skip to main content

Primary SBP Prophylaxis — SCE Infectious Diseases MCQ

Instant feedback + full explanation. One question, done properly.

ModerateHepatitisPrimary SBP ProphylaxisSCE Infectious Diseases

A 45-year-old man with decompensated cirrhosis and ascites (ascitic protein 10 g/L) has never had SBP. He is on no prophylactic antibiotics. According to guidelines, should primary SBP prophylaxis be offered?

Educational content. Not a substitute for clinical judgement or local policy.

Reveal the answer and explanation

Correct answer: CYes — Norfloxacin 400 mg daily (or Ciprofloxacin) is indicated for primary SBP prophylaxis when ascitic protein is <15 g/L plus additional risk factors

Primary SBP prophylaxis is indicated/should be offered in selected high-risk patients with cirrhosis and ascites before any first episode of SBP. This patient has decompensated cirrhosis with low ascitic protein: 10 g/L, which is below the high-risk threshold of 15 g/L (1.5 g/dL). Therefore he falls into the group for primary prophylaxis, after discussion of risks and local antimicrobial advice. The traditional regimen is norfloxacin 400 mg once daily; in UK practice ciprofloxacin is commonly used as an alternative where appropriate. The other options are incorrect: prophylaxis is not only secondary after a first SBP episode, not limited to transplant candidates, not never indicated, and the threshold is not <5 g/L.

Reference: NICE guideline NG50, Cirrhosis in over 16s: assessment and management, updated 2023 — section 1.3 Preventing spontaneous bacterial peritonitis: https://www.nice.org.uk/guidance/ng50/chapter/Recommendations