New drugs in the last days to weeks, immunization, infection, travel, contacts
Fever, pain, mucosal/ocular symptoms, pruritus, rapid progression
Immunosuppression, anticoagulation, animal/tick exposure, pregnancy
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← All presentations
Rash, Purpura & Dermatologic Emergencies
Rash is skin until it is sepsis, necrosis, mucosal disease, or anaphylaxis.
Your objective: explain the approach, recognize important warning signs, then test your recall.
Abbreviations explained
- ACS
- Acute coronary syndrome
- OMI
- Occlusion myocardial infarction
- ECG
- Electrocardiogram
- PE
- Pulmonary embolism
- POCUS
- Point-of-care ultrasound
- QTc
- QT interval corrected for heart rate
- LBBB
- Left bundle branch block
- RBBB
- Right bundle branch block
- hs-cTn
- High-sensitivity cardiac troponin
- CTA
- Computed tomography angiography
- ICU
- Intensive care unit
Filter
The jobRash is skin until it is sepsis, necrosis, mucosal disease, or anaphylaxis.
- Assess illness severity, vital signs, mucosa, eyes, palms/soles, and whether lesions blanch.
- Separate infectious/toxic, medication-related, ischemic/necrotizing, and allergic patterns.
- Photograph or mark progression when appropriate; reassess rather than trusting a single examination.
Most rashes are benign, but the dangerous minority declare themselves through toxicity, nonblanching purpura, pain out of proportion, mucosal involvement, skin failure, or rapid progression.
Meningococcemia / purpura fulminans Critical
Key: Toxic patient with nonblanching petechiae or purpura: resuscitate, cultures/antibiotics per sepsis protocol, and escalate.
Necrotizing soft-tissue infection Critical
Key: Pain out of proportion, rapid progression, bullae, anesthesia, or systemic toxicity; urgent surgical review.
SJS/TEN or severe drug reaction Critical
Key: Mucosal erosions, targetoid/blistering rash, skin pain, or detachment after a medication exposure.
Anaphylaxis / angioedema Critical
Key: Skin findings plus airway, breathing, circulation, or severe GI involvement is anaphylaxis.
Cellulitis, urticaria, viral exanthem Common
Key: Treat the patient and disposition according to systemic features and progression.
Tick what your patient has — the banner updates as you go.
Vitals and toxic appearance; blanching versus nonblanching
Mucosa, eyes, palms/soles, skin tenderness, bullae, crepitus
Mark margins of suspected cellulitis; full-body examination when concern is high
Immediate
- Sepsis workup and broad treatment when toxic or purpuric
- Surgical consultation first when necrotizing infection is plausible
Targeted
- CBC, renal/liver tests, coagulation, cultures when systemically unwell
- Biopsy/dermatology and ophthalmology input for suspected severe cutaneous adverse reaction
Avoid delay
- Do not use normal labs or imaging to rule out necrotizing infection when the examination is concerning
Medication safety reminder
Use this as a first-pass prompt; verify all medications, doses, concentrations, contraindications, weight, pregnancy status, and local protocols before administration.
Check indication, allergy, route, renal/hepatic risk, interactions, monitoring, and local formulary.
Discharge
- Clearly benign, stable rash with explicit return precautions and follow-up.
Admit / specialty review
- Extensive cellulitis, immunocompromise, diagnostic uncertainty, mucosal disease, or failed outpatient treatment.
Resuscitation / OR / burn-level care
- Sepsis/purpura, necrotizing infection, anaphylaxis, or extensive SJS/TEN.
Use objective reassessment and the local pathway.
Before the next decision · reassess and hand over
Use these learning prompts with the presentation’s pathway. They are not discharge criteria.
- Reassess: compare symptoms, observations and examination with the initial assessment and response to treatment.
- Warning signs for Rash, Purpura & Dermatologic Emergencies:
- Nonblanching purpura with fever or shock
- Painful, rapidly spreading, anesthetic, bullous, or necrotic skin
- Mucosal or ocular involvement
- Facial/tongue swelling, wheeze, hypotension
- New high-risk medication with skin pain or blistering
- Reconsider: check unresolved findings and alternative explanations, including the pitfalls below.
- Escalate: communicate deterioration, uncertainty or needs beyond the current setting.
- Plan the transition: identify outstanding results, responsibility for follow-up, patient understanding and specific return advice.
Clinical Pearls
- Nonblanching plus toxic is a sepsis emergency until proven otherwise.
- Skin pain is a higher-risk clue than itch.
Pitfalls
- Calling painful skin disease simple cellulitis without considering necrosis or drug reaction.
- Ignoring eye and mucosal examination in blistering disease.
PRACTICE REFRESHER
Rapid recall
Test your first action and the dangerous diagnoses before revealing the answer.
01 · First move
Before you scroll, what needs to happen first?
Assess illness severity, vital signs, mucosa, eyes, palms/soles, and whether lesions blanch.
02 · Immediate threats
Name at least two diagnoses that cannot wait.
Meningococcemia / purpura fulminans · Necrotizing soft-tissue infection · SJS/TEN or severe drug reaction
PRIVATE TO THIS DEVICE
Your learning note
Capture a weak point, a teaching pearl, or a question to take to your next shift.
Review schedule starts when marked reviewed
Foundational references below. No separate topic-specific guideline check is recorded here.
- Rosen’s Emergency Medicine, 10th ed. — dermatologic presentations
- IDSA skin/soft-tissue infection guidance; local burn/dermatology pathways