Tag Archives: derm

Erythema Multiforme

4 Dec

Submitted by Amit Kumar. 


*Acute immune mediated, distinctive target-like lesions

*Erythema multiforme “major”: EM with mucosal involvement (ocular, oral, genital)

*Population: Mostly 20-40yo, M > F

*Precipitators: #1 = infection (HSV most common, mycoplasma in children).

Other causes: medications, malignancy, autoimmune disease, immunizations, radiation, sarcoidosis, and menstruation

*Commonly confused with Stevens Johnson Syndrome (<10% body surface area) and Toxic Epidermal Necrolysis (>30% BSA): Also targetoid lesions with mucosal involvement, but mostly drug-induced

*Evaluation & diagnosis:

  • Skin punch biopsy (to check for HSV antigens in potential subclinical case, differentiate from autoimmune bullous diseases such as pemphigus or pemphigoid)
  • sampling of perioral lesions (for HSV PCR/Tzanck smear),
  • serologic tests for M. pneumoniae,
  • check labs (CBC, ESR, LFTs),
  • wound culture (if concerned for secondary infection)


  • Acyclovir 400mg q4h (if HSV), Prednisone 60mg daily followed by ~two week taper.
  • Symptomatic treatment: Benadryl, ELTA cream
  • Consult ophthalmology for ocular involvement
  • Monitor nutrition (if compromised due to oral involvement)
  • Pain control
  • Prophylaxis: Acyclovir 400mg BID (for HSV)


http://www.uptodate.com/contents/pathogenesis-clinical-features-and-diagnosis-of-erythema-multiforme?source=search_result&search=Erythema+multiforme&selectedTitle=1~150; picture 1, picture 2


visual aid: soft-tissue ultrasound

7 May

(apologies for the layoff between posts; busy time lately, but should be back into a rhythm)

some nice images via this April E-Med Journal article (for when you next need to determine if there’s something there to I & D):

Arrows (top to bottom) indicate: epidermis, subcutaneous tissue, muscle, bone


to help differentiate the sometimes difficult to distinguish (left to right): cellulitis, abscess, lymph node


References: emed journal article + pictures

Rash to Remember: Toxic Shock

11 Dec

A few pearls to help distinguish the badness of toxic shock syndrome from just any old rash

-involves skin and mucous membranes

-macular, resembles a sunburn

-involves the palms and soles

-more severe cases develop vesicles and bullae

-non-pitting edema due to increases in interstitial fluid

-late onset (1-3 weeks) develops into a pruritic maculopapular rash with desquamation of the palms and soles


Source: uptodate.com


Submitted by K. Estes

quick review of erythema multiforme

31 Jul

Rash that usually occurs in adults

appears within 72 hours of the offending agent or pathogen.

hypersensitivity that occurs as a result of exposure to several things including medications and infections most commonly but also malignancy and vascular disorders.

Hands and forearms are most commonly affected but it can involve all areas.

usually characterized by variously sized target lesions. Plus or minus enanthem (mucosal rash).

The most common causes are HSV, then mycoplasma infections.

Other common offenders are sulfonamides, penicillins, phenytoin, lupus, barbiturates, hepatitis, and lupus.

The pneumonic SOAPS may be used

  • Sulfonadmines,
  • Oral hypoglycemics,
  • Anticonvulsants/antibiotics,
  • Penicillin/phenytoin,
  • nSAIDS.

EM is on the spectrum with Stevens-Johnson and TEN, and has the least amount of epidermal detachment – none, versus SJS which has less than 10% and TEN having greater than 30% epidermal detacthment.

Patients may complain of burning or itching, fever, myalgias, arthralgias or malaise.

Treatment of localized disease involves short steroid burst and analgesics and antihistamines, while more advanced disease may benefit from inpatient admission to a burn unit.


Submitted by J. Stone.


References: (Tintinalli’s Emergency Medicine, Ch 245 Serious Generalized Skin Disorders.); picture

Skin Complaints in the Returning Traveler

11 Apr

Typically caused by:

-exacerbations of pre-existing disease (atopic dermatitis, psoriasis, etc.)

-environmental conditions (photosensitivity, contact allergies, etc.)

-infective organisms


Most rashes are minor problems such as sunburn and insect bites, and are self-limiting requiring only symptomatic care.


Top 10 tropical travel dermatoses requiring specific therapy:

-cutaneous larva migrans

-pyodermas (due to staph or strep)

-arthropod-reactive dermatoses

-myiasis (infection with a fly larva)

-tungiasis (infestation by burrowing flea)


-febrile syndromes with rash

-cutaneous leishmaniasis


-fungal infections


rash1Elevated, serpiginous, reddish-brown lesion of cutaneous larva migrans.
leishOld world cutaneous leishmaniasis ulcer.


Syndromes to be on the lookout for…

Fever and rash (petechial or hemorrhagic): dengue fever, arboviruses, rickettsial infections (e.g., scrub typhus), meningococcemia, leptospirosis, malaria, and erythema multiforme caused by drug reaction or common infection
Papules: insect bites, persistent lesions (chiggers), scabies, allergic drug reactions, cercarial dermatitis (swimmers), Pseudomonas folliculitis (hot-tubbing), onchocerciasis (long-term travel)
Nodules: furunculosis, myiasis (movement within the lesion), chancroid, syphilis, systemic parasites/fungi
Migratory: cutaneous larva migrans, strongyloidiasis (fast-moving and often on the buttocks), urticaria from various causes, and Loa loa (rarely)
Ulcerative: pyodermas, spider bites, chancroid and syphilis, cutaneous leishmaniasis



-rarely is it necessary to recommend anything more than symptomatic care in the ED

-referral to your local infectious disease or tropical medicine clinic for suspicious or chronic lesions


Submitted by K. Estes.

References: Tintinalli’s Emergency Medicine:  7th Edition; uptodate.com (pictures)

Evil tuna? – the cautionary tale of Scombroid

4 Feb


-Commonly occurs after ingestion of fish from the Scombridae family (tuna, mackerel)

-Other fish associated with this type of food poisoning include mahi-mahi, herring, blue fish, sardines

When fish is stored in improper temperatures, bacteria metabolize histidine into histamine



                -Can occur 30 minutes up to 24 hours after ingestion

                –Flushing, headache, abdominal cramping, diarrhea, and vomiting

                -Symptoms usually last 6-8 hours



                –Antihistamines (H1 and H2 blockers)


Submitted by Joey Grover.


Sources: Tintinalli’s Emergency Medicine:  7th Edition; Rosen’s Emergency Medicine:  7th Edition; picture

Postherpetic Pseudohernia: you can’t diagnose it if you’ve never heard of it…

18 Dec


a limited protrusion of the abdominal wall, without structural defect

Causes include:

  • diabetic radiculoneuropathy,
  • Lyme disease,
  • polymyositis,
  • reactivation herpes zoster.


Classically, reactivation herpes zoster infection affects sensory nerve roots

however, it may extend to motor involvement, which can include paresis of diaphragmatic, upper and lower limb, or abdominal musculature.


Natural History:pseudohernia1

Symptoms of abdominal wall pseudohernia typically occur within 2 weeks of the rash and typically include an abdominal bulge in the region of the affected dermatome.

Typically, patients have a good prognosis, with resolution of symptoms within 18 months


Submitted by K. Sullivan.


References: Postherpetic Pseudohernia, Annals of Emergency Medicine July 2012