Hepatitis B (bodily fluids, 90 day incubation period)

🦠 Hepatitis B – Overview for NP Students

🧬 What Is It?

Hepatitis B virus (HBV) is a DNA virus that infects the liver, causing inflammation. It can lead to acute or chronichepatitis, cirrhosis, liver failure, and hepatocellular carcinoma (HCC).

  • Part of the Hepadnaviridae family

  • Spread through blood and body fluids

🔄 Transmission Routes (CHILD mnemonic)

Mode

Examples

Childbirth

Perinatal (mother to child) – especially in endemic areas

High-risk sex

Unprotected sex, MSM, multiple partners

Iv drug use

Needle sharing, unsafe injections

Living with infected person

Household contact (less common in adults)

Dialysis / healthcare

Occupational exposure, needlesticks

📊 Epidemiology

  • ~257 million people live with chronic HBV worldwide

  • In the U.S., most new cases occur in unvaccinated adults

  • Perinatal transmission leads to 90% risk of chronic infection (vs ~5% in adults)

🧪 HBV Serology Simplified

Marker

What it Means

HBsAg (Surface Antigen)

Active infection (acute or chronic)

Anti-HBs (Surface Antibody)

Immunity (past infection or vaccination)

Anti-HBc (Core Antibody)

Past or current infection (not from vaccine)

IgM anti-HBc

Acute infection

HBeAg

High infectivity

Anti-HBe

Lower infectivity

HBV DNA

Viral load (used to monitor replication and treatment response)

🧠 Clinical Phases

  1. Acute Hepatitis B

    • May be asymptomatic or cause fatigue, jaundice, nausea, RUQ pain

    • Elevated LFTs, positive HBsAg, IgM anti-HBc

    • Usually resolves in adults

  2. Chronic Hepatitis B (HBsAg > 6 months)

    • Persistent infection with risk of cirrhosis and HCC

    • May be immune tolerant, inactive carrier, or active hepatitis

🧑‍⚕ NP Role in Screening & Diagnosis

📋 Who to Screen?

  • People born in endemic regions (e.g. Asia, Africa)

  • Pregnant women (universal)

  • People who inject drugs

  • MSM

  • HIV or HCV-positive patients

  • Household contacts of HBV-positive individuals

📊 Labs to Order:

  • HBsAg, anti-HBs, anti-HBc (initial screen)

  • If positive: check HBeAg, anti-HBe, HBV DNA, LFTs

💊 Management

🧾 Acute HBV:

  • Supportive care

  • Monitor LFTs and symptoms

  • Rarely needs antiviral therapy unless fulminant hepatitis

📅 Chronic HBV:

  • Refer to GI or hepatology

  • Consider antiviral therapy (e.g., tenofovir, entecavir) if:

    • Elevated ALT

    • High HBV DNA

    • Evidence of liver damage (biopsy/fibroscan)

🛡 Monitor for:

  • Cirrhosis (LFTs, platelets, imaging)

  • Hepatocellular carcinoma: Ultrasound every 6 months if cirrhotic or high-risk

💉 Prevention

✅ Vaccine:

  • 3-dose series (0, 1, 6 months) OR newer 2-dose option (e.g., Heplisav-B)

  • Universal newborn vaccination

  • Pre-exposure vaccination for:

    • Healthcare workers

    • High-risk adults (e.g., IV drug users, MSM)

👶 Birth Protocol:

  • If mom is HBsAg-positive:

    • Give HBIG + HBV vaccine to infant within 12 hours of birth

🗣 Patient Education

  • HBV is not spread through casual contact (hugging, kissing, coughing)

  • Use condoms and avoid sharing needles/razors

  • Do not donate blood

  • Alcohol avoidance is critical to prevent liver damage

  • Importance of regular follow-up to monitor liver health

  • Vaccinate household and sexual contacts

✅ Key Clinical Pearls

  • HBsAg + Anti-HBc IgM = acute infection

  • HBsAg > 6 months = chronic infection

  • Anti-HBs only = vaccinated

  • Anti-HBs + Anti-HBc = recovered from infection

  • All pregnant women should be screened at first prenatal visit