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