Hi M4ggy,

Mono is associated with the Epstein Barr virus - but I'm guessing they've checked that out already - however it can reoccur and lead to auto-immune conditions.

There are several endocrine disorders that could be associated with the symptoms.

Low BP, dizziness, nausea, abnormal gait, muscle weakness, stomach, joint and back pain, extreme fatigue, cognitive dysfunction can all be signs of adrenal insufficiency (Addison's Disease). This is a rare condition so it may not have been looked for in your first endocrine work-up - are you able to get copies of any test results that were done back then? The first one to look for would be an 8am fasting blood cortisol test.

Addison's also has a few other distinctive symptoms which may help you rule it out: loss of appetite but craving salty and citrus foods - avoiding things like bananas (high in potassium). Patches of dark skin pigmentation appearing or dark creases in joint areas.

There are others I'm not so familiar with; Cushings Syndrome, pituitary disorders, Para hypothyroidism. There are also Malabsorption syndromes which can lead to your body not getting sufficient or the right nutrition.

Good luck with getting some answers.