65 year old female presents with a 2 week history of lower abdominal pain and dysuria. The patient is febrile (38.1 degrees). Her vital signs are: HR 104bpm, BP 130/80mmHg, 18 breaths/min, 98% on room air. She has a markedly tender lower abdomen.
A CT Abdomen and Pelvis is performed with IV and oral contrast. Review the scan and identify the primary pathology which explains the patient's symptoms. What is the likely cause of this problem?