Skin Flashcards
1
Q
Functions of the Skin
A
- Protection
- Regulation
- Sensation
2
Q
Protection
A
Barrier between the external environment • Mechanical impacts and pressure • Variations in temperature • Micro-organisms • Radiation (UV light) • Chemicals
3
Q
Regulation
A
• Body temperature is regulated via: =>Sweat glands =>Hair =>Subcutaneous fat • Changes in peripheral circulation • Fluid balance via sweat • Vitamin D synthesis
4
Q
Sensation
A
• Receptors for: => Pressure => Touch => Temperature => Pain
5
Q
Structure of the Skin - 3 layers
A
- Epidermis
- Dermis
- Subcutaneous layer
6
Q
Epidermis
A
• Outer protective layer
• Keratinocytes
=> synthesise the protein keratin
• Cells replaced ~ every 35 days
7
Q
Dermis
A
- Collagen for strength
- Elastic fibers to allow stretch
- Blood and nerve supply
- Hair follicle
- Sebaceous and sweat glands
8
Q
Subcutaneous layer
A
- Hypodermis
* Layer of adipose tissue
9
Q
Types of cells in the Epidermis
A
• Keratinocytes – produce Keratin
• Melanocytes – produce melanin pigment
• Langerhans cells – from the bone marrow
=> provide immunity
• Merkel cells – form the touch receptor with the
sensory neuron
10
Q
Layers of the Epidermis
A
- Stratum corneum
- Stratum lucidum
- Stratum granulosum
- Stratum spinosum
- Stratum basale
11
Q
Layers of the Epidermis
1. Stratum Corneum
A
- Horny layer
- 10-30 layers of dead keratinocytes
- Create a barrier to protect
12
Q
Layers of the Epidermis
2. Stratum Lucidum
A
- Thin translucent layer
* Clear, flat, dead keratinocytes
13
Q
Layers of the Epidermis
3. Stratum Granulosum
A
• 3-5 layers of flattened cells with deteriorating organelles • Lamellar granules => release lipids • Keratohyaline granules => help make keratin
14
Q
Layers of the epidermis
4. Stratum spinosum
A
• Layers of keratinocytes unified by desmosomes
15
Q
Layers of the epidermis
5. Stratum basale
A
- Deepest layer of epidermis
- 1 row of actively mitotic stem cells
- As cells divide & differentiate they move to the surface
16
Q
Structure of the Epidermis
Barrier functions
A
• Keratinocytes => produce keratin = mechanical strength
• Langerhans cells => immune protection
• Lipids and enzymes = chemical protection
• Acid pH 4-4.5
• Skin flora - microorganisms on skin surface
=> repel other microorganisms
17
Q
Dermis layers
A
- Papillary layer => loose connective tissue
* Reticular layer => dense & irregular connective tissue
18
Q
Dermis types of tissue
A
- Collagen => strength
- Elastin => elasticity
- Reticular fibers => protein fibers
19
Q
Dermis glands
A
- Sweat glands => produce sweat = temperature regulation
* Sebaceous glands => produce sebum = lubricates skin
20
Q
Dermis hair follicles
A
• => Protection and temperature regulation
21
Q
The Dermis consists of blood vessels for
A
• Excretion + temperature control
=> Hot = sweating, vasodilation, insensible perspiration
22
Q
Skin Pathologies
A
• Physical disruption of the skin => cuts, grazes, burns, wounds, pressure sores
• Infection
=> Bacterial – cellulitis, impetigo, boils
=> Fungal – athlete’s foot, ringworm
=> Viral – chickenpox, shingles
• Infestation – head lice, scabies
• Systemic pathology – measles, tumours, neuropathy
• Allergies – eczema
• Auto-immune disease – systemic lupus erythematous
• Adverse Drug Reactions – Stevens-Johnson syndrome
23
Q
History Taking in Skin Conditions
A
- Examine the affected area if appropriate
- WWHAM (Who, What, How, • Action taken, Medical history)
- When/where did it start?
- Any other symptoms?
- Any potential triggers?
- Is anyone else affected?
- Occupational history
- General medical history
- Ask the patient what they think it might be
24
Q
Differential Diagnosis
A
- Appearance => red all over/ defined regions?
- Distribution => is it all over the body, in certain places, or random distribution.
- What does it feel like => rough, smooth, lumpy
- Symmetry => diagnostic of some conditions
- Broken skin
25
Red Flags => Referral
* A changing mole
* Widespread lesions
* Recurrent infections
* Systemically unwell
* Sudden/ severe loss of hair
* Uncontrollable itching
* Herpetiform lesions
* Other symptoms – e.g. joint pain/ night sweats
* Recently returned from travels
* Affecting mucus membranes
* Suspected meningitis
* Non accidental injury/ bruising
* Suspected link with medication
26
At Risk Groups
* Babies and young children
* Elderly patients
* Pregnant women
* Immunocompromised patients
* Patients taking other medicines
* Patients with pre-existing skin conditions
* Patients with neuropathy
27
Treatment Principles
* Treat the underlying cause
* Preventative measures – emollients
* Topical or systemic therapy
* Consider the formulation
* Consider allergies/ sensitivities to excipients
* High concentration of paraffin = fire risk
* Application of multiple products
* Steroids dose – Finger tip unit (FTU)
28
Dry Skin
* Moisture content of the skin is reduced
* Causes small fine flakes and dry patches
* Itching is one of the most common symptoms of dry skin
* Dry skin may be a side effect of some medicines
29
Dry skin is more common in
* Colder winter months
* Elderly patients
* Hypothyroidism
* Patients with a history of eczema
30
Dry Skin Cycle
=> Itch => Scratch => Damaged Skin =>Release of Inflammatory Chemicals
31
Eczema = Dermatitis ?
* Dermatitis = inflammation of the skin
| * Eczema = acute/chronic, allergy/genetic
32
Types of Dermatitis
* Irritant contact dermatitis
* Allergic contact dermatitis
* Atopic eczema
33
Types of Dermatitis - Irritant Contact Dermatitis
=> direct damage caused by a provoking agent
| e.g. handling water, detergents, solvents or harsh chemicals and by friction
34
Types of Dermatitis - Allergic Contact Dermatitis
=> hypersensitivity of skin
when in contact with substances that most people don't react to
e.g. nickel, perfume, rubber, hair dye or preservatives
35
Types of Dermatitis - Atopic Eczema
=> chronic itchy skin condition - commonly
| prevalent in children
36
Eczema = Dermatitis ? Causes
```
• Irritants
e.g. detergent, soap, acid and alkalis (cement) and
oils
• Allergens
e.g. nickel, topical corticosteroids, cosmetics,
rubber, late and dyes
• Genetics
e.g. a family history of dermatitis
```
37
Dermatitis Signs + Symptoms
* Red, sore, itchy skin
* Papules and vesicles may appear
* Blistering
* Crusting
* Fissures
* Weeping
* Can be acute or chronic
38
Dermatitis Differential Diagnosis
* Psoriasis
* Fungal skin infections
* Pompholyx
39
Dermatitis Referral
* Widespread/ severe / broken skin
* Lesions on the face not responding to emollients
* OTC treatment failure
* Children under 10 years who need a steroids
40
Treatment for Dermatitis
```
Emollients
Steroids
Humectant
Antiseptics
Antipruritic
```
41
Emollients are
• Moisturisers
| => help soothe the skin and provide relief from itching and dryness.
42
Emollients mode of action
• Trap moisture in the skin and form a protective oily layer on the outer skin
surface.
=> helps the skin repair and improves skin hydration.
43
Steriods mode of action
• Reduce inflammation in the skin
44
Humectant
• Penetration skin layers + attract + retain h2o
| => h2o from the Dermis is moved to the Epidermis to hydrate the Stratum Corneum,
45
Antiseptics
• Slows or stops the growth of micro-organisms on external surfaces of the body + helps to prevent infections
46
Antiseptics help prevent infections because
=> When you itch you damage the skin barrier function + microbes can get into the skin causing an infection
47
Antiprutitic
• Relieves itching
48
Dermatitis Treatment
| - Emollients Active Ingredient + Pharmaceutical Product
```
=> Cetraben cream
• White soft paraffin
• Liquid paraffin
=> Diprobase ointment
• White soft paraffin
• Liquid paraffin
=> Balneum bath oil
• Soya oil
```
49
Dermatitis Treatment
| - Steriods Active Ingredient + Pharmaceutical Product
=> Hc45
• Hydrocortisone 1% (mild potency steroid)
=> Eumovate
• Clobetasone 0.5% (moderately potent steroid)
50
Dermatitis Treatment -
| Humectant Active Ingredient + Pharmaceutical Product
=> Hydromol intensive
| • Urea 10%
51
Dermatitis Treatment -
| Antiseptics Active Ingredient + Pharmaceutical Product
```
=> Dermol 500 lotion
•Benzalkonium chloride
• Chlorhexidine Hydrochloride
• Liquid Paraffin
• Isopropyl Myristate
```
52
Dermatitis Treatment
| - Antipruritic Active Ingredient + Pharmaceutical Product
=> Eurax
| • Crotamiton
53
Dermatitis Treatment Formulations
* Bath oil
* Cream
* Gel
* Lotion
* Oil
* Ointment
* Pastes
* Shower gel
54
Dermatitis Treatment Formulation - Ointments
• Greasy in nature
• They are usually made of White Soft Paraffin/ Liquid Paraffin
• Ideal for very dry or thickened skin + night-time application
• They do not usually contain preservatives (ingredients that help to protect the product from bacteria + increase its shelf-life)
=> + are therefore less likely to cause skin reactions
55
Dermatitis Treatment Formulation - Creams
• Contain a mixture of oil and water
Less greasy
• Easier to spread on the skin than ointments
• Should be used frequently and applied liberally to prevent the skin from drying out
• Creams usually come in a container with a pump dispenser
• Good for day-time application
56
Dermatitis Treatment Formulation - Lotions
* Contain the least oil and most water
* Least effective in moisturizing the skin
* They normally contain preservatives so may cause skin irritation
* Lotions are useful for hairy areas such as scalps
57
Seborrhoeic Dermatitis (Cradle Cap in Infants) Causes - Unknown
* Increased cell turnover - could be linked to immunological, hormonal, nutritional factors
* Malassezia ovale (which is a yeast) involved
* May be related to medication e.g. haloperidol, methyldopa, lithium, phenothiazines
58
```
Seborrhoeic Dermatitis (Cradle Cap in Infants)
Signs + Symptoms
```
• Cradle Cap = large yellow greasy scales which crust over
=> Can sometimes affect other areas too (e.g. face, ears and skin folds)
• Adults ranges from dandruff (not inflamed)to more severe inflamed condition
• More common in men than women
• No change in sebum production
59
Seborrhoeic Dermatitis Differential diagnosis
* Atopic Dermatitis
| * Psoriasis
60
Seborrhoeic Dermatitis Referral
* OTC treatment failure
| * Lesions are weeping, broken skin, widespread
61
Seborrhoeic Dermatitis Treatment
* Cradle cap = Dentinox cradle cap shampoo (Sodium lauryl ether sulphate), Olive oil
* Adults seborrheic dermatitis = medicated shampoos (can cause local irritation)
62
Seborrhoeic Dermatitis Treatment: Pharmaceutical Product, Active Ingredient , Mode of action
```
=> Nizoral
• Ketoconazole
• Anti-fungal & anti-dandruff
=> Selsun
• Selenium sulphide
• Anti-fungal & anti-dandruff
=>Polytar or Neutrogena T/Gel
• Coal Tar
• Antiseptic & anti-inflammatory action
=> Capasal Therapeutic Shampoo (coal tar & coconut oil)*
• Salicylic acid
• Keratolytic, reduces itchiness and dandruff
```
63
Systemic Illnesses Affecting the Skin – Infections
* Meningitis
* Measles
* Mumps
* Rubella
64
Systemic Illnesses Affecting the Skin – Infections
| Meningitis
* Stiff neck, headache, fever, drowsy
| * Blotchy red rash doesn’t fade when glass rolled over it
65
Systemic Illnesses Affecting the Skin – Infections
| Measles
* Cold like symptoms for 7-10 days before rash appears
| * Sore, red eyes that may be sensitive to light
66
Systemic Illnesses Affecting the Skin – Infections
| Mumps
• Painful swelling of the parathyroid glands (hamster face)
67
Systemic Illnesses Affecting the Skin – Infections
| Rubella
• Swollen glands and fever
68
Systemic Illnesses Affecting the Skin - Erythema Multiform Causes
* Adverse drug reaction (e.g. antibiotics such as tetracyclines, NSAIDs)
* Triggered by an infection (i.e. viral infection)
69
Systemic Illnesses Affecting the Skin - Erythema Multiform Symptoms
Rash – suddenly develops in a few days (starts on the hands and feet and
spreads to limbs, upper body and the face). Starts as small red spots which
can become raised. Patches look like a target (bulls-eye). Fades after 2-4
weeks.
• High temperature, headache, generally feeling unwell, achy joints
• Sores inside the mouth (make it hard to eat and drink)
• Sore eyes, sensitivity to light & blurred vision
• Sores on the genitals (makes urination painful)s
70
Systemic Illnesses Affecting the Skin - Erythema Multiform - Treatment
* Stop the medicine which may be triggering the reaction
* Antiviral tablets (if caused by a viral infection)
* Antihistamines (to reduce itching)
* Emollients (to reduce itching)
* Steroid cream to reduce redness and swelling (inflammation)
* Pain relief
* Anaesthetic mouthwash to ease the discomfort of any mouth sores
* Antibiotics – if a bacterial infection develops
71
Adverse Drug Reactions Affecting the Skin -
| Stevens Johnson Syndrome (SJS)
* Flu like symptoms
* Red-purple rash that quickly spreads and forms blisters
* Skin dies and peels off
* Medical emergency
72
Medicines which cause Stevens-Johnson Syndrome SJS:
* Allopurinol
* Carbamazepine
* Fluconazole
* NSAIDs (e.g. Ibuprofen)
* Paracetamol Phenobarbital
* Phenytoin
* Sertraline
73
Adverse Drug Reactions Affecting the Skin -
| Toxic Epidermal Necrolysis (TEN)
* Prodromal symptoms (fever, sore throat, conjunctivitis)
* Red, burning/ painful rash
* Spreads across the body
* Hair and nails may be shed
* Epidermis layer peels off
74
Medicines which cause Toxic Epidermal Necrolysis (TEN)
* Allopurinol
* Ampicillin
* Anti-convulsants (carbamazepine, phenytoin)
* Corticosteroids
* NSAIDs
