Differential Diagnosis
- Single most likely diagnosis
- Gallstone ileus: This condition occurs when a gallstone enters the bowel through a fistula between the gallbladder and the intestine, causing a mechanical obstruction. The presence of air in the liver (pneumobilia) on the abdominal x-ray, along with the symptoms of bowel obstruction (cramping abdominal pain, distention, nausea, vomiting, and high-pitched bowel sounds), makes gallstone ileus a strong candidate for the diagnosis. The absence of free air and the specific pattern of air-fluid levels throughout the small bowel without gas in the colon also support this diagnosis.
- Other Likely diagnoses
- Adhesive small-bowel obstruction: This is a common cause of small bowel obstruction, especially in patients with a history of abdominal surgery, which can lead to adhesions. However, the patient's lack of surgical history and the presence of pneumobilia make this less likely.
- Small bowel lymphoma: Although less common, lymphoma can cause intestinal obstruction. However, it would typically present with more systemic symptoms and might not explain the pneumobilia.
- Do Not Miss (ddxs that may not be likely, but would be deadly if missed.)
- Mesenteric infarction: This is a life-threatening condition that can present with abdominal pain and signs of obstruction. The high pulse rate (tachycardia) could be indicative of a more severe condition like mesenteric infarction, which requires immediate intervention.
- Ruptured appendicitis: Although the symptoms and signs might not perfectly align with a typical presentation of appendicitis (especially given the lack of specific tenderness in the right lower quadrant), any condition that could lead to peritonitis and sepsis must be considered and ruled out promptly.
- Rare diagnoses
- Intussusception: This condition, where a part of the intestine telescopes into another, is more common in children but can occur in adults, often associated with a lead point like a tumor. It's less likely given the patient's presentation and the absence of a palpable mass.
- Cecal cancer: While possible, cecal cancer would not typically cause the acute presentation of obstruction with pneumobilia seen in this patient. It's a consideration for chronic or subacute symptoms but less likely in this acute scenario.