Liver disease referrals to an urban, hospital-based hepatology outpatient clinic over the past 25 years

Unconjugated hyperbilirubinemia may exacerbate certain underlying chronic liver diseases

BACKGROUND: Negative correlations have been described between elevated serum unconjugated bilirubin levels and the prevalence/severity of various chronic inflammatory conditions. Whether a similar association exists for patients with unconjugated hyperbilirubinemia (UCB) and underlying chronic liver diseases (CLD) has yet to be reported. The aim of this study was to document hepatic necro-inflammatory disease activity and fibrosis in CLD patients with and without UCB and otherwise normal liver function tests (albumin and INR). METHODS: Necro-inflammatory disease activity was assessed by serum aminotransferase levels and fibrosis by APRI and FIB-4 calculations. UCB patients were matched 1:2 by age, gender, and underlying CLD to patients with normal bilirubin levels. RESULTS: From a database of 9,745 CLD patients, 208 (2.1%) had UCB and 399 served as matched controls. Overall, UCB patients had significantly higher serum aminotransferase levels, APRI, and FIB-4 scores. The differences were driven by patients with underlying chronic viral or immune mediated liver disorders rather than non-alcoholic fatty liver disease, alcohol-related liver disease, or 'other' CLDs. CONCLUSIONS: These results suggest UCB is associated with increased rather than decreased hepatic necro-inflammatory disease activity and fibrosis in patients with certain CLDs.

Molecular epidemiology and clinical characteristics of hepatitis D virus infection in Canada

Background & Aims

HDV affects 4.5-13% of chronic hepatitis B (CHB) patients globally, yet the prevalence of HDV infection in Canada is unknown. To investigate the prevalence, genotype, demographics, and clinical characteristics of HDV in Canada, we conducted a retrospective analysis of (1) HDV antibody and RNA positivity among referred specimens, and (2) a cross-sectional subset study of 135 HDV seropositive +/-RNA (HDV+) patients compared with 5,132 HBV mono-infected patients in the Canadian HBV Network.

Methods

Anti-HDV IgG-positive specimens collected between 2012 and 2019 were RNA tested and the genotype determined. Patients enrolled in the Canadian HBV Network were >18 years of age and HBsAg-positive. Clinical data collected included risk factors, demographics, comorbidities, treatment, fibrosis assessment, and hepatic complications.

Results

Of the referred patients, 338/7,080 (4.8%, 95% CI 4.3-5.3) were HDV seropositive, with 219/338 RNA-positive (64.8%, 95% CI 59.6-69.7). The HDV+ cohort were more likely to be born in Canada, to be White or Black/African/Caribbean than Asian, and reporting high-risk behaviours, compared with HBV mono-infected patients. Cirrhosis, complications of end-stage liver disease, and liver transplantation were significantly more frequent in the HDV+ cohort. HDV viraemia was significantly associated with elevated liver transaminases and cirrhosis. Five HDV genotypes were observed among referred patients but no association between genotype and clinical outcome was detected within the HDV+ cohort.

Conclusions

Nearly 5% of the Canadian HBV referral population is HDV seropositive. HDV infection is highly associated with risk behaviours and both domestic and foreign-born patients with CHB. HDV was significantly associated with progressive liver disease highlighting the need for increased screening and surveillance of HDV in Canada.

Lay summary

Evidence of HDV infection was observed in approximately 5% of Canadians who were infected with HBV referred to medical specialists. HDV-positive patients were more likely to be male, born in Canada, or White or Black/African/Caribbean compared to Asian, and to have reported high-risk activities such as injection or intranasal drug use or high-risk sexual contact compared with patients infected with only HBV. Patients infected with HDV were also more likely to suffer severe liver disease, including liver cancer, compared with HBV mono-infected patients.