Morbilliform / drug-like
Widespread red spots or bumps, often trunk-predominant, after medication or viral illness.
- Derm is more reasonable with fever, facial edema, eosinophilia, mucosa, or organ injury.
- Usually not inpatient Derm when mild, stable, and without red flags.
Blistering / erosive
Blisters, raw skin, peeling, mucosal erosions, painful dusky patches, or unclear autoimmune blistering disease.
- Derm may change biopsy technique, wound care, and disposition.
- Ophtho or burn/ICU may be concurrent for eyes or extensive detachment.
Purpuric / necrotic / retiform
Non-blanching purple spots, net-like violaceous rash, necrosis, livedo, painful ulcers, or rapidly worsening lesions.
- Derm may help separate vasculitis, vasculopathy, infection, embolic disease, and mimics.
- ICU, ID, surgery, Rheum, nephrology, or heme may be first or concurrent.
Vesicular / pustular / punched-out
Grouped vesicles, pustules, punched-out erosions, disseminated lesions, eschars, or infection-like morphology.
- Think eczema herpeticum, disseminated HSV/VZV, mpox-like eruption, deep fungal disease, or atypical infection.
- Derm may change biopsy/culture site, testing, isolation, or disposition.
Erythroderma / severe scaling
Most of the body is red or scaly, with admission-level skin burden, swelling, warmth loss, pain, or pruritus.
- Derm may change biopsy, topical regimen, wet wraps, systemic therapy discussion, or CTCL evaluation.
- Stable chronic eczema or psoriasis without systemic instability is different.
Autoimmune / systemic pattern
Skin findings that point toward systemic disease: dermatomyositis, lupus-like, vasculitic, neutrophilic, or ulcerative patterns.
- Derm is more useful when biopsy changes Rheum, oncology, ID, or immunosuppression decisions.
- State weakness, dysphagia, dyspnea, arthritis, renal/GI symptoms, and infection concerns.
Malignancy / paraneoplastic concern
Rapidly changing or nonhealing lesion, erythroderma with lymphadenopathy, CTCL concern, dermatomyositis signs, or severe unexplained pruritus.
- Derm may change biopsy site and systemic workup direction.
- Routine stable skin cancer screening is usually outpatient.
Common stable rash
Stable eczema, psoriasis, seb derm, acne, rosacea, tinea, intertrigo, uncomplicated urticaria, mild exanthem, routine mole check, or uncomplicated cellulitis/abscess.
- Usually not inpatient Derm without hard stops or disposition-changing diagnostic uncertainty.
- Escalate if pain, mucosa, blistering, necrosis, systemic illness, immunocompromise, or rapid progression appears.