Differential Diagnosis for Severe Abdominal Pain in a Post-Stem Cell Transplant Patient
Single Most Likely Diagnosis
- Graft-versus-Host Disease (GVHD): This is a common complication post-stem cell transplant, where the donor's immune cells attack the recipient's body. GVHD can cause abdominal pain due to gastrointestinal involvement, and a negative CT scan does not rule out this diagnosis as it can affect the mucosa and submucosa without significant structural changes visible on imaging.
Other Likely Diagnoses
- Infection: Post-stem cell transplant patients are immunocompromised, making them susceptible to a variety of infections, including those that cause abdominal pain like CMV gastroenteritis or bacterial infections.
- Veno-Occlusive Disease (VOD): Also known as sinusoidal obstruction syndrome, VOD is a complication of stem cell transplantation that can cause abdominal pain due to liver dysfunction and portal hypertension.
- Medication Side Effects: Many medications used in the post-transplant period can cause abdominal pain as a side effect, including immunosuppressants, antibiotics, and antifungals.
Do Not Miss Diagnoses
- Bowel Infarction: Although the CT scan is negative, bowel infarction due to venous or arterial thrombosis can present with non-specific findings early on. It's crucial to consider this diagnosis due to its high mortality rate if missed.
- Perforation: Free air may not always be visible on a CT scan, especially if the perforation is small or contained. Clinical suspicion should remain high, especially if the patient's condition deteriorates.
- Hemorrhage: Internal bleeding can cause severe abdominal pain and may not be immediately visible on a CT scan, especially if the patient is on anticoagulation or has a coagulopathy.
Rare Diagnoses
- Thrombotic Microangiopathy (TMA): A rare but serious condition that can cause abdominal pain among other symptoms, due to microvascular thrombi formation.
- Post-Transplant Lymphoproliferative Disorder (PTLD): Although more commonly associated with solid organ transplants, PTLD can occur after stem cell transplantation and cause abdominal pain due to gastrointestinal involvement.
- Hemophagocytic Lymphohistiocytosis (HLH): A rare, life-threatening condition that can cause abdominal pain as part of a systemic inflammatory response, often triggered by infections, autoimmune disorders, or malignancies in immunocompromised patients.