BACKGROUND Intussusception is a rare pathological entity in adults and remains a diagnostic challenge for clinicians, as it shares many clinical signs and symptoms with other morbid conditions (including appendicitis, abdominal hernias, colic, volvulus, and Meckel diverticulum). High clinical suspicion and use of appropriate imaging techniques are essential for early diagnosis and treatment of intussusception. Surgical intervention is the treatment of choice in cases of sustained and persistent invagination. CASE REPORT We present the case of a 65-year-old woman with a medical history of Crohn's disease, diabetes mellitus type II, hypertension, and rheumatoid arthritis. She was hospitalized for diarrhea, fatigue, and anemia. Computerized tomography of the abdomen and a colonoscopy revealed telescoping of the ileum, ileocecal valve, and part of the ascending colon inside the terminal segment of the ascending colon. The antegrade ileocolic intussusception was treated by performing a right hemicolectomy. The pathologic examination of the excised intestine showed mucosal lesions compatible with Crohn's disease, an inflammatory fibroid polyp at the terminal section of the ileum, and a low-grade appendiceal mucinous neoplasm. CONCLUSIONS Regardless of the etiology, when the normal motility of the intestine is altered, it can lead to invagination. Although intussusception is rare, it must always be part of the differential diagnosis for a patient presenting with constant abdominal pain.