Dr. Kahn presented a series of case studies, illustrating some key differentiating features that can help make the diagnosis:
• Case 1: A 2.5-year-old girl is carried into the emergency department (ED) after limping for 2 days. She began limping after coming home from the playground. She has no fever, rash, or constitutional features, and appears happy and smiling. Her hips, knees, ankles, and feet are not swollen, warm, or tender. There is tenderness at a point along her right tibia. The diagnosis is toddler’s fracture.
• Case 2: A 2.5-year-old girl is carried into the ED after limping for 2 days. There is no history of trauma, but the pain has become so severe that it awakens her at night. She refuses to walk, has constant pain not controlled by NSAIDS, and is cranky, febrile, tachycardic, and appears sick. She holds her right hip in a FABER (flexion, abduction, and external rotation) position. Her labs are C-reactive protein of 100 mg/L and a white blood cell of 30,000. The diagnosis is septic arthritis, with immediate referral to an orthopedist.
• Case 3: A 2.5-year-old girl walks into the ED after limping for 3 months. She denies having any pain, and her mother says she is lazy. She no longer alternates her feet when ascending steps and has fallen once when descending the stairs. When you examine her, she shows edematous and purple eyelids and a rash over her knuckles, as well as proximal weakness. Her muscle enzymes are elevated. The diagnosis is juvenile dermatomyositis.
• Case 4: A 2.5-year-old girl walks into the ED after limping for 3 months. An active girl, she fell off a slide the previous day and developed a large effusion after scraping her knee. She is smiling and running around the ED. She has no fever, malaise, joint swelling, or nocturnal wakening, although her mother says her limp is worse in the morning but lessens after breakfast. Inflammatory markers are normal and rheumatoid factor is absent. The diagnosis is oligoarticular juvenile idiopathic arthritis.
• Case 5: A 2.5-year-old girl walks into the ED after complaining that her legs have bothered her for 3 months. At night, she complains of lower leg pain in both legs and awakes sometimes at night from the pain but seems fine in the morning. No erythema or swollen joints are seen. She has been taken three times to the ED over the last few weeks, but blood tests and x-rays are said to be normal. Fever, rash, or constitutional symptoms are absent. The diagnosis is growing pains.
Dr. Kahn reported having no relevant financial disclosures.