Differential Diagnosis
The patient's symptoms of constipation, abdominal distension, anaemia, and chronic pain in the right lower abdomen can be attributed to several possible diagnoses. Here's a categorized differential diagnosis:
Single most likely diagnosis
- B. Caecal cancer: This is the most likely diagnosis given the combination of symptoms such as abdominal distension, constipation, anaemia (possibly due to chronic blood loss), and chronic pain in the right lower abdomen, which is a common location for caecal cancer.
Other Likely diagnoses
- D. Carcinoid of caecum: Carcinoid tumors can cause similar symptoms, including abdominal pain, bowel obstruction symptoms (like constipation), and potentially anaemia if there's bleeding. However, they are less common than caecal cancer.
- A. Caecal volvulus: Although this condition typically presents with more acute symptoms of bowel obstruction, it could potentially cause chronic symptoms if partially obstructing or if the patient has had recurrent episodes.
Do Not Miss (ddxs that may not be likely, but would be deadly if missed.)
- Intestinal ischemia or infarction: Not listed among the options but crucial to consider due to the potential for severe consequences if missed. Chronic or acute ischemia could lead to similar symptoms, including pain and changes in bowel habits.
- Appendicular pathology (including appendicitis or appendicular carcinoid, C): While appendicitis is usually more acute, chronic or recurrent appendicitis could present with chronic pain. An appendicular carcinoid could also cause similar symptoms, especially if it leads to bowel obstruction or intussusception.
Rare diagnoses
- Other rare tumors or conditions: Such as lymphoma, metastatic disease to the caecum, or rare inflammatory conditions. These would be less common but should be considered if initial diagnoses are ruled out, especially with atypical presentations or lack of response to initial treatment.