Photo Rounds
Dermatomal rash on a 6-year-old boy
The lesion on his trunk looked like zoster, but the patient had been vaccinated against varicella.
Several types of infection are in the differential diagnosis
Because the symptoms of Ramsay Hunt syndrome suggest a possible infection, the differential diagnosis should include herpes simplex virus type 1 (HSV-1), Epstein-Barr virus (EBV), group A Streptococcus (GAS), and measles.
HSV-1 can cause oral symptoms similar to Ramsay Hunt syndrome. However,
HSV-1 doesn’t cause vesicles in the ear. Also worth noting: Recurrent HSV-1 infections normally involve keratinized surfaces such as the vermilion border and gums, but rarely the hard palate.3
EBV can cause multiple systemic symptoms. It can cause leukoplakia in the mouth— most often on the sides of the tongue—but does not cause vesicles.4
GAS presents as a sore throat, fever, anterior cervical lymphadenitis, and a scarlatiniform rash. Oral manifestations can include tonsillar erythema with or without exudate, soft palate petechiae, and a red swollen uvula.5 Use of validated clinical prediction tools, such as the sore throat tool found at http://www.ncbi.nlm.nih.gov/pmc/articles/PMC1228750/pdf/cmaj_158_1_75.pdf, can help distinguish GAS infection from other conditions.6-8
Measles typically occurs in children and young adults. Infection in immunized individuals is rare. It presents with fever and the “3 Cs”—cough, coryza, and conjunctivitis. Koplik’s spots are blue to white ulcerated lesions on the buccal mucosa, typically opposite the first and second molars, although they can occur anywhere in the mouth. They precede the generalized maculopapular rash of measles.9