Differential Diagnosis

The patient's presentation of acute abdominal distention, mild to moderate abdominal pain, and vomiting, combined with the findings on the abdominal radiograph, suggests several possible diagnoses. These can be categorized as follows:

• Single most likely diagnosis

  • Ogilvie's syndrome (Acute colonic pseudo-obstruction): This condition is characterized by significant colonic distension in the absence of a mechanical obstruction, often seen in elderly patients with underlying medical conditions such as dementia, limited mobility, and chronic constipation. The patient's symptoms and the radiographic findings are consistent with this diagnosis, making it the most likely.

• Other Likely diagnoses

  • Mechanical bowel obstruction: This could be due to various causes such as adhesions, hernias, or tumors. The patient's symptoms of abdominal distention, pain, and vomiting are consistent with a mechanical obstruction. However, the presence of dementia and limited mobility, along with chronic constipation, makes Ogilvie's syndrome more likely.
  • Constipation with fecal impaction: Given the patient's history of chronic constipation, it's possible that the acute presentation could be due to a significant fecal impaction causing obstruction and subsequent distention.

• Do Not Miss (ddxs that may not be likely, but would be deadly if missed.)

  • Mesenteric ischemia: Although less likely given the patient's presentation, mesenteric ischemia is a critical diagnosis that must be considered due to its high mortality rate if not promptly treated. It can present with abdominal pain out of proportion to physical findings, but the presence of vomiting and distention could also be seen in this condition.
  • Perforated viscus: This is a surgical emergency that requires immediate intervention. While the patient's symptoms could be consistent with a perforation, the radiograph would typically show free air under the diaphragm, which is not mentioned.

• Rare diagnoses

  • Volvolus: This involves the twisting of a portion of the intestine, which can lead to obstruction and ischemia. It's less common and might not be the first consideration given the patient's presentation, but it remains a possibility.
  • Intussusception: This is the telescoping of one segment of intestine into another, which can cause obstruction. It's more common in children but can occur in adults, often with a lead point such as a tumor. Given the patient's age and symptoms, this would be a less likely but not impossible diagnosis.