ACE and viral infectious disease: PTA can be caused by several conditions in renal transplant recipients, including renal allograft dysfunction, medications [immunosuppressive agents, angiotensin-converting enzyme (ACE) inhibitors, angiotensin II receptor antagonists, and antiviral and antimicrobial medications], viral infections, acute rejection, nutritional deficiency, and blood group ABO incompatibility (Reindl-Schwaighofer and Oberbauer, 2014).