Differential Diagnosis for Severe Abdominal Pain

Single Most Likely Diagnosis

• Constipation: The presence of a moderate fecal load and the patient's history of no bowel movement for days following pain onset strongly suggest constipation as a primary cause of her symptoms. The scattered air within nondilated small bowel loops could be secondary to constipation or a minor, non-specific finding.

Other Likely Diagnoses

• Partial Small Bowel Obstruction: The scattered air within nondilated small bowel loops could indicate a partial obstruction, which might not be severe enough to cause significant dilation but could still cause significant symptoms, including severe abdominal pain and nausea.
• Adhesional Band or Internal Hernia: Given the patient's history of similar episodes, adhesional bands from previous surgeries or internal hernias could be causing intermittent obstruction, leading to her symptoms.
• Inflammatory Bowel Disease (IBD): Although not directly indicated by the X-ray findings, the patient's recurrent episodes of severe abdominal pain and the absence of other clear causes might suggest an underlying inflammatory process such as Crohn's disease or ulcerative colitis.

Do Not Miss Diagnoses

• Mesenteric Ischemia: Although the X-ray does not show pneumatosis intestinalis or portal venous gas, which are more specific signs of ischemia, the severe abdominal pain out of proportion to the physical examination and X-ray findings should always prompt consideration of mesenteric ischemia, a potentially deadly condition if missed.
• Intussusception: This condition, where a part of the intestine telescopes into another, can cause severe abdominal pain and obstruction. It's more common in children but can occur in adults, often with a lead point such as a tumor.
• Volvolus: A twisting of a portion of the intestine, which can cut off blood supply and lead to ischemia. It's a surgical emergency.

Rare Diagnoses

• Chronic Intestinal Pseudo-obstruction: A rare condition characterized by recurrent episodes of intestinal obstruction without any physical blockage. It could explain the patient's recurrent episodes of severe abdominal pain and absence of bowel movements.
• Ehlers-Danlos Syndrome: A genetic disorder that can lead to intestinal dysmotility and could potentially explain recurrent episodes of abdominal pain and obstruction-like symptoms without a clear mechanical cause.