Table 6-2 Additional Primary Lesions: Pustules, Furuncles, Nodules, Cysts, Wheals, Burrows

Pustule

Small palpable collection of neutrophils or keratin that appears white

Wheal

area of localized dermal edema that evanesces (comes and goes) within a period of 1-2 days

Furuncle

inflamed hair follicle

nodule

larger and deeper than a papule

urticaria

many variable sized 1-10 cm wheals on lateral neck, shoulders, abdomen, arms, and legs

subcutaneous mass/cyst

mobile or fixed, encapsulated collections of fluid or semisolid

Carbuncle

multiple furuncles together

scabies

multiple small 3-6 mm erythematous papules on abdomen, buttocks, scrotum, and shaft and head of penis with four burrows noted on interdigital web spaces

burrow

small linear or serpiginous pathways in the epidermis

epidermal inclusion cyst

solitary 2 cm tethered subcutaneous cyst with overlying punctum releasing caseous whitish yellow substance with foul odor

keloid

solitary 4 cm pink and brown scar-like nodule on central chest at sight of previous trauma

lipoma

solitary 9cm mobile rubbery subcutaneous mass on left temple

dermatofibroma

solitary blue-brown 1.2 cm firm nodule with positive dimple sign and hyperpigmented rim on left lateral thigh

pilar cyst

three 6-8 mm mobile subcutaneous cyst on vertex scalp, that on excision reveal pearly white balls

furunculosis

two large 2-cm furuncles on forehead, without fluctuance

acne vulgaris

~15-20 pustules and acneiform papules on buccal and parotid cheeks bilaterally

bacterial folliculitis

~30 2-5 mm erythematous papules and pustules on frontal, temporal, and parietal scalp