Yes, certainly, but presuming that U/d (units per day (?)) is the same as the internationally accepted IU (international units), then David's and other's recommendation of 4000iu of vitamin D for people with MS falls a long way short of 50 000 U/d.
This might also be useful:
By all means anyone should have themselves tested, especially if they experience any of the following symptoms: loss of appetite and nausea, weakness and nervousness that can't be explained by other reasons, vomiting, followed by excessive thirst and high blood pressure.
What do you think of the immunosuppressive properties of 1,25-dihydroxyvitamin D3? And can a Chlamydia Pneumoniae infection cause elevated levels?
As for the immunosuppressive properties vitamin D, yes, it undoubtedly does and this must be beneficial in treating CPn infection, because you don't want the immune system to go into overdrive when clearing things out with metro/flagyl. You want things to happen gradually, unlike what often happens with meningococcal septicaemia, where there can be such an overload of toxins as the septicaemia is tackled, where the patient can be dead within a couple of hours as they just can't cope with it. Doxycycline and minocycline are similarly immunomodulatory.
I should doubt if a CPn infection would cause elevated levels of 1,25-dihydroxyvitamin D3, because it wouldn't be suggested as a supplement for MS and other CPn infections.