A 34-years-old pregnant woman admitted in the emergency unit complaining about worsening right iliac fossa pain for 2 days. Acute appendicitis was the suspected diagnosis. Laboratory exams were ordered and results were within normal limits for infectious and inflammatory aspects. Ultrasound scan revealed a pregnancy in course without alterations and a thickness of the appendix wall without inflammatory signs in the surrounding tissue. Because the suspicion of acute appendicitis remained, a magnetic resonance was done and confirmed the diagnosis of a cecal appendix lipomatosis.