Two consecutive deep sinus tract cultures predict the pathogen of osteomyelitis

Area of Science:

• Orthopedics
• Infectious Diseases
• Medical Microbiology

Background:

• The diagnostic value of non-bone microbiological cultures for osteomyelitis with sinus tracts remains unclear.
• Accurate pathogen identification is crucial for effective osteomyelitis treatment.

Purpose of the Study:

• To determine the concordance between deep sinus tract cultures and bone cultures in diagnosing osteomyelitis with a cutaneous fistula.
• To evaluate the diagnostic accuracy of sinus tract cultures compared to bone biopsy.

Main Methods:

• A prospective diagnostic trial involving 141 patients with osteomyelitis and a cutaneous sinus tract.
• Four microbiological samples were collected: two sinus tract cultures (A-1, A-2), a bone biopsy through the tract (B), and a bone biopsy from an uninfected area (C, gold standard).

Main Results:

• High concordance (96%) was observed between sinus tract cultures (A) and the gold standard (C) when both yielded the same microorganism.
• Sensitivity, specificity, and accuracy for identical sinus tract culture infections were 91%, 86%, and 90%, respectively.
• Accuracy was higher in monomicrobial (94.3%) compared to polymicrobial (78.9%) infections.

Conclusions:

• Two concordant sinus tract cultures with bone contact can accurately predict the causative pathogen in monomicrobial osteomyelitis.
• This method offers a reliable non-bone culture approach for diagnosing specific types of osteomyelitis.