Infection of skin and subcutaneous tissue by atypical mycobacteria, that is, mycobacteria other than those responsible for tuberculosis and leprosy, expressed clinically as keratotic and crusted papules, plaques, nodules, and tumors that may be punctuated by draining sinuses and by ulcers.
A malignant neoplasm made up of abnormal germinative cells analogous to those that compose the folliculosebaceous-apocrine germ in an embryo and that usually manifests clinically as a papule or nodule which may become ulcerated.
Cutaneous and subcutaneous lesions, usually nodules, that have become keratotic, crusted, and ulcerated as a consequence of infection by a variety of deep fungi, i.e., fungi situated in the dermis and subcutis, some of which may be disseminated to other organs.
Infundibulitis, usually a suppurative inflammatory process that involves infundibula, is either noninfectious, as in the case of pustules of acne vulgaris, or infectious, as in the case of pustules caused by Staphylococcus aureus.
Keratotic spikes that emerge from dilated ostia of infundibula and are equidistant from one another.
A benign neoplasm of keratinocytes that consists of pigmented macules, papules, and plaques distributed on sun-exposed sites for a solar lentigo and the reticulated type of seborrheic keratosis, which represents a later stage of solar lentigo, and on the trunk mostly for other types of seborrheic keratosis unrelated to solar lentigo.