Septic Arthritis of the Elbow in a Premature Neonate: An Uncommon Disease in an Uncommon Location.

Septic arthritis (SA) is an infrequent diagnosis in the neonate. This case illustrates the presentation of SA within the elbow, an atypical location for neonatal SA. SA should be considered in any neonate with joint swelling, as symptoms are often subtle. Constitutional symptoms of infection, including fever, may not be present in the neonate. Staphylococcus aureus is the most common etiologic organism, and neonatal SA is often caused by hematogenous spread partially due to unique neonatal intraosseous anatomy. Joint aspiration can provide a definitive diagnosis and aid in targeted antimicrobial therapy. Other laboratory tests, including C-reactive protein and erythrocyte sedimentation rate, can aid in diagnosis. Ultrasound and magnetic resonance imaging can demonstrate joint effusion along with osteomyelitis, which is often seen concurrently with neonatal SA. There are no definitive guidelines for the treatment of neonatal SA. Conservative therapy with antimicrobials along with surgical intervention are the mainstays of treatment. Prompt diagnosis and treatment are crucial to decrease permanent joint damage. [Pediatr Ann. 2023;52(8):e292-e296.].