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You report the following: hypercalciuria (excess calcium in urine) with calcium kidney stones; positive ANA tests; body aches; fatigue; chronic diarrhea. The positive ANA tests do tend to point toward a connective tissue/autoimmune condition, such as systemic lupus erythematosus (often simply called lupus) or sarcoidosis. Sarcoidosis can alter vitamin D metabolism, resulting in increased absorption of intestinal calcium, hypercalciuria, calcium deposition in the kidney (nephrocalcinosis), and possibly calcium kidney stone formation (calcium nephrolithiasis). Lupus can cause nephritis (kidney inflammation), but, in contrast to sarcoidosis, it does not usually involve kidney stone formation. Bone/joint and muscle pains often occur with connective tissue diseases. Marked fatigue is a common symptom reported with both lupus and sarcoidosis. Digestive system problems, including diarrhea, are common in lupus; gastrointestinal symptoms are rare in sarcoidosis unless a secondary condition is present (e.g., celiac disease, Crohn's disease, Whipple's disease, carcinoid tumor). Based on the data above, it is certainly possible that all of your symptoms are due to a single underlying condition. Your rheumatologist will work with you to determine the cause of the positive ANA tests, perhaps revealing a link to all of your concerns.