Background: Periodic fever, aphthous stomatitis, pharyngitis, and cervical adenitis (PFAPA) is the most common periodic fever syndrome of childhood. Symptoms can include swelling of the glands in the throat, mouth ulcers, and tonsillitis. Removal of the tonsils can stop the periodic flareups. But researchers do not know how PFAPA develops. In this natural history study, researchers will collect specimens and data from people with PFAPA to see what they might have in common.

Objective: To collect blood and other specimens from people with PFAPA to learn more about the illness.

Eligibility: People aged 1 month or older with symptoms of PFAPA or another tonsil disorder.

Design: Participants will be screened. Their medical records will be reviewed. Researchers will ask about a family history of PFAPA. The following specimens may be collected: Blood. Blood will be drawn either from a needle inserted into a vein or from a prick in the finger or heel. Mucus and cells. A stick with soft padding on the tip may be rubbed inside the nostrils or mouth. Stool. Saliva. Tissue samples may be taken if participants are having surgery to remove the tonsils or adenoids. Participants having surgery may also have a nasopharyngeal wash; salt water will be squirted into the back of the throat and then sucked back out with a syringe. Most participants will provide specimens only once. They can do this in person at the clinic; they can also have their local health providers send specimens to the researchers. Some participants may have optional follow-up visits over 10 years.