GRHPR and Hyperoxaluria: To evaluate the contribution of genetic factors in the development of hyperoxaluria after bariatric surgery, we conducted tNGS to detect variations within genes known to cause monogenic hyperoxaluria and Ca-Ox-NL (AGXT, GRHPR, HOGA1; SLC26A1) as well as the candidate genes SLC26A6 and SLC26A7 (Fig. 2A).