Right costophrenic angle abscess due to Dublin infection in combination with type 2 diabetes mellitus.

The main manifestations of type 2 diabetes mellitus are excessive drinking, polyphagia, polyuria and wasting or weight loss in a short period of time, but it is rare to have persistent fever of unknown origin as the main manifestation. This case report describes a 68-year-old male patient with type 2 diabetes mellitus presenting with unexplained fever with persistent exacerbation and a cystic lesion in the right costophrenic horn on abdominal computed tomography (CT). A cytoculture examination of the puncture fluid suggested that the infection was due to Dublin. The patient was treated with drainage of the abscess in the right costophrenic angle area, which then healed successfully. These findings suggest that Dublin infection should be considered when a patient with type 2 diabetes mellitus presents with an unexplained persistent fever. At the same time, CT-guided abscess puncture can be performed to improve the patient's symptoms, aid diagnosis and improve the quality of life.