Table 1.

Clinical scenarios involving both DILI/HDS and AIH.

Scenario	Characteristics
DILI/HDS on top of AIH	◾Can be misinterpreted as an aggressive course of AIH if the causative agent is not identified ◾In most cases of AIH, IgG/gammaglobulins parallel the increase of transaminases; this helps to differentiate AIH from DILI/HDS
Drug-induced AIH	◾Drug intake triggering the chronic course of AIH is an unlikely scenario ◾Coincidence of drug intake and pre-existing AIH seems more likely
Second episode of DILI mimics relapsing course of AIH	◾According to current studies, this scenario is rare ◾Repeated drug history is helpful to identify the causative agents
Chronic DILI mimics AIH	◾Chronic DILI/HDS through sustained intake of the causative drug is possible ◾Underreporting (especially of analgetics, HDS, etc.) hampers identification of the causative drug ◾However, the presence of cirrhosis favours the diagnosis of AIH and makes DILI/HDS less likely
DILI/HDS with characteristics of AIH (“autoimmune(-like)” DILI/HDS, “immune-mediated” DILI/HDS)	◾The terms are used for DILI/HDS cases characterized by the presence of autoantibodies and/or infiltration of the liver by immune competent cells ◾However, most of the autoantibodies (e.g., ANA and anti-SMA) are not disease-specific ◾Demarcation of “autoimmune(-like)” DILI/HDS from AIH is difficult ◾Features supporting the diagnosis of AIH are a relapse of transaminases and IgG/gammaglobulins after steroid withdrawal and a chronic, fluctuating course ◾Close monitoring of transaminases (weekly for the first 1–2 months, every 2–3 weeks for the next 2–3 months, every 3 months for the next 1–2 years) and IgG/gammaglobulins is necessary to confirm the correct diagnosis

Abbreviations: DILI/HDS: Herbal and Dietary Supplements; AIH: Autoimmune Hepatitis; ANA: anti-nuclear antibodies; SMA smooth muscle antigen.