| • | acute form of "pityriasis lichenoides" (see below) |
| • | AKA Mucha-Haberman disease, PLEVA |
| • | recurrent crops of variably purpuric papules that develop crusts, ulcers, vesicles or pustules |
| • | before spontaneously regressing over few weeks |
| • | acute lesions à may result in smallpox-like (varioliform) scars |
PLEVA ddx:
| • | in children: Gianotti-Crosti syndrome, varicella |
| • | lymphomatoid papulosis: a countable number of grouped papular or self-healing nodular lesions |
| • | PLC: the chronic form of "pityriasis lichenoides" |
"Pityriasis Lichenoides"
| • | reccurrent crops of spontaneously regressing papules |
| • | therefore polymorphous, lesions of different age |
| • | all age groups, but more common in first few decades |
| • | T-cell gene rearrangement demonstrate clonal populations of T-cells in select cases |
| • | but shows no significantly documented association with malignant lymphoma |
| • | PLC may regress in months or persist for years (PLEVA usually has a shorter duration) |
| • | spectrum of disease with a variable clinical presentation ranging from mostly acute lesions to mainly chronic lesions |
treatment:
| • | phototherapy provides the best therapeutic response |
| • | high dose tetracycline *not in children < 8years old, nor in pregnant women (2g/day) or erythromycin X 2 months |
histology:
| • | (CD8 lymphocytes predominate in PLEVA; CD4 in PLC) |
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