Mpox Presenting as Proctitis in Men Who Have Sex With Men.

In our cohort of 70 patients of men who have sex with men (MSM) with mpox, more than one-third presented with proctitis. In two-thirds of proctitis patients, there was no typical rash upon presentation, and in one-fifth, there was no rash at all, making the diagnosis a challenge. A rectal swab for mpox polymerase chain reaction (PCR) can be diagnostic.