Brief Answer:
Information

Detailed Answer:
Hello and welcome,

If you have been having actual fevers, and this has been going on intermittently for 3 or more weeks, and no obvious cause is apparent, I recommend that you go in to see your doctor to have an evaluation for "Fever of Unknown Origin".

FUO can be caused by a number of problems, from undiagnosed infection to autoimmune disorders.

It is standard to get all or most of the following tests initially:

Complete blood count (CBC) with differential
The differential is an automated count of different lines of white blood cells

Peripheral blood smear
This is similar to the CBC with differential only a person actually looks at the blood cells. They don't cover as many cells as is run through the machine with the automated test, but can look at size and shape of cells which gives clues to different illnesses.

Comprehensive metabolic panel (CMP)
Includes sodium, potassium, glucose, acid-base, kidney function indicators, and liver enzymes

Erythrocyte sedimentation rate (ESR)
The "Sed rate" will be elevated when there is any inflammation in the body, however, it is non-specific and doesn't indicate where or the cause of the elevation. However, it can be useful to see if there is inflammation and in some cases, to monitor this over time.

Urinalysis
looks for blood, bacteria, protein, sugar, ketones, which may be elevated in disease such as infections, autoimmune disorders, kidney inflammation, and diabetes

Blood cultures

TSH and T4 (thyroid stimulating hormone and free thyroxine)
To look for thyroid abnormalities

HIV serology - to check for HIV status

Tuberculosis screening tests

Chest Xray - to look for infection, inflammatory changes, masses

Antinuclear antibody titer (ANA) and Rheumatoid factor
To look for possible Lupus and rheumatoid arthritis

I strongly encourage you to keep a log of your fevers and infections. It's important to know how high your fevers are, and how often they occur, as well as how often infections occur and how long they take to heal.

So make an appointment, please, for a generous block of time with your doctor so that he or she can do a complete physical too. Even if your fevers are low grade, I would still evaluate this in the same way. Make sure to see a physician/MD and NOT a PA or NP.

In the meantime, do what you can to maximize a healthy lifestyle with adequate rest, decreased stress, good nutrition, and minimal alcohol. If you smoke cigarettes you absolutely need to quit.

If you are willing, please let me know how you are doing after you have been evaluated. And good luck.

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