Differential diagnoses: They are the possible causes of a set of signs and symptoms in medicine.

An example of this can be found in Robert H. Seller’s book Differential diagnosis of common complaints. If a patient presents with bloating and flatulence, the author suggests the following differential diagnoses:

1. Excessive intestinal bacterial fermentation;

2. Increased awareness of normal amount of gas;

3. Malabsorption;

4. Lactase deficiency (leading to lactose intolerance);

5. Giardiasis (commonly known as “beaver fever”, meaning a parasitic disease, not an infatuation with a certain furry animal);

6. Gas entrapment in the splenic flexure or the hepatic fixture.

By asking further questions and requesting the right diagnostic tests, a physician can eliminate these potential diagnoses until only the correct one remains.