A Young Woman With Painful, Swollen, Indurated Leg Lesions
An 18-year-old young woman presented to the emergency department with numerous painful lesions on her lower extremities of 3 weeks’ duration. She had no recent history of trauma, fever, or any other systemic symptoms. Previous similar episodes had been treated with antibiotics. Her medical history was significant for systemic lupus erythematosus and depression. Her current medications were mycophenolate mofetil, hydroxychloroquine, and prednisone.
On physical examination, the patient was afebrile, with stable vital signs. Examination of the skin revealed numerous poorly defined, tender, erythematous, indurated plaques on both lower extremities, the largest of which was 12 × 7 cm near her right knee. The overlying skin was intact, with no warmth, but with some atrophic changes.
She had full range of motion of all joints. The rest of the examination findings were unremarkable.
What do you suspect is causing these lesions?
(Answer and discussion on next page)
Answer: Lupus Erythematosus Panniculitis
An 18-year-old young woman presented to the emergency department with numerous painful lesions on her lower extremities of 3 weeks’ duration. She had no recent history of trauma, fever, or any other systemic symptoms. Previous similar episodes had been treated with antibiotics. Her medical history was significant for systemic lupus erythematosus (SLE) and depression. Her current medications were mycophenolate mofetil, hydroxychloroquine, and prednisone.
On physical examination, the patient was afebrile, with stable vital signs. Examination of the skin revealed numerous poorly defined, tender, erythematous, indurated plaques on both lower extremities, the largest of which was 12 × 7 cm near her right knee. The overlying skin was intact, with no warmth, but with some atrophic changes.
She had full range of motion of all joints. The rest of the examination findings were unremarkable.
Based on her medical history and clinical presentation, the young woman received a diagnosis of lupus erythematosus panniculitis (LEP).
Laboratory test results showed a white blood cell count of 8,900/µL and a C-reactive protein level of 20.1 mg/L. She was started on dapsone. Over the next 3 days, her pain and erythema improved, and she was discharged on dapsone with a corticosteroid taper.
Discussion
LEP is an uncommon cutaneous manifestation of lupus that is characterized by inflammation of the subcutaneous fat. It can occur in isolation or in association with discoid lupus erythematosus or SLE. The skin lesions can precede the diagnosis of SLE or can occur several years later. Approximately 2% to 5% of patients with SLE develop LEP.1 It usually affects middle-aged women, although a few cases have been reported in adolescents and younger children.2-4
Clinical findings include tender subcutaneous nodules or plaques that most commonly involve the face and proximal extremities. The lesions have a chronic, remitting course and can be exacerbated by trauma. The overlying skin can range from light pink and erythematous to a red-brown dyspigmentation, with scaling, follicular plugging, and telangiectasia. Subcutaneous atrophy and scarring occurs, resulting in sunken areas at the sites of earlier lesions.5
Other conditions presenting with chronic lower extremity nodules include erythema nodosum, subcutaneous sarcoidosis, and cutaneous T-cell lymphoma. The chronic course and rare distal distribution of LEP differentiates it from erythema nodosum. In the absence of a history of lupus, the diagnosis is histopathologic, with test results showing hyaline fat necrosis.
Early intervention is critical in order to avoid complications such as scarring, atrophy, and calcification. Oral hydroxychloroquine is the first-line therapy for LEP. Thalidomide, dapsone, and intravenous immunoglobulin have been used in recalcitrant cases or for patients who are taking antimalarial medications.
A history of existing disease, the chronicity of lesions, and a lack of warmth, fluctuance, and fever associated with lesions are important clues to correctly diagnosing LEP and initiating timely and appropriate therapy.
References
1. Sanavi S, Afshar R. Panniculitis as the first sign of systemic lupus erythematosus. Indian Dermatol Online J. 2011;2(1):45-46.
2. Weingartner JS, Zedek DC, Burkhart CN, Morrell DS. Lupus erythematosus panniculitis in children: report of three cases and review of previously reported cases. Pediatr Dermatol. 2012;29(2):169-176.
3. Guissa VR, Trudes G, Jesus AA, Aikawa NE, Romiti R, Silva CA. Lupus erythematosus panniculitis in children and adolescents. Acta Reumatol Port. 2012;37(1):82-85.
4. Fernandes S, Santos S, Freitas I, Salgado M, Afonso A, Cardoso J. Linear lupus erythematosus profundus as an initial manifestation of systemic lupus erythematosus in a child. Pediatr Dermatol. 2014;31(3):378-380.
5. Patterson JW. Panniculitis. In: Bolognia JL, Jorizzo JL, Schaffer JV, eds. Dermatology. 3rd
Rajan Arora, MD, is a pediatric emergency medicine fellow at the Children’s Hospital of Michigan in Detroit.
Earl Hartwig, MD, and Nirupama Kannikeswaran, MD, are associate professors in the Division of Pediatric Emergency Medicine at Wayne State University and Children’s Hospital of Michigan.