Chronic hepatitis B virus (HBV) infection is a major worldwide health issue. It causes 1.5 million new cases and 820000 fatal mortalities every year. Increased serum HBV-deoxyribonucleic acid (DNA) levels are a risk factor for disease progression. Occult HBV infection (OBI) is a complex clinical condition characterized by the presence of Hepatitis B surface Antigen (HBsAg) and minimal viral replication.
The case report published in the medtigo Journal of Medicine underlines the clinical significance of the Occult hepatitis B infection (OHB) in patients with cryptogenic cirrhosis and recommends routine testing of HBV-DNA in HBsAg-negative patients to improve the diagnostic accuracy and treatment methods.
A 45-year-old man from Burie, Ethiopia, had a 2-month history of easy fatigability, progressive abdominal swelling, and loss of appetite. The patient had no history of sleep disturbances, hematemesis, changes in urine quality or color, or melena. Respiratory rate, blood pressure, pulse rate, and temperature were the vital signs. Abdominal examination showed splenomegaly and ascites.
Laboratory results showed a white blood cell count of 2.4 × 10³/µL, mean corpuscular volume of 97 fL, hemoglobin of 9 g/dL, and platelet count of 78 × 10³/µL. Liver function tests revealed increased transaminases, serum albumin was decreased to 3 g/dL, and total bilirubin was 0.9 mg/dL. Renal function was within normal limits, with serum creatinine levels of 0.8 mg/dL. Anti-hepatitis C virus (HCV) antibody, Hepatitis B surface Antigen, and human immunodeficiency virus (HIV) were negative through viral serology test. HBV-DNA test showed decreased level of viremia (15 IU/mL) and serum alpha-fetoprotein (AFP) (4.44 IU/mL). Abdominal ultrasonography showed severely nodular liver with uneven surface, typical cirrhosis, and no evidence of portal vein thrombosis and focal hepatic lesion. Echocardiography (ECG) found no abnormality. Upper gastrointestinal (GI) endoscopy found grade 3 esophageal varices, moderate portal hypertensive gastropathy, and red wale signs. Endoscopic variceal band ligation was performed, and the patient was scheduled for follow-up using the esophageal variceal band ligation method.
OHB is a common cause of cirrhosis with non-alcoholic steatohepatitis (NASH), alcohol, and anti-hepatitis C virus (HCV), with geographical variations. OHB is caused by the presence of HBV-DNA in the liver of patients with a low viral load (below 200 IU/mL) and negative HBsAg test results. Diagnosis of OHB is challenging because HBV-DNA is detected intermittently in the blood, and there is no standardized molecular test for viral load. OHB can have significant clinical consequences like transmission by organ transplantation or blood transfusion, reactivation during immunosuppression, rapid development of cirrhosis and liver disease, and elevated risk of hepatocellular carcinoma.
The best method for diagnosis is through extremely sensitive molecular methods, such as polymerase chain reaction and HBV nucleic acid amplification testing. A systematic review found that an elevated risk of hepatocellular carcinoma (HCC) with OHB, with an odds ratio (OR) of 6.1 for the retrospective study and 2.9 for the prospective study. It is necessary to investigate the potential of OHB in patients who have a negative HBsAg test result along with cirrhosis.
Reference: Zelalem M. Occult Hepatitis B Infection in a Decompensated Cirrhosis Patient. medtigo J Med. 2025;3(2):e30623214. doi:10.63096/medtigo30623214
