Differential Diagnosis
- Single most likely diagnosis
- Fecal impaction: The patient's history of mild constipation, recent onset of severe constipation, and inability to pass stool, along with the CT scan findings of a large amount of stool in the distal colon, support this diagnosis. The patient's response to laxatives and normal bowel movements after treatment also suggest fecal impaction.
- Other Likely diagnoses
- Constipation-induced ileus: The patient's symptoms and CT scan findings could also be consistent with an ileus caused by constipation. The patient's recent dehydration and dietary choices may have contributed to this condition.
- Opioid-induced constipation: The patient's use of opioid pain medication could be contributing to their constipation, as opioids are known to cause constipation.
- Dehydration-induced constipation: The patient's admission of poor hydration in the days leading up to their constipation supports this diagnosis.
- Do Not Miss (ddxs that may not be likely, but would be deadly if missed.)
- Intestinal obstruction: Although the CT scan suggests that an underlying stricture or mass would not be excluded, the patient's response to laxatives makes this less likely. However, intestinal obstruction is a potentially life-threatening condition that must be considered.
- Colorectal cancer: Although the patient has no family history of colorectal cancer, it is still a possible cause of constipation and should be considered, especially given the patient's age.
- Volvulus: A twisting of the intestine that can cause obstruction and ischemia, which can be life-threatening if not promptly treated.
- Rare diagnoses
- Sigmoid stricture: The CT scan findings suggest that an underlying stricture or mass would not be excluded, but this is less likely given the patient's response to laxatives.
- Hirschsprung's disease: A rare condition characterized by the absence of ganglion cells in the distal colon, leading to severe constipation. However, this is typically diagnosed in childhood, making it an unlikely diagnosis in a 61-year-old patient.
- Parkinson's disease-related constipation: Although the patient's mother has Parkinson's disease, there is no indication that the patient has the disease themselves. However, it is worth noting that constipation can be a symptom of Parkinson's disease.