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"Why do I get a fever of 100 deg. F every few days?"


I am a 34 year old engineer, and I get a recurring fever of 100 deg. F every few days. I have been to the tropics recently, and I thought I contracted malaria. I tested negative for malaria, and my doctor and I are stumped. I have no other symptoms and am not taking any medications except a multi-vitamin. I am 5 feet 6 inches tall and weigh 160 lbs. I am lactose intolerant and cannot eat shellfish.


Your symptoms are concerning. There are many possible causes, some of which are serious and some of which are minor. I would recommend that you discuss this with your primary care doctor.

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If stumped, it may be worthwhile seeing an Infectious Disease specialist. He or she may be able to further guide you. There are three broad categories for cyclic fever. The first and most common is infectious. There are a few infections that can cause this. Some of the notable ones are malaria, tuberculosis (or TB) and brucellosis. That being said, many other are possible like and abscess. Some people, if having gone to the right places and without prophylaxis might suggest you treat yourself for malaria despite a negative test as the test isn't always perfect. At a minimum, a repeat test might be warranted, preferably while you are having the fever. The two other broad categories are rheumatologic and oncologic. Rheumatologic refers to autoimmune disease like lupus or scleroderma. Normally there are other localizing symptoms that would point to one of these. Oncologic refers to a cancer, which is a rare cause. Normally, this fever can be caused by a leukemia or a lymphoma, but other cancers are possible. Talk to your doctor. Good luck!

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