Acute Non-Traumatic Urinary Tract Emergencies: The Central Role of CT Imaging and the Emerging Role of Photon-Counting CT

Acute non-traumatic urinary tract emergencies are a frequent cause of emergency department presentation and may result in significant morbidity if not promptly diagnosed. Imaging plays a pivotal role in identifying the underlying pathology, assessing disease severity, and guiding patient management. This review provides a comprehensive imaging-based overview of the most common acute non-traumatic urinary tract emergencies. Obstructive, infectious, vascular, and hemorrhagic conditions, as well as urinary leaks, are discussed with emphasis on their characteristic imaging findings. The roles of ultrasound, computed tomography, and magnetic resonance imaging are reviewed, highlighting appropriate modality selection in the emergency setting. In addition, the emerging role of photon-counting computed tomography (PCCT) is discussed. Owing to its improved spatial resolution, enhanced tissue contrast, and spectral imaging capabilities, PCCT may allow better detection of subtle parenchymal abnormalities, small calculi, vascular alterations, and urinary leaks, while potentially enabling dose optimization. Key diagnostic features, common pitfalls, and practical reporting considerations are presented to assist radiologists in achieving timely and accurate diagnoses. This review aims to support a systematic and clinically relevant imaging approach to acute non-traumatic urinary tract emergencies.