Unexplnd wieght loss-50lbs, 3 mths, tired same time every day, dizziness, regular bldwrk normal, basics cmp, cbc, TSH profile, did have wbc's abd crystals in ua, +lupusanticoag years ago. Ideas?

Need evaluation. Unintended weight loss of 50 lbs is a serious matter and needs to be investigated by more than usual blood tests. There is a long list of possible explanations. Detailed history, physical examination and other studies need to be done. See this site for info. http://www.mayoclinic.com/health/unexplained-weight-loss/my00713.
Weight loss. Weight is simply a balance of calorie consumed and then absorbed and finally used by body metabolic status if u are consuming calories you can rule out anorexia or conditions causing it you need to rule out malabsorbtion with go work up metabolic abnormality seems to be ruled out.