Which marker indicates active hepatitis B infection?
Answer and explanation
Correct answer: A. Positive HBsAg
- Step 1: HBsAg is the surface antigen found in acute and chronic infection.
- Step 2: Anti-HBs alone indicates immunity from vaccination.
Answer
Positive HBsAg.
Practise more Adult Internal Medicine and Emergency Protocols.
Free questions with an explanation for every one, and full timed Lebanese Medical Colloquium (Colloquium Liban) mock tests.
More Adult Internal Medicine and Emergency Protocols questions
- A 62-year-old male with hypertension presents with 2 hours of crushing substernal chest pain. The ECG reveals 3 mm ST elevation in leads II…
- A 45-year-old female presents with acute severe epigastric pain radiating to the back and vomiting. Serum lipase is 1,200 U/L (normal < 60 U…
- A 28-year-old male with type 1 diabetes presents with nausea, vomiting, Kussmaul respirations, and lethargy. Blood glucose is 480 mg/dL, art…
- A 70-year-old male with long-standing severe COPD presents with increased dyspnea, purulent sputum, and drowsiness. ABG reveals pH 7.28, PaC…
- A 55-year-old female presents with fever, right upper quadrant pain, and jaundice (Charcot's triad). BP is 80/50 mmHg and she is confused (R…
- A 35-year-old male presents with sudden-onset severe headache ('worst headache of my life'). Non-contrast head CT performed 3 hours after on…