Orchitis in children most commonly occurs as a result of a viral infection.
- The virus that causes mumps is most commonly implicated as the cause of orchitis.
- Approximately one third of boys will develop orchitis from mumps infection.
- It is most common in young boys, and testicular inflammation typically develops 4-6 days after the onset of mumps.
- There are case reports of mumps orchitis occurring after immunizationwith the mumps, measles, and rubella (MMR) vaccine, but this is rare.
- Other less common viral organisms which can cause orchitis include varicella, coxsackievirus, echovirus, and cytomegalovirus (associated with infectious mononucleosis).