Clinical features of a large chronic ulcer on the genital and perianal region in HIV-infected patients can be a strong clinical clue for the diagnosis of herpes simplex infection

Herpes simplex infection presents as a large, chronic, genital, and perianal ulcer in immunosuppressed HIV-positive patients. However, the characteristic morphological feature for clinical diagnosis is unclear. This case series illustrates the morphological characteristics of large, chronic, herpes simplex ulcers at the genital and perianal region in four HIV-positive patients. The diagnosis of herpes simplex infection was confirmed by laboratory test and/or rapid response to acyclovir therapy. All four of our patients had consistent morphological features such as uniform depth, punched out edge and arcuate border on the genital and perianal ulcers, along with positive IgM and IgG antibodies to herpes simplex virus and/or rapid response to acyclovir. Such findings suggest that these morphological features may be the characteristic feature of large and chronic herpes simplex ulcer in HIV/ADS positive patients.