Discitis and sacroiliitis diagnosed 15 years after iatrogenic Mycobacterium xenopi inoculation

Area of Science:

• Infectious Diseases
• Orthopedic Surgery
• Mycobacteriology

Background:

• Atypical mycobacterial infections, particularly Mycobacterium xenopi, are uncommon causes of bone and joint infections.
• These infections can have a prolonged, indolent course, making early diagnosis challenging.
• A history of nosocomial infection during a previous surgical procedure is noted.

Observation:

• A patient developed discitis and sacroiliitis attributed to Mycobacterium xenopi.
• The patient had undergone percutaneous nucleotomy 15 years prior, during a known M. xenopi outbreak at the institution.
• Initial follow-up imaging (MRI) 15 years post-surgery did not reveal signs of discitis, which was confirmed on retrospective review.

Findings:

• This represents the first reported case of Mycobacterium xenopi discitis with secondary sacroiliitis in an immunocompetent individual.
• The slow-onset nature of atypical mycobacterial bone and joint infections is highlighted by the 15-year interval between potential exposure and diagnosis.
• The case underscores the diagnostic difficulties associated with rare, slow-growing pathogens in orthopedic infections.

Implications:

• Highlights the importance of considering rare pathogens like Mycobacterium xenopi in persistent or unusual bone and joint infections, even years after initial treatment or exposure.
• Suggests that atypical mycobacterial infections should be considered in the differential diagnosis of discitis and sacroiliitis, especially in patients with relevant exposure history.
• Emphasizes the need for vigilant long-term follow-up and potentially re-evaluation of imaging in cases of suspected indolent infections.