Introduction The granulomatous diseases discussed in this chapter may be defined as having an inflammatory cutaneous infiltrate in which histiocytes are the preponderant inflammatory cells. While cutaneous sarcoidosis is the prototype of non-infectious (sterile) granulomatous dermatitides, there are a number…
Key features ▪ Cutaneous xanthomas can signal the presence of an underlying hyperlipidemia or monoclonal gammopathy ▪ An understanding of basic lipid metabolism provides insight into the underlying hyperlipoproteinemias as well as the formation of xanthomas ▪ The major forms…
Overview The histiocytoses represent a group of proliferative disorders that share a common CD34 + progenitor cell in the bone marrow. Three “histiocytes” of cutaneous importance are: (1) the Langerhans cell , which migrates to and from the epidermis and…
Child Abuse Synonym ▪ Battered child syndrome Key features ▪ Signs of physical abuse include: unexplained bruises; injuries of the thorax, abdomen, buttocks, genitals, chin, ears, or neck; curvilinear marks; and cigarette burns or other well-demarcated burns ▪ Signs of…
Introduction According to the Diagnostic and Statistical Manual of Mental Disorders (DSM-5), the essential feature of a substance use disorder is a cluster of cognitive, behavioral, and physiologic symptoms whereby an individual continues to use a substance despite significant substance-related…
The skin is our primary interface with the environment. Amongst Earth's creatures, humans are unique in their ability to manipulate the environment by manufacturing clothing, shelter, and heating or cooling devices to allow them to live in a variety of…
All skin can react to light because it contains molecules (chromophores) whose chemical structures are capable of absorbing ultraviolet radiation (UVR) or other electromagnetic energy. This absorbed energy is then either re-emitted harmlessly as biologically inactive radiation or diverted to…
Key features ▪ Exposure of the skin to UV light has acute, short-term effects and chronic, long-term effects, both of which are wavelength-dependent. Profound effects also occur with non-erythemogenic doses of UV light ▪ UV light affects the skin's immune…
Insects Insect Bites and Stings (Class Insecta) Key features ▪ Pruritic papules sometimes progress to vesiculobullae or persistent prurigo nodularis-like lesions ▪ Papular urticaria may be localized to sites of bites or generalized ▪ Pseudolymphomatous reactions occasionally occur ▪ Anaphylaxis…
Scabies Synonyms ▪ Itch mite infestation ▪ “Seven-year itch” Key features ▪ Human scabies is a pruritic condition caused by infestation with the host-specific mite Sarcoptes scabiei var. hominis , which lives its entire life within the epidermis ▪ Although…