Background <p>Most acute abdominal pain raises the suspension of infectious or inflammatory processes. The most obvious sign of acute intra-abdominal inflammation is frequently the identification of inflamed fat on the ultrasound. The study aimed to determine the specificity and sensitivity of focal hyperechogenic fat sign as a localizer of abdominal pathologies and to correlate findings with other imaging modalities as well as operative and pathological data.</p> Results <p>Seventy-six patients with abdominal pain have been examined by ultrasound. In 32 patients (42.1%), focal hyperechogenic fat sign was the only detected sign by ultrasound; however, it was associated with other findings in 44 patients (57.9%). In 16 patients (21.1%), echogenic fat represents the primary source of pathology, while in 59 patients (77.6%), underlying pathologies were detected, &amp; the echogenic fat was a secondary finding. The diagnostic performance of hyperechogenic fat signs shown in the US in detecting the cause of abdominal pain was true-positive sign in 75 cases &amp; false positive in one case. Its sensitivity is high. It was about 98.7%.</p> Conclusion <p>Our investigation demonstrated that focal hyperechoic mesenteric fat sign on abdominal ultrasound exhibited exceptionally high diagnostic performance, with a sensitivity of 100% and accuracy of 98.7% in detecting potential intra-abdominal pathologies. However, these findings necessitate validation through larger, multi-center prospective studies to establish broader clinical applicability.</p>