Role of Ultrasound-Guided Fine-Needle Aspiration Cytology of Omentum in Diagnosis of Abdominal Tuberculosis

Abstract

To evaluate the efficacy of ultrasound-guided (USG) fine-needle aspiration cytology examination (FNAC) of the omentum in the diagnosis of abdominal tuberculosis (TB). Retrospective review was conducted of data from patients who presented with clinically suspected peritoneal TB between June 2016 and April 2018. We included patients in whom imaging showed omental thickening with or without ascites. Additional features that were assessed on imaging included ascites, the presence of mesenteric or retroperitoneal adenopathy, ileocecal thickening, and involvement of solid abdominal organs. Ultrasound-guided FNAC of the omentum was performed using a 22-gauge needle. The cytologic assessment was done for granulomatous inflammation, bacilli on Zeihl-Neelson stain, and for other pathology if any. During the study period, 35 omental FNACs were done. Of these patients, malignancy was reported in eight (22.8%). Of the remaining 27 patients, positive results for TB were reported in 19 patients (70.4%). In these 19 patients with positive FNAC, the median age was 33 years (range 10-63 years), with eight males (42.1%). Ascites was present in 14 (73.7%), abdominal lymphadenopathy was present in 9 (47.4%), ileocecal thickening and involvement of solid abdominal organs were reported in 3 (15.8%) and 4 (21%) patients, respectively. Granulomatous inflammation was reported in 17 (89.5%) and acid-fast bacilli in 10 (57.6%) patients. The Genexpert analysis was done in two patients, with a positive result in one patient. Ultrasound-guided FNAC of the omentum is helpful to diagnose abdominal TB in patients having omental thickening with or without other abnormal findings.