A very rare case of ileocolic and appendiceal intussusception with acute appendicitis

Abstract

Intussusception is a common cause of bowel obstruction in children, typically occurring in those under 3 years old and often idiopathic. Secondary intussusception is less common in pediatric patients and usually involves a pathological lead point. Appendiceal intussusception is rare, occurring in only 0.01% of appendectomy specimens, and can mimic other acute abdominal conditions, making preoperative diagnosis challenging. We report a case of a 7-year-old male who presented with a 3-day history of crampy right lower quadrant pain and nonbilious vomiting. Ultrasound revealed an ileocolic intussusception with a suspected pathological lead point. Further imaging identified a distended, non-compressible appendix within the intussusceptum, leading to a diagnosis of secondary ileocolic intussusception due to acute appendicitis. Hydrostatic reduction was initially successful, but the patient developed recurrent intussusception within 24 hours. Surgical exploration confirmed McSwain type 3 appendiceal intussusception, necessitating manual reduction and appendectomy. The patient recovered well postoperatively. Clinicians should maintain a high index of suspicion for appendiceal pathology in older children with intussusception, and thorough imaging evaluation is essential. Early recognition of an inflamed appendix as the lead point is critical to prompt appropriate surgical intervention, ultimately preventing further complications. This case contributes to clinical practice by emphasizing the need for tailored diagnostic and therapeutic strategies in managing rare, complex presentations of intussusception.

Keywords: Acute appendicitis; Appendiceal intussusception; Case report; Ileocolic intussusception; Ultrasound.

Fig. 1

RUQ transverse scan shows the terminal ileum (horizontal arrow) and echogenic mesenteric fat (curved arrow) telescoping into an edematous, thickened cecum (vertical arrow), appearing as a target sign.

Fig. 2

(A) RUQ longitudinal scan shows a distended, noncompressible appendix invaginating into the cecum as part of the intussusceptum, alongside the terminal ileum. (B) Transverse scan shows the intussuscipiens as a thickened cecum (horizontal arrow) and the intussusceptum as a distended appendix (stars), echogenic mesenteric fat (vertical arrow), and terminal ileum (cross).

Fig. 3

(A) Intraoperative image demonstrating a distended appendix (vertical arrow), and (B) distended erythematous appendix after manual reduction.