Case 2 also illustrates the potential severity of ICI-C, with rapidly progressive radiological appearances (Figure 2C–E) alongside gross hyperbilirubinaemia (peak value 453 μmol/L) and coagulopathy (1.4-fold increase in prothrombin time versus baseline) contributing to subarachnoid haemorrhage, and subsequently death. This evidence concerns the gene F2 and Hyperbilirubinemia.