• Eye Spy
  Title: What do you see?

  CT abdomen and pelvis in the coronal plane

  Numbered Findings:

  1.  Enhancing thickened and narrowed terminal ileum (pink arrowhead) and cecum (red arrowhead.
  2. Loculated ascites (yellow asterisk.
  3. Free Fluid (yellow asterisk)
  4. Omental cake (white arrowheads)

   

• Differential Diagnosis:
  1. Malignancy (e.g., Adenocarcinoma, Lymphoma, or Appendiceal Tumors):
     • Cecal or ileal tumors can cause bowel thickening and luminal narrowing.
     • Appendiceal tumors (e.g., mucinous neoplasms, adenocarcinomas) can cause omental caking and ascites, mimicking peritoneal carcinomatosis.
     • Lymphoma: May occasionally cause omental caking, often with lymphadenopathy or bulky mesenteric masses.
     • Clinical context: Older patients, systemic symptoms like weight loss, and absence of granulomatous inflammation.
  2. Gastrointestinal Tuberculosis (GI TB):
     • Commonly involves the terminal ileum and cecum.
     • Associated with granulomatous inflammation, focal bowel thickening, ascites, and omental caking.
     • Mycobacterium bovis: More frequently linked to ingestion of unpasteurized dairy products (prevalent in Africa, South Asia, and Latin America).
     • Mycobacterium tuberculosis: Can cause ileocolic disease via hematogenous or lymphatic spread, particularly in active pulmonary or miliary TB.
  3. Crohn’s Disease:
     • Chronic inflammatory bowel disease with characteristic skip lesions.
     • Thickened bowel walls and narrowing may overlap with other conditions.
     • Ascites and omental caking are uncommon.
     • Key point: Omental caking is not usually seen in Crohn’s disease, and its presence would effectively exclude this diagnosis.
     • Clinical context: Younger patients, perianal disease, and extraintestinal symptoms (e.g., arthritis).
  4. Yersinia Enterocolitica Infection:
     • Mimics TB in the ileocecal region with wall thickening and mesenteric lymphadenopathy.
     • Ascites is less common, and omental caking is rarely seen.
     • Key point: Omental caking’s presence would exclude this diagnosis.
     • Clinical context: Febrile illness and gastrointestinal symptoms after ingestion of contaminated food.
  5. Amoebiasis:
     • Caused by Entamoeba histolytica.
     • Leads to colonic thickening and possibly cecal involvement.
     • Ascites is less typical, and omental caking is not a common feature.
     • Key point: Omental caking’s presence would effectively exclude amoebiasis.
     • Clinical context: History of travel to endemic areas.
  6. Actinomycosis:
     • Rare bacterial infection presenting as mass-like bowel thickening, often mimicking malignancy or TB.
     • Fistulas and abscesses are common.
     • Omental caking is very rare in actinomycosis.
     • Key point: Omental caking’s presence would exclude this diagnosis.
     • Clinical context: Dental infections or GI trauma as potential predisposing factors.

  Comment:

  • Omental caking is a key radiologic finding often associated with gastrointestinal tuberculosis, malignancy (particularly appendiceal neoplasms or peritoneal carcinomatosis), and occasionally lymphoma.
  • Its presence significantly narrows the differential diagnosis by excluding conditions like Crohn’s disease, Yersinia enterocolitica infection, and amoebiasis, which rarely cause omental caking.
  • Clinical correlation is essential to determine the underlying etiology.
  • Each of these entities requires targeted workup and management tailored to the clinical setting.

  Credit: Ashley Davidoff MD TheCommonVein.net b1511-00a (02Co)

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