Subacute cutaneous lupus erythematosus Flashcards
What are the skin types most commonly affected by DLE? SCLE?
- african americans for DLE
- whites for SCLE
What percent of patients w/ SCLE will eventually meet SLE criteria?
30-50%
What causes SCLE?
genetic factors: HLA-B8 (strongest association) and HLA-DR3
environmental factors: Immune tolerance is lost or autoimmunity develops through exposure to environmental triggers such as exposure to ultraviolet radiation(UVR) or photosensitising drugs.
- thought that UVR increases Ro and La antigens, which the body forms ANA’s against
What are the genetic associations for SCLE?
HLA- B8 (strongest) and HLA- DR3
- complement deficiencies
What antibodies do you see with SCLE?
Anti-Ro/SS-A (75%-90%)
What complement deficiencies is SCLE a/w?
early intrinsic pathway (C1, C2, C4)
(think, subacute is sorttt of early, so early intrinsic pathway is deficient)
What are the two clinical variants of SCLE?
- papulosquamous SCLE: psoriasiform plaques
- Annular SCLE: scaly polycyclic annular plaques with central clearing
What are typical locations of SCLE?
- sun exposed areas
lateral face (central face spared)
V-chest, upper back
How do lesions of SCLE heal?
with hypopigmentation, but no scarring
Most common systemic finding a/w SCLE, what should you ask your patient?
joint pains in 70% , make sure to ask about this
Annular SCLE:
psoriasiform SCLE
Histopathology of SCLE:
- compact hyperkeratosis
- prominent epidermal atrophy
- vacuolar interface dermatitis
- pigment incontinence
- mucin deposition
First line tx for SCLE?
sun protection and antimalarials
What should you always think about as possible inciting factors for patient with SCLE?
drugs and Early intrinsic complement deficiency!
