Final answer:
All three patients in the scenario have inflammation in different areas of the body.
Step-by-step explanation:
The relationship between the diagnoses in the given scenario is that all three patients have inflammation but in different areas of the body. Itching and having a problem with their digestive systems are additional symptoms that the patients experience, but these symptoms are not exclusive to all three patients. Therefore, the main commonality among the cases is the presence of inflammation in different parts of the body.