Thicker than 3 mm over at least 5 cm of the bowel despite bowel lumen opacification (CT) and distention Ileal or ileocecal wall thickening may be present

enlarged lymph nodes are located anterior to the right psoas muscle in the majority of cases, or in the small bowel mesentery 6 CT is usually reserved for older patients if needed at all.ģ or more (very) tender nodes with a short-axis diameter of at least 5 mm clustered in the right lower quadrant (see normal mesenteric lymph nodes) 1,2 Radiographic featuresĪs mesenteric adenitis usually presents in the young, ultrasound is often the investigation of choice. Occasionally in young children and infants, ileocolitis may be also present suggesting that the lymph node involvement may be secondary to a primary enteric pathogen. Yersinia enterocolitica is considered the most common pathogen in temperate Europe, North America and Australia. Variety of viruses, including Epstein-Barr virus and probably COVID-19 10 Mesenteric adenitis has a number of causes: On microscopy, there is non-specific hyperplasia and when suppurative, there is necrosis and pus. On gross pathology, lymph nodes are enlarged and soft. The pathogenic micro-organisms are thought to gain access via intestinal lymphatics and then multiply in mesenteric lymph nodes.

Definitive diagnosis at surgery is possible but is increasingly uncommon due to the ubiquity of modern imaging tools. Mesenteric adenitis is often a diagnosis of exclusion after 'more serious' etiologies have been ruled out. Presentation is similar (or can be identical) to acute appendicitis, hence is a differential diagnosis for right iliac fossa pain. Mesenteric adenitis is most common in children and adolescents although it may occasionally affect adults.

Shotty lymph nodes differential