Acute abnormalities in the spleen are frequently traumatic and include nontraumatic entities, which can be potentially life-threatening if not recognized and managed in a timely manner. In the nontraumatic setting, emergent splenic pathology can be identified on cross-sectional imaging obtained for left upper quadrant or otherwise nonspecific abdominal pain, as history and physical examination are often inconclusive. A wide spectrum of nontraumatic splenic pathology can be seen, ranging from vascular conditions to infections and inflammatory processes. Given the potential for high morbidity and mortality associated with most of these entities, radiologists must be familiar with these imaging features to prevent any delayed or missed diagnosis.