Herpes zoster mandibularis.

To cite: Hsieh JW, Costa de Araujo P, Lechien J, et al. BMJ Case Rep Published online: [please include Day Month Year] doi:10.1136/ bcr-2013-200136 DESCRIPTION A 54-year-old man presented with vesicular rash and burning pain on the left mandibule. Two days before, the patient had developed pruritus in the same region. Clinical examination revealed vesicles on an erythematous base on the left lower lip, cheek, chin (figure 1), anterior scalp around ear and the ascending helix (figure 2). The lesions were localised in the dermatome innervated by the third trigeminal branch. No oral lesion, facial palsy or hearing loss was observed. A clinical diagnosis of herpes zoster mandibularis was made. The patient was treated with intravenous acyclovir, analgesics and broad-spectrum antibiotics during 10 days for bacterial superinfection. At 2 months follow-up, the rash had resolved and no potential complication was reported. Varicella zoster virus is responsible for chickenpox and can remain in a latent stage in any sensory ganglia. Reactivation of the virus decades later can occur in a precise dermatome. Rarely, this condition known as herpes zoster is limited to the third trigeminal branch. The patient may describe pain, burning or itching in this dermatome. It is followed by apparition of pustulo-vesicular rash in the same area, which is pathogmonic. The diagnosis can be confirmed by direct immunoflurescence from swabs. Taste dysfunction is also reported. When rash does not occur, unilateral oro-facial pain may be the only sign and serological examination and PCR technology may be required. It can be complicated by postherpetic neuralgia, tooth exfoliation and mandibular osteonecrosis. The treatment is acyclovir and should be started within 48 h of the onset of the rash.