INTRODUCTION: Since the beginning of the mpox (previously called monkeypox) outbreak in 2022, almost half of cases in Denmark have been diagnosed at the Department of Infectious Diseases, Copenhagen University Hospital - Amager and Hvidovre Hospital. This article describes the patient cohort seen at the Department with a view to increasing knowledge of mpox among colleagues who are most likely to identify future cases.

METHODS: A retrospective observational study reporting patient characteristics, coinfections, clinical presentation and diagnostic delay among mpox cases diagnosed at the department between 23 May 2022 and 8 February 2023. Furthermore, a case report of a patient hospitalised with severe rectal pain is presented to highlight anorectal symptoms.

RESULTS: A total of 86 patients were diagnosed with mpox, all were men who have sex with men, with a median age of 39 years. Twenty-six patients (31%) took HIV pre-exposure prophylaxis, and 20 patients (24%) were people living with HIV. All patients (100%) presented with lesions, most frequently on or around the genitals. Twenty-nine patients (35%) had anorectal discomfort or pain. Seven patients (10%) had chlamydia, 19 (26%) gonorrhoea and two (5%) syphilis. In 13 cases (15%), mpox was not suspected at the first medical consultation, mainly because symptoms were attributed to a gonorrhoeal coinfection. Five patients (6%) were hospitalised for a median of three days.

CONCLUSION: As mpox may become endemic in Denmark, clinicians should remain aware of its symptoms and the risk of coinfection with sexually transmitted infections.

FUNDING: None.

TRIAL REGISTRATION: Not relevant.