Imaging spectrum of Alveolar Hydatid as per PNM Classification.

Abstract

Introduction: There are two forms of infestation by Echinococcus: the unilocular cystic form caused by E. granuloses is much more common than the rare multilocular alveolar form caused by E. multilocularis. Without early diagnosis and treatment, disease has poor prognosis. Death eventually results from hepatobiliary complications like cholangitis or secondary biliary cirrhosis; bleeding from esophageal or duodenal varices due to portal hypertension, Budd-Chiari disease, or obstruction of the vena cava; or complications related to heart, lung, or brain involvement. Materials and Method: This was an observational study where a cohort of 24 patients with avascular hepatic mass on ultrasound were subjected to triple phase contrast computerized tomography over a span of two years from December 2020 to November 2022 in GMC, Srinagar. Aim: The aim of the study was to present the Imaging spectrum of alveolar Hydatid on CECT as per PNM classification and to assess characteristics of alveolar hydatid on contrast enhanced computed Tomography. Results: The most common form of alveolar hydatid in liver was an infiltrating non enhancing heterogeneous mass lesion with irregular margins with internal calcifications (75%) cases. Calcification was seen in 22(91.6%) out of 24 cases (P value < 0.001). All of the masses were non enhancing with peripheral rim enhancement in only 5 cases (20.8%). P2N0M0 was the most common stage found on CECT as per PNM classification in 14(58.3%) patients followed by P1N0M0 in about 4 patients (16.6%). P3 and P4 stage was found in 3 patients (12.5%) each. N1 stage was found in 2 patients (8.3%). M1 stage was found in 3(12.5%) patients with metastasis to lung in two cases and Brain in one case. Conclusion: CECT has a very important role to suggest diagnosis of Alveolar Echinococcosis since MRI take long acquisition times. Radiologists especially those residing in endemic region must be aware of imaging findings of Alveolar Echinococcosis so that they can direct clinicians to take proper therapeutic decision.