Introduction To Dermatology Flashcards
What activity happens in Stratum Basale?
Cells divide by mitosis and some of the newly formed cells become the cells of the more superficial strata
What happens in Stratum Spinosum?
Keratin fibres and lamellar bodies accumulate
What happens in Stratum Granulosum?
Keratohyalin and a hard protein envelope form. Lamellar bodies release lipids. Cells die
What do dead cells do in Stratum Lucidum?
The dead cells lie within dispersed keratohyalin
What happens in Stratum Corneum?
Dead cells with a hard protein envelope; the cells contain keratin and are surrounded by lipids
What are the 3 stages of hair cycle?
Anagen
Active growing phase, 80-90% of hair
Cartagen
2-3 week pages, growth stops/ follicle shrinks, 1-3% of hair
Telogen
Resting phase for 1-4 months, up to 10% of hair in a normal scalp
State the functions of the skin?
Thermoregulation
- insulation, heat transfer
Skin immune system
- it is the first line of defence, innate and adaptive function
Barrier
-protects against mechanical, chemical, microorganisms, ultraviolet light
-keeps in water and electrolytes, macromolecules
Sensation
-temperature, touch, pain
Vitamin D synthesis
-UV light converts 7-dehydrocholesterol to cholecalcifoerol
Interpersonal Communication
-physical appearance, smell, self-identity
What are the causes of skin disease?
Can be external or internal
External
- Temperature, UV, chemical (allergen or irritant), infection, trauma
Internal
-systemic disease, genetics, drugs, infection
Give examples of external causes of skin disease
-Photosensitivity. Commonly caused by medications. Exposed sites are affected. Can be sensitive to UVA, UVB, visible light or a combination of these
-Cold injury such as frostbite, chilblains, skin necrosis, cold urticaria
-trauma, dermatitis Artefacta (where the patients harm themselves)
Give examples of internal causes of skin diseases
- Genetic
- due to Drug reaction
-Autoimmune, Bullous PemPhigoid
Define morphology
The appearance of skin lesions
What are the 10 words that describe skin lesions?
Small usually means less than 5mm
Macule = Small folate circumscribed area
Patch = Larger flat circumscribed area
Papule = Small raised area
Plaque = Larger Raised area
Vesicle = Small fluid filled
Bulla = large fluid filled
Pustule = small pjs filled
Abscess = large pus filled
Erosion = Loss of Epidermis
Ulcer = Loss of epidermis and dermis
What is Acanthosis Nigricans?
Associated with insulin resistance, obesity, malignancy. Flexural distribution. Hyperkeratosis and Hyperpigmentation papules. “Velvety” appearance
What dermatology investigations would you do if you suspect bacterial infection?
Charcoal swab
Ask for MC&S
-Microscopy
-culture
-sensitivities
What dermatology investigations would you do if you suspect viral infection?
- You have to take a viral swab for PCR
- you can swab vesicle/ bulla if vesicular eruption
- if systemic illness, can take throat swab
