What is a recurrent fever?
Recurrent fever describes a fever that returns after a period of time with a normal temperature. The pattern, duration, and associated symptoms can provide clues to the underlying cause. While most common fevers last for a few days and resolve on their own, a fever that returns suggests that the body's immune system is being repeatedly triggered by something that has not been fully resolved.
Types and causes of recurring fevers
Understanding the different types of recurring fevers can help narrow down the potential causes. These fevers can follow specific patterns, which are often linked to different underlying conditions.
Intermittent fever
An intermittent fever is a type of recurring fever where the temperature spikes and returns to a normal baseline during the day. This can happen in predictable cycles and is often associated with common infections like viral illnesses, pneumonia, or urinary tract infections. Certain parasitic diseases like malaria also cause distinct patterns of intermittent fever.
Relapsing fever
Relapsing fever is a specific type of intermittent fever caused by Borrelia bacteria. It is characterized by episodes of high fever, headaches, and muscle pain that last for several days, separated by periods of normal temperature that can last up to two weeks. The bacteria are typically transmitted by ticks or lice, and proper diagnosis and treatment with antibiotics are essential.
Biphasic or 'saddleback' fever
A biphasic or 'saddleback' fever is characterized by an initial fever peak, followed by a brief period of normal or low-grade temperature, and then a second fever spike. This pattern is a key feature of diseases like dengue fever, where the second phase can coincide with the critical stage of the illness.
Periodic fever syndromes
This is a group of rare genetic disorders, also known as systemic autoinflammatory diseases (SAIDs), that cause recurring fevers not triggered by external infections.
- PFAPA syndrome: This condition, which mainly affects young children, causes high fevers lasting a few days and recurring at regular intervals (every 3 to 6 weeks). Associated symptoms include mouth sores (aphthous stomatitis), sore throat (pharyngitis), and swollen lymph nodes (adenitis).
- Familial Mediterranean Fever (FMF): The most common hereditary periodic fever syndrome, FMF episodes can be triggered by stress and are characterized by fever and painful inflammation in the abdomen, chest, or joints.
Chronic and autoimmune conditions
Chronic and autoimmune diseases can also cause recurring fevers due to persistent inflammation in the body.
- Autoimmune diseases: Conditions such as lupus and rheumatoid arthritis can trigger recurring fevers during flare-ups as the immune system attacks healthy tissues.
- Chronic infections: Some infections can linger in the body, causing fever to recur until the infection is completely cleared. Tuberculosis is a well-known example that can cause low-grade fevers over a prolonged period.
- Malignancies: In rare cases, certain cancers, particularly blood cancers like lymphoma, can manifest as a persistent or recurrent low-grade fever.
Seeking medical attention
While many recurrent fevers resolve on their own, some signs warrant a medical evaluation to determine the cause. Age is a significant factor in deciding when to seek care. Any fever in an infant under three months should be evaluated immediately by a medical professional.
For older children and adults, it is advisable to see a doctor if the fever:
- Lasts for more than three days.
- Exceeds 103°F (39.4°C).
- Is accompanied by severe symptoms, such as a stiff neck, severe headache, confusion, difficulty breathing, or chest pain.
- Goes away and comes back repeatedly.
Comparison of fever types
Understanding the distinct characteristics of different fever types can be helpful in identifying potential causes.
| Feature | Intermittent Fever | Relapsing Fever | Biphasic Fever | Periodic Fever Syndromes |
|---|---|---|---|---|
| Pattern | Spikes and returns to normal daily. | Cycles of fever followed by afebrile periods. | Initial fever, brief remission, then second fever peak. | Recurrent episodes, often with predictable intervals. |
| Cause | Infections (viral, bacterial), malaria. | Borrelia bacteria from ticks or lice. | Specific infections like dengue fever. | Autoinflammatory genetic disorders. |
| Duration | Daily fluctuations. | Episodes of 2-7 days, with 4-14 days without fever. | Two distinct peaks. | Varies by syndrome (e.g., PFAPA episodes last 3-6 days). |
| Associated Symptoms | Fatigue, body aches. | Chills, muscle and joint pain, headache. | Rash, headache, eye symptoms. | Mouth sores, sore throat, swollen glands. |
Conclusion
While a recurrent fever is most commonly the result of a persistent infection that clears up on its own, it can also signal a more significant underlying issue, from an autoimmune disorder to a genetic condition. Paying attention to the fever's pattern and any accompanying symptoms is critical for determining if medical intervention is required. Always consult a healthcare professional for persistent or concerning fevers, especially in young children or those with chronic conditions, to ensure a proper diagnosis and treatment plan. A doctor can help determine the specific type of fever and investigate potential causes, offering peace of mind and appropriate medical care when needed. For more information on fever management, you can consult reliable sources like the American Academy of Family Physicians, which offers guidance on recurrent fevers in children.
