Differential Diagnosis for a 16-year-old girl with diarrhea, tiredness, abdominal pain, and elevated stool fat
- Single most likely diagnosis:
- C. Cystic fibrosis: This condition often presents with gastrointestinal symptoms such as diarrhea and malabsorption, leading to elevated stool fat (steatorrhea). The quantitative estimation of fat in stools (8 g/24 hours) supports this diagnosis, as cystic fibrosis can cause pancreatic insufficiency, leading to fat malabsorption.
- Other Likely diagnoses:
- D. Irritable bowel syndrome (IBS): Although IBS can cause diarrhea and abdominal pain, the significant elevation in stool fat is less typical for IBS. However, it remains a consideration due to the overlap of symptoms.
- Celiac disease: Not listed among the options but should be considered in the differential diagnosis for chronic diarrhea, abdominal pain, and malabsorption, including steatorrhea.
- Do Not Miss (ddxs that may not be likely, but would be deadly if missed.):
- None of the provided options directly fit into the "do not miss" category based on the deadly if missed criterion. However, Cystic fibrosis could be considered here due to its potential for severe complications if not promptly diagnosed and managed.
- Rare diagnoses:
- A. Insulinoma: This is a rare tumor of the pancreas that produces excess insulin, leading to hypoglycemia. While it could cause symptoms like tiredness, it does not directly explain the gastrointestinal symptoms or steatorrhea.
- B. Nephritic syndrome: This condition is characterized by inflammation of the kidneys and typically presents with hematuria, proteinuria, and hypertension. It does not directly relate to the gastrointestinal symptoms described, making it an unlikely diagnosis in this context.
It's essential to note that the provided options do not cover all possible diagnoses for the symptoms described. A comprehensive diagnostic approach would consider other conditions such as inflammatory bowel disease, chronic infections, and other causes of malabsorption.