Derm disorders Flashcards
Principles of derm assessment
- is the pt otherwise well without systemic signs or other symptoms? likely condition limited to the skin
- is the pt miserable but not systemically ill? often uncomfortable with itch, burning, or pain (scabies, herpies zoster
- Systemically ill with constitutional s/s (fever, fatigue, loss of appetite, unintended weight loss, malaise)? dermatologic manifestation of systemic disease (varicella, transepidermal necrosis, lyme disease, SLE)
- Consider wich pts are at greatest risk for the condition
- consider transmission/contagion risk
- are there primary lesions only or primary and secondary lesions
Primary Vs. Secondary skin lesion
- Primary: results from a disease process, has not been altered by outside manipulation, treatment or natural course of disease (vesicle)
- Secondary: lesions altered by outside manipulation, treatment, natural course of disease (crust)
Papule
single uniformly brown colored, slighty raised, irregularly shapped with defined borders
6mm in diameter
Macule
single non-palpable area of discoloration, irregularly shapped
5mm or less in diameter
Purpura
flat, non-blanchable, confluent, purple-colored irregularly-shaped lesions on skin ranging 2-20mm
caused by low plts
clustered
occuring in a group without a pattern
vessiccular lesion seen in HSV1
Scattered
generalized over body without a specific pattern or distribution
viral exanthem - rash triggered by virus (rubella)
confluent/coalescent
multiple lesions blending together
plaques seen in severe psoriasis
annular
in a ring
characteristic bulls eye lesion with central clearing as in lyme disease
Actininc Keratosis
- precancerous lesion: likely only 1:100 progress to SCC
- predominanatly found on sun-exposed skin
- microscopic to several cm
- stuck on apperance - red, brown or flesh tone, often tender but usually minimally symptomatic
- lesions can remain unchanged, spontaneously resolve, or progress to invasive SCC
- Bx not needed for Dx.
- Intervention: topical 5FU, imiqumimod cream, dicolfenac gel, phododynamic therapy, cryosurgery
Basal cell Vs Squmous cell carcinoma
BCC
* sun exposed areas
* de novo - new lesion
* papule, nodule without central erosion
* pearly or waxy apperance, relatively distinct borders with or without telangiectasia
* metistatic risk low
SCC
* Sun exposed areas
* can arise from actininc keratoses or de novo
* red, conical hard lesions with or without ulceration (appears more angry)
* less distinct borders
* metastatic risk greater (3-7%) greates risk with lesion on lip, oral cavity, or genetalia
Metastatic melanoma
ABCDEE
Assymetric
Borders Irregular
Color not uniform
Diameter usually greater than 6mm
Evolving new lesion or change in longstanding lesion
Elevated
Psoriasis Vulgaris tx
medium potency topical coticosteroid
Scabies treatment
permethrin lotion
Verruca vulgaris tx
Imiquimod cream - immune modulator
Tinea pedis tx.
topical ketoconazole
Rosacea tx
topical metronidazole
Phytodermatitis tx
Topical
* mild or high potency topical corticosteroid- triamcinolone, clobestasol
* areas of thinner skin - lower potency corticosteroid - consider oral
systemic tx
* preferred when >20% total body surface is affected, or severe rash, or is rash impacts face, genitals, hands, or rash impacts occupational function.
* prednisone 0.5 - 1 mg/kg/day for 5-7 days then half dose for additional 5-7 days.
Impetigo - nonbullous
erythematous macule that rapidly evolves into vesicle or pustule, ruptures, contents dry, leaving a crusted, honey colored exudate
staphlococcus aureus, streptococcus pyogenes (gram+)
treat with topical mupirocin
Impetigo bolus
bulla contain clear yellow fluid that turns cloudy, dark yellow. Bullae rupture easily within 1-3 days, leaving a rim of scale around red, moist base, followed by a brown - lacquered or scalded skin appearance.
usually requires systemic abx
Cellulitis
infection of dermis and subcutaneous fat usually includes heat, redness, and discomfort
caused by streptococcus pyogenes or less commonly staphylococcus aureas (MSSA is beta-lactamese producer, MRSA resistance via altered binding sites)
TX for mild cases
* PO penicillin VK (suseptible to beta-lactamase)
* PO cephalexin (preferred)
* PO dicloxacin
* PO clindamycin (risk of c. diff)
Abcess tx
Mild
* I &D
* Warm Compress
Moderate
* I &D, C&S
* TMP/SMX (bactrim) or doxycycline
* Change intherapy based on C&s results:
- MRSA continue above
- MSSA dicloxacin or cephalexin
