYSIA – A SINGLE CENTRE STUDY

Introduction:

Occult Hepatitis B infection (OBI) refers to the presence of replication-competent HBV DNA, including the episomal covalently closed circular DNA (ccDNA), within the liver and/or at low levels in serum (<104 copies/mL) in HBsAg-negative individuals. OBI has been associated with an increased risk of HBV reactivation and transmission, particularly in immunocompromised patients. Patients with OBI also can act as reservoirs for HBV transmission. This study aims to evaluate the efficacy of current virological testing methods on OBI in dialysis populations, and to study the correlation between OBI and Anti-HBsIgG levels.

Methods:

A retrospective study at University Malaya Medical Center (UMMC), investigating patients who attended the dialysis unit from 1st January 2019 to 30th June 2024[u1] . Patients who were younger than18 years old, has known chronic Hepatitis B infection, did not have End Stage Kidney Disease (ESKD) or had incomplete data were excluded. Virology testing for Hepatitis B such as HBsAg, Anti-HBsAg, Anti-HBc IgG and HBV DNA were included. Patients’ demographics, clinical, biochemical information were also recorded from Electronic Medical Record (EMR). Data collected was analyzed using SPSS v29.0.2.0, using mean and standard deviation for parametric test, median and interquartile range for non-parametric test. P value of <0.05 was considered statistically significant.

Results:

A total of 952 patients were screened and 662 patients were included. They were predominantly males (59.1%), Malay ethnic (45.2%) with the mean age of 62.8±13.7. Diabetes mellitus was the main cause of ESKD (68.3%), followed by hypertension (16.0%) and glomerulonephritis (7.1%).

Among these patients, 273 (41.2%) had positive Anti-HBc IgG. HBV DNA was detected in 19 (7.0%), not detected in 186 (68.1%) and not tested in 68 (24.9%) patients. Among those with positive HBV DNA, 9 (47.4%) had positive Anti-HBs IgG (>10 mIU/mL) while 10 (52.6%) had negative Anti-HBs IgG. In HBV DNA negative patients, 159 (85.5%) had positive Anti-HBs IgG, while 27(14.5%) had negative Anti-HBs IgG. HBV DNA levels ranged from 10 to 35,560 copies/mL. During follow-up, none of OBI patients develop positive HBsAg.

Among patients with positive for both Anti-HBc IgG and HBV DNA, 3 (15.8%) had a Anti-HBs IgG level of more than100 mIU/mL whereas for patients with positive Anti-HBc IgG positive but negative HBV DNA, 105 (56.5%) had a Anti-HBs IgG level of more than100 mIU/mL. There was no significant difference (p>0.05) between demographic characteristics or liver function tests among HBV DNA positive and negative groups.

Conclusions:

Our study showed that ESKD patients had 41.2% of isolated hepatitis B core disease and 7% of OBI incidence. About half (52.6%) of OBI patients had positive Anti-HBs IgG, suggesting that utilising Anti-HBs IgG alone does not entirely exclude occult infection. These highlight the limitations of relying solely on standard Hepatitis B serological markers and underscore the need for comprehensive screening for Anti-HBc IgG and HBV DNA in dialysis patients. This proposes the need to update clinical guidelines and implement rigorous screening protocols for earlier OBI detection and prevent HBV transmission among dialysis patients.

I have no potential conflict of interest to disclose.

I did not use generative AI and AI-assisted technologies in the writing process.