TY - BOOK AU - Badiola, Jose Adolfo R. TI - Mistaken identity: “a rare case of acute appendicitis complicating portal vein and superior mesenteric vein thrombosis” / : [author]: Badiola, Jose Adolfo R AV - RAD 2024 0001 PY - 2024/// CY - Fairview, Quezon City PB - Department of Radiology, FEU-NRMF N1 - Includes bibliographical references; RESDR N2 - ABSTRACT: Acute appendicitis is the most common cause of surgical abdomen worldwide with an incidence of 233 per 100,000 population per year. The incidence gradually rises from birth, peaks in the late teen years, declining in the geriatric years. Cases may either be simple or may be complicated by gangrene, abscess or perforation. If not diagnosed and treated, it may rupture causing life-threatening infections.Other recognized complications include pylephlebitis (infective thrombophlebitis) and hepatic abscess. Portal vein thrombosis, a life-threatening condition, is most commonly caused by hepatic cirrhosis secondary to portal hypertension. Other causes may also include hepatobiliary malignancies, hypercoagulable states, and inflammatory processes. According to Fusaro et.al (2023), Pylephlebitis, also known as infective thrombophlebitis of the portal vein, is a very rare condition with an incidence of 0.37 to 2.7 cases per 100,000 person.This severe condition poses significant morbidity and mortality which usually develops as a complication of intra-abdominal suppurative process. Computed tomography (CT scan) is highly sensitive and specific in the diagnosis of acute appendicitis. However, ultrasound remains the initial diagnostic imaging modality of choice specifically in young individuals due to the absence of ionizing radiation and its availability in various centers. Acute thrombosis on the other hand may be difficult to detect using grey-scale imaging but a color Doppler may demonstrate absence of flow suggesting thrombosis. The use of CT scan preferably a contrast-enhanced study may reliably demonstrate portal vein thrombosis. This case report aims to present a rare case of acute appendicitis complicated by portal vein and superior mesenteric vein thrombosis which was later resolved through medications. Patient presented with fever, generalized abdominal pain, nausea, and vomiting. Initially during his work up, complete blood count and whole abdomen ultrasound only revealed cholecystolithiasis and gallbladder polyps. A whole abdominal CT scan was done for further evaluation revealing a prominent sized inflamed appendix with phlegmon formation. Likewise, a filling defect involving the portal vein extending to the superior mesenteric vein was demonstrated indicating presence of thrombosis ER -