Pyogenic Andersson Lesion in a Patient With Ankylosing Spondylitis

Area of Science:

• Rheumatology and Infectious Diseases: Investigating the intersection of autoimmune inflammatory conditions and microbial infections.

Background:

• Andersson lesions (AL) are a rare spinal complication typically associated with long-standing ankylosing spondylitis (AS).
• The etiology of AL is multifactorial, with repetitive trauma and chronic inflammation being the most cited causes.
• Infectious causes of AL are considered extremely rare, with no prior reports of positive bone biopsy cultures.

Observation:

• A unique case of a pyogenic Andersson lesion (AL) in a patient with ankylosing spondylitis (AS) is presented.
• Histopathological examination revealed chronic inflammation, but importantly, bone biopsy cultures yielded positive microbial growth.
• This contrasts with typical AL presentations, which are generally non-infectious.

Findings:

• The identification of a pyogenic source in an Andersson lesion (AL) is a novel finding.
• Positive cultures from the bone biopsy confirm an infectious etiology in this specific case of AL associated with AS.
• This case challenges the prevailing notion that ALs are solely due to mechanical or non-infectious inflammatory processes.

Implications:

• The findings suggest that infectious etiologies should be considered in the differential diagnosis of Andersson lesions (AL), particularly in patients with ankylosing spondylitis (AS).
• This case may necessitate a re-evaluation of diagnostic and treatment strategies for AL, potentially including antimicrobial therapy.
• Further research is warranted to explore the prevalence and clinical significance of infectious causes in AL.