Lupus panniculitis in Adult
Lupus panniculitis is sometimes termed lupus profundus and can be associated with overlying discoid lupus erythematosus (DLE) in approximately one-third of patients. Lupus panniculitis is thought to be caused by an autoimmune reaction in the deep dermis and adipose tissue. The first stage of lupus panniculitis is active inflammation with painful nodules, followed by the second stage of subcutaneous atrophy that can be cosmetically disfiguring.
Lupus panniculitis, like systemic lupus erythematosus (SLE), occurs more commonly in women. Lupus panniculitis develops in approximately 5% of patients with SLE but can occur as an isolated disease. Cutaneous manifestations of lupus panniculitis can develop years before or after the diagnosis of SLE. The average age of onset is 30-40s.
Male sex, lower extremity involvement, and concomitant DLE are associated with SLE.
L93.2 – Other local lupus erythematosus
239888002 – Lupus panniculitis
Differential Diagnosis & Pitfalls
- Morphea – Usually presents with purplish borders, fewer nodules, and less facial involvement.
- Sarcoidosis – Less induration, more epithelial changes.
- Subcutaneous panniculitis-like T-cell lymphoma (SPTCL) – Can present similarly both clinically and histologically to lupus panniculitis. Clinical features favoring SPTCL include the presence of systemic symptoms, leukopenia, and a high erythrocyte sedimentation rate. On histopathology, the presence of a polyclonal T-cell infiltrate, mixed CD4/CD8 population, and negative T-cell gene rearrangement studies all favor the diagnosis of lupus panniculitis over SPTCL. Lupus panniculitis lesions contain a higher percentage of CD123-positive plasmacytoid dendritic cells compared to SPTCL.
- Other types of panniculitides – Requires pathologic tissue examination to differentiate.
- Tumid lupus erythematosus – Photosensitive distribution of erythematous papules, nodules, and plaques.
- Lipoatrophy – Associated with history of injected medications or of highly active antiretroviral therapy treatment for HIV.