Dermatology - 5% Flashcards
Acanthosis Nigricans
Velvety thickening
Hereditary, DM, obesity, Drugs (nicotinic acids), Gi/GU malignancy
Gray-brow, black thickend plaques
Acne Vulgaris
Acneiform Eruptions
Open comedones (blackheads) vs closed comedones (whiteheads)
Pilosebaceous unit, hyperkeratinization of follicle
Sxs
- comedones, papules, pustules
- nodules, cysts
Tx
- water based products, milk and stress
- Step wise
- topical retinoid -retin-a
- Benzoyl peroxide
- topical antibiotics (clinda, azithro,
- PO Abx - Minoxycine, tetracyclines - doxycycline, can cause photosensitivity)
- Isoretinoin - preg test q 4 wk
- OCPs
Rosacea
Acneiform Eruption
W, 30-50yo facial pilosebaceous unit
Sxs
- facial erythema, telangiectasias, papules, rhinophyma
- triggered by heat, etoh, spicy foods
Tx
- Redness - Topical Metronidazole, azelaic acid, topical ivermectin
- Prim papules/pustules - PO abx - tetracycline - doxy, minocyxline - failed topical
- Telangiectasia/Rhino - derm consult
Actinic Keratosis
Long, repetitve sun exposure; 60% of SCC from AK
Sxs
- single, or multp lesions
- red papules/plaques in coarse adherent scales
- feel like sandpaper
Tx
- Prevention
- Cryo
- Topical fluoroucacil/Efudex)
- Topical Imiquimod/Aldara
- bx
Alopecia
Tinea capitis - 2/2 fungal infection
- tx with selenium sulfide or ketoconazole shampoo
Alopecia Areata
- oval shaped well demarcated hair loss, exclamation point hair
- autoimmune - attack hair follicles
- no tx - hair regrowth but not native hair
Telogen effluvium
- scalp disorder - thinning or shedding hair d/t hair into telogen phase
- after psychologically stressful event
- self limiting
Androgenic alopecia
- male pattern baldness; autosomal dominant
- topical minoxidil
- PO finasteride
Atopic Dermatitis aka Eczema
Chronic relapsing skin disorder
Type I IgE hypersensitivity reaction
a/w Allergic triad
- Asthma
- Allergic Rhinitis
- Atopic dermatitis
Sxs:
- Pruritic rash
- Dry, scaly skin - lichenification, fissures, worsening rash
- usu flexor surfaces for adults (neck, eyelids, forehead, face, wrists)
- facial & extensor surfaces for children (elbows, behind knees)
Tx:
- Moisturizers, and emollients - Cetaphil or Eucerin
- Topical CS for flare ups
- Topical Calcineurin inhibitors - mod to sev dz
- Tacrolimus and Pimecrolimus
- UV photo therapy for refractory
Bullous Pemphigold
Vesiculobullous Dz
Rare, acq’d autoimmune subepidermal blistering skin disorder = autoantibodies (IgG) against hemidesmosomes
Sxs:
- Large bullae and crust on axillae, thighs and abd
- more tense, less fragile, deeper than pemphigus vulgaris
- Negative Nikolsky skin (bleeding when scratched)
Dx:
- skin bx - direct immunofluorescence exam
- deposits of IgG and C3 basement membrane
Tx:
- Self limited
- Systemic CS - high doses until remission
- Azathioprine? - immunosuppressive agents
Burns - Degrees and Rule of 9s
Rule of 9s (pic)
1st degree - sunburn
- erythema involved tissue
- skin blanches w/ pressure
- skin may be tender
2nd degree - partial thickness
- skin is red and blistered
- skin very tender
3rd degree - full thickness
- burned skin is tough and leathery
- skin non-tender
4th degree - Into bones and muscles
Burns - minor/major, tx
Minor
- < 10TBSA adults
- < 5 TBSA young/old
- <2% full thickness
- not involve face, hands, perineum, feet, cross major joints or be circumferential
Major
- > 25% TBSA adults
- >20% TBSA young/old
- >10% full thickness burn
- Burns w/ face, hands, perineum, feet, cross major joints/circumferential
Tx:
- monitor ABCs, fluid repletion, topic abx
- cleans w/ mild soap and water, no direct ice
- Irrigate chemical burns w/ running water x 20 ms
- topic abx for superficial burns
- fingers and toes wrapped individually to prevent maceration and gauze placed btwn them
Candidiasis
Moisture, warmth, breaks in barrier
intial papules
beefy red eroded patches w/ satelitte regions
Tx - nystatin, azole cream
PO flucanozole
Cellulitis
Acute bacterial skin infection from portal entry
MCC - GA Strep or S. aureus; animal bites via P. multicida or human bites E. corrodens
Sxs:
- Pain, warmth, swelling
- Spreading erythema (mark w/ pen) - non blanching
- flat margins and not well demarcated
Dx:
- would culture f/u in 48 hrs
Tx:
- Mild cellulitis - MSSA
- Cephalexin or Dicloxacillin
- Cat bite - Augmentin or doxy if PCN allergic
- Puncture wound - Cipro
- MRSA
- Bactrim 1 DS tab PO BID
- Clindamycin 300-450 mg PO
- Doxycyclin 100 mg PO BID
Contact Dermatitis
Irritant Dermatitis
Chemic irritant - topic steroids - sharply demarc erythema, edema, oozing, crusting
Contact Dermatitis
Allergic Contact Dermatitis - reexposure to allergic substance 10-14 sensitization
MC - urushiol resin (poison ivy), neomycin, nickel
Pruritic, well demarcated erythema
Topic CS
Contact Dermatitis: Allergic vs Irritant
Allergic Contact Dermatitis - MCC poison ivy (Rhus dermatitis)
- delayed Type IV hypersensitivity reaction
- 10-14 days
- re-exposure appears w.in 12-48 hrs
Irritant Contact Dermatitis - MCC chemical Irritants or diaper rash
- Cleaners, solvents, detergents, urine, feces
Sxs:
- Acute - well demarcated erythema and exudative lesions
- Burning, itching, erythema
- Eczematous eruptions
- Chronic - plaque and scaling - lichenification
Dx - patch gesting
Tx:
- Localized - mid or high potency CS
- Triamcinolone 0.1% or Clobetazol 0.05%
- >20% BSA - systemic CS
- Prednisolone 0.5-1mg/kg/d
- should resolve w/in 12–24 hrs
Dermatophytes - Tinea
Fungus
Tinea corporis, pedis, cruris
Trichomycosis - hair and hair follicles
Onychomycosis - nails
Sxs
- Annular patches w/ peripheral scaling - active on periphery w/ central clearning
Dx
- KOH microscopy
Tx
- Micanozole, clotrimazole
- Terbinafine - fungicidal
- PO Terbinafine if extensive involvement
Drug Eruptions
adversed cutaneous reaction to admin of a drug; usu w/in past 6 wks
Sxs:
- skin reactions are MC
- can be mild to severe (multiorgan damage)
- Pruritus, mild fever => systemic sxs fever, malaise, HA
Dx
- clinical - bacterial, viral or underlying skin dz (cutaneous lymphoma)
Tx
- withdraw offending agents
- monitor for sxs of CV collapse - anaphylaxis, DRESS, SJS/TEN, extensive bullous rx, generalized erythroderma
- Don’t rechallenge w/ drugs causing urticaria, bullae, angioedema, DRESS, anaphylaxis
- anaphylaxis or widespread uritcaria => epinephrine 0.2-0.5mg & prednisone to prevent recurrence
- Antihistamines
Drug Eruptions
Exanthematous
MC of all skin eruptions
Typically 7-10 days after starting drugs, MC abx (amoxicillin)
Sxs
- Morbilliform (measles like) on trunk and spread to extremities, pruritic
Tx
- Topical Steroids
- PO antihistamines
- dc abx
Drug Eruptions
Fixed
Sxs
- Single, few, dusky red, violaceous
- occurs in the same place each time med taken, occurs more quickly each time
- 30-8 hrs; end of extremities
- MCC - tetracyclines, metronidazole, NSAID, salicylate
Tx
- DC med
- topical CS
- antimicrobial ointment
Eczema
Chronic superficial inflammation of skin
Atopic Dermatitis
exposed to irritative factor - allergic triad (eczema, allergy, asthma), doesn’t hold water well
Sxs
- pruritis, chronic, dry erythematous skin w/ papules
- scaling skin eruptions
- vesicles, crusting
- Infancy - extensor (back of elbow), front of knees, scale face
- childhood - flexor surfaces
- adult - flexors hands/foot
Tx
- Emollients*** - vaseline
- Steroids - affected areas lowest strength
Erysipelas
Form of Cellulitis = MC d/t Group A Strep (pyogenes)
Sxs:
- Usu face or LE
- Pain, warmth
- Superficial, well demarcated erythema
- fever, chills
- +/- bullae
Dx - culture
Tx:
- mild - Pencillin G (or erythromycin/clinda if PCN allergic)
- Mod - bactrim or PCN/Cephalexin
- Severe - IV Vanco
Erythema Infectiosum (Fifth Disease)
Viral Exanthems
Parvovirus B19 - “Slapped cheek” rash on face
Sxs:
- Low grade fever
- sore throat
- bright rash on cheeks -> spreads to trunk, arms, & legs
- maculopapular w/ central clearing
- lacy reticular rash
Dx: clinical
Tx: Rash lasts a few days to several weeks
pruritic rash
symptomatic tx
Erythema Multiforme
Acute, self limited skin rx - Type IV hypersensitivity rx
a/w HSV**, sulfa drugs, oral mucosal lesion uncommon
Sxs
- extremities - hands, feet, mucosa
- Target like shape, raised, blanching
- NOT itchy
Dx
- Major - widespread skin lesions & 2 mucosal sites
- Minor - limited skin region and 1 type of mucosal (oral)
- Negative Nikolsky sign
- Target lesions, concentric zomes - dusky center
Tx
- PO antihistamines, tylenol, cool compresses
- EM major - CS, opthal consult
- EM minor - supportive care
- Acyclovir - if recurrent
Hand Foot Mouth Disease
Viral Exanthems
Coxsackie type A virus
Children < 10 yo; very contagious in 1st week - spread via direct contact w/ saliva and mucus
Herpangina Is blister located to just the mouth
Sxs:
- Small, tender, erythematous papules or vesicles on pharynx, mouth, hands, feet
- Punched out, cratered
- Irritability
- Loss of appetite
- General irritability
- Feeling unwell
Dx - clinical
Tx
- clears up in 10 days
- pain meds for sxs relieve
- Good hand hygiene
Herpes Zoster
Varicella (chickenpox) - reactivation causing maculopapular rash along one dermatome
Dx - Tzanck Smear - multinucleated giant cells
Zoster Opthalmicus
- shingles w/ CN V - dendritic lesions on slit lamp
Zoster Oticus (Ramsay-Hunt Syndrome)
- facial n CN 7, otalgia
- lesion on ears, auditory canal and TM
- facial palsy auditory symptoms
- ddx Bell’s palsy
Tx:
- Acyclovir, valacyclovir, famciclovir - given w/in 72 hrs to prevent post-herpetic neuralgia
- Post herpetic Neuralgia pain > 3 mos- parethesias or decreased sensation
Hidradenitis Suppurativa
Genetic, env factor (DM, PCOS, Obestiy)
sxs
- Inflammed, v painful nodules
- sinus tract, scarring, from repeated
- Double comedones*** pathogno
Tx
- derm
- Topical or PO abx
- TNF
- Surgery
Impetigo
Highly contagious bacterial skin infx - MCC S aureus, S pyogenes or both
Children or adults
Begins as papules -> vesicles -> ruptured to form thick, adherent, golden crust
Sxs:
- Red sores form around nose and mouth
- Yellow-brown/golden crust
- Non-painful and pruritic = honey colored and weeping
Dx - Gram stain and culture
Tx:
- Topical Mupirocin, dicloxacillin or cephalexin for more severe illness
- MRSA - Doxy, Clinda or Bactrim
- Abx x 7 d
Lice
Sxs:
- pruritic scalp, body (corporis), or groin (pubis)
- Small white specs on hair shafts
Dx:
- observation of nits and lice - nits are ovoid, grayish white eggs
Tx:
- Permetherin topical 1% - shampoo and cream
- Launder fomites aka sheets in > 131 F or 55C
- Seal toys in bag for 72 hrs
- PO Ivermectin for resistant cases
Lichen Planus
Papulosquamous Disorders
Inflammatory dermatosis unkn eti
Sxs - 5 Ps
- Pruritic
- purplish
- polygonal
- plain topped papules
- Flexor surface of extremities
- Wickham’s striae - white lines on plaques
- Koebner phenomenon is common
Tx -
- topical steroids, UV therapy, retinoids
- antihistamines (hydroxyzine)
- long lasting lesions = Hep C testing
- Oral LP - risk of Oral SCC
Measles (Rubeola)
Paramyxovirus via respiratory droplets
Sxs:
- 10-12 days incubation
- Prodrome
- 1-3 d; 3 C’s
- Cough, Coryza, Conjunctivitis
- 1-3 d; 3 C’s
- Enanthem
- 4 8 hrs before Exanthem
- Koplik’s spots - red/white/blue spots In mouth
- Exanthem
- 4 days after fever onset
- Morbilliform - maculopapular, blanching rash
- Cephalocaudal - head to extremities spread
Dx: Clinical, Measles IgM abs
Tx:
- supportive, anti-inflammatories, isolate 1 wk after rash onset
Melasma
Hyperfunctional melanocytes - usu in pregnant or on OCP; worse with sun exposure
Macular, splotchy, hyperpigmentated in sun exposure
Tx
Sunscreen, SPF >30
epidermal melasma - hydroquinone, tretinoin
Basal Cell Carinoma
Neoplasms
Basal cell cancer - new skin as old one dies; younger ind 2-40yo
RF - heavy sun exposure
Sxs
- White waxy lump, translucent
- raised pearly and rolled borders, telangiectasis
- central ulcer on sun exposed areas - hand and neck
Dx
- Shave or punch biopsy
Tx
- Surgery w/ margins - Moh’s sx
- limited potential for mets
- Fluorouracil or imiquimod to affected areas
Kaposi Sarcoma
Neoplasms
HHV-8; AIDS defining cancer; angioproliferative disorder
Sxs
- nt swts, wt loss
- multiple, well demarcated red/purple firm nodules and plaques on head, neck, and mouth
- ulcerate and bleed
Dx - biopsy
Tx
- Cryotherapy, excision,
- radiation tx
- HAART**
Melanoma
Neoplasms
Cancer of melanocytes (skin pigment); UVB/UVA; young women
Superficial spreading is MC type of melanoma
Sxs
- ABCDE
- Asymmetry
- Border - irregular
- Color
- Diameter - increasing or > 5mm
- E elevation/raised
Dx - excisional biopsy - with margins
Tx
- Excision and wide margins
- Depth of lesion
- Clarks anatomical depth
- Breslow’s total depth
- Stage I-III = surgical excision is curative
- Stage IV = chemo
- avoid sunburns, SPF30
Squamous Cell Carcinoma
Neoplasms
2nd MCC, Epidermal keratinocytes;
UV or chemical exposure
Sxs
- erythematous, indurated scaly/ulcerated papules
- skin exposed on elerly
- faster growing thatn BCC
- can become tender or painful
Dx - biopsy - carcinoma until proven otherwise
Tx - surgical excision +/- Mohs
- good prognosis w/ immediate tx
Onychomycosis
Fungal infection of toes and fingernails
Yellow, thickened nails
Dx - fungal culture, wet mount of KOH
Tx - PO Antifungal
- Terbinafine 250 mg/d PO x 12 wks for toenails
- Itraconazole pulse x1 wk on and 3 wks off vs continuous
Paronychia
MCC S aureus; superficial inflammation of lateral and posterior fold of skin around nails
Tx
- I&D of abscess
- warm compresses
- abx - PO cephalexin (MRSA coverage)
- topical not effective
Pemphigus Vulgaris
Vesiculobullous Dz
Potentially fatal - autoimmune blistering dz; MC Mediterranean or Jewish descent 40-60 yo
Sxs
- painful mucocutaneous lesions
- Nikolsky sign - sloughing of skin w/ pressure
- non-healing ulcers for at least 1 mo, extremely painful
- fragile blisters mouth to elsewhere
Dx
- Immunofluorescence - intercellular deposition of IgG or C3
- Biospy - acantholysis
Tx
- PO Prednisone
- Immunosuppressive agent (azathioprine, or methotrexate)
- Dapsone, gold, cyclophosphamide for refractory
Pilonidal Disease
abn skin growth at tailbone/natal cleft that contain hair and skin
MC teens/20s, Males, Obese, sedentary, local trauma
eti - sinus tract, abscess
Sxs:
- pain, discomfort
- swelling above anus or near tailbone
- drainage of pus and blood
Dx - clinical
Tx:
- I&D with wound debridement - look for sinus tract
- Abx to prevent cellulitis
- Cefazolin + metronidazole
- Augmentin
Pityriasis Rosea
Papulosquamous Disorders
Older teens and young adults; can follow URI
Sxs
- Herald patch - salmon red, ONE plaque
- oval scaly lesions line up against folds (Langer lines)
- Christmas tree distribution
Tx
- self limiting - 3-8 wks
- anti-pruritics
- RPR ro syphilis
Pressure Sores
Sacrum and hip most often affected; resposition every 2 hrs
Stage 1 - erythema of localized area, usu non-blanching over bony surfaces
- Aggressive preventative measures, thin-film dressings for protection
Stage 2 - partial loss of dermal layer, resulting in pink ulceration
- Occlusive dressing to maintain healing
- transparent films, hydrocolloids
Stage 3 - full dermal loss often exposing subcutaneous tissues and fat
Stage 4 - full thickness ulceration exposing bone, tendon, or muscle. Osteomyelitis might be present
- debridement of necrotic tissue
- Exudative ulcers - will benefit from absorptive dressings - calcium alginates, foams, hydrofibers
- Dry Ulcers - occlusive dressing to maintain moisture, hydrocolloids, hydrogels
Psoriasis
Papulosquamous Disorders
Psoriasis Vulgaris MC; skin and joint hyperproliferation; 20s and 50s (bimodal)
Sxs
- Pruritic, well demarcated, erythematous plaques
- silvery scaling
- EXTENSOR - elbows and knees
- Auspitz’s sign - bleed when scale is picked
- Koebner’s phenomenon - minor trauma cause new lesions
Dx - clinical
Tx
- emollients
- phototherapy
- severe - methotrexate or immunologics
Roseola (6th Disease)
Caused by HHV 6 and 7
Between 6mos-2yo
Sxs:
- Sudden high fever (102-104)
- Red rash appears as fever subsides
- blanching maculopapular rash - neck/trunk -> face -> extremities
- rash lasts for 1-2 days
Dx - clinical
Tx - bed rest, fluids, antipyretics
Rubella (German’s Measles)
Rubella virus - spreads through sneezing/coughing
Contagious 1-2 wks before sxs
Teratogenic in 1st Trimester
Sxs:
- Erythematous, discrete maculopapular exanthem
- First on face, spreads to trunk and extremities; generalized w/in 24 hrs spares palms and soles**
- lasts for 3 days
- Fever
- Lymphadenopathy
Dx -
- EIA
- Serological assays
- Rubella specific IgM abs remain + for > 1 year.
Scabies
Skin infestation by mite - Sarcoptes scabiei
Sxs:
- Pruritic papules - S shaped or linear burrows on skin
- MC web spaces in intertriginous regions - hands, wrists, finger webs
- Severe itching, @ night
Dx:
- clinical
- definitive Skin scrape - microscopic observation of mite, egg or feces
Tx
- Topical Permetherin 5%, wash off 8-14 hrs, repeat 1 week
- Wash all bedding/clothes
-
PO Ivermectin 200 mcg/kg PO once, then repeat In 2 wks
- C/I in pregnant/breast feeding
Seborrheic Dermatitis
Sebaceous gland are most active; MC in newborns 2-12 mos
D/t Malassezia yeast
Sxs:
- Infants - thick, white, yellow greasy scale on scalp aka cradle cap
- Adults - flaky, greasy, erythematous patches on scalp found behind ears - body folds
Tx:
- Ketoconazole 2% shampoo - baby
- Antifungal shampoo - Selenium sulfide - selsun blue
Seborrheic Keratosis
MC benign cutaneous; genetic, later in life
Sxs
- Sharply, demarcated “greasy”, waxy, “stuck on”
- verrucous or papillomatous growth
- face, neck or trunk, no palm or soles
Tx
- no tx req’d
- cryosx, curettage, or flat excision
Steven Johnson Syndrom / Toxic Epidermal Necrolysis
Extensive necrosis and detachment of epidermis and mucosal surfaces ;
SJS <10% of BSA; TEN - older pts and > 30% of BSA
Uus occurs 8 wks after drug exposure
Eti:
- Sulfa
- Anticonvulsants (Phenytoin or carbamazepine)
- Tetracyclines
- Allopurinol or
- Abx - bactrim, B-lactam, FQs, penicillin**
- NSAIDs
Sxs
- Fever, HA, rhinitis + myalgias preced lesions by 1-3 days
- Rash rapidly extends to rest of body
- Flaccid blisters spreads and break with pressure
- + Nikolsky’s sign – lateral pressure
Tx
- EMERGENCY - stop offending drugs
- BURN UNIT
- IV fluids
- pain control
- systemic steroids
- OPTHAL
*
Spider Bite - Black Widow
Red hourglass on Abdomen
Sxs:
-
Neurologic manifestations - toxic rx,
- nausea, vomiting,
- HA
- fever
- syncope
- convulsions
Tx
- wound care, symptomatic tx
- treat with anti-venom in elderly and kids
- Benzos, opioid
Spider Bite - Brown recluse
Brown Violin on Abd
- Necrotic wound - local tissue reaction
- local burning at site for 3-4 hrs
- blanched area - d/t vasoconstriction
- Central Necrosis erythematous margins around Ischemic center “red halo”
- 24-7 hrs after hemorrhagic bullae w/ Eschar formation
- Necrosis “blue” center
Sxs:
- Pain
- Erythema
- ecchymosis
- ulceration and necrosis
Tx:
- wound care, delayed excision
- Abx erythro, cepholosporin
- Tetanus prophy
Tinea Versicolor
Superficial yeast infx - Malessezia furfur, humid lipid rich env
Round oval, sharply marginated scaling macules
trunk and chest
Dx - KOH, woods-lamp blue green fluores
Tx - selenium sulfide or ketoconazole shampoo or lotion
Urticaria
skin rash triggered by rx to certain foods, medications, stress or other irritants
Eti - Infection, Insect/Infestations (younger)
Ingestion, Inhalation, Injection (older)
Sxs:
- Blanchable, pruritic, raised, red or skin colored papules, wheels or plaques
- disappears within 24 hrs
- + Darier’s sign - localized urticaria appearing where skin Is rubbed (histamine release)
- Angioedema - painless, deeper form of urticaria affecting lips, tongue, eyelids hands and genital
Dx - clinical
Tx:
- Self limited
- Antihistamine meds
- 2nd gen antihistamine H1 blockers - 1st line
- Allegra, claritin, Zyrtec
- 1st gen AHs - sleep disturbances
- Hydroxyzine/diphenhydramine
- H2 AHs - as adjuvants
- Cimetidine, ranitidine
- Steroids for exacerbations, avoid chronic use
- 2nd gen antihistamine H1 blockers - 1st line
- IF anaphylaxis - epinephrine 0.3 to 0.5mg IM route
*
Vitiligo
Autoimmune rx against melanocytes; precipitating factor - stress, illness, trauma, severe sunburn
Sxs - chalky pigment, will not fluorescence (ddx tinea versicolor)
Tx
- sunscreen
- cosmetic cover up
- repig - topical glucocorticoid
- skin graft
