Progressive Rash In A High School Basketball Athlete

Abstract

HISTORY: A 16 year old female high school basketball player presented to the athletic training room with a rash on the bilateral lower extremities. It was first noticed 1 week prior to presentation and had progressed from the feet and ankles proximally to the upper thighs. She stated that she initially had right ankle pain but at presentation felt her left knee was particularly swollen and painful. She denied any significant itching related to the rash but felt her legs were swollen and heavy. She denied any specific joint trauma and had been participating in her usual physical activities. She endorsed that she was currently recovering from an upper respiratory viral illness that occurred prior to the appearance of the rash. She had tried taking oral diphenhydramine for the rash which did not help. PHYSICAL EXAMINATION: She was in no acute distress. Nasal congestion and cough were noted. The legs were diffusely swollen from the ankles to the proximal third of the thighs bilaterally with scattered, non-blanching and non-tender purpuric lesions. There was non-specific tenderness to palpation about the left knee without warmth. It was difficult to assess for a knee effusion as there was significant soft tissue swelling. Knee flexion range of motion was 0 to 150 degrees, pain-free and flexion and extension strength was 5/5. Ligamentous structures of the knees were intact. Sensation to light touch of the bilateral lower extremities was intact. She reported pain in the left knee with gait but was not observed as having a limp. Balance was intact. DIFFERENTIAL DIAGNOSIS: 1)Septic arthritis 2)Transient synovitis 3)Lyme disease 4)IgA Vasculitis (formerly known as Henoch-Schnolein Purpura) 5)Coagulopathy 6)Dermatologic hypersensitivity TESTS AND RESULTS: The patient was sent to the emergency department for further evaluation. Blood pressure was 116/69, pulse was 90, respiration rate was 19 breaths per minute with 100% oxygen saturation, and temperature was 97.5oF. A complete blood count showed normal platelets and no leukocytosis, while a basic metabolic panel showed normal renal function. A urinalysis showed trace blood and left lower extremity vascular ultrasound was negative for DVT. Musculoskeletal ultrasound did not show any intra-articular effusion in the left knee. FINAL/WORKING DIAGNOSIS: IgA Vasculitis (formerly known as Henoch-Schnolein Purpura) with polyarticular involvement. TREATMENT AND OUTCOMES: Our patient was managed conservatively with symptom management as needed. Although there was concern for septic arthropathy, she remained afebrile with no clinical signs of sepsis. The rash and arthralgias resolved within 4 weeks.