Diffuse maculopapular rash
- Viral exanthem: measles, rubella (German measles), erythema infectiosum ("slapped-cheek" disease), exanthem subitum (roseola), primary HIV infection, infectious mononucleosis, dengue
- Other infection: typhoid fever, secondary syphilis, Lyme disease, leptospirosis, rat-bite fever, relapsing fever, ehrlichiosis, epidemic typhus, endemic typhus, scrub typhus, erythema marginatum (rheumatic fever)
- Noninfectious: drug rash (with drug fever or unrelated infection), systemic lupus erythematosus, adult Still’s disease
Peripheral eruption
- Meningococcemia or gonococcemia
- Secondary syphilis
- Rocky Mountain spotted fever
- Erythema multiforme
- Bacterial endocarditis
- Hand, foot, and mouth disease
Desquamative erythema
- Toxic shock syndrome (staphylococcal or streptococcal)
- Scarlet fever
- Kawasaki disease
- Staphylococcal scalded skin syndrome
- Exfoliative erythroderma syndrome (eg, underlying psoriasis, eczema, drug eruption)
- Erythema multiforme major or toxic epidermal necrolysis
Vesicles or bullae
- Varicella (chickenpox)
- Staphylococcal scalded skin syndrome
- Erythema multiforme major or toxic epidermal necrolysis
- Hand, foot, and mouth disease
- Rickettsialpox
- Ecthyma gangrenosum (neutropenic, pseudomonal)
- Disseminated Vibrio vulnificus (cirrhosis, seafood or seawater exposure)
Purpura or petechiae
- Bacterial endocarditis
- Meningococcemia or gonococcemia
- Rocky Mountain spotted fever
- Purpura fulminans (severe disseminated intravascular coagulation)
- Thrombotic thrombocytopenic purpura
- Other: epidemic typhus, rat-bite fever, enteroviral petechial rash, viral hemorrhagic fever
Other
- Urticarial vasculitis (serum sickness, connective tissue disease, infection, idiopathic)
- Nodules due to disseminated infection (eg, fungal), erythema nodosum, Sweet’s syndrome (acute febrile neutrophilic dermatosis)
- Pustular psoriasis