Your symptoms are suggestive of immune issue. An autoimmune panel would be good to start with. Since you have low iron, an anemia panel also would be important as following:
1) Complete blood count (CBC)
2) Peripheral blood film
3) Vitamin B-12
5) Reticulocyte count
7) Thyroid-stimulating hormone
8) Serum creatinine and estimated glomerular filtration rate
9) Serum ferritin
10) Serum iron
11) Total iron-binding capacity.
I feel you may have autoimmune disease especially with the history of ulcerative colitis. You may also get following:
1) Obtain cultures for bacteria, mycobacteria, and fungi (blood, urine, stool, sputum, spinal fluid).
2) Serologies for Brucellosis, CMV infection, amebiasis, toxoplasmosis, and chlamydial diseases.
3) Serum protein electrophoresis (SPEP) is useful in diagnosing SLE flares.
4) Serum ferritin levels are useful in cases of SLE flare, and adult Still disease
5) Antinuclear antibody titers, rheumatologic factor, thyroxine level, and ESR,
6) High resolution CT scan of lung and CT scan of chest.
7) Ultrasound and CT scan of abdomen.
8) Technetium bone scan
9) Liver function tests and kidney function tests.
10) Adrenal function tests.
11) Peripheral blood smear.
I am not sure about EBV. This may be concomitant. Primarily it may not be responsible for it.
Please feel free for your follow up questions.
I would be happy to assist you further, if you need any more information.
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