Dermatologic Emergencies


  • Appearance: diffuse maculopapular, edematous plaques
  • Symptoms: known trigger, transient, pruritic
  • Management: remove trigger, epinephrine, glucagon


  • EM
    • Causes: drugs, HSV
    • Appearance: target lesions, symmetric, palm/sole involvement
    • Management: remove offending agent, supportive care
  • SJS (<10% TBSA)
    • Cause: drugs
    • Appearance: >2 mucous membranes
    • Findings: +Nikolsky
    • Symptoms: flu-like
    • Management: burn center, dermatology consult
  • TEN (>30% TBSA)
    • Management: IVIG, steroids, burn center, dermatology consult


  • Epidemiology: <6yo, older if immunosuppressed
  • Appearance: painful, diffuse erythema, bullae, no MM involvement
    • Stage 1: tender erythroderma
    • Stage 2: exfoliation
    • Stage 3: desquamation
  • Findings: +Nikolsky
  • Management: antibiotics (cephalosporin), no steroids

Rash Mnemonics

Palmar Rash

  • “sifting rocks scabbed Emma’s palms”
  • Syphilis (2°)
  • RMSF
  • Scabies
  • EM

Nikolsky Sign

  • SSSS
  • PV


  • RMSF
  • Meningococcemia
  • DIC
  • Endocarditis


  • Epidemiology: <20yo, dorm, military barracks
  • Appearance: diffuse petechiae, palpable purpura
  • Management: antibiotics, steroids

Necrotizing fasciitis

  • Symptoms: POOP, rapid progression
  • Appearance: bullae, crepitus, systemic toxicity
  • Management: surgery, antibiotics


  • Symptoms: flu-like
  • History: tick bite, camping/hiking
  • Appearance: wrist/ankle spreading inward (centrifugal), petechiae
  • Diagnosis: clinical, titers
  • Management: doxycycline (increased mortality if not treated)


  • Epidemiology: 40-60yo
  • Pathophysiology: autoantibodies (desmoglein), causes superficial epidermal separation (pemphigus for superficial)
  • Symptoms: painful oral blisters, small bullae
  • Findings: +Nikolsky
  • Management: steroids (methylprednisolone 1g IV), burn center


  • Epidemiology: >70yo
  • Pathophysiology: autoantibodies, deeper dermal layer (pemphigoid for deep)
  • Symptoms: not painful, no oral lesions
  • Findings: large, tense, unruptured bullae
  • Management: steroids

Ultrasound Gallery



Non-compressible tubular structure in the RLQ of a patient with focal abdominal tenderness. >6mm in diameter.

Common Bile Duct

Common Bile Duct

A tubular structure typically anterior to the portal vein without flow. Normally measures <4mm, increases by 1mm per decade after 40yrs.



"Cobblestone" appearance of soft tissue suggesting infection/edema.

Fetal Heart Rate

Fetal Heart Rate

Placing the M-Mode marker over the most visibly active portion of the fetal heart allows for measurement of the fetal heart rate.

Free Fluid

Free Fluid

Free fluid in the hepatorenal recess.



Severe hydronephrosis.

Thoracic Aorta Aneurysm

Thoracic Aorta Aneurysm

Subxiphoid view of thoracic aorta, markedly dilated (>3cm) with thrombus.

Pericardial Effusion

Pericardial Effusion

Mild pericardial effusion in a patient with pleuritic chest pain.

Inferior Vena Cava

Inferior Vena Cava

IVC without significant respiratory variation.



B-lines extending deep from pleura suggestive of interstitial fluid accumulation (pulmonary edema).

"Shred" sign

"Shred" sign

Irregular, "shredded" pleural line suggestive of consolidation.



Transition point with loss of lung sliding in a patient with a small spontaneous pneumothorax.

Lower Extremity Edema


51 year-old male with a history of HTN, DM and chronic alcohol abuse presenting with lower extremity swelling. He notes one month of progressive, bilateral lower extremity swelling, in the past two weeks associated with increasing pain and redness and is now no longer able to ambulate due to pain. He denies fevers/chills, chest pain or shortness of breath. He also denies orthopnea and paroxysmal nocturnal dyspnea. He states that he has not had these symptoms prior to one month ago. On review of systems he denies nausea/vomiting, abdominal pain, and changes in bowel or urinary habits. He has a history of GI bleeding (unknown treatment) but denies hematemesis, hematochezia or melena. He has previously experienced alcohol withdrawal, which manifested as tremors, but no hallucinations or seizures.


  • HTN
  • DM
  • Chronic EtOH abuse






  • Drinks 1-2 pints of alcohol daily, last drink this morning.
  • Denies current tobacco or drug abuse, no prior IVDA.





Physical Exam:

VS: T 37.6 HR 86 RR 16 BP 128/84 O2 99% RA
Gen: Adult, non-obese male, lying in bed. Tremors noted in upper extremities.
HEENT: PERRL, EOMI, no scleral icterus. Mucous membranes moist.
CV: RRR, normal S1/S2, no additional heart sounds, JVP 3cm above sternal angle at 30°.
Lungs: CTAB, no crackles.
Abd: Soft, non-distended, with normoactive bowel sounds. Liver edge palpated 1cm below costal margin at mid-clavicular line, non-tender. No rebound/guarding.
Ext: Warm, well-perfused with 2+ distal pulses (PT, DP). 3+ pitting edema symmetric in bilateral lower extremities to knee. Erythema and warmth bilaterally extending from ankles to mid-shin. Mild tenderness to palpation. No pain with passive dorsiflexion. 3x3cm shallow ulceration below medial malleolus on right lower extremity without underlying fluctuance or expression of purulent material. No venous varicosities noted. Decreased sensation to light touch below knee bilaterally.
Rectal: Normal rectal tone, brown stool, guaiac negative.
Neuro: Alert and oriented, CN II-XII intact, gait intact, normal FTN/RAM.


  • CBC: 7.4/13.1/39/180
  • Creatinine: 0.84
  • Albumin: 4.3
  • BNP: 28


Venous Lower Extremity Ultrasound

  1. No DVT.
  2. Pulsatile flow in bilateral EIV (external iliac veins) suggestive of elevated right heart pressure.


51M with HTN, DM, EtOH abuse presenting with lower extremity edema. Chronic bilateral lower extremity edema likely secondary to chronic venous insufficiency perhaps related to OSA given ultrasound findings of pulsatile flow in EIV’s. Doubt systemic cause: no evidence of heart failure on exam and normal BNP, no stigmata of cirrhosis and normal albumin, normal creatinine. Also, no evidence of DVT on ultrasound though bilateral DVT unlikely. Bilateral cellulitis also unlikely as the patient is afebrile without leukocytosis, however the patient was started on antibiotics including ceftriaxone and TMP/SMX given erythema, warmth and tenderness to palpation. The patient received benzodiazepines which eased withdrawal symptoms and he was admitted for continued treatment.

Mechanisms of Lower Extremity Edema: 1

Mechanisms of Lower Extremity Edema

Differential Diagnosis of Lower Extremity Edema: 1,2

Differential Diagnosis of Lower Extremity Edema


History 1,2

  • Duration: acute (<72h) vs. chronic
  • Pain: DVT, CRPS, less severe in venous insufficiency
  • Systemic Disease
    • Cardiac: orthopnea, PND
    • Renal: proteinuria
    • Hepatic: jaundice, ascites
  • Malignancy: lymphedema
  • Improvement with elevation/recumbency: venous insufficiency
  • OSA: snoring, daytime somnolence
  • Medications: B-blocker, CCB, hormones, NSAID’s

Physical Exam 1,2

  • Distribution: unilateral, bilateral, generalized
  • Quality: pitting, non-pitting
  • TTP: DVT, cellulitis
  • Varicose veins: venous insufficiency
  • Kaposi-Stemmer: inability to pinch dorsum of foot at base of 2nd toe (lymphedema)
  • Systemic Disease
    • Cardiac: JVD, crackles
    • Hepatic: ascites, scleral icterus, spider angiomas
  • Brawny, medial maleolar involvement: venous insufficiency

Key Features Distinguishing Cellulitis: 3

  • Typically unilateral and acute
  • Often with systemic symptoms (fever, leukocytosis)
  • Risk Factors: immunosuppression, previous episodes, DM, PVD


  1. Trayes, K. P., Studdiford, J. S., Pickle, S., & Tully, A. S. (2013). Edema: diagnosis and management. American family physician, 88(2), 102–110.
  2. Ely, J. W., Osheroff, J. A., Chambliss, M. L., & Ebell, M. H. (2006). Approach to leg edema of unclear etiology. Journal of the American Board of Family Medicine : JABFM, 19(2), 148–160.
  3. Keller, E. C., Tomecki, K. J., & Alraies, M. C. (2012). Distinguishing cellulitis from its mimics. Cleveland Clinic journal of medicine, 79(8), 547–552. doi:10.3949/ccjm.79a.11121
  4. WikEM: Pedal edema