Differential Diagnoses of Common Presentations Flashcards
Brown Macule.
Inflammatory
Post-inflammatory
hyperpigmentation
Brown Macule. Drug/Toxin
UV radiation, actinic/solar
lentigo, freckle (ephelide)
Brown Macule. Miscellaneous (Congenital, Neoplasia, Other)
Congenital: café-au-lait spots, congenital nevus, epidermal/junctional
nevus
Neoplasia: lentigo maligna, MM, pigmented BCC
Other: melasma/chloasma (“mask of pregnancy”)
Discrete Red
Papule. Infectious
Folliculitis
Furuncle
Scabies
Discrete Red
Papule. Inflammatory
Acne vulgaris
Rosacea
Psoriasis
Urticaria
Discrete Red
Papule Drug/Toxin
Bites/stings
Discrete Red
Papule. Miscellaneous (Autoimmune, Vascular, Other)
Autoimmune: lichen planus; see Papulosquamous Diseases, D16
Vascular: hemangioma, pyogenic granuloma
Other: dermatofibroma, miliaria rubra
Red Scales. Infectious
Pityriasis rosea
Secondary syphilis
Tinea
Red Scales. Inflammatory
Dermatitis (atopic, contact,
nummular, seborrheic)
Discoid lupus
Psoriasis
Red Scales. Drug/Toxin
Gold
Red Scales. Miscellaneous (Autoimmune, Neoplastic)
Autoimmune: lichen planus; see Papulosquamous Diseases, D16
Neoplastic: mycosis fungoides
Vesicle. Infectious
Cat scratch disease Impetigo Viral: HSV, HZV, VZV, Molluscum, Coxsackie, Scabies
Vesicle. Inflammatory
Acute contact dermatitis
Dyshidrotic eczema
Vesicle. Drug/Toxin
none
Vesicle. Miscellaneous
Other: dermatitis herpetiformis, porphyria cutanea tarda
Bulla. Infectious
Bullous impetigo
Bulla Inflammatory
Acute dermatitis
EM, SLE, SJS/TEN
Bulla Drug/Toxin
Fixed drug eruption
SJS/TEN
Bulla Miscellaneous
Autoimmune: bullous pemphigoid, pemphigus vulgaris
Other: dermatitis herpetiformis, porphyria cutanea tarda
Pustule Infectious
Candida Dermatophyte Impetigo Sepsis Varicella
Pustule Inflammatory
Acne vulgaris Rosacea Dyshidrotic dermatitis Pustular folliculitis Pustular psoriasis Hidradenitis suppurativa
Pustule Drug/Toxin
Acute generalized
exanthematous pustulosis
(usually secondary to drug
reaction)
Oral Ulcer. Infectious
Aspergillosis CMV Coxsackie Cryptococcosis HSV/HZV HIV, TB, Syphilis
Oral Ulcer Inflammatory
Allergic stomatitis EM Lichen planus Seronegative arthropathies, SLE Recurrent aphthous stomatitis Behçet’s disease
Oral Ulcer Drug/Toxin
Chemotherapy
Radiation therapy
SJS/TEN
Oral Ulcer Miscellaneous.Autoimmune, Congenital,Hematologic, Neoplasia
Autoimmune: pemphigus vulgaris
Congenital: XXY
Hematologic: sickle cell disease
Neoplasia: BCC, SCC
Skin Ulcer Infectious
Plague
Syphilis
TB
Tularemia
Skin Ulcer Inflammatory
RA, SLE, vasculitis
UC (pyoderma gangrenosum)
Skin Ulcer Miscellaneous
Autoimmune: necrobiosis lipoidica diabeticorum (e.g. DM)
Congenital: XXY
Hematologic: sickle cell disease
Neoplasia: SCC
Vascular: arterial, neurotrophic, pressure, venous, aphthous, leukoplakia,
traumatic
