Dermatology Flashcards
(49 cards)
1
Q
Pemphigus Vulgaris
A
autoimmune of unclear etiology in which body becomes allergic to owen skin
- antibodies are produced against anigens in the intercellular spaces of epidermal cells
- bullae are within epidermis and are thin and fragile
- painful bullae but not pruritic
2
Q
Causes of Pemphigus Vulgaris
A
- Idiopathic
- ACE inhibitors
- Penicillamine
3
Q
Nikolsky’s sign
A
easy removal of skin by just a little pressure with the examiner’s finger pulling it off like a sheet
4
Q
Diseases where Nikolsky’s sign is present
A
- Pemphigus vulgaris
- Staphylococcus scalded skin syndrome
- Toxic epidermal necrolysis
5
Q
Pemphigus Vulgaris: Dx
A
skin biopsy
6
Q
Pemphigus Vulgaris: Tx
A
- use glucocorticoids, such as prednisone
- when steroids are ineffective, use the following:
azathiaprine
mycophenolate
cyclophosphamide
7
Q
Bullous pemphigoid
A
- can be drug induced by sulfa drugs and others
- fracture of skin is realtively deep and bullae are THICKER WALLED and LESS LIKELY TO RUPTURE
- oral lesions are rare
- less fluid loss and infection less likely
8
Q
Bullous pemphigoid: dx
A
- perform a biopsy with immunofluorescent antibodies
9
Q
Bullous pemphigoid: tx
A
- Use systemic steroids such as prednisone
- Alternatives to steroids
- tetracycline
- erythomycin with nicotinamide
10
Q
Pemphigus foliaceus
A
- associated with other autoimmune diseases
- can be drug induced from ACE inhibitors or NSAIDs
- bullae are more superficial than pemphigus vulgaris
- intact bullae rarely seen because they are so fragile
- no oral lesions
11
Q
Pemphigus foliaceus: dx and tx
A
- diagnosed by biopsy and treated with steroids Alternatives to steroids - mycophenolate - cyclophosphamide - azathioprine
12
Q
Porphyria Cutanea Tarda (PCT)
A
- disorder of porphyrin metabolism resulting in photosensitivity reaction to an abnormally high accumulaition of porphyrins
13
Q
Conditions associated with Porphyria Cutanea Tardia
A
- Alcholism
- Chronic hep C
- Liver disease
- Oral contraceptives
- Liver diease is associated with increased liver iron stores
- Diabetes are found in 25% of these patients
14
Q
Porphyria Cutanea Tarda: Clinical presentation
A
- Nonhealing blisters on sun exposed parts of the body such as backs of hands and the face
- Hyperpigmentation of the skin
- Hypertrichosis of the face
15
Q
Porphyria Cutanea Tarda: Diagnostic Testing
A
Test for urinary uroporphyrins
- uroporphyrins are elevated 2-5 times above coporyphyrins in this disease
16
Q
Porphyria Cutanea Tarda: Tx
A
- Stop drinking alcohol
- Stop all estrogen use
- Use barrier sun protection
- Use phlebotomy to remove Fe. Deferoxamine used to remove Fe
- Chloroquine increases the excretion of porphyrins
17
Q
Urticaria
A
- hypersensitive reaction, most often mediated by IgE and mast cell activation, which in EVANESCENT WHEALS AND HIVES
- localized with hypotension and hemodynamically instability
- onset within 30 minutes and last < 24 hrs
- itching is prominent
18
Q
Causes of urticaria
A
- Meds (aspirin, NSAIDS, morphine, codene, penicilline, phenytoin)
- Insect bites
- Foods (peanuts, shellfish, tomatoes, and strawberries)
- Emotions
- Contact with latex
19
Q
Chronic urticaria is associated with the following:
A
- Pressure on skin (e.g. dermatographism)
- Cold
- Vibration
20
Q
Severe acute urticaria: tx
A
H1 antihistamines (e.g. diphenhydramine, hydroxyzine, cyproheptatine
21
Q
Acute urticaria that is life threatening: tx
A
H1 antihistamines + systemic steroids
22
Q
Chronic urticaria tx
A
Newer antihistamines
- loratadine
- desloratadine
- fexofenadine
- certirizine
23
Q
If patient develops urticaria due to trigger that can’t be avoided, what’s long term solution?
A
Desensitization
** make sure to stop B-blockers because they inhibit the epinepherine
24
Q
Morbilliform rashes
A
- milder form of urticaria
- typical type of drug reaction
- rash RESEMBLES MEASURES; it is GENERALIZED MACULOPAPULAR ERUPTION THAT BLANCHES WITH PRESSURE
- can appear a few days after initial exposure
25
Morbilliform rashes: dx and tx
- Lymphocyte mediated
| - teat with antihistamines
26
Erythema Multiform Causes
```
- caused by:
penicillins
phenytoins
NSAIDS
Sulfa drus
Infection with Herpes Simplex or Mycoplasma
```
27
Erythema Multiforme
- presents with TARGETLIKE LESION that occurs on palms and soles
- lesions can be described as "irislike"
- bullae not unformly found
- does not involve mucous membranes
28
Erythema Multiforme: Tx
Antihistamines and treat the underlying infection
29
Stevens-Johnson Syndrome
- hypersensitivity rxn to meds (e.g. penicillins, sulfa drugs, NSAIDS, phenytoin, and phenobarbitol)
- usually involves 10 - 15 % of total body surface area
- has mucous membrane involvement
- respiratory tract involvement may be so severe as to require mechanical ventilation
- should be managed in burn unit
30
Mortality and morbidity associated with Stevens-Johnson Syndrome
- infection, dehydration, and malnutrition
31
Stevens-Johnson Syndrome: Tx
Supportive therapy
32
Toxic Epidermal Necrolysis
- most serious version of cutaneous hypersensitivt reaction
- covers 30 - 100% of body surface area
- sepsis is most common cause
- Nikolsky sign is present and skin easily sloughs off
33
Toxic Epidermal Necrolysis: Dx
Skin biopsy
| ** don't use steroids
34
Fixed Drug Reaction
- localized allergic drug reaction that occurs at precisely the same anatomic site with repeated drug exposure
- lesions are ROUND, SHARPLY DEMARCATD LESIONS THAT LEAVE HYPERPIGMENTED SPOT AT THE SITE
35
Fixed Drug Rxn: Tx
Topical steroids
36
Erythema Nodosum
- painful, red, raised nodules appear on anterior surface of extremities
- nodules are tender to palpation
- nodules do not ulcerate
- nodules last about 6 weeks
37
Erythema Nodosum associated with which conditions:
```
secondary to recent infections or inlammatory condtiions such as:
- Pregnancy
- Recent strep infxn
- Coccidiodomycoses
- Histoplasmosis
- Sarcoidosis
= Inflammatory bowel disease
- Syphilis
- Hepatitis
- Enteric infection (e.g. Yersinia)
```
38
Erythema Nodosum: Tx
- Analgesics and NSAIDS and treat the underlying disease
| - if symptomatic treatment fails, potassium iodide
39
```
Suspected fungal infxn : diagnostis
- tinea pedis
- tinea cruris
- tinea corporis
- tinea versiclor
- tinea capris
-
```
1. Perform KOHtest of skin. KOH can dissolve some epithelail cells and collage of the nail but doesn't melt away fungus
2. Most accurate test: culture of fungus
40
Onychomycosis (nail fungal infection) : tx
Oral terbinafine or itraconazole
- 6 weeks for fingernails
- 12 weeks for toes
41
Hair fungal infection (tinea capitus)
Oral terbinafine or itraconazole
42
Terbinafine
- used to treat skin and hair fungal infections
- potentially hepatotoxic
- check liver function tests periodically
43
Adverse effects of ketaconazole
- Hepatotoxicity
- Gynecomastia
* * don't use for onychomycosis**
44
Impetigo
- special bacterilal infection of skin limited to largely epidermis
- infection is described as "weeping" "oozing" "honey-colored" or draining"
- found in warm, humid conditions
- seen in poverty and in children
- can cause glomerulonephritis but no rheumatic fever
45
Impetigo: etilogy
Staphylococcus
| - can be caused by Streptococcus pyogenes (aka Group A Strep_)
46
Impetigo: Tx
- Any topical abx: mupirocin
| - If topical abx not effective, antistaphyloccocus oral abx
47
Erysipelas
- involves both dermis and epiderms
- most commonly caused by Group A Strep (pyogenes)
- most likely bacterial infxn to lead to fevers, chills, and bacteremia
- bright, red, angry, swollen appearance in face
48
Erysipelas: tx
= use systemic oral or IV abx
| - if there is culture confirmation of the organism as Streptococcus then penicillin G or ampicillin
49
Cellulitis
- bacterial infection of dermis and subcutaneous with Stap and Strep
