4 - Serious Stuff Flashcards
What is a “drug eruption”?
A derm thing caused by drugs
Rash
Pruritus
Could be basically any patient sensitive to any compound in any drug
Describe the morphology of drug eruption:
Maculopapular is the MC presentation
Could also be urticarial
Or just skin flushing with pruritus
Basically, could be anything
What is the MC type of drug eruption?
Exanthems (maculopapular)
May be indistinguishable from viral exanthem
Goes away rapidly when you stop taking the drug
Usually spares the face
What is the MC site of a fixed drug eruption?
The glans penis
But can occur anywhere
Describe a fixed drug eruption
Single or multiple, round, sharply demarcated, dusky red plaques
Appear soon after drug exposure
At the same site every time
Often blister
How do we treat drug eruption?
Stop the med (duh)
Give antihistamines
PO or topical class III-IV steroids
Be alert for development of anaphylaxis
How will a patient with urticaria appear?
Itchy
Uncomfortable
Possibly short of breath, difficulty swallowing, or itchy mouth/throat (ominous signs)
Morphology of urticaria?
Hives (wheal)
Firm, edematous plaque
Faint pink with central pallor
Orange peel appearance (2/2 follicular accentuation)
Transient (about 24hrs) then fade and recur
What is the etiology of urticaria?
Release of histamine from mast cells
Immediate hypersensitivity reaction
Causes of physical urticaria?
Dermatographism
Pressure (belts, constrictive jewelry)
Solar
Cold/heat
Aquagenic
Cholinergic (exercise, emotion)
Usually only lasts 30-60 mins
Acute vs chronic urticaria - what’s the cutoff?
6 weeks
Txt of acute urticaria
IM or PO diphenhydramine
PO steroids
If anaphylaxis - epinephrine SQ (1:1000)
Txt for chronic urticaria:
Antihistamine, 2nd gen (i.e. cetirizine)
H2 blockers (i.e. ranitidine)
PO steroids (short-term)
Restrictive diet
What is angioedema?
Localized, dramatic and rapid swelling of the subcutaneous tissue
Burning and painful swelling
Can happen anywhere - commonly the lips, eyes, tongue, trunk, genitalia, hands
Can involve the GI and respiratory tracts
MAY LEAD TO ANAPHYLAXIS
Txt of angioedema
Potentially aggressive management (if severe anaphylaxis develops)(have epi ready, if rapid swelling of resp tract may need to intubate before that shit closes up)
IM or PO diphenhydramine
PO steroids
What is the MC small vessel necrotizing vasculitis?
Leukocytoclastic (hypersensitivity) vasculitis
Describe Leukocytoclastic (hypersensitivity) vasculitis
Prodrome of fever, malaise, myalgia, arthralgia
Lesions itch and are painful
Appear in crops, last 1-4 weeks
Can spread to multiple organs besides skin
Morphology of Leukocytoclastic (hypersensitivity) vasculitis
Inflammation of blood vessel walls cause leakage of RBC’s
Vesicles and points of necrosis
Starts small and continues to increase in size, may coalesce
Palpable purpura
Heals with scars and hyperpigmentation
Distribution of Leukocytoclastic (hypersensitivity) vasculitis
Any dependent area (due to increased hydrostatic pressure and extravasation of RBC’s
Lower legs, arms, back and sacrum if bed-bound
Etiology of Leukocytoclastic (hypersensitivity) vasculitis
Immune-complex deposition on vessel walls, inflammatory response damages walls
Underlying cause could be: viral hepatitis, strep, UTI, drugs, systemic dz, malignancy…soooo again, anything…starting to see a pattern with derm: anything is anything
How do we manage Leukocytoclastic (hypersensitivity) vasculitis
Look for a cause
Also, look for systemic involvement (renal, GI, etc)
Txt the underlying condition
Topical steroids / abx cream
50% of Leukocytoclastic (hypersensitivity) vasculitis patients will have:
Hematuria
What is Henoch-Schonlein Purpura?
An acute Leukocytoclastic (hypersensitivity) vasculitis that occurs mainly in kids (2-10 yrs)
MC systemic vasculitis in kids
Palpable purpura on the legs and buttocks
Athralgias, abdominal pain
Labs for HSP?
Nothing specific - ESR, serum complement, and IgA are all up
Morphology of HSP
Palpable purpura on legs and butt
Trunk or normally spared
Starts as hives, then class Leukocytoclastic lesions within 48 hrs
2-10mm in diameter and appear in crops among coalescent ecchymosis and pinpoint petechiae
Fade in several days leaving brown macules
What causes HSP?
It’s a hypersensitivity reaction
May be preceded by an URI by 1-3 weeks
Strep with IgA deposits around the vessels
How do we manage HSP?
It’s a self-limiting dz
Watch for GI bleed and blood loss
NSAIDs and PO steroids
Occasionally dapsone or plasmapheresis
Long-term prognosis for HSP directly dependent on:
The severity of renal involvement
What’s the common patient profile for erythema multiforme?
Young adults (age 20-40)
Fever, malaise, burning lesions
Preceding URI or HSV infx (or mycoplasma pneumoniae)
Morphology of erythema multiforme?
Urticarial papules
Target lesion or vesicles/bullae (red macule with central color change, coalesce to involve large areas, recur in crops for 2-3 weeks)
Distribution of EM
Back of hands
Palms
Soles
Extensor limbs
May be generalized
Mucous membranes in up to 70% of cases
Etiology of EM?
Preceding URI or HSV
Immune complex dz - damages vasculature, causes tissue necrosis
Management of EM:
Symptomatic relief, otherwise no tx if mild
Prednisone with taper or 1-3 weeks
If HSV-induced, oral antivirals
What’s the patient profile for SJS?
Very sick and in pain
Any age, but more common in young children and young adults
Preceded by URI with high fever and malaise
OR induced by meds for seizure, gout, abx
Morphology of SJS:
Initial - fever, stinging eyes, pain with swallowing - 1-3 days prior to cutaneous sxs
Flat, atypical targets or pruritic macules, widespread on the trunk first, then neck, face, and proximal upper extremities
Palms/soles early - maybe
Bullous lesions
Ulcerative lesions with hemorrhagic crusts appear on the mucosal surfaces
Etiology of SJS:
Direct toxic effect from seizure drugs
Viral URI
Mycoplasma pneumonia
Management of SJS:
Steroids controversial
Control itching and pain
IV fluids (really important)
If severe -> burn unit
Ophthalmology consult
ABX if secondary infx
NG feed if severe throat pain
Foley if severe dysuria
Complications of SJS:
Sloughing of upper and lower respiratory tract
Blindness 2/2 corneal lesions
Toxic epidermal necrolysis - presentation
Looks like SJS initially but the big difference is that TEN then progresses to the skin peeling off at the dermoepidermal junction
Any age
Prodrome - fever (MC), HA, sore throat (associated URI)
Sudden onset red, tender skin
High mortality
Morphology of TEN:
Generalized red macular “sunburn” look
Diffuse, hot erythema
Within hours, skin is painful
Skin peels of (Nikolsky sign)(bad sign)
Desquamation
Vesicles and large bullae appear
Scalp is spared
Mucous membrane involvement in TEN:
Inflammation, blistering, erosion of mucosal surfaces
Especially the oropharynx
GI tract usually spared
Vaginal tract epithelium blisters and erodes
Eyes - purulent conjunctivitis, ulceration, erosion
MCC of TEN:
ABX
Followed by anticonvulsants, NSAIDs
Management of TEN:
Burn unit ASAP
NO STEROIDS
Cyclosporine A
Cyclophosphamide
Plasma exchange
IVIG
What is the MCC of death in the setting of TEN?
Infection (hence the need for burn unit care - they are Jedi’s with avoiding infection)
What is staphylococcus scaled skin syndrome? (SSSS)
A blistering disease caused by s. aureus exfoliative toxins
Who gets SSSS?
Newborns (Ritter’s dz), infants, small children
Staph infection with negative skin culture
Common sites for positive cultures: ears, tonsils, sinuses, conjunctiva
Morphology of SSSS:
Generalized sunburn-like erythema, sandpaper-like rash
Very tender (unlike scarlet fever)
Clown facies - crusting around mouth
Exfoliation
Total body distribution
Etiology of SSSS:
2/2 coag (+) s. aureus toxin
Same organism as bullous impetigo
The kid’s immature kidney’s can’t clear toxin effectively
Management of SSSS:
Low mortality
Anti-staph meds (diclox/ceph)
No corticosteroids (interfere’s with host immunity)
Avoid touching skin
How to differentiate TEN from SSSS
Do a frozen section
Split is SSSS is more superficial than in TEN
Mucocutaneous lymph node syndrome is AKA:
Kawasaki’s
Patient profile for Kawasaki’s
2 or 3 year-old, previously healthy, fever 101-104 (unresponsive to antipyretics)
Cervical adenopathy
Rash
Oral/mucous membrane changes
Morphology of Kawasaki’s
Acute phase - fever 7-14 days and resolves. Conjunctival injection, strawberry tongue, tender edema of palms/soles (peels after 10 days), diffuse maculopapular rash
Subacute phase - end of fever to 25 days -> desquamation of fingers, toes, arthralgias, thrombocytosis
Convalescent phase - begins when clinical signs disappear through normalization of ESR (about 7 weeks after onset)
Distribution of Kawasaki’s:
Conjunctival injection
Strawberry tongue
Palms/soles -> red, swollen, tender
Diffuse urticaria and maculopapular eruption (desquamation in 5-7 days)
Diaper dermatitis is common
Cervical lymphadenopathy
Etiology of Kawasaki?
We don’t know.
Management of Kawasaki’s
Watch for cardiac abnormalities
High-dose IVIG
ASA
Labs in Kawasaki’s?
WBC can be over 20K
Elevated ESR/CRP
Thrombocytosis
What’s the patient profile for toxic shock syndrome (TSS)?
Post-partum Post-C-section Nasal packing and nasal staph carriage Diaphragm use Post-op (most cases) 1970’s super awesome mega-absorbent tampons
What’s the morphology of TSS?
Diffuse, scarlet fever-like rash
Macular, erythematous, looks like a sunburn
Desquamation of palms/soles
Vaginal hyperemia and tenderness
Conjunctival injection
Strawberry tongue
Diagnostic criteria for TSS:
Fever > 102
Diffuse, erythematous, macular rash
Mucous membrane involvement
HOTN (SBP<90mmHg)
Multi-system involvement
What causes TSS:
Coag (+) staph toxin
Localized infection with systemic toxin spread
How do we manage TSS?
Beta-lactamase-resistant abx (oxacillin, nafcillin, cefoxitin, vancomycin/clindamycin)
I and D abscess
Remove tampon
Increased hydration
Maintain BP with pressors if necessary
Mortality 5-10% (higher in dudes)
Dont use regular tampons
Because now there is new all natural Cherokee hair tampons.
