Mesenteric lymphadenitis; a common diagnostic mimic to acute appendicitis. With radiology it is no more a diagnosis of exclusion, laparoscopy or surgery

Abstract

Mesenteric lymphadenitis (ML) is an inflammatory response to viral infections, bacterial infections, inflammatory bowel disease, or lymphoma in the ileocecal regions. It is a common diagnostic mimic to acute appendicitis. It is a self-limited inflammatory process that affects mesenteric lymph nodes in the right lower quadrant (RLQ). We present a 15 year-old-girl with low grade fever and RLQ pain. Initial physical examination and laboratory investigations suggested acute appendicitis. However, diagnosis of ML was established by the finding abnormal lymph nodes that are usually: (a) clusters of > 3 tender ones anterior to right psoas muscle or in the small bowel mesentery, (b) > 5 mm in diameter of short axis, and (b) rounded in shape. In addition; the ileal or ileocecal wall is thickened (> 3 mm) over at least 5 cm of the bowel and the appendicular wall is normal and its lumen is patent. In conclusion; this case reports indicates tha with radiology; ML can be differentiated from acute appendicitis and limits the role of invasive laparoscopy or surgery in exclusion of the latter.
 Keywords: appendicitis, CT, mesenteric lymphadenitis, radiology, US.