In a more recent study by Gomez-Gomez et al. [86], only urinary Kyn and AA levels were significantly elevated in a second morning sample, further suggesting activation of TDO and kynase A. The AIP patients in this latter study were symptom-free, but exhibited elevated urinary levels of 5-ALA and PBG. This evidence concerns the gene TDO2 and autoimmune pancreatitis.