Nonspecific Viral Exanthem

The vast majority of viral exanthems in children are nonspecific and lack a distinctive prodrome, lesion morphology, enanthem, or distribution.
The exanthem often presents abruptly as a widespread, generalized, asymptomatic eruption.

Numerous viruses have been associated with nonspecific viral exanthems, most commonly enteroviruses, adenovirus, parainfluenza virus, respiratory syncytial virus, and influenza virus.

A prodrome or concurrently associated features may include low-grade fever, myalgias, headache, rhinorrhea, or gastrointestinal symptoms.
In children the prodrome may be mild or subclinical and the exanthem is the most prominent feature, which brings the child to medical attention.
The eruption usually begins abruptly with blanchable erythematous macules and papules on the trunk and extremities, usually sparing the face (Fig. 7.13).
The exanthem is typically asymptomatic.

Diagnosis is based on clinical recognition and ruling out other eruptions that may require treatment or further investigation.
Identification of the exact etiologic agent is oftentimes not necessary or clinically feasible.

Differential Diagnosis

Drug Eruption

Pink-red blanching macules and papules that begin on the face and neck and spread caudally.
Pruritus is common.
History of inciting drug ingestion in the preceding 7 to 14 days.

Id Reaction or Id Dermatitis

An acute eczematous eruption characterized by itchy skin-colored to pink papules symmetrically distributed on the extensor extremities and trunk.
Also called autoeczematization, it is usually triggered by a severe inflammatory dermatosis such as allergic contact dermatitis, molluscum contagiosum, or fungal infections.

Kawasaki Disease

A small vessel vasculitis characterized by fever (lasting at least 5 days), conjunctivitis, oral mucosal erythema, cervical lymphadenopathy, and erythema of the palms and soles in addition to a widespread, nonspecific eruption.

Management

Nonspecific viral exanthems are usually self-limited and the eruption resolves over 1 to 2 weeks.
Supportive treatment with antipyretics, hydration, and use of bland emollients is generally sufficient.
If pruritus is present, topical corticosteroids are occasionally helpful.

Point to Remember

Nonspecific viral exanthems are the most common viral exanthems seen in children and are one of the chief reasons for pediatric urgent care visits.