Recurrent fever

Recurrent fever: When temperature returns again and again

Recurrent or periodic fever is a condition characterized by three or more episodes of high temperature within six months. Fever episodes occur at certain intervals (usually at least 7 days apart), and in the periods between attacks the person feels completely healthy. This condition can be very exhausting and worrisome, as the cause often remains unclear, requiring thorough diagnostics to rule out serious diseases.

Frequent infections vs. True periodic fever

The most common cause of repeated temperature episodes in young children is simply frequent but unrelated viral infections. A child who has started attending kindergarten can get a cold 10-12 times a year, and this is considered within the range of normal. Each episode is a new infection.

True periodic fevers are a group of rare diseases associated with defects in innate immunity. They are called autoinflammatory syndromes. In these conditions the immune system periodically "turns on" without an infection, causing systemic inflammation and fever. The most common among them is:

• PFAPA syndrome: An acronym meaning Periodic Fever, Aphthous stomatitis, Pharyngitis, and cervical Adenitis (lymph node inflammation). Fever attacks occur with remarkable regularity, every 3-6 weeks.

Diagnostic approach

Diagnosing recurrent fever is a complex process that requires ruling out many conditions. A key role is played by a symptom diary, in which the patient or parents record the exact dates of fever onset and resolution, its height, and all accompanying symptoms (rash, joint pain, abdominal pain). This helps the physician see patterns and suspect a particular disease. If the cause remains unclear, the condition may be classified as fever of unknown origin.