Episode 187: Septic Joint in Children

We discuss the diagnosis and management of septic arthritis in the pediatric population. Hosts: Brian Gilberti, MD Ellen Duncan, MD https://media.blubrry.com/coreem/content.blubrry.com/coreem/Septic_Joint_in_Children.mp3 Download 2 Comments Tags: Infectious Diseases, Pediatrics Show Notes General Pain in joint for pediatric patient has a broad differential, including transient synovitis and septic arthritis Transient synovitis, also known as toxic synovitis, is a common condition affecting kids aged 3-10 and often occurs after a viral infection. It is typically self-limiting and not considered a serious condition. Septic arthritis is an infection in the joint space, typically affecting only one joint. It is often difficult to diagnose due to the fact that many patients, particularly under the age of 3, may not be able to localize their pain to a specific joint. Workup Diagnostic work-up for septic arthritis begins with blood work, which includes a complete blood count (CBC), erythrocyte sedimentation rate (ESR), C-reactive protein (CRP), and blood cultures. Lyme disease studies may also be necessary since Lyme disease can cause joint pain. Patients with transient synovitis typically have mild elevation in inflammatory markers, while those with septic arthritis usually show a significant elevation. Imaging studies, including X-rays, ultrasound to evaluate for a joint effusion, and MRI to assess for associated osteomyelitis, are also part of the diagnostic approach. The Kocher criteria, developed specifically for septic arthritis of the hip, are a useful tool for clinical decision-making. The criteria include fever above 38.5 C, inability to bear weight, ESR above 40, and a white blood cell count above 12,000. 1 criterion met = 3% probability of septic arthritis 2 criteria met = 40% probability of septic arthritis 3 criteria met = 93% probability of septic arthritis 4 criteria met = 99+% probability of septic arthritis   If septic arthritis is suspected, orthopedics should be consulted immediately. Joint fluid aspiration is necessary for diagnosis and should not be delayed. The fluid should be sent for cell count, gram stain, glucose, culture, and PCR if available. Septic arthritis is most commonly caused by bacterial infections, with Staph aureus being the most common organism. In school-age children, other bacteria such as Strep pyogenes, Strep pneumoniae, and Haemophilus influenzae should also be considered. In preschool-aged children, K. kingae is also considered. In older children and neonates, the range of potential bacteria varies. Management