The Skin Flashcards
Seconday lesion
evolves from pirmary skin lesion, (i.e crust of chicken pox) or can be because of scratching or infection
distribution
refers to where on the body the lesions are found (e.g., hands, face, trunk, flexor or extensor surfaces).
3 layers of skin
- epidermis
- dermis
- subcutaneous
vellus hair
short, fine, inconspicuous and usually unpigmented (peach fuzz).
terminal hair
Terminal hair – coarser, thicker and pigmented. Example: - scalp, eyebrows, pubic region.
Three phases of hair
Catagen phase – transitional phase – 3%
Telogen phase – resting phase – 10-15%
Anagen phase – Growing phase – 85-90%
clubbing of nails
rounding of the nail, soft and spongy
Etiologies: Congenital ****Chronic hypoxia*** (i.e. ventricular, septal defect, severe COPD) Heart disease Lung cancer Hepatic cirrhosis
_ people are also ashen appearing and cyanotic
Psoriasis
- small pits in the nails, may be due to cirrohsis
Mee’s lines
discolored lines, due to traumatic event such as illness or metabolic event
Beau’s lines
interruption of growth of nail, appears as an indent
- may follow surgery or metabolic illness
what causes color in skin? brown, yellow, red, blue?
brown: melanin
yellow: carotene, bilirubin (jaundice)
red: carboxyhemoglobin (CO poisoning), polycythemia (increased RBC counts)
bluish-red: de-oxyhemoglobin (cyanosis)
melanocytes
cells containing melanin in organelles called melanosomes. The cells migrate outward to the epidermis.
- albinos: melanin is absent
mobility and turgor
not ease with which skin lifts up - mobility
- note speed which which it returns to place (turgor)
important flexor surfaces?
back of knees, back of neck, back of elbows
- atopic dermatitis is seen here
extensory surface
extensors of elbow and knee
- cirrihosis
- syphillis (palms of hands)
macule
small flat spot, less than 1.0 cm
- benign, loss of melanocytes, not much for treatments
i. e Vitiligo
patch
flat spot or lesion greater than 1.0 cm
i.e. cafe-au-lait spots, looks like little stains of coffee (associated with tumerosclerosis)
papule
raised lesion up to 1.0 cm, reddened
i.e. psoriasis
plaque
raised lesion greater than 1.0 cm
i.e. psoriasis
nodule
firm, hard lesion, deeper than a papule, less than 1/2 cm
cyst
nodule filled with material, liquid or semi-solid - often encapsulated
i.e. inclusion cyst on face, caused by blocked sebaceous gland
vesicles
fluid filled lesions, less than 1.0 cm
- single or in clusters
i.e. herpes zoster virus, found in dermatome skin patches
bulla
fluid filled lesion greater than 1.0 cm
i.e. insect bite
wheal
superficial localized area of skin, blanche with pressure
* these are vascular lesions*
i.e. urticaria