Table 1

Differential diagnoses for PPD

DIAGNOSISCLINICAL CHARACTERISTICSCONFIRMATION
Progressive pigmentary dermatosesNonpalpable cayenne pepper–like purpura on an orange-brown macular baseBiopsy only if clinical diagnosis is in question
Stasis dermatitisHyperpigmentation, varicose veins, dependent edema; scaling, crusting, and ulcerations might be presentUnderlying venous insufficiency
Leukocytoclastic vasculitisPainful palpable purpura on lower extremities, which might ulcerateSkin biopsy
Purpuric contact dermatitisPurpuric macules, papules, patches, and nodules following textile distributionAvoidance of suspected contactant
Early mycosis fungoidesInitial erythematous patches affecting lower trunk and buttocks, progressing to infiltrated plaques and tumoursSkin biopsy
  • PPD—pigmented purpuric dermatoses.