Integumentary System
Ch 5 Anatomy & Practical Applications by Dr. Peterson
Skin Structure & Function
There are 2 layers of the skin:
- Epidermis
- Dermis
- [The subcutaneous or hypodermis layer consists of areolar (which serves as a cushion for organs & blood vessels) & adipose (fat) tissue.
The epidermis consists of 4 types of cells:
- Keratinocytes
- Melanocytes
- Langerhans cells
- Tactile cells
Actinic Keratosis
Actinic keratosis (AK) is a condition of thickened scaly growth (keratosis, or overproduction of keratinocytes) caused by sunlight (actinic). Actinic keratoses are ultraviolet (UV) light-induced lesions of the skin which may progress to invasive squamous cell carcinoma.
Melanoma
Melanoma is the most dangerous type of cancer (CA). This condition is the leading cause of skin-related death. The most common (m/c) location in women is on the legs and in men, the back. Some of the characteristics of these cancerous nevi (moles) are irregular borders, growth > 6 mm, atypical black/brown color, and that they change over time.
Langerhans Cell Histiocytosis
Found m/c in children, it's presentation consists of rash, chronic ear infections, unexplained swelling of the head and pulmonary (lung) complications. Langerhans cells are found in numerous areas, including the skin, pituitary gland and lung.