enanthems

Enanthems are mucous membrane eruptions associated with certain diseases, particularly viral infections. The term is used to distinguish lesions of the mucous surfaces—from those on the skin, which are called exanthems. Enanthems may appear on the oral cavity, conjunctiva, genital mucosa, or other mucous membranes and can occur before, during, or rarely after a characteristic skin rash.

Common sites of enanthem include the buccal and oropharyngeal mucosa, where they may present as vesicles, ulcers, or small pinpoint spots. They are often noted in the diagnostic process when correlated with the patient’s overall clinical picture.

Notable examples:

- Measles (rubeola): Koplik spots are small bluish-white lesions with a surrounding redness on the buccal mucosa and are considered a classic enanthem that can precede the measles rash.

- Herpangina: small grayish ulcers on the soft palate and tonsillar pillars, caused by Coxsackie A virus.

- Hand-foot-and-mouth disease: vesicular or ulcerative lesions on the oral mucosa, often accompanied by skin lesions on the hands and feet, caused by Coxsackie A16 and enterovirus 71.

Clinical relevance: Enanthems help support diagnosis when observed alongside compatible exanthems or clinical syndromes. They are not disease-specific and must be interpreted within the broader clinical context.

Diagnosis and management: Diagnosis is clinical, sometimes aided by laboratory testing for the underlying infection. Management is supportive, focusing on hydration, pain relief, and oral care; treatment of the underlying illness is guided by the specific etiologic agent if needed.

Prognosis: Enanthems generally resolve as the underlying illness runs its course.