Drug-induced liver injury after liver transplantation.

: Drug-induced liver injury (DILI) is an adverse reaction to many drugs in common use that in a liver-transplant recipient may cause graft dysfunction and even lead to graft loss and the need for re-transplantation. However, several potential clinical scenarios, such as graft rejection and infection, can confound the diagnosis of suspected DILI in the setting of liver transplantation. This makes causal assessment of a new liver injury more uncertain and has traditionally precluded collection of bona fide cases of DILI affecting liver transplant patients in prospective DILI registries and cohorts. Although no studies have yet determined a greater susceptibility of the transplant patient to DILI, these subjects nevertheless present certain risk factors that can theoretically increase the risk of DILI. These include the fact that these patients are polymedicated, use drugs that are potentially hepatotoxic and can have coexisting hepatitis B or C, in addition to other factors found in non-transplant patients, such as genetic variants. Therefore, awareness of any potential hepatotoxic effect of drugs used in the liver transplant recipient and their possible implication in any case of liver dysfunction is crucial. In the present article we review the most common drugs used in liver transplant recipients from a liver safety perspective and address the main pitfalls in attributing causality in this clinical setting. We also affirm the need for further research and collaboration in this somewhat neglected topic in the field of DILI.