Dual-isotope SPECT/CT impact on hospitalized patients with suspected diabetic foot infection

Abstract

Foot ulcer with suspected infection is one of the most common reasons for hospitalization and a major factor contributing to morbidity and high healthcare-related expenses among diabetic patients. Many patients will require amputation; however, major amputation is associated with an alarmingly high 5-year mortality rate. In this study, we assess the diagnosis and management of suspected foot infection in diabetic patients using dual-isotope (DI) single-photon emission computed tomography/computed tomography (SPECT/CT) compared with conventional imaging. The diagnostic accuracy in and management of 227 patients who had undergone DI SPECT/CT was compared with that of 232 similar patients who had undergone conventional imaging including plain radiography, CT, planar bone scanning, planar indium-111 white blood cell scanning, and MRI. The duration of hospitalization was additionally compared between these two groups of patients after excluding patients with other active comorbidities. Soft-tissue infection, osteomyelitis with or without soft-tissue infection, and other bony pathologies were more accurately and confidently identified with DI SPECT/CT than with conventional imaging. DI SPECT/CT use was associated with significantly fewer major amputations and more selective bony resection as well as with shorter duration of hospitalization when compared with conventional imaging. In this large population of diabetic patients with suspected foot infection DI SPECT/CT was more accurate in diagnosing and localizing infection compared with conventional imaging. In addition, DI SPECT/CT provided clear guidance and promoted many limb salvage procedures. Of equal importance to health economics, DI SPECT/CT use was associated with considerably reduced length of hospitalization compared with conventional imaging.