Pediatric emergency medicine trisk 456

TABLE 88.1
RASHES COMPOSED OF MACULES AND PAPULES: ETIOLOGIC
CLASSIFICATION


Infectious
Viral
Roseola infantum
Rubeola
Rubella
Erythema infectiosum (fifth disease)
Varicella (early manifestations before bullae)
Epstein–Barr virus (10–15% of cases have macular or maculopapular rash)
Molluscum contagiosum (papules)
Dengue
“Nonspecific” viral
Enterovirus
Echovirus
Coxsackievirus
Adenovirus
Bacterial
Scarlet fever
Syphilis
Disseminated gonorrhea
Fungal
Pityriasis versicolor
Other infections
Rocky Mountain spotted fever
Ehrlichiosis
Mycoplasma (15% of cases)
Etiology uncertain but thought to be viral

Pityriasis rosea
Kawasaki disease
Papular acrodermatitis
Noninfectious
Bites and infestations
Insect bites
Scabies
Miscellaneous
Drug reaction


Allergic contact dermatitis
Irritant contact dermatitis
Papular urticaria
Erythema multiforme
Guttate psoriasis
Pityriasis lichenoides
Lichen nitidus

EVALUATION AND DECISION
In approaching a child with an exanthem, a careful history and full examination
of all cutaneous surfaces will often be all that is required to make a diagnosis. The
most important historical features include the duration of the rash (acute or
chronic), initial distribution, extent of spread (generalized or localized), ill
contacts (including sexual partners), and any associated systemic symptoms,
including fever. The physical examination should include a careful systematic
inspection of all mucocutaneous surfaces, with special attention paid to
involvement of the oropharynx, palms and soles, extensor or flexor surfaces,
scalp, and trunk.
TABLE 88.2

POTENTIALLY LIFE-THREATENING ILLNESSES ASSOCIATED
WITH DIFFUSE MORBILLIFORM ERUPTION
Rocky Mountain spotted fever
Kawasaki disease
Erythema multiforme
Dengue fever
Rubeola
Ehrlichiosis
Drug reaction with eosinophilia and systemic symptoms (DRESS)


TABLE 88.3
GENERALIZED RASHES THAT OFTEN HAVE CHARACTERISTIC
CLINICAL APPEARANCES
Rubeola
Erythema infectiosum (fifth disease)
Hand–foot–mouth disease (coxsackievirus A16)
Molluscum contagiosum
Scarlet fever
Pityriasis versicolor
Pityriasis rosea
Roseola infantum
Insect bites
Erythema multiforme
Stevens–Johnson syndrome
Drug reaction with eosinophilia and systemic symptoms
For patients with widespread rash who appear ill, consider drug
hypersensitivity reaction, or severe viral or bacterial infection. Figure 88.12 may
help with an approach to morbilliform/mixed macular and papular eruptions.
For patients who do not appear ill, certain exanthems will have distinctive

patterns that make the diagnosis readily apparent. Erythema multiforme, rubella,
coxsackievirus infections ( Fig. 88.14 ), erythema infectiosum ( Fig. 88.15A,B ),
scarlet fever, varicella, MC ( Fig. 88.16 ), tinea versicolor ( Fig. 88.17 ), pityriasis
rosea ( Fig. 88.18 ), and roseola all have recognizable clinical appearances. Many
of these illnesses have characteristic distributions or associated signs and
symptoms that aid in their diagnoses. If the pattern of the rash does not evoke
immediate recognition from the examiner, a more methodical approach is
indicated, as outlined in Figure 88.19 .