The way the body recognises an infection is by examining molecules from the infectious agent.
Since as early as 200 BC, people began to use disabled or minute amounts of infectious agents to immunize themselves against infections.
If pericarditis is suspected, the history should address exposure to infectious agents, connective tissue and immune diseases, and previous diagnosis of neoplasia.
The problem is that the molecules antibodies recognise and react to are the big ones, such as proteins, that are characteristic of bacteria, viruses and other infectious agents.
If too much of the cuticle is cut back during a manicure, the cuticle can be separated from the nail, and infectious agents can get into the exposed area.