Morphology and Common Derm Diagnoses

Macule

flat lesion, less than 1cm

Patch

flat lesion greater than 1cm, generally scaly

Papule

raised lesion, less than 1cm

Plaque

solid elevated lesion greater than 1cm

Nodule

solid, raised lesion, less than 1cm that extends deeper to the dermis and/or subcutaneous tissue

Cyst

spherical fluid filled lesion

Wheal

swelling of the skin, hive like, urticarial papule or plaque

Vesicle

fluid filled pouch or lesion, generally less than0.5cm but up to 1cm

Bulla

(singular) large blister greater than 1cm

Bullae

(plural) large blisters greater than 1cm

Pustule

pus filled, thin walled pocket on the epidermis of the skin

Erosion

loss or broken down area of the epidermis

Ulcer

loss or broken down area of the epidermis and the upper portion of the dermis

Atrophy

loss of normal thickening of the skin, change of skin quality, easy to bruise

Scaling

abnormal shedding or accumulation from the upper layer of skin

Crusting

hardening, purulent deposits from dried fluid

Excoriations

injury to the surface of the skin resulting from scratching

Fissures

separation of the skin from excessive tension or decreased elasticity; cracking of the skin

Lichenification

thickening of the skin, leather-like

Violaceous

violet or reddish with a bluish-purple presentation

Erythematous

red or reddish presentation

Purpuric

bruised or bruised like patch

Actinic keratosis (AK)

precancerous spots from the sun, a small percentage can develop into skin cancer

Alopecia

hair loss (areata, totalis, universalis, androgenetic, telogen effluvium)

Arthropod hypersensitivity reaction

insect bite reaction

Atypical/Dysplastic nevus

disordered cells (mild, moderate, severe)

Basal cell carcinoma

most common skin cancer, grows locally and can become invasive if untreated

Benign nevi

benign moles

Blue nevus

blue to gray colored mole

Cafe au lait

“coffee with milk” birthmark

Cherry angiomas

collection of small blood vessels, benign

Condyloma acuminatum

genital wart caused by HPV

Compound nevus

raised mole with pigmentation

Dermatofibroma (DF)

benign dermal nodule, usually scar-related “scar tissue bump”

Eczematous dermatitis (eczema)

dry, itchy rash

Epidermal inclusion cyst

slow-growing benign cyst from trapped keratin under the skin

Excoriations

scratch marks

Fibrous papule

firm bump usually on the nose

Flat seborrheic keratosis

“sun spots” that are flush with skin, usually genetic

Folliculitis

inflammation of the hair follicle

Hidradenitis suppurativa

chronic painful nodules and cysts, usually groin or axilla

Hirsutism

unwanted hair

Hyperhidrosis

excessive sweating

Inflamed verruca vulgaris

irritated wart

Intradermal nevus

flesh-colored raised mole

Irritated seborrheic keratosis (ISK)

irritated age spot, can be treated with liquid nitrogen

Junctional melanocytic nevus

flat mole

Keloid

raised scar that grows beyond wound borders

Lentigenes

freckles

Melanoma

most dangerous skin cancer, can spread internally

Milium

tiny white cyst-like bump

Molluscum contagiosum

viral skin-colored to pink papules

Non melanoma skin cancer (NMSC)

includes BCC and SCC

Onychomycosis

nail fungus

Photoaging

premature skin aging from sun exposure

Pilar cyst

commonly on scalp

Post inflammatory hyperpigmentation

temporary darkening after skin injury

Post inflammatory hypopigmentation

temporary lightening after skin injury

Prurigo nodule

itchy hard nodules from chronic scratching

Psoriasis

rapid skin cell turnover causing plaques

Pyogenic granuloma

vascular growth that bleeds easily

Scabies

mite infestation causing rash

Seborrheic keratosis

benign “age spots,” genetic, not sun-related

Squamous cell carcinoma (SCC)

second most common skin cancer, can spread

Stasis dermatitis

rash from poor circulation and leg edema

Telangiectasia

small dilated blood vessels

Tinea

superficial fungal infection (pedis, capitis, manuum, cruris, faciei, corporis)

Tinea versicolor

yeast overgrowth causing skin discoloration