A CASE OF STERNOCLAVICULAR JOINT SEPTIC ARTHRITIS. E.H. Elbadawy 1 , K. Gopal 1 ; 1 Fairview Hospital, Cleveland, OH (Tracking ID #76754) LEARNING OBJECTIVES: 1-To recognize the clinical picture of sternoclavicular septic arthritis. 2-To emphasize the importance of early diagnosis and treatment in preventing devastating complications. CASE INFORMATION: A 43-year old white male admitted with 2 days history of worsening dull aching pain, swelling and erythema at the right sternoclavicular joint (SCJ) area. Condition started 2 days after he sustained a fall as he was wrestling with his 8-year old son. Patient denied fever, chills or dyspnea. Past medical history was significant for hypothyroidism and depression. Patient denied IV drug abuse, alcohol intake or smoking. On examination he was febrile at 103 F with pulse of 125 and blood pressure of 146/81. He appeared to be in pain with significant soft tissue swelling, erythema and marked tenderness over the right SCJ. Range of motion of the right shoulder was severely limited due to pain. Initial laboratory evaluation revealed WBCs of 12.5 k/AL and ESR of 56. Therapy was initiated with imipenem 500 mg IV every 6 hours for possible SCJ septic arthritis because of history of penicillin allergy. SCJ aspiration was unsuccessful in obtaining any fluid. Computed tomography scan revealed soft tissue swelling around the right SCJ with no evidence of fluid collection. Three-phase bone scan showed increased soft tissue activity and delayed bony uptake involving the right SCJ area. Blood cultures drawn on admission grew methicillin-sensitive Staphylococcus aureus and therapy was switched to cefazolin 2 grams IV every 8 hours. Patient reported significant improvement is his symptoms after 3 days of intravenous antibiotics and was discharged home on cefazolin 2 gm IV for total of 4 weeks. Follow-up one week later revealed complete resolution of the soft tissue swelling, tenderness and erythema with painless full range of motion of his right shoulder. IMPLICATIONS/DISCUSSION: Sternoclavicular septic arthritis accounts for 1±9% of septic arthritis cases. Predisposing factors include IV drug abuse, DM, central venous catheters and trauma. Aspiration of the joint can be helpful in confirming the diagnosis and guiding treatment. Unfortunately, the failure rate with this method is high due to the technical difficulty in aspirating the small joint space, as in our patient. Clinical diagnosis requires a high index of suspicion in any patient presenting with swelling and pain around the SCJ. Spread of infection can lead to superior vena cava obstruction, mediastinitis and septic shock. Early diagnosis is critical in order to prevent life threatening complications.