Most ED chief complaints involving skin lesions are due to infections,
irritants, and allergies.1 Fortunately, few presentations
represent life- or limb-threatening skin disorders. Visual diagnosis
with the use of pattern recognition is the key to diagnosis. The
recommended approach for the diagnosis of a skin disorder in the
ED (assuming resuscitation or stabilization is not required) is
1. Determine the chief complaint.
2. Obtain a brief history (duration, rate of progression, and location
3. Perform the dermatologic examination (morphology and distribution).
4. Formulate the differential diagnosis based on lesion morphology
5. Elicit additional concerns from the history (associated complaints, comorbidity,
medications, or exposures) and include or exclude syndromes in the
differential diagnosis based on this information.
6. Perform ancillary investigations, if necessary.
7. Obtain dermatologic consultation, if necessary, and arrange for appropriate
referral (primary care or dermatologic).
Determine the chief complaint and obtain a brief history (discomfort,
duration, rate of progression, and location of lesions). The secondary
history should include issues relating to the lesion: morphology,
evolutionary nature, rate of progression, and distribution. Associated
systemic complaints and mucosal systems must be identified. Ask
about exposures to medications (over-the-counter, prescription,
and illicit), immunizations, toxins, chemicals, foods, animals,
insects, plants, and ill contacts. Sexual history, if appropriate,
and medical and family histories should be reviewed. Asking about
medication use, sun exposure, or particular food ingestion also
may yield helpful information.
The patient should be gowned and in a room with adequate lighting.
Inspect all skin and mucosal surfaces, including hair, nails, scalp,
and mucous membranes. Then evaluate the specific skin lesions. A
magnifying lens and a portable light are helpful aids.
Examine the skin systematically. Determine the distribution,
pattern, arrangement, morphology, extent, and evolutionary changes of
the lesions. Distribution is the location of the
skin findings, and the pattern is their anatomic,
functional, and physiologic arrangement. For example, a unilateral
band-like arrangement of lesions on the thorax suggests varicella-zoster
virus infection. Skin diseases often present with a predilection
for certain body areas; the distribution of lesions will assist
in narrowing the diagnostic possibilities. From the anatomic perspective,
the skin surfaces that are usually considered as separate areas
of distribution are generalized body; face and scalp; trunk and
axillae; groin and skin folds; and hands, feet, and nails. The extremities
may be further subdivided into upper versus lower, proximal versus
distal, wrists versus ankles, and hands versus feet (Figure
Allergic contact dermatitis. A. Allergic
contact dermatitis from exposure to poison ivy. Erythema, vesiculation,
and bullae are present on the fingers and the dorsal surfaces of
the hands. Note the linear streak across the right hand. This finding ...