Physical Exam – Bleeding into Skin

Bleeding manifestations in skin and mucous membranes

Note how the following definitions vary significantly according to source!

International Working Group (IWG) definitions:

“The most frequent hemorrhagic manifestation in ITP is purpura. Purpura broadly encompasses any kind of mucocutaneous bleeding; it is commonly referred to as “dry” when bleeding is confined to the skin and “wet” when mucous membranes are also involved. The IWG recommends against the use of these terminologies because they lack precision.”

International Working Group on the standardization of bleeding assessment in immune thrombocytopenia; Blood. 2013;121(14):2596-60

The following are IWG definitions of bleeding in the skin:

Lesion	Site of bleeding	Definition
Petechiae	Epidermis and dermis	Red (recent) or purplish (a few days old) discoloration in the skin with a diameter of 0.5-3 mm that does not blanche with pressure and is not palpable.
Ecchymosis (purpuric macule, bruises, or contusions)	Epidermis and dermis	Flat, rounded, or irregular red, blue, purplish, or yellowish green patch, larger than a petechia. Elevation indicated spreading of an underlying hematoma into the superficial layers of the skin.
Hematoma	Subcutaneous tissue	Bulging localized accumulation of blood, often with discoloration of overlying skin.

The following are IWG definitions of bleeding within visible mucous membranes such as the mouth:

Lesion
Petechiae, purpuric macules, and ecchymosis	Same as for skin.
Bulla, vesicle, and blister	Visible raised, thin-walled, circumscribed lesion containing blood. Each bulla (>5.0 mm) is larger than a vesicle. Bullae, vesicles, and blisters should be counted together as bulla.

Up-To-Date definitions:

• Petechiae:  
  • Small, flat (nonpalpable), red, discrete lesions (typically <2 mm in diameter) that do not blanch under pressure; these often occur in dependent areas of the body (lower legs in ambulatory patients; sacral area in recumbent patients).
  • Elsewhere in Up-To-Date, petechia are defined as small capillary hemorrhages that appear smaller than bruises and characteristically develop in crops in areas of increased venous pressure, such as the dependent parts of the body.
  • Petechiae are the smallest bleeding lesions (pinhead in size), and suggest problems with platelet number or function.
• Purpura:
  • Refers to a lesion caused by coalescence of petechiae.
  • Purpura on the skin is sometimes referred to as “dry purpura.”
  • Purpura due to thrombocytopenia is nonpalpable and often occurs in dependent areas of the body. 
  • Hemorrhagic blisters in mucous membranes, such as the oral mucosa, are sometimes called “wet purpura”; this finding may be a predictor of more severe bleeding.
• Bruise (ecchymosis) – a collection of blood beneath the skin resulting from extravasation of blood from surrounding vessels.

FIRST DERM definitions:

• Petechiae are circumscribed deposits of blood (that is, small purpuric lesions) which are less than 0.5 cm in size (usually 1 to 2 mm).
• Purpura:
  • Term used to describe a reddish discoloration of the skin or mucous membranes due to extravasation of red blood cells from blood vessels into the surrounding tissue.
  • Greater than 0.5 cm in size. 
• Ecchymoses (bruises) are larger, deeper collections of blood under the skin (>1 cm in size).

Lotti T. Int J Dermatol. 1994;33:1-10

• Purpura
  • Discoloration of the skin due to extravasation of red blood cells
  • Pressure by fingers or diascopy fails to blanch the lesion
  • Purpuric lesions may have different aspects and sizes:
    • Petechiae are small lesions up to 2 mm in diameter that often occur in crops.
    • Ecchymoses are larger, sometimes figurate lesions caused by extravasation of red blood cells

See case study.