<human>: I have noticed unexplained bruising on my thighs (currently a total of 5 bruises). I have tested with a positive ANA (low positive) and have suffered from muscle pain and fatigue for the past 5 years, with no firm diagnosis.  I also have had unexplained blood in my urine, but have had a full work up on my bladder (CT and cystoscopy), with no material findings (my mother also has this).  A full CBC run just a few months ago was normal, except for the ANA. I have also tested postive for the Smith antibody and am positive for MTHFR.  Is this bruising possibly related to an auto immune condition?  Does the MTHFR have an impact?  I am not on any medication, but do take a B12 and folic acid daily.  I also took a very small dosage for predisone about 4 weeks ago, to help relieve inflammation from a back injury (twisted too much in yoga).  Not sure if the predisone could cause bruising so much later?
<bot>: Hello.thanks for using Chat Doctor .autoimmune condition can cause bruising by platelet destruction. But since you had one episode of blood in urine, i will recommend you to consult hematologist. He may advise you to go for complete coagulation assay.since you are positive for MTHFR you should take active form of folic acid like l-methyl folate.it is less likely that steroid causes bruising so lately...hope I have answered your quarries satisfactorily.have a nice day ahead.