INTEGUMENTARY SYSTEM skin Components of the integumentary system Skin Hair Nails Glands.
Skin: The Integumentary System
description
Transcript of Skin: The Integumentary System
Skin:Skin:
The Integumentary SystemThe Integumentary System
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FunctionsFunctions
Provides a barrier against hazardous materials Provides a barrier against hazardous materials and pathogensand pathogens
Major receptor for the sense of touchMajor receptor for the sense of touch
Waterproofs the body and prevents fluid lossWaterproofs the body and prevents fluid loss
Helps the body synthesize vitamin D from Helps the body synthesize vitamin D from ultraviolet lightultraviolet light
IntegumentIntegument means “covering” means “covering”
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StructuresStructures
SkinSkin– Largest organ of the bodyLargest organ of the body– Approx 5 kg in the average humanApprox 5 kg in the average human– Dermat/o, cutane/oDermat/o, cutane/o mean skin mean skin
– Made up of two distinct tissue layers and an Made up of two distinct tissue layers and an underlying layer of fatty tissueunderlying layer of fatty tissue
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Skin LayersSkin Layers
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StructuresStructures
– EpidermisEpidermisOutermost layer of skinOutermost layer of skin
Consists of stratified squamous epitheliumConsists of stratified squamous epithelium
Top layers are flat overlapping cells that contain Top layers are flat overlapping cells that contain soft soft keratinkeratin (fibrous, water-repellant protein) – (fibrous, water-repellant protein) – form the waterproof barrierform the waterproof barrier
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StructuresStructures
Lower layer is the Lower layer is the basal layerbasal layer – produces the – produces the epithelial cells that get pushed toward the surface epithelial cells that get pushed toward the surface where they die and become filled with where they die and become filled with keratinkeratin
The dead cells slough off so new cells can The dead cells slough off so new cells can take their placetake their place
The basal layer also contains The basal layer also contains melanocytesmelanocytes that that produce produce melaninmelanin (the dark brown pigment that (the dark brown pigment that determines skin colour, produces freckles, and determines skin colour, produces freckles, and protects against ultraviolet light)protects against ultraviolet light)
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StructuresStructures
– DermisDermisAKA coriumAKA coriumContains connective tissue, blood and lymph Contains connective tissue, blood and lymph vessels, nerve fibersvessels, nerve fibers
– CollagenCollagen – tough, flexible, fibrous protein– tough, flexible, fibrous protein– Mast CellsMast Cells – respond to injury, infection, or – respond to injury, infection, or
allergy by releasing substances like histamine allergy by releasing substances like histamine and heparinand heparin
Provides a living substrate for the epidermis, and Provides a living substrate for the epidermis, and contains the accessory structures, such as hair contains the accessory structures, such as hair follicles, glands, and nerve endingsfollicles, glands, and nerve endings
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StructuresStructures
– Subcutaneous LayerSubcutaneous LayerConnects the skin loosely to the underlying Connects the skin loosely to the underlying musclesmuscles
Consists of loose connective tissue and adipose Consists of loose connective tissue and adipose tissuetissue
– SubcutaneousSubcutaneous means “below the skin” means “below the skin”
Provides a cushion against shock, and insulation Provides a cushion against shock, and insulation against temperature changesagainst temperature changes
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Accessory StructuresAccessory Structures
Sebaceous GlandsSebaceous Glands– Associated with hair folliclesAssociated with hair follicles
Except on palms of Except on palms of hands and soles of feet hands and soles of feet (most concentrated in the (most concentrated in the scalp)scalp)
– Secrete Secrete sebumsebum – an oily – an oily substance which lubricates substance which lubricates the skin and discourages the skin and discourages bacterial growth (it is slightly bacterial growth (it is slightly acidic)acidic)
Also helps to prevent Also helps to prevent water losswater loss
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Accessory StructuresAccessory Structures
Sweat GlandsSweat Glands– AKA sudoriferous glandsAKA sudoriferous glands– Tiny, coiled glands that secrete Tiny, coiled glands that secrete perspiration perspiration (sweat) (sweat)
to the body surfaceto the body surface
Most numerous on the palms of the hands, soles of Most numerous on the palms of the hands, soles of the feet, forehead, armpitsthe feet, forehead, armpits
Perspiration is composed primarily of water and Perspiration is composed primarily of water and some salt and waste productssome salt and waste products
Functions to excrete excess water and cool the Functions to excrete excess water and cool the bodybody
Hidr/oHidr/o means sweat means sweat– HidrosisHidrosis is the production of sweat is the production of sweat
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Accessory StructuresAccessory Structures
– Eccrine Sweat glandsEccrine Sweat glandsOpen onto the skin surface Open onto the skin surface and secrete through and secrete through openings called openings called porespores
Most numerous typeMost numerous type
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Accessory StructuresAccessory Structures
– Apocrine Sweat glandsApocrine Sweat glandsOpen into hair folliclesOpen into hair follicles
Most numerous in armpit and Most numerous in armpit and external genitaliaexternal genitalia
Substance secreted also Substance secreted also contains contains proteins and fatty acids which proteins and fatty acids which give it a yellow colourgive it a yellow colour
Respond to pain, emotional Respond to pain, emotional stress, sexual arousal, etcstress, sexual arousal, etc
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Accessory StructuresAccessory Structures
Hair (Hair (trich/o, pil/otrich/o, pil/o))– Columns made of dead protein cells Columns made of dead protein cells
filled with hard keratinfilled with hard keratin– Melanocytes in the follicle produce Melanocytes in the follicle produce
melanin which colours the hairmelanin which colours the hair– Follicle: sac that holds the root of the Follicle: sac that holds the root of the
hair (its shape determines whether hair (its shape determines whether hair will be straight or curly)hair will be straight or curly)
– Arrector pili – tiny muscle fibers that Arrector pili – tiny muscle fibers that contract to make the hair stand erect contract to make the hair stand erect (reduces heat loss through the skin)(reduces heat loss through the skin)
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Accessory StructuresAccessory Structures
NailsNails– Thin plates of keratinized cells that protect the end of Thin plates of keratinized cells that protect the end of
the the fingers and toesfingers and toes
– Nail Body: translucent, closely molded to underlying Nail Body: translucent, closely molded to underlying tissuestissues
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Accessory StructuresAccessory Structures
– Nail Bed: joins the nail body Nail Bed: joins the nail body to the underlying tissue and nourishes the nailto the underlying tissue and nourishes the nail
Very vascularized – givesVery vascularized – gives the nail its pink colour the nail its pink colour
– Root: fastens the nail to the finger or toe by fitting it Root: fastens the nail to the finger or toe by fitting it into a groove in the skininto a groove in the skin
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Accessory StructuresAccessory Structures
Free Edge: portion of the nail body not attached to the Free Edge: portion of the nail body not attached to the nail bed (white portion of the nail)nail bed (white portion of the nail)
Lunula: pale, half-moon shaped region at the root of Lunula: pale, half-moon shaped region at the root of the nailthe nail
– Part of the nail body that covers the matrix (active Part of the nail body that covers the matrix (active area where new cells form)area where new cells form)
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Accessory StructuresAccessory Structures
Cuticle: Narrow band of epidermis attached to the Cuticle: Narrow band of epidermis attached to the surface of the nail just in front of the rootsurface of the nail just in front of the root
– Protects the new cells as they growProtects the new cells as they grow
– Onych/o, ungu/oOnych/o, ungu/o mean nail mean nail
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Medical SpecialtiesMedical Specialties
DermatologistDermatologist– Specializes in diagnosing and treating Specializes in diagnosing and treating
disorders of the skindisorders of the skin
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PathologyPathology
Sebaceous GlandsSebaceous Glands– Acne vulgarisAcne vulgaris
Chronic inflammation of the Chronic inflammation of the skin characterized by skin characterized by pustular eruptions caused by pustular eruptions caused by an overproduction of an overproduction of sebumsebum
Most common type of acneMost common type of acne
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PathologyPathology
– ComedoComedoNon-infected lesion formed Non-infected lesion formed by the buildup of sebum by the buildup of sebum and keratin in a hair follicleand keratin in a hair follicle
– Closed = whiteheadClosed = whitehead– Open = blackheadOpen = blackhead– Deep = pimple (papule)Deep = pimple (papule)– Very deep = cystVery deep = cyst
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PathologyPathology
– SeborrheaSeborrheaAny condition that is characterized by an Any condition that is characterized by an overproduction of sebumoverproduction of sebumSeborrheic dermatitisSeborrheic dermatitis
– Inflammation that causes scaling and itching of Inflammation that causes scaling and itching of upper layers of skinupper layers of skin
– Ex extensive dandruff, cradle capEx extensive dandruff, cradle capSeborrheic keratosisSeborrheic keratosis
– Benign growthBenign growth– Has a waxy “pasted-on” lookHas a waxy “pasted-on” look– Often occurs in the elderlyOften occurs in the elderly
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PathologyPathology
Sweat GlandsSweat Glands– AnhidrosisAnhidrosis
Abnormal absence of sweatingAbnormal absence of sweating– HyperhidrosisHyperhidrosis
Condition of excessive sweatingCondition of excessive sweating– DiaphoresisDiaphoresis
Profuse sweatingProfuse sweatingDue to specific cause such as menopause, shock, Due to specific cause such as menopause, shock, extreme emotion, eating spicy food, etcextreme emotion, eating spicy food, etc
– MiliariaMiliariaAKA heat rash, prickly heatAKA heat rash, prickly heatItchy rash caused by blockage of the sweat glands Itchy rash caused by blockage of the sweat glands by bacteria and dead cellsby bacteria and dead cells
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PathologyPathology
– HairHairFolliculitisFolliculitis
– Inflammation of the hair folliclesInflammation of the hair follicles– Especially common on the limbs and in the Especially common on the limbs and in the
beard areabeard areaHirsutismHirsutism
– Presence of excessive facial and body hair in Presence of excessive facial and body hair in womenwomen
– May be hereditary or caused by hormone May be hereditary or caused by hormone imbalanceimbalance
AlopeciaAlopecia– AKA baldnessAKA baldness– Partial or complete absence of hair from where Partial or complete absence of hair from where
it usually growsit usually grows
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PathologyPathology
NailsNails– ClubbingClubbing
Abnormal curvature of the nailsAbnormal curvature of the nailsCan be hereditary, but may also be related to Can be hereditary, but may also be related to oxygen deficienciesoxygen deficiencies
– KoilonychiaKoilonychia““spooning” of the nailspooning” of the nailOften an indication of iron-deficiency anemiaOften an indication of iron-deficiency anemia
– OnychocryptosisOnychocryptosisAKA ingrown toenailAKA ingrown toenail
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PathologyPathology
– OnychomycosisOnychomycosisFungal infection of a nailFungal infection of a nailMay cause the nail to turn white, May cause the nail to turn white, yellow, green, or black, and yellow, green, or black, and become thick or brittlebecome thick or brittle
– OnychophagiaOnychophagiaAKA “nail biting”AKA “nail biting”
– OnycholysisOnycholysisLoosening of the nail from the nail bedLoosening of the nail from the nail bedOften due to infectionOften due to infection
– ParonychiaParonychiaInflammation and swelling of tissue around the nailInflammation and swelling of tissue around the nail
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PathologyPathology
Skin PigmentationSkin Pigmentation– AlbinismAlbinism
Inherited deficiency or Inherited deficiency or absence of pigment in the absence of pigment in the skin, hair, and irises due to skin, hair, and irises due to a missing enzyme a missing enzyme necessary for the necessary for the production of melaninproduction of melanin
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PathologyPathology
– MelanosisMelanosisAny condition of unusual deposits of black pigment Any condition of unusual deposits of black pigment in the skinin the skin
– VitiligoVitiligoLoss of melanin resulting in Loss of melanin resulting in white areas of the skin, white areas of the skin, usually the face and hands usually the face and hands (autoimmune disorder)(autoimmune disorder)
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PathologyPathology
BruisesBruises– PetechiaePetechiae
Pinpoint hemorrhages Pinpoint hemorrhages (less than 2 mm in (less than 2 mm in diameter)diameter)Sometimes result from Sometimes result from severe feversevere fever
EcchymosisEcchymosisLarger irregular area of Larger irregular area of purplish discolourationpurplish discolourationEx black eye, bruiseEx black eye, bruise
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PathologyPathology
Surface LesionsSurface Lesions– Pathologic change of the tissue due to injury Pathologic change of the tissue due to injury
or diseaseor disease– Described by:Described by:
AppearanceAppearance
LocationLocation
ColourColour
sizesize
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PathologyPathology
– CrustCrustAKA scabAKA scab
Collection of dried serum and cellular debrisCollection of dried serum and cellular debris
– MaculeMaculeDiscoloured, flat spot that is less than 1 cm in Discoloured, flat spot that is less than 1 cm in diameter (ex freckles, flat moles)diameter (ex freckles, flat moles)
– PapulePapuleSmall, raised, red lesion that is less than 1 cm in Small, raised, red lesion that is less than 1 cm in diameter – does not contain pusdiameter – does not contain pus
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PathologyPathology
– NoduleNodule
Solid raised lesion that is Solid raised lesion that is larger than 1 cm and deeper larger than 1 cm and deeper than a papulethan a papule
– PlaquePlaque
Scaly, raised area of closely Scaly, raised area of closely spaced papulesspaced papules
– Ex psoriasisEx psoriasis– ScalesScales
Flakes or dry patches of Flakes or dry patches of excess dead epidermal cellsexcess dead epidermal cells
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PathologyPathology
– VerrucaVerrucaAKA wartAKA wart
Small, hard, skin lesion causedSmall, hard, skin lesion caused by the human papilloma virus by the human papilloma virus
– WhealWhealAKA weltAKA welt
Smooth, slightly elevated area that Smooth, slightly elevated area that itchesitches
Often a symptom of allergic Often a symptom of allergic reaction or insect bitesreaction or insect bites
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PathologyPathology
Fluid-Filled LesionsFluid-Filled Lesions– AbscessAbscess
Closed pocket containing pus Closed pocket containing pus
Caused by bacterial infectionCaused by bacterial infection
– CystCystClosed sac just under the skin containing soft or Closed sac just under the skin containing soft or semisolid materialsemisolid material
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PathologyPathology
– PustulePustuleSmall, circumscribed lesion containing pusSmall, circumscribed lesion containing pusimpetigo, smallpox, etcimpetigo, smallpox, etc
– VesicleVesicleSmall blister containing watery Small blister containing watery fluidfluidLess than 0.5 cm in diameterLess than 0.5 cm in diameter
– BullaBullaLarge blister containing watery Large blister containing watery fluidfluidMore than 0.5 cm in diameterMore than 0.5 cm in diameter
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PathologyPathology
Through the skinThrough the skin– AbrasionAbrasion
Superficial layers of skin are scraped Superficial layers of skin are scraped or rubbed awayor rubbed away
– FissureFissure
Groove or crack in the skinGroove or crack in the skin– LacerationLaceration
Torn and jagged wound or Torn and jagged wound or accidental cutaccidental cut
– Puncture woundPuncture wound
Deep hole made by a sharp objectDeep hole made by a sharp object
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PathologyPathology
UlcerUlcer– Open lesion of the skin or Open lesion of the skin or
mucous membrane resultingmucous membrane resulting in tissue loss around the in tissue loss around the edgesedges
– Decubitous ulcer – pressure Decubitous ulcer – pressure ulcer or bedsoreulcer or bedsore
Area where prolonged Area where prolonged pressure causes tissue pressure causes tissue deathdeath
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PathologyPathology
DermatitisDermatitis– Inflammation of the skinInflammation of the skin
Usually involves redness, itchiness (pruritus), Usually involves redness, itchiness (pruritus), swellingswelling
– EczemaEczemaForm of dermatitis that occurs on the face, neck, Form of dermatitis that occurs on the face, neck, elbows, and kneeselbows, and kneesSkin is red, blistered, or oozingSkin is red, blistered, or oozingEventually can become scaly, brown, and Eventually can become scaly, brown, and thickenedthickened
– Contact DermatitisContact DermatitisLocalized allergic response caused by contact with Localized allergic response caused by contact with an irritant or allergenan irritant or allergen
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PathologyPathology
ErythemaErythema– Redness of the skin due to dilated capillariesRedness of the skin due to dilated capillaries
Ex blush, inflammation, sunburnEx blush, inflammation, sunburn
PyodermaPyoderma– Any acute, inflammatory, pus-forming bacterial skin Any acute, inflammatory, pus-forming bacterial skin
infectioninfection
IchthyosisIchthyosis– Group of hereditary disorders characterized by dry, Group of hereditary disorders characterized by dry,
thickened and scaly skinthickened and scaly skin– Ichthy/o means dry or scalyIchthy/o means dry or scaly
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PathologyPathology
LipedemaLipedema– Chronic swelling due to accumulation of fat and fluid Chronic swelling due to accumulation of fat and fluid
under the skinunder the skin– Commonly occurs between the calf and ankleCommonly occurs between the calf and ankle
PsoriasisPsoriasis– Skin disorder characterized by the occurrence of red Skin disorder characterized by the occurrence of red
papules covered by silvery scales on the elbows, papules covered by silvery scales on the elbows, knees, scalp, back or buttocksknees, scalp, back or buttocks
– Caused by an increase in the rate of basal cell growthCaused by an increase in the rate of basal cell growth
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PathologyPathology
RosaceaRosacea– Chronic, idiopathic conditionChronic, idiopathic condition– Produces redness, tiny pimples, and broken Produces redness, tiny pimples, and broken
blood vessels, often on the faceblood vessels, often on the face
SclerodermaScleroderma– Autoimmune disorderAutoimmune disorder– Connective tissues become thickened or Connective tissues become thickened or
hardenedhardened
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PathologyPathology
UrticariaUrticaria– AKA hivesAKA hives– Wheals caused by an allergic reactionWheals caused by an allergic reaction
XerodermaXeroderma– Dry skinDry skin
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PathologyPathology
Bacterial Skin InfectionsBacterial Skin Infections– Furuncles (Boils)Furuncles (Boils)
large, tender, swollen areas caused by infection large, tender, swollen areas caused by infection around hair follicles or sebaceous glandsaround hair follicles or sebaceous glands
– CellulitisCellulitisAcute, rapidly spreading infection within the Acute, rapidly spreading infection within the connective tissueconnective tissue
Symptoms include malaise, swelling, warmth, and Symptoms include malaise, swelling, warmth, and red streaksred streaks
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PathologyPathology
– ImpetigoImpetigoHighly contagious pyodermaHighly contagious pyoderma
Characterized by isolated pustules that become Characterized by isolated pustules that become crusted and rupturecrusted and rupture
– Necrotizing FasciitisNecrotizing FasciitisAKA flesh-eating bacteriaAKA flesh-eating bacteria
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PathologyPathology
Fungal Skin InfectionsFungal Skin Infections– TineaTinea
AKA ringwormAKA ringworm
Grows on skin, hair or nailsGrows on skin, hair or nails
Fungus spreads out in circle Fungus spreads out in circle leaving normal-looking skin leaving normal-looking skin in the middlein the middle
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PathologyPathology
Parasitic Skin InfectionsParasitic Skin Infections– ScabiesScabies
Caused by infestation with the itch miteCaused by infestation with the itch mite
Produces brown lines and an itchy rashProduces brown lines and an itchy rash
– PediculosisPediculosisInfestation with liceInfestation with lice
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PathologyPathology
Skin GrowthsSkin Growths– CallusCallus
Thickening of the skin caused by repeated rubbingThickening of the skin caused by repeated rubbingA A corncorn is a callus that has developed a hard core is a callus that has developed a hard core
– CicatrixCicatrixScar resulting from the healing of a woundScar resulting from the healing of a woundForms from granulation tissueForms from granulation tissue
– KeloidKeloidAbnormally raised or thickened scar that expands Abnormally raised or thickened scar that expands past the boundaries of the original incisionpast the boundaries of the original incision
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PathologyPathology
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PathologyPathology
Nevus (nevi)Nevus (nevi)– AKA moleAKA mole– Small, dark skin growths that Small, dark skin growths that
develop from melanocytesdevelop from melanocytes– Normally benignNormally benign– Dysplastic nevi are atypical moles that may Dysplastic nevi are atypical moles that may
develop into skin cancer develop into skin cancer
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PathologyPathology
Skin CancerSkin Cancer– Most common form of cancer, but often Most common form of cancer, but often
curablecurableBasal cell carcinomaBasal cell carcinoma
– Slow growing, rarely spreadsSlow growing, rarely spreads– Lesions are pink, smooth, Lesions are pink, smooth,
and raised with a depression and raised with a depression in the center (tend to bleedin the center (tend to bleed easily) easily)
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Squamous Cell Squamous Cell carcinomacarcinoma
Begins as a tumour Begins as a tumour of the squamous of the squamous epithelial cells that epithelial cells that can quickly spreadcan quickly spreadAppears as sores Appears as sores that will not heal or that will not heal or have a crusted, have a crusted, heaped-up lookheaped-up look
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PathologyPathology
– Malignant MelanomaMalignant MelanomaOccurs in the melanocytesOccurs in the melanocytes
Very dangerous and sometimes fatalVery dangerous and sometimes fatal
Signs:Signs:– A – AsymmetryA – Asymmetry– B – Border IrregularityB – Border Irregularity– C – ColourC – Colour– D – DiameterD – Diameter
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PathologyPathology
BurnsBurns– Injury caused by heat, flame, electricity, sun, Injury caused by heat, flame, electricity, sun,
chemicals, radiationchemicals, radiation– Described according to the percentage of total Described according to the percentage of total
body skin affected, as well as the depth body skin affected, as well as the depth (layers of skin involved)(layers of skin involved)
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PathologyPathology
– First Degree: First Degree: no blisters, superficial damage to epidermisno blisters, superficial damage to epidermis
– Second Degree: Second Degree: blisters, damage to epidermis and dermisblisters, damage to epidermis and dermis
– Third Degree: Third Degree: damage to epidermis, dermis, subcutaneous damage to epidermis, dermis, subcutaneous tissue, and possibly underlying muscletissue, and possibly underlying muscle
Varied tissue colour, no response to stimuliVaried tissue colour, no response to stimuli
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Diagnostic ProceduresDiagnostic Procedures
BiopsyBiopsy– Removal of a small piece of tissue for Removal of a small piece of tissue for
examination to confirm or establish a examination to confirm or establish a diagnosisdiagnosis
Incisional – not all of the tumour or lesion is Incisional – not all of the tumour or lesion is removedremoved
Excisional – entire tumor or lesion and a margin of Excisional – entire tumor or lesion and a margin of surrounding tissue are removedsurrounding tissue are removed
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TreatmentTreatment
MedicationsMedications– TopicalTopical
Affects only the area to which it is appliedAffects only the area to which it is applied
– TransdermalTransdermalApplied to unbroken skin to be absorbed Applied to unbroken skin to be absorbed continuouslycontinuously
Has a systemic effectHas a systemic effect
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TreatmentTreatment
Tissue RemovalTissue Removal– CauterizationCauterization
Destruction of tissue by burningDestruction of tissue by burning
– CurettageCurettageRemoval of material from the surface by scrapingRemoval of material from the surface by scraping
– DebridementDebridementRemoval of dirt, foreign objects, damaged tissue, Removal of dirt, foreign objects, damaged tissue, etc from a wound to prevent infection and promote etc from a wound to prevent infection and promote healinghealing
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TreatmentTreatment
– Incision and Drainage (I&D)Incision and Drainage (I&D)Cutting open a lesion and draining the contentsCutting open a lesion and draining the contents
– Moh’s surgeryMoh’s surgeryTechnique of excising skin tumours by removing Technique of excising skin tumours by removing tumour tissue layer-by-layer, examining the tissue, tumour tissue layer-by-layer, examining the tissue, and repeating until entire tumour is removedand repeating until entire tumour is removed