Because glucose metabolism provides a reliable measure of liver inflammation34, we were able to further rule out liver inflammation prior to therapy as a predisposing cause of CD4+ TEM≥21% hepatitis by estimating hepatic glucose uptake in patients who underwent 18F-fluoro-2-deoxy-d-glucose (18F-FDG) PET/CT studies as part of routine tumour staging shortly before starting immunotherapy (Fig. 3h). Here, CD4 is linked to Hepatitis.