The Case of an Itchy Scalp and Forehead Rash

This rash developed about 10 days ago and coincided with the onset of intense puritus in the 77-year-old woman's scalp.

In addition to the urticarial wet plaque on her right forehead, the patient also has smaller pink urticarial lesions on her temple and eyelid.

This is tache noir (black escar), with disseminated pustules after house mouse exposure.

With a classic zoster presentation, it is not necessary to do a confirmatory test. Special tests can be done to support a diagnosis in doubt.

This patient's presentation is somewhat atypical -- ie, the lack of vesicular eruption or pain plus presence of itching and eyelid edema. A Tzanck prep was done on a specimen obtained from her forehead lesion. Multinucleated giant cells were NOT identified and the prep was read as negative. This is a false negative result, however.

Herpes zoster can also cause mild fever, malaise, myalgia, and disseminated pruritic macules, papules, and vesicles.