skip to main content

M. fortuitum Sternal Infection — SCE Infectious Diseases MCQ

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

HardTuberculosisM. fortuitum Sternal InfectionSCE Infectious Diseases

A 55-year-old man presents with a chronic draining sinus from his sternum. He underwent CABG 2 years ago. CT chest shows sternal non-union with peri-sternal fluid collection. Deep tissue cultures grow Mycobacterium fortuitum (a rapidly growing NTM). What treatment is required?

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

Reveal the answer and explanation

Correct answer: D — Surgical debridement plus combination antibiotics guided by susceptibility testing — M. fortuitum is typically susceptible to Amikacin, Ciprofloxacin, Co-trimoxazole, Imipenem, and Doxycycline; treatment for 6–12 months

Rapidly growing mycobacteria (RGM — M. fortuitum, M. abscessus, M. chelonae) cause surgical site infections, prosthetic device infections, and catheter-related infections. M. fortuitum is typically susceptible to Amikacin, Ciprofloxacin, Co-trimoxazole, Imipenem, and some tetracyclines — but NOT to standard anti-TB drugs or macrolides (unlike M. abscessus which has variable macrolide susceptibility). Treatment: surgical debridement PLUS at least 2 susceptible agents for 6–12 months. Hardware removal may be needed if foreign material is present.

Reference: BTS 2017 – NTM; ATS/IDSA 2020 – RGM treatment