cutaneous

Cutaneous refers to the skin or structures related to the skin. The term comes from the Latin cutis, meaning skin. In medical language, cutaneous describes tissues, conditions, and manifestations that involve the integumentary system, as distinct from subcutaneous tissues or deeper organs. It is used in phrases such as cutaneous nerves and cutaneous manifestations of disease.

Anatomy: The skin is the body's largest organ, consisting of three layers: the epidermis, dermis, and hypodermis (subcutaneous tissue). The epidermis contains keratinocytes, melanocytes, Langerhans cells, and Merkel cells. The dermis houses connective tissue, blood vessels, nerves, hair follicles, and glands. The hypodermis is primarily adipose tissue. Along with cutaneous appendages and receptors, these layers enable protection, sensation, and secretory functions.

Functions: The cutaneous system forms a protective barrier, minimizes water loss, regulates temperature, and participates in immune defense. It provides sensation through cutaneous nerves and contributes to vitamin D synthesis and various metabolic processes.

Clinical relevance: Cutaneous conditions include infections, inflammatory diseases such as dermatitis and psoriasis, acne, and neoplasms such as melanoma and non-melanoma skin cancers. Skin signs can reflect systemic disease. Evaluation typically involves physical examination, dermoscopy, biopsy, and histopathology; treatment ranges from topical therapies to systemic medications and procedures depending on the condition.