Purpura
Pronunciation: PUR-pyoo-ruh
Non-blanching haemorrhagic discolouration of the skin caused by extravasation of red blood cells into the dermis, classified by size as petechiae (<2 mm), purpura (2–10 mm), or ecchymoses (>10 mm).
Full Definition
Purpura describes a range of non-blanching skin lesions resulting from haemorrhage into the dermis or subcutaneous tissue, distinguishable from erythema or rashes by their failure to blanch under pressure (the diascopy test). The term encompasses petechiae (pinpoint lesions), purpura (intermediate), and ecchymoses (bruises). It may be palpable (raised, indicating vasculitis) or non-palpable (flat). In editorial review, editors must ensure the correct size-based terminology is applied and that 'purpura' is not used interchangeably with 'petechiae' or 'ecchymoses.' The word is both a singular and plural noun in clinical use.
Usage
Usage note: Purpura functions as both singular and plural. Do not use it interchangeably with 'petechiae' (which are smaller) or 'ecchymoses' (which are larger). Confirm blanching status is documented when the term appears in examination findings.
In Context
- "Palpable purpura over the lower limbs prompted urgent investigation for leucocytoclastic vasculitis." — Dermatology inpatient note
- "The copy-editor flagged that 'petechiae' and 'purpura' had been used interchangeably in the case series and requested clarification from the author." — Manuscript review