PTDM can be diagnosed only if hyperglycemia (again, fasting glucose ≥126 mg/dL or random glucose ≥200 mg/dL) persists for at least 45 d after LTx.2 PTDM is a multicausal disease, adding immunosuppressive drug use and donor factors138,143,144 to background characteristics shared with pre-LTx T2D (Figure 3), that is, dysfunctional insulin release and an impaired gut–pancreas incretin axis, as well as abdominal obesity, whenever present. This evidence concerns the gene INS and type 2 diabetes mellitus.