All the symptomology points to an immune reaction to some pathogen. Gastro problems then do the MetaMetrix test which is the best. It could well be protozoa which parasite cleanses won't touch (trust me) .... could be mycoplasma infection , could be a rogue bacteria stuck somewhere.
Do supportive nutrients, liposomal glutathione, vitamin c, vitamin d3 levels checked, vitamin A.
Look at Pure Herbs S.A. 4 product and cat's claw for killing power. Also warburgia could be quite helpful.