(BMJ)—A previously healthy 54-yo woman presented w/ a worsening ulcer, of 2 days’ duration, on her hard palate. Pain was assoc w/ numbness around the ipsilateral upper lip and cheek. Exam: afebrile; hypoesthesia on L upper lip and cheek; vesicles on L side of hard palate. What is the dx?
Intraoral herpes simplex virus
Recurrent aphthous stomatitis
Primary syphilis
Hand-foot-and-mouth dz
Herpes zoster
You are correct. The key feature is the dermatomal involvement of the lesions in the ipsilateral maxillary nerve distribution, typical for shingles caused by herpes zoster. Hand-foot-and-mouth dz occurs primarily in children. Primary syphilis and recurrent aphthous stomatitis usually appear as solitary, nonvesicular lesions on loose, nonkeratinized mucosa. Nevertheless, the presence of multiple vesicles on the L side of the hard palate can be indistinguishable from HSV infxn. Dx was confirmed by the presence of VZV-specific IgM and IgG antibodies, and the pt was started on antiviral tx.

Emergency Medicine Journal 2020;37:436-443.