What causes recurrent fevers?

Q: What could be the reasons for feeling feverish? Sometimes I feel very feverish but the thermometer reading is normal. I also get severe body ache (body also gets warm) and this lasts for 4 - 5 days after which I become normal. The cycle repeats after (almost)2 weeks. I had several tests but there is absolutely no indication of any type of infection. There is no loss of weight. Is anything wrong with the brain? This has been so for last 2 years. Please reply.

A:Recurrent fevers may be caused by infections (e.g., tuberculosis, brucellosis, or even malaria), collagen vascular diseases (such as arteritis or lupus erythematosus), or malignant diesease (e.g., lymphoma). However, if appropriate tests are all negative, these diagnoses are very unlikely. Nevertheless, if the symptoms persist, then the tests may need to be done again. Sometimes feverishness is caused by medications or allergies. Stress, autonomic nervous system imbalance, eticholanolone surges, or unusual biorhythms can be responsible and nothing can be achieved by conventional medical therapy. Fortunately, the symptoms tend to go away if they are ignored.