The Skin in podiatry

Question 1

Describe what the Integumentary system is and what it is comprised of

Answer 1

The Integumentary system in simple terms is a set of organs which form the outermost layer of the human body. It comprises the following:

• Skin
• Hair
• Nails
• Glands
• Nerves

Question 2

Describe the structure and function of the skin

Answer 2

The skin consists of 3 main components, these being:

• The Epidermis
• The Dermis
• The Dermoepidermal junction

Question 3

Detail the charecteristics of the Epidermis

Answer 3

• Epidermis is Avascular (Has no blood vessels)
• Outermost layer of the skin which forms primary Protective layer for the body (waterproof barrier)
• Made up of three types of cells Keratinocytes, Melaninocytes and Lagerhans
• Produces new skin cells via the Stratum Basale Layer

Question 4

What are Keratinocytes

2 answers

Answer 4

Keratinocytes - Highly specialized cells which produce the protein keratin in order to form a protective barrier and stop foreign substances form entering the body. They also play a structural role in the skin forming tight bonds with other cells in order to maintain them in place

Question 5

What are Melanynocytes

Answer 5

• Melonynocytes produce the protein kown as melanin which is responsible for the skins pigment.
• Melanin protects against UV radiation

Question 6

What are Lagerhan Cells

Answer 6

• Lagerhan cells are a form of dendretic cells (Antigen presenting cells) which perform phagocytoses (ingest and eliminate foreign substances) protecting against microorganisms and foreign substances.
• They are most common in the Stratum spinosum layer
• After performing phagocytoses the transport portions of the microbe they ingested to the cell membrane presenting it to other immune cells helpin to stimulate immune reactions

Question 7

What is acute inflammation

Answer 7

• Acute inflammation is an immediate to infection or tissue damage
• It is short in duration lasting from minutes to several days depending on severity

Question 8

What are the clinical features of inflammation

Answer 8

• Redness (Rubor)
• Heat (Calor)
• Swelling (Tumor)
• Pain (Dolor)

Question 9

What are the main affects of Chemical/Inflammitory Mediators associated with inflammation

Main features of inflammtion there are 2

PP IG

Answer 9

• Vasodialation - widening of blood cells to enhance blood flow to areas lacking oxeygen and/or other nuetrient (Redness and Heat)
• Increased blood vessel permiability that allow plasma proteins and immunogloblins to pass easily through tissue (increased fluid causes swelling)

Question 10

What is the mainsaty treatment for acute inflammation

Answer 10

• R - Rest
• I - Ice
• C- Compression
• E - Elevation
• (This should be adapted for different patients and situations)

Question 11

Define Chronic Wound

Answer 11

• Wounds that fail to procceed through normal stages of wound healing in an orderly and timely manner
• Normal Stages - Haemostasis, Inflammation, proliferation and remodelling)

Question 12

Define Aetiology

Answer 12

The cause of a disease or condition

Question 13

Detail the numerous steps to the assessment of a chronic wound

Answer 13

Patient History - General assesment of the patients current health status and an in depth look at patient history to determine any medical comorbidities (having 2 or more medical conditions at the same time) and contributing factors

Nuerological and vascular assessments - In order to help identify wound aeitology (Cause of a disease/condition)

Tissue Viability Assesment - to identify presence of any infection e.g. necrosis (Death of tissue), Erythema (Red skin rash), Gangrene (loss of blood supply causing tissue to die)

General Skin Viability - Depth, Size, Site, Odour and apperance of peri wound (tissue around the wound . Nature of the wound margins, base of the wound and the amount and type of exudate should all be assessed.

Question 14

What is Osteomyelitis

Answer 14

Osteomyelitis is an infection in the bone causing pain and discomfort.

Infection reach the bone by travelling through the bloodstream or spreading from nearby tissue.

Question 15

Define Pathogenesis

Answer 15

Development of a disease or condition (the process by which a disease or condition develops)

Question 16

Describe the pathogenesis of Chronic wounds (The proccess by which an infection lead to a disease)

Answer 16

The normal inflamatory proccess is distrupted and a particular set of physiological traits occur:

• Increased levels of Pro Inflamatory cytokines (Cytokines that favour inflammation) (Cytokines are secreted proteins which aid cell to cell communication in immune response)
• High levels of reactive oxeygen species (Unstable molecule which contains oxeygen and easily reacts with other molecules in a cell causing damage to dna rna and cell death)
• High levels of bacteria colonization

Question 17

Describe Atrophy of the skin and its characteristics

Answer 17

• Degradation of and thinning of the Dermis/Epidermis
• Thin mechanically weak with poor viability (will struggle to heal when damaged)
• Atrophic skin lacks nutrition due to poor blood supply

Question 18

What is systematic bacterial infection

Answer 18

SEPTICEMIA CAUSES EPC

• Septicemia is a bacterial infection which has spread to the bloodstream
• It can cause Erythemea (REDNESS) and Scaling in the skin
• Prutitus (Itching)
• Cellulitis (Deep localised spreading infection)
• Rapidly result in organ faliure

Question 19

What is Staphylococcus Aures its features and the resulting conditions

Answer 19

• Bacterial infection often affecting the skin
• Results in demarcated (line/boundary seperating infected and healthy skin) yellowish skin pustules caused by formation of a fibrin wall in the outer edges of the area containing pus (wall of fiborous non globular protein involved in clotting)
  *

Question 20

What is Beta Haemolytic streptococci its features and resultant conditions

Erysipelas

Answer 20

• A form of bacteria which can cause skin infections
• Causes Erysipelas (infection of the upper layers of skin, Red rash with raised edges)
• Wounds infected with Beta Haemolytic Streptococci show an eroded margin and straw to yellow coloured exudate due to bacterial production of enzymes such as hyraluronidase

Question 21

What is Corynebacterium minutissium

Answer 21

• Bacteria causing erythrasma (moist interdigital fissuring) particularly associated with sweating therefore is treated by primarily controlling sweat

Question 22

What is Pseudomonas aeruginosa

Answer 22

Gram Negative (Gram Test is used to check for bacteria and consists of applying a stain to bacteria to identify specifc bacterium) aerobic rod shaped bacterium which cause skin damage.

Causes greenish pigment that discolours the skin and dressings

Question 23

Detail the numerous management stratagies for dealing with a bacterial skin infection

……..diazine and flucloxacillin

Answer 23

• Topical antimicrobial - This may be used for mild infection e.g. silver sulfadiazine cream/dressing, polyhexamethylene biguanide/PHMB, Iodine dressing.
• Moderate to severe infection - First line braod spectrum antibiotics e.g. flucloxacillin (cellulitus/wounds) co amoxiclav for diabetic wounds

Question 24

Describe what Veruccae/Warts are

What do they cause

4 answers

Answer 24

• Caused by HPV Human Papilloma Virus
• Virus causes hyperplasia (enlargement of tissue caused by Increase in cell reproduction rate) of the stratum spinosuum.
• Verrucae are often asymtematic in non immune compromised individuals

HPV’s causing warts in the foot include:

• HPV1 -Single, deep plantar warts
• HPV2 - Mosaic Warts
• HPV2, 4, 60 - Raised Warts

Question 25

What are Caustics

Answer 25

Caustics are hydroxides of light metals/acids used to remove dead tissue and destroy warts.

Question 26

Describe the clinical features of warts (single Plantar wart/ Verrucae) 6 answers

Answer 26

* New Warts can be mistaken for seed corns or foreign body under the skin * Established verrucae are rough (cauliflower like surface) sometimes with black dots * Black dots (thrombosed Papillae) * Verrucae appear encapsulated and when pinched cause a sharp pain * Pain can appear in plantar warts as a throbbing when standing * Regressing warts show black dots

Question 27

What are the five layers of the epidermis In order (Deepest layer first)

Answer 27

Stratum Basal Stratum Spinosum (Squamus Layer) Startum Granulosum Stratum Lucidium Stratum Corneum

Question 28

What is the Stratum Basal Layer Detail its properties 3 answers clue = germinate what cells are present = M M

Answer 28

* Innermost (deepest) layer of the epidermis * Also called Stratum Germinativum (as constantly germinating producing new cells) * Contains Melaninocytes (skin pigment melanin producing) and Merkel Cells (mechanorecptors associated with touch)

Question 29

What is the strartum spinosum detail its properties Basal cells - keratinocytes 5 answers

Answer 29

* Squamous layer “spiny layer” due to the fact that cells are held together by spiny like projections * Responsible for cytokin synthesis (protien that helps regulate immune response * Thickest layer of the epidermis * Contains Lagerhans (antigen presenting cells) and Keratinocytes * Made up of basal cells which have matured into squamus cells known as keratinocytes (keratin producing cells)

Question 30

What is the Stratum Granulosum, detail its charecteristics clue = kerathylin granules 3 answers

Answer 30

* Contains Keratinocytes which have moved up from the spinosum layer * Keratinocytes contain kerathylin granules which promote cell dehydration * As the cells move further toward the surface of the skin they begin to flatten out and dehydrate adheing to one another making them more tough and durable

Question 31

What is the Stratum Lucidium clue = lucid/clear 3 answers

Answer 31

* Keratinocytes from the granulosum migrate to the lucidium layer dying and in the process forming the stratum lucidium * Lucidium is clear transparent layer when viewed under microscope * This layer is mainly found on hariless parts of the body where skin is the thickest (palms of hands, soles of feet)

Question 32

What is the stratum Corneum detail its charecteristcis clue = corneocytes 4 answers

Answer 32

* Uppermost layer of the epidermis * Contains Dead Keratinocytes known as corneocytes (cornified cells) * Corneocytes are deviod of most water and have no nucleus * Cornoecytes serve as hard protective layer against trauma and are eventually shed into the enviroment as dandruff or dust

Question 33

What is the bodies biological response to acute inflammation, list the steps 5 steps

Answer 33

Neutrophils,Microphages,Lymphocytes,Fibroblasts,Ephthelial cells * Initially Neutrophils arrive (White blood cells,immune system first line of defense) * Followed by Macrophages (engulf foreign materials and initiate immune response) * Lymphocytes (white blood cell that produce antibodies to attack bacteria, virus, toxins) and fibroblasts (secrete collagen and help with wound healing) * Epithelial cells migrate on from wound edges over newly laid dermis and healing is complete

Question 34

List the Topical treatments available for plantar warts 4 answers MTS acid S N

Answer 34

* Monochloroacetic acid - corrosive acid based solution * Trichloroacetic acid - same as mcaa but more commonly used as 10% solution * Salicylic Acid - solution applied on a daily bases to peel off the upper layer of warts tissue * Silver nitrate - paint on solution, file down or etch the wart with scalpal first

Question 35

What is Electrosurgery in regards to warts

Answer 35

* Local anaesthetic is applied to the foot * An electric current delivering a lot of heat cauterises the wart burning it off and essentially killing unwanted growth

Question 36

What is vitaligo

Answer 36

Abnormal pigmentation of the skin

Question 37

What is Hemostasis

Answer 37

Hemostasis is the proccess of a wound being closed by clotting * Blood vessels constrict limiting blood flow (Vascular Spasm) * Platlets stick together in order to seal the damaged blood vessel (Platelet Plug) * Coagulation occurs reinforcing the platelet plug with threads of fibrin which a binding molecules

Question 38

What is the inflammation phase of wound healing

Answer 38

* 2nd stage of wound healing after hemostasis and controls bleeding and prevents infection * The fluid engorgement allows healing and repair cells to move to the site of the wound * Damaged cells, pathogens, and bacteria are removed from the wound area

Question 39

What is the Proliferation stage of wound healing

Answer 39

* Wound is rebuilt with new tissue made up of collagen and extracellular matrix * Miyofibroblasts cause the wound to contract and new blood vessels are constructed so that granulation tissue (red bumpy tissue showing the wound is progressing from inflammatory phase) can be healthy * Finally epithelial cells resurface the wound (epithelial cells line the surface of the body

Question 40

What is the remodeling phase of wound healing

Answer 40

* Also called maturation phase * Cells used to repair the wound that are no longer needed are removed by apoptosis (programmed cell death * Collagen is remodelled so the fibres lie closer together and cross link (reduces scar thickness and makes skin stronger)

Question 41

What is Hyperkaratosis

Answer 41

Increased thickening of the skin (The Stratum Corneum layer of the epidermis)

Question 42

What are Corns and Callus

Answer 42

Corn - inverted cone of hyperkeratinised tissue that is pushe into the skin Callus - Yellowish plaque of hard skin Both are associated with excessive mechanical stress e.g. friction, pressure torsion tension.

Question 43

What is the pathogenesis of corns and callus

Answer 43

Both corns and callus develop as a response to mechanical stress In response to repetitive friction and pressure thickening (keratinisation) takes place as well as a reduced rate of desqumation (peeling of the skin)

Question 44

What is Burstitis

Answer 44

Bursitis is basically inflammation of the bursa (fluid filled sac the cushions and lubricates bones and joints)