Integumentary System Flashcards
1
Q
Skin Facts (6)
A
- Forms the integumentary systems
- Largest Organ of the human body
- 2sqm2
- 0.5 -4mm thickness
- Covers external body and continues with mucous membrane internally
- Epithelial membrane -> Cutaneous membrane
- Contains accessories structures : Glands, hair & nails
2
Q
Skin Structure - 3 Main Layers
A
- EPIDERMIS : Superficial layer of skin formed epithelial tissue ( tightly packed together )
- DERMIS : connective tissues + accessory structures ( Sweat glands, hairs , sebaceous glands )
- SUBCUTANEOUS / ADIPOSE LAYER : Insulating & protective layer of fatty tissue. Connects the dermis to deeper lying muscle & Bone
3
Q
Epidermis Overview
A
- Formed of keratinised epithelium ( Protective & waterproofing )
- varies in thickness
- Interstitial fluid provides O2 & nutrients to cell via slow diffusion -> drained by lymph
- Avascular ( no blood vessels) & no nerves ending
- Attached to dermis by a basement membrane ( glue )
- takes 40 days to replace epidermis
4
Q
Journey of keratinocyte
A
- Produced at the bottom of epidermis and move up towards the surface -> become flattened
- They accumulate a protein call keratin on their journey to the surface ( waterproof)
- Suffocate cell from inside
- Cell die and end up on the surface of our skin
5
Q
Epidermis Cells
A
- Keratinocytes (90%)
- Though fibrous protein that protects from heat , microbes & chemicals - Melanocytes (8%)
- Synthesize melanin. Melanin is a pigment that contributes to skin colour and absorbs UV light .
- Surround nuclei of keratinocytes ( Barrier - protect DNA )
- 2 types of melanin : eumelanin ( brown black ) / pheomelanin ( reddish yellow ) -> fair skin less melanin protection - Langerhans cells (2%) :
- Ingesting foreign invaders.
- immune cells involved in skin surveillance ( antigen - presentation )
Bonus : By shedding dead cells from our skin we are also removing colonies of bacteria that are living on the skin
6
Q
Fingerprints
A
- Develop 3rd month of foetal development
- Ridges between dermis & epidermis create fingerprintes
- Increase surface area & enhance grip by creating friction
- Unique -> pressure in the womb
7
Q
Epidermis 5 Layers
A
- Stratum Corneum
- Stratum lucidum
- Stratum Granulosum
- Stratum Spinosum
- Stratum Basale
8
Q
Stratum Corneum
A
- Can be thin or Thick
- 25-30 layers of flattened dead keratinocytes
- cytoplasm replaced by keratin
- Are shed ( desquamated )
9
Q
Stratum lucidum
A
- 3-5 layers of dead skin
- only present in thick skin ( hands / feet )
10
Q
Stratum granulosum
A
3-5 layers of cells undergoing apoptosis ( cell suicide )
11
Q
Stratum spinosum
A
8-10 layers of new keratinocytes
12
Q
Stratum basale
A
Single row dividing to form new keratinocytes
13
Q
Skin Colour [BROWN]
A
- Pigmentation due to varying degrees of melanin produces by melanocytes
- Different race have same # of melanocytes but different amounts & types of melanin ( eumelanin / pheomelanin )
14
Q
Skin Colour [PINK]
A
Color due to Blood Circulation & Oxyhaemoglobin (Red)
15
Q
Skin Colour [NATURAL YELLOW]
A
Caused by Carotenes
-> If Yellow and not eating lot of carotenes -> issue converting it into Vit A
16
Q
Skin Colour [ YELLOW]
A
Pathology due to bilirubin ( Jaundice , cyanosis )
17
Q
Skin Colour [ PALE / FRECKLES ]
A
- Albinos unable to synthesise melanin
- Could indicate anaemia
Freckles : uneven distribution of melanocytes
18
Q
Dermis Definition
A
Thickest layer of the skin formed of connective tissue & accessory structures - Contains matrix of collagen (strength) & elastic fibers ( stretch & recoil )
19
Q
Sweat (sudoriferous) Glands
A
- Consist of a gland , duct & pore. Located next to a capillaries to receive secretion .
- Most numerous in palms , sole of feet, axillae & groin
20
Q
Sweat Composition
A
Urea ( Waste excretion ), Na+ ( sodium ) & Salt.
Excessive sweats leads to dehydration & sodium depletion -> Need Sodium ( Jungle trek example )
Tip : Water with electrolyte including sodium if activity with lot of sweating ( hot yoga , sauna ,.. )
21
Q
Sweat Smell
A
Created by action of bacteria breaking down substances in sweat ( like fatty acids )
Note : Western countries smell more as too much cleaning / soap remove good bacteria -> vicious bacteria left eating sweat and turning them into sticky compound
22
Q
Sensory Nerve Ending
A
- Meissner’s corpuscule (near surface) : sensitive to light pressure
- Pacinian corpuscule ( deep) : sensitive to deep pressure
- Free nerve ending : sensitive to pain & temperature
1 Nerve root for all -> Deep pressure for injection so nerve ending not able to send pain message
23
Q
Dermis contains
A
- Arterioles & capillaries -> thermoregulation
- Lymph vessels & sensory nerves ending
- Sweat & sebaceous glands , hairs & Arrector pili ( smooth muscle that erect hair follicle )
- Fibroblasts ( making collagen & fiber )
- Immune cells : Macrophages & mast cells
24
Q
Dermis : Hairs
A
Columns of Dead keratinized cells bond together by proteins
- Color is genetically determined , hormone influence distribution
- Contains melanin pigment ( more = darker , grey = no production )
- Hair shaft determine shape of hair (round=straight, oval / flattened = curly )
25
Arrector pili
Microscopic band of smooth muscle that connect Hair follicle to dermis.
When hair is erect , traps a layer of hair next to skin => thermoregulation
26
Dermis : Sebaceous Glands function
Secrete sebum which keeps hair soft & provides waterproofing for skin + anti microbial
- Located on face , scalp , lips , eyelids, nipples , labia folds & penis glands
- Activity increase during puberty (increase serum production -> traps in pore -> pimple )
- Fatty Acids in serum -> inhibits bacterial growth
-
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Skin Function (6)
1. Protection
2. Thermoregulation
3. Vitamin D Production
4. Sensation
5. Absorption
6. Excretion
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Protection
Against dehydration & external factors such as chemicals , toxins , trauma , light & microbes.
29
How does the skin provide protection ?
1. Physical Barrier : Thanks to closely packed keratinized cells and melanin
2. Sebum : Contains fatty acids which inhibit microbial growth
3. Sweat : contains lysozymes which are enzymes that break down bacteria
4. Desquamation : shedding of skin cells helps remove microbes
5. Nerve sensors : induce protective reflexes
30
Thermoregulation : Homeostasis , Variation and control center
- Body Temperature 36.5 - 37.5 , changes in evening ovulation , exercise
- Hypothalamus & medulla oblongata control center
31
How does the skin regulate temperature ?
1. Via Activity of sweat glands ( water evaporates off the skin )
2. Activity of blood vessels :
- Vasodilatation : arterioles in dermis
- Vasoconstriction : vessels in internal organs -> more blood to the surface
=> Both stimulated by ANS
32
Sweat Process
Sweat gland secrete sweat on to the skin surface. Evaporation of sweat cools the body.
- High Temperature : Vasodilation of peripheral blood vessels to promote heat loss ( Blood closer to surface )
- Low Temperature : vasoconstriction of peripheral blood vessels to prevent heat loss ( Blood closer to our core )
33
Thermoregulation : Heat production / Heat loss in the body
- Heat production : by liver , muscles & digestive organs. Adipose tissue is an insulator
- Heat loss : By respiration ( convection & evaporation )
34
Hypothermia
- Temp <35C
- Core temp drops below that required for normal metabolism & Body functions
- Death < 25C
35
Hyperthermia
- Core Temp elevates above>38.5C
- 40C -> life threatening
- 41C-> Brain death
- 45C ->Death
36
Vit D Formation
ONE OF THE MOST IMPORTANT FUNCTION
- Uv light activates a Vit D precursor in the skin : 7-dehydrocholesterol (converted to Vit D by sunlight )
- Kidney convert it into calcitriol
- Calcitriol : Act as an hormone to incrase Calcium + phosphorus uptake from food into blood -> support bone density
- Stored in Liver
VIT D Note :
1.Right angle to make Vit D -> Shadow shorter than us
2.Vit D deficiency south / Northern latitude in Winter ( Uk : End Sep - May )
Best time : Midday Sun for few minutes without protection (15-20 min )
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Absorption
- Lipid Soluble Molecule : Vit A, D,E,K, medication , essential oils , O2 & CO2
- Toxins : Acetone ( nail polish ) , Lead & Mercury , arsenic , poison oak & ivy , cosmetic
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Excretion
- Salt
- Water
- Urea
-Ammonia
Note : If detoxification system overwhelmed ( liver , constipation ) trying to use the skin as an exit route
39
Wound Healing - Superficial Wound ( Epidermis only )
Carpet burns - Abrasions & Burns
1. Basal cells move across the gap until contact inhibition occurs ( cessation of cell division in cells that touch each other )
2. Epidermal growth factor causes multiplication of the basal cells until space is filled
40
Wound Healing - Deep Wound
```
Affect Dermis & Subcutaneous Layer
3 phases :
1. Inflammatory Phase
2. Proliferative phase
3. Remodelling Phase
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41
Wound Healing - Inflammatory Phase
- Migration of leukocytes to clean up any microbes and foreign tissue
- Blood clot forms and becomes a scab (croute)
- Epithelial cells migrate to repair the basement membrane
42
Wound healing - Proliferative Phase
- Granulation tissue is formed with the laying of collagen and blood vessels.
- Extensive growth & Repair of epithelial cells
43
Wound Healing - Remodelling phase
- Can take 3 weeks to 6 months
| - Scab comes off naturally and scar tissue remains ( fibrosis )
44
Scar Tissue
A mark left on the skin or other body tissues where a wound , burn or sore has not healed completely and fibrous connective tissue has developed
Contains denser collagen fiber ( less elastic ) - fewer hairs glands , nerve endings & blood vessels ( hence whiter )
45
2 Types of scar tissues
1. Hypertrophic scar : Stays within boundaries of the wound & Flat
2. Keloid Scar : Larger space than the wound ( raised )
46
Skin Pathologies
| SKIN LESIONS
Abnormal / damaged tissue with impaired function of skin
47
Skin Pathologies - Papule
CIRCUMSCRIBED PALPABLE ELEVATION - NO FLUID
Small , firm , elevated lesion
- Circumscribed , solid elevation of skin with no visible fluid.
- Brown , purple, pink or red in color
- maculopapular rash
48
Skin Pathologies - Pustule
INFLAMMED LESION FILLED WITH PUS
| Purulent material -> necrotic inflammatory cells - Can be red or white
49
Skin Pathologies - Macule
FLAT CIRCUMSCRIBED LESION - ALTERATION IN SKIN COLOR ( non-palpable )
Freckles
50
Skin Pathologies - Nodule
SImilar to Papule but bigger & Deeper ( RA)
| May be filled with inflamed tissue or fluid - Verrue
51
Skin Pathologies - Crust
Collection of dried body fluid ( blood plasma and exucrate ) & dead skin cells ( scab )
52
Skin Pathologies - Lichenification
Thick dry rough Plaques of thickened skin
Visibile thickening of epidermis with pronounced lines
Hallmark of chronic eczema / dermatitis or excessive scratching
53
Skin Pathologies - Erosion
Shallow moist cavity in the epidermis
Wearing away with loss of superficial epidermis ( from chemical , friction or pressure
Ulcer in diabetes ( carpet burn )
54
Skin Pathologies - Keloid
Abnormal scar tissue that grows beyond the skin boundary . Strong genetic links
55
Skin Pathologies - Comedone ( Acne )
- Blackhead , whitehead or red bumps due to excess sebum , keratin & debris forming a plug in the sebaceous duct of a hair follicule
- Hormones such as testosterone can cause more & thicker oil secretions that block pores
56
Skin Pathologies - Comedone - Blackhead
Open Comedo = Blackhead ( acne vulgaris )
| If oil is open to air , it will oxidise and turn dark
57
Skin Pathologies - Comedone - Whitehead
Closed comedo = Whitehead
| If skin has grown over oily material , it remains whit
58
Eczema / Dermatitis
| Definition
The term Eczema & Dermatitis are interchangeable
| Very common chronic , pruritic ( itchy ) , inflammatory skin condition
59
Eczema / Dermatitis
| Signs & Symptoms & Complication
- Flaky, dry , oedematous
- Erythematous (red) oruritic , creusty mostly on flexor surfaces and joints
Complications : Secondary bacterial infections
60
Contact Dermatitis - Definition
Acute inflammation of skin caused by direct contact with an agent. Dividev into :
1. Irritant (80%)
2. Allergen (20%)
61
Irritant Contact Dermatitis (ICD)
Non Specific inflammatory reaction to a susbustance contacting the skin
Irritation happens where you've been in contact with the irritant
Phototoxic dermatitis : Topical ( ie perfumes ) or ingested irritant are activated by exposure to UV rays.
62
Allergen Contact Dermatitis ( ACD)
- Type IV delayed hypersensitivity reaction ( within 72 hrs )
- Pruritic erythematous rash
- Can occur with various chemicals ( rubber, metal - nickel )
- Photoallergic contact dermatitis : Substance becomes allergic only after structural change triggered by UV light ( ie sunscreens )
63
Contact Dermatitis - Signs & Symptoms
- Location of symptoms -> clue to the irritant / allergen
-Pruritic rash , burning , stinging, eroded, blistered skin
ICD : Quicker onset of symptoms ( ulceration , burning ) vs ACD ( pruritis significant )
64
Contact Dermatitis - Treatment
Finding trigger + Calming Symptoms : Topical calendula , chikweed , St John's wort , Aloe Vera
65
Atopic Dermatitis / Eczema - Definition
Immune mediated inflammation of the skin due to the interaction between genetic & environmental factors
- Pruritus primary symptoms
- infancy / childhood-> urban area + developed countries
Common Allergen : Foods , airbone ( dust , moulds, pollen )
Family history (2/3) , Asthma or allergic rhinitis
66
Atopic Dermatitis / Eczema - Pathophysiology
- Genetic weakness in epidermal barrier function
- Mutation in filaggrin gene ( structural protein in stratum corneum )
- Loss of filaggrin = impaired skin's barrier function leading to entry of foreign environmental substance that may trigger immune response
- Skin might be deficient in ceramides ( fatty acid ) increasing transepidermal water loss
- IgE (70-80% -> allergy )
Filaggrin keep our cells together tighly.Dry skin loose ceramid.
->If filaggrin missing -> Cells not tightly packed together -> irritant & allergens get in , disrupting skin immune system & creating inflammation & itching => Scratching => further compromise skin barrier => microbes ++
67
Atopic Dermatitis / Eczema - Signs & Symptoms
- Red scaly lesions on FLEXOR SURFACES & Cheeks , Very itchy
- Lichenification
- Infection on skin ( inflamed + pus)
68
Atopic Dermatitis / Eczema - TReatment
Identify allergen , avoiding skin irritant
2 Angles :
1. Help support immune system to be more tolerant
2.Help skin barrier to work properly
=> DIET - Elimination diet
=> Inflammation + Immune system : Quercetin , Vit D , Probiotics ( GIT health )
Allopathic : Corticosteroid
69
Urticaria ( Hives) - Definition + Pathophysiology
Itchy , red Blotchy & Raised rash resulting from swelling of the superficial skin
- Can develop in & out of the pharyngeal mucosa causing swelling & obstruction
-Occurs due to release of histamine from mast cells
Cause : Medication , allergies , food, stings ,stress
70
Urticaria ( Hives) -Treatment
Immune Support , Cause , Elimination diet , Lower histamine , Vit C ( Similar to Eczema except histamine )
71
Psoriasis - Definition + Pathophysiology
Chronic , Auto immune inflammatory skin disease
Stratum Basale is diving too quicly making abnormal keratin -> Stratum corneum renewal 7 days vs 40
Silvery Scales & flakes due to reduce shedding an accumulation fo stratum corneum
-> Cells not fully matures , didn't accumulate enough keratin to die => Plaques
72
Psoriasis - Causes
- Auto-immune : T-Lymphocyte mediated hyperproliferation of keratinocytes.
- Environmental , genetic & immunologic factors
=> susceptibility might be due to genetic defects in detoxification enzymes.
Triggers : Infection , chemicals , alcohol , stess ,beta-blockers
73
Psoriasis - Naturopathic Causes
Leaky Gut , poor digestion , altered immunity.
Driven by Auto-intoxication => poor digestion => Food putrfying / rotting in intestines => Creates polyamines => Leaky Gut => Allow content of disgestive system ( microbes , undigested food ) to interact with immune system. Influx of antigens => IS overwhelmed & liver is triggering immune system.=> PSORIASIS
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Psoriasis - Signs & Symptoms
- Red scalpy plaques covered with overlapping silvery shiny scales ( may bleed )
- Extensor surface ( wrist , elbow, knees ) & Scalp
- Arthritis (14% -> Auto immune )
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Psoriasis - Treatment
- Diet : Digestion , Gut Health , Semi-vegan diet , no Dairy or gluten , anti inflammatory , anti- oxydant => Juice fasting ( Heal & Seal )
- Gastro intestinal support , probiotics
- Detoxification , liver support
- Aloe vera , Epsom Salt Baths
76
Acne Vulgaris : Definition + Pathophysiology
Blockage of sebaceous / hair follicle duct.
- Male and puberty
- Oil normally drained to skin surface gets blocked by excess skin cells inside of the follicle -> bacteria proliferation
- Face and Back + Chest
=> Lack of desquamation , left of the skin -> sebum becomes trapped + overproduction
Testosterone stimulate sebaceous glands ( Puberty )
77
Acne Vulgaris - Cause
- Environmental including diet ( western)
- Diet high in Glucose -> Insuline level + -> Oil production + -> Excess skin cell production in follicle.
Stimulation of testosterone production
Dairy -> IGF + Insulin +
=> EXCESS INSULINE
- Excess testosterone ( puberty )
-Hormonal imbalance
-Oily creams
78
Acne Vulgaris - Characteristic ( Signs )
- Closed comedones ( whiteheads ) -> Trapped sebum & bacteria below the surface
- Open comedones ( blackheads ) -> Oxidised lipids -> black
- Inflammatory acne
- Cysts : follicle rupture -> pustule / nodule
79
Acne Vulgaris - Treatment
- Hormone balancing
- Diet : WFPD , water
AVOID : Excess oild , processed food , Dairy , wheat
- Detox , skin hygience , Zinc , B5 , Aloe vera gel + Spray of colloidal silver ( control microbial growth )
80
Quick overview Skin Lesion
Papule : CIRCUMSCRIBED PALPABLE ELEVATION - NO FLUID
Macule : FLAT CIRCUMSCRIBED LESION - ALTERATION IN SKIN COLOR
Pustule : INFLAMMED LESION FILLED WITH PUS
Nodule : Similar to Papule but bigger & Deeper ( RA)
81
Acne Rosacea - Definition
Chronic inflammation of skin associated with vascular changes which results in flushing ( change in blood vessels structure becomes permanent )
Accompanied by seborrhoea ( excessive discharge of sebum )
More common in Women
82
Acne Rosacea - Signs & Symptoms
Facial flushing, seborrhoea ( oily skin ) with papule & pustules
83
Acne Rosacea - Cause
- Skin overreactive -> exaggerated vasodilatory response to hyperthermia
- H.Pylori (88%) & Gastrin ( Gastrin = h.pylori growth )
- environmental , cosmetics , medications , stress
84
Acne Rosacea - Treatment
- Treat digestive system ( lack of stomach acid )
- Identify food allergies , intolerance
- Support blood vessels : Vit C
- Aloe vera
85
Warts & Verrucas
- Benign proliferation of skin & mucosa caused by infection with Human Papillomavirus (2&4)
- Signs : Papular lesion with a coarse rouhened surface
- Treatment : Often disappear spontaneously : Antiviral herbs ( thuja , olive leaf , St John's Wort , lysine )
86
Skin Tags
Small overgrowths attached to skin by stalk
- Generally occurs in areas where skin rubs
- Skin colour or darker - can bleed when knocked - often drop off
- Associated with hyperinsulinemia -> PCOS or diabetes type 2 precursor
87
Vitiligo
Skin loses it's pigmentation due to loss of melanocytes.
Onset any age
Genetic susceptibility
Autoimmune link ( Langerhans cells proliferation may inhibits melanocytes proliferation )
Few options of therapy available
88
Burns - Defintion
Injury to skin or tissues causes by heat , cold electricity , radiation , chemicals
89
Burns - Signs & Symptoms
Necrosis -> Pain
| Electrical burn -> extend beyond tissue damage -> arrhythmia / fibrillation
90
Burns - Treatment
Allopathic : Skin graft , fluid & electrolyte replacement , pain management
=> Calorie requirement increase to heal
Natural :Manage small burn , aloe vera , calendula
91
Burns Classification
Schema
1st degree : Epidermis
2nd degree : All epidermis + some dermis
3rd degree : Extends to subcutaneous tissue
4th degree : Extends into muscles & tendons
92
Burns - Complications
- Dehydration -> Loss of water & plasma through skin surface
- Hypothermia -> Impaired thermoregulation & heat loss
- Hypovolaemic shock
- infection
- Renal failure : Urea & uric acid production that overwhelm the kidney
- contractures : scar tissue contracts distorting skin & impairing movement
