autoimmune connective tissues disease
lupus
-cutaneous lupus:
chronic cutaneous LE, 5-10% develop SLE, discoid lupus most common
discord lupus (type of chronic cutaneous lupus): occurs more in females and African descent. presents with pink plaques with scalene and follicular plugging, and central hypo pigmentation atrophy and scaring. typically present on scalp, ears, face, especially in the concha bowl in ear. usually lesions limited to head and neck if blow the neck more likely to develop systemic lupus. on histology [inflammatory infiltrates surrounding structures, increased mucin deposition] on high power[ hyperkeratosis, follicular plugging, thickened basement membrane zone, vacuolar interface changes]
acute cutaneous LE ( 100% develop SLE) malar rash and diffuse photosensitivity. mild erythema to edematous papule and plaques spares the melolabial folds. generalized erythema (photosensitive eruption with similar lesion morthphlgy classically spares skin overlying joints of hand)
systemic lupus erythematosus -cutaneous lupus lesions, arthritis