omental infarction is an uncommon mimicker of the acute appendicitis that demands emergent diagnosis to avoid the surgical management . approximately , 85% of the cases are reported in the adults , and only a smaller proportion of 15% in the pediatrics patients . we describe a pediatric patient presenting as the right iliac fossa pain in the pediatric emergency with a clinical diagnosis of acute appendicitis and was subsequently accurately diagnosed on ultrasound and computed tomography ( ct ) as omental infarction and was successfully managed conservatively . a 4-year - old male child presented to the pediatric emergency with persistent acute colicky pain in the right iliac fossa of 2 days duration . vital signs were normal with a heart rate of 82 beats / min and blood pressure of 116/68 . on examination , there was rebound tenderness and guarding in the right iliac fossa . he was referred for an ultrasound examination with a strong clinical diagnosis of acute appendicitis . abdominal ultrasound revealed a well - defined triangular area of hyperechogenicity in the omental fat at the site of maximum tenderness , adjacent to the ascending colon . there was increased peripheral color flow on color and power doppler evaluation [ figure 1a and b ] . it depicted the characteristic 4.3 cm  1.2 cm  3.9 cm nonenhancing solitary heterogeneous fatty lesion in the right lower abdomen beneath the anterior abdominal wall anterior to the ascending colon , with surrounding inflammatory fat stranding . twisting and swirling of the vessels were seen within the lesion likely the thrombosed omental veins [ figure 2a and b ] . on retrospective history , the child had the history of painful stretching exercise in the school , just the day prior to the episode . a diagnosis of omental infarction was made , and the patient was discharged from the emergency department with anti - inflammatory and antibiotics medication . on subsequent follow - up , there was subsidence of pain and tenderness with a decrease in the size of the lesion on ultrasound evaluation after 6 weeks [ figure 2c ] . ( a ) well - defined focal hyperechoic area of fat abutting the anterior abdominal wall adjacent to the ascending colon . ( b ) color doppler may show increased surrounding vascularity ( a ) computed tomography axial scan shows encapsulated fatty lesion abutting the anterior abdominal wall adjacent to the ascending colon . ( b ) computed tomography axial scan shows twisting and swirling of the vessels ( arrow ) with surrounding fat stranding likely the thrombosed omental veins . ( c ) ultrasonography done after 6 weeks shows reduction in the size of the hyperechoic lesion ( arrow ) abutting the anterior abdominal wall right iliac fossa pain is a common complaint in the pediatric population with acute appendicitis as the most common clinical diagnosis . more than 0.1% cases of the acute appendicitis turned out to be omental infarction on laparotomy . thus , imaging plays an important role in the proper patient selection and treatment . primary omental infarction occurs due to the inherent tenuous arterial supply , kinked venous drainage and torsion of the arterial and venous supply , without other identifiable cause . secondary omental infarction occurs in the presence of other predisposing conditions such as surgical trauma , localized inflammation , or tumor . ct scan and ultrasound are the mainstay of diagnosis for the children with right iliac fossa pain and acute abdomen . ultrasound shows the well - defined focal hyperechoic area of fat abutting the anterior abdominal wall at the site of maximum pain . the increased vascularity can be depicted around the lesion on the color doppler evaluation due to the surrounding inflammatory reaction . enhanced ct scan reveals an oval / triangular encapsulated fatty lesion , commonly more than 5 cm that is abutting the anterior abdominal wall adjacent to the ascending colon . ct scan also provides additional information about the mesenteric vasculature , bowel , peritoneum , and retroperitoneum . the other differentials of the right iliac fossa pain in a child are acute appendicitis , meckel 's diverticulitis , epiploic appendagitis , mesenteric adenitis , and neutropenic typhlitis . in the previous era , the diagnosis of the omental infarction was made only on laparotomy , however with the advent of current imaging modalities ( ct / ultrasonography ) this uncommon entity can be diagnosed preoperatively with precision . the mainstay treatment for the omental infarction remains conservative with proper hydration , intravenous antibiotics , and anti - inflammatory drugs . there is a gradual resolution of the lesion over the period of time with relief in the pain and tenderness . omental infarction is a self - limiting disease that can be accurately diagnosed on imaging and can be differentiated from the more common causes of right iliac fossa pain like acute appendicitis . it helps in deciding the appropriate mode of management and avoids inadvertent surgical intervention . a high index of suspicion is required to identify these acute conditions on ultrasound .
omental infarction is an uncommon cause of acute abdomen in the pediatric population . 
 we report a case of a 4-year - old male child with right iliac fossa pain . 
 the final diagnosis was made on ultrasound and computed tomography findings . 
 this entity needs to be differentiated from acute conditions like appendicitis , avoiding surgery .