Macroscopic Skin Lesions

LOs -- (1) Describe skin lesions, explaining and illustrating each of the following: size, type (eg, vesicle, bulla), color, configuration (eg, annular, targetoid, discoid), arrangement (eg, solitary, grouped, linear, reticular), and distribution and location. (2) Explain the importance of physical examination of the skin.

Why to examine skin

Thorough skin exam is done to assess for new or changing skin lesions

• have to know what abnormal skin looks like because a change of skin lesions can cause skin cancer, like melanoma

Skin lesion description

Area of skin that has abnormal growth or appearance compared to surrounding skin

• Primary and secondary lesions

Primary vs Secondary Lesions

• Primary skin lesions are abnormal skin conditions present at birth or acquired over a lifetime.

• Secondary skin lesions are the result of manipulated or irritated primary skin lesions. For example, if a nevus (collection of melanocytes) is scratched until it bleeds and scabs, the scab would be an example of a secondary skin lesion.

Medical language for skin lesions has been standardized to include

size, type, color, configuration, arrangement and distribution

Size for lesions - what to report

Report the width and the height of the lesion, which is measured in mm or cm

• “there is a 7 mm by 14 mm patch”

Usually, a pigmented lesion larger than 6mm in size will raise suspicion for malignancy

Types of lesion - may need to palpate the lesion to see if its depressed, raised or flat

When palpating lesion, looking for swelling or consistency

• Consistency will range from hard to soft depending on composition of the lesion

Bullae are elevated lesions and a fluid filled while papules are firm on palpation, but also elevated

Chart of lesions

Macule	A flat lesion <1 cm in size without elevation or depression
Patch	A flat lesion >1 cm in size without elevation or depression
Papule	An elevated, solid lesion <1 cm in size
Plaque	An elevated, solid lesion >1 cm in size
Vesicles	Circumscribed elevations of the skin containing clear fluid, <1 cm in diameter
Bullae	Circumscribed elevations of the skin containing clear fluid, >1 cm in diameter
Pustules	Papules containing a purulent exudate that may be white, yellow, or greenish-yellow
Erosion	Skin lesion with loss of epidermis
Ulcer	Skin lesion with loss of epidermis and dermis (deeper than erosion)

Macule is smaller than a patch, both raised (macule is less than 1 cm, patch is over 1 cm)

Papule is elevated and solid, but smaller than 1cm while plaque is over 1 cm

Vesicles and bullae are circumscribed elevations of skin with clear fluid, but vesicles are less than 1 cm and bullae are more than 1 cm in diameter

Erosion occurs with loss of epidermis

Ulcers are skin lesions with loss of epidermis and dermis, which is deeper than erosion

Pustules are papules that contain purulent exudate, yellow, white or greenish

Petechiae vs Purpura

Purpura are flat <1cm spots with less than 4mm in diameter

• Can be purple/red spots and patches on skin and mucous membrane, including the lining of the mouth

Petechiae are flat lesions, greater than 1 cm and have a diameter that is from 4-10 mm

Color of skin lesions can vary both lighter and darker than original skin tone

Old scars can sow white and necrotic lesions will be dark purple or black

• A bruise can be yellow, green

• Skin lesions are usually associated with inflammation, so they tend to be erythematous

Patients with dark skin have increased melanin, which can make dark lesions stand out less

Lichen planus is a chronic inflammatory disease that can impact skin, nails or oral mucosa, and has the 6 Ps to describe it

• Pruritic (itchy), purple, polygonal, planar, papules and plaques

• Lichen planus papules can range from pink to violate papules that coalesce to form plaques

Configuration refers to the

shape of an individual lesion, whether is round, square or oval

• is it symmetric or asymmetric?

• other shape descriptions are annular, cerebriform, discoid, polycyclic and targetoid

Annular is circular with central clearing, kind of ring shaped

Cerebriform resemble how the brain looks

Discoid is round and circular, like a disc

Polycyclic has multiple rings

Targetoid looks like a bull’s eye

Shape of lesions do not point to a specific diagnosis, but can narrow the differential

can differential tinea corporis annular lesions from the targetoid lesions in patients with erythema multiforme

also patients with SLE tend to have discoid lesions, including at fingers

Discoid lupus erythematosus is a chronic cutaneous lupus erythematosus, where the cutaneous lesions arise as apart of full blown systemic lupus erythematosus (SLE)

Lesions have small risk of progressing to squamous cell carcinoma, due to chronic inflammation

Arrangement of lesions

Some lesions are solitary, others are in specific arrangements or patterns

• Arrangement of lesions are linear, grouped or reticular

• groups of vesicles are in linear arrangement shown in this picture

Group arrangement is apparent on left picture — herpes labialis

Reticular (net-like) arrangement that occurs in livedo reticularis (blue molting of skin due to poor circulation)

Distribution and location of the lesion

Distribution refers to whether the lesion is singular, in a discrete location or localized to a specific body part or widespread lesion location

Location refers to the anatomical position of where the lesion is on patients body

• Use ventral, dorsal, cranial, caudal, proximal, distal

Lesions follow a dermatomal distribution which is based on a skin map that has various layers supplied by a unique spinal nerve root

Herpes zoster, known as shingles, is a painful vesicular rash in dermatomal distribution secondary to reactivation of varicella zoster virus, which is a dsDNA virus

• Will cause pain, medicate for pain control

Borders

Esp important for lesions that are pigmented

Lesions with regular borders are most likely benign (mole) while the irregular borders are more likely malignant, as in melanoma

Skin lesion for melanoma, use ABCDE guide

Asymmetry

Border

Color

Diameter

Evolution

A 3-year-old boy is brought to the pediatrician by his mother who reports that he has a mark on his forearm that she first observed shortly after birth. On examination, you note a flat lesion that is 3.0 cm in diameter. Which of the following is the best term to describe this lesion?

Macule

Papule

Patch

Plaque

Vesicle

Patch because its a flat lesion over 1cm in size, unlike the macule that is less than 1 cm

Melanoma has the worst prognosis of all skin cancers, and sun exposure is one of the major risk factors. One way to recognize concerning lesions is by noting the ABCDE of melanoma. What does the B stand for?

Basaloid

Big

Border

Brown

Bumpy

Border

A 47-year-old woman presents to the dermatologist with a lesion of the left nasal ala that has been present for 3 months. On palpation, the lesion feels raised. You measure the diameter to be 0.5 cm. Which of the following is the best term to describe this lesion?

Erosion

Macule

Papule

Patch

Bulla

Papule, because that’s an elevated solid lesion less than 1 cm in size