Differential Diagnosis for Concern of Bleeding

Given the significant drop in ferritin, iron saturation, and serum iron levels, along with a prior workup indicating small innumerable ulcerations in the small bowel suggestive of Crohn's disease, the following differential diagnoses are considered:

• Single Most Likely Diagnosis

  • Crohn's Disease with Active Bleeding: The prior workup showing small innumerable ulcerations in the small bowel, combined with the significant decrease in iron stores (ferritin from 93 to 44, iron saturation from 40 to 16, and serum iron from 165 to 55), strongly suggests that Crohn's disease is active and causing chronic blood loss, leading to iron deficiency anemia.

• Other Likely Diagnoses

  • Ulcerative Colitis with Bleeding: Although the initial workup pointed towards Crohn's disease, ulcerative colitis could also cause similar symptoms and lead to iron deficiency anemia due to chronic blood loss.
  • Non-Steroidal Anti-Inflammatory Drug (NSAID) Induced Ulcers: Long-term use of NSAIDs can cause gastrointestinal ulcers and erosions, leading to chronic bleeding and iron deficiency anemia.
  • Celiac Disease: This autoimmune disorder can lead to malabsorption of nutrients, including iron, and could potentially cause a decrease in iron stores, although it might not directly cause bleeding.

• Do Not Miss Diagnoses

  • Gastrointestinal Cancer: Although less likely, gastrointestinal cancers (e.g., colon, stomach, small intestine) can cause chronic blood loss leading to iron deficiency anemia. Missing this diagnosis could be fatal.
  • Angiodysplasia: These are vascular malformations in the gastrointestinal tract that can cause chronic, occult bleeding, leading to iron deficiency anemia.
  • Meckel's Diverticulum: A congenital anomaly of the small intestine that can cause bleeding, especially in younger patients.

• Rare Diagnoses

  • Hereditary Hemorrhagic Telangiectasia (Osler-Weber-Rendu Syndrome): A rare genetic disorder characterized by the formation of abnormal blood vessels, which can lead to chronic bleeding and iron deficiency anemia.
  • Blue Rubber Bleb Nevus Syndrome: A rare condition characterized by venous malformations that can cause gastrointestinal bleeding.
  • Gastric Antral Vascular Ectasia (GAVE): A rare cause of chronic gastrointestinal bleeding, characterized by vascular ectasias in the stomach.