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What is A 56-year-old man has painful weeping rashes over the upper eyelid and forehead for the last 2 days along with ipsilateral acute punctuate keratopathy. About a year back, he had chemotherapy for Non-Hodgkin's lymphoma. There is no other abnormality. Which of the following is the most likely diagnosis? and explain in detail?
It is a case of infection with Herpes Zoster.
The point which leaves no doubt about the diagnosis of Herpes zoster


Painful (unilateral) rashes over upper eyelid and forehead
H/O chemotherapy for Non-hodgkin's lymphoma
Ipsilateral acute punctate keratopathy


Herpes infections are characterized by pain and its occurrence in an immunocompromised patient.
Patients with Hodgkin's disease and Non-Hodgkins lymphoma are at great risk of developing progressive herpes zoster.