Background: Pediatric osteomyelitis is a severe disease that requires early diagnosis and prompt treatment to minimize the potential risk of developing severe complications, including septic arthritis. Identifying clinical features and applying relevant diagnostic tools are necessary to yield an early diagnosis. Osteomyelitis may show various clinical presentations depending on the etiology, especially in children, making the diagnosis difficult. Therefore, a thorough clinical history, detailed physical examination, and a high index of suspicion are imperative to early diagnose this condition. One should be aware of the evolving epidemiology, emergence of antibiotic-resistant strains, and requirement of specialized targeted therapy to tackle the disease.
Case presentation: Here, we present a case of an eight-year-old male patient with an extra-articular abscess around his left-elbow osteomyelitis, which was clinically confused with septic arthritis. The causative organism was methicillin-resistant Staphylococcus aureus (MRSA), which was resistant to most of the antibiotics but sensitive to linezolid. Given that pediatric osteomyelitis has a higher chance of articular extension, prompt treatment is essential to avoid permanent damage to the joint.
Conclusion: In conclusion, considering the rarity of MRSA-induced intra-articular osteomyelitis, a high index of suspicion is needed to diagnose it as soon as possible clinically and radiologically. This disease should be considered as a differential diagnosis in patients with painful joint swelling.