Incarcerated Amyand hernia: Previous warning signs on sonogram

The patient was an 11-month-old boy. He has been followed up at an outpatient clinic for inguinal hernia. He visited at our emergency room because of multiple episodes of vomiting. After receiving a diagnosis of incarcerated hernia, he underwent emergency surgery under general anesthesia. Intraoperative findings showed that not only the appendix but also the cecum, ascending colon, and end of the ileum had herniated, so we diagnosed him with expansive Amyand's hernia. None of the intestine was necrotic, and intestinal resection was not necessary, but there was significant ileocecal dilatation. Therefore, we resected the appendix and inserted a flexible catheter through the root of appendix to decompress the ileocecal lumen. If the ultrasound sonography at outpatient clinic had shown an appendix-like intestine with proper attention, we may have been able to diagnose him with expansive Amyand's hernia. It is crucial to check the diagnosis of hernia but also detailed contents of the hernia sac carefully by ultrasound sonography. If the appendix is confirmed with the intestine in the hernia sac, we should consider early elective surgery to avoid an emergency operation. •Amyand's hernia with herniation of the ileocecum must be diagnosed before incarceration occurs.•In inguinal hernia, we must try to detect the appendix as evidence of ileocecal herniation.•Ultrasonography at the time of incarceration shows significant edema, which often makes it difficult to detect the appendix.