Presentation on theme: "Chapter 46 Disorders of Skin Integrity and Function"— Presentation transcript:
1 Chapter 46 Disorders of Skin Integrity and Function
2 Skin Infections Superficial fungal infections Ringworm, athlete’s foot Attack the keratinized (dead) cellsInflammatory reaction to toxins causes most signs and symptomsDeep fungal infectionsCandidiasis, sporotrichosisAttack living tissueMay attack other organs
3 Bacterial Skin Infections ImpetigoMay lead to post- streptococcal hypersensitivity reactionsThese can cause glomerulonephritis
4 Viral Skin Infections Verrucae (warts) Benign neoplasms (papillomas) Herpes simplex (cold sores)Herpes zoster (shingles)Herpes invades dorsal root gangliaCaused when chickenpox herpesvirus is reactivatedTravels out nerve to skin and causes a new inflammation
5 Question Which of the following microbes cause warts? Fungus Virus BacteriaAny of the above may cause warts.
6 AnswerVirusWarts are caused by viruses; they’re benign neoplasms (abnormal tissue growths).
7 Scenario Mrs. K is worried about her complexion… She says she always had good skin, but now her face itches and burns on the right side, and there are red lumps on one side of her foreheadQuestionWhat are the possible causes?
8 Acne Disorder of sebaceous glands Related to: Hormonal stimulation of sebaceous glandsIncreased number of sebaceous cellsIncreased sebum productionInflammatory response to bacteria in sebum
9 Allergic and Hypersensitivity Dermatoses Type I allergiesAtopic eczemaUrticaria (hives)
10 Type I Allergies Type I allergies are mediated by IgE Discussion What cells must be involved in this process?On the first exposure to the allergen?On repeated exposure?When the allergen binds to IgE?What inflammatory mediators are involved? How?
11 QuestionWhich chemical mediator is released by mast cells as part of the inflammatory response?HistamineLeukotrieneCytokineAll of the above
12 AnswerHistamineHistamine (stored in mast cells) is one of the first substances to be released during the inflammatory response. Histamine release results in bronchoconstriction, mucosal edema, and increased mucus production.
13 Autoimmune UrticariaIn autoimmune urticaria, the client creates anti-IgE antibodiesDiscussionHow would this cause hives?How would a deficiency in complement inhibitor cause hives?Why would antihistamines help?Why would corticosteroids help?
14 Drug-Induced Skin Eruptions Erythema multiformeOccurs after herpes simplex; self-limitingStevens-Johnson syndromeSkin detaches from body surface; <10% of body affectedToxic epidermal necrolysis>30% of epidermis detaches30%–35% mortality rate
16 Psoriasis Activated T cells growth attract factors neutrophils and monocyteskeratinocytesenterand bloodthevessels growpapulescreatecreatepapulesinflammation
17 Burns First-degree: outer layers of epidermis Second-degree: epidermis and dermisPartial-thickness: only part of dermisFull-thickness: entire dermisThird-degree full-thicknessExtends into subcutaneous tissueMay damage muscle, bone, blood vessels
18 Scenario Mr. D was boiling water and the pot tipped over on him… He has painful, bright pink, blistering burns over most of his left arm and chestQuestionHow would you categorize this burn?
19 Scenario (cont.) His pulses are weak Bowel sounds are absent Mr. D's burns are pink but the rest of his body looks pale, and he has a rapid heart rate…His pulses are weakBowel sounds are absentRespiration is rapidQuestionWhat has caused these signs?
20 Complications of Burns Burn shockRespiratory system dysfunctionHypermetabolic responseRenal insufficiencyGastric ulcerationSepsisConstriction of areas under circumferential burnsSystemic infection
21 ScenarioA woman was severely burned and she has been in the hospital for eight daysQuestionWhy would she be developing:Increased urine production?Weight loss?Increased temperature?GI bleeding?
22 QuestionTreatment for third-degree burn patients includes all but which of the following?Fluid replacementRemoval of dead tissue/escharAntibioticsAloe
23 AnswerAloePatients suffering from third-degree (full thickness) burns lose fluid through the skin and are prone to infection. They must receive fluid replacement and antibiotics to fight or prevent infection. Dead tissue (eschar) must be removed daily (debridement) in order to prevent infection. Because third-degree burns destroy the epidermis, the application of topical aloe would serve no purpose.
26 Sun Exposure Sun exposure increases the risk of skin cancer Cumulative sun exposure increases risk of:Basal cell carcinomaSquamous cell carcinomaSevere sun exposure with blistering increases risk of:Malignant melanoma
27 Malignant Melanoma Cancers arising from melanocytes Asymmetry Border irregularityColor variegationDiameter >0.6 cmEvolving change over time
29 Types of Melanomas 70% are superficial spreading Raised edges; grow horizontally and verticallyUlcerate and bleed15%–30% are nodularDome-shaped, blue-black4%–10% are lentigo malignaSlow growing, flat2%–4% acral lentiginousOn palms, soles, nail beds, mucous membranes
30 QuestionWhich type of skin cancer is associated with the worst prognosis?Basal cellSquamous cellMalignant melanomaEpendymal cell
31 Answer Malignant melanoma Malignant melanoma begins in the melanocytes, and possesses all of the characteristic features associated with cancer (asymmetry, irregular border, many colors, and a diameter >0.6 cm) as defined by the American Cancer Society.Basal cell cancer has the best prognosis, and squamous cell cancer has a good prognosis as long as it is detected early.