I have a relative who suffers from AS for a really long time and I was wondering what lab tests would he need to do in order to get a status of his calcium metabolism and inflammation. He has a fusion of one of the hip joints, which prevents him to fully extend his leg and causes him to stay bent. Today he told me that he has pain in the problem area, which provoked me to look deeper into his condition. I believe that PTH, thyroid status, Ca and Vit D will be on top of the list but some inflammatory and rheumatoid markers are needed to form a more complete panel.