Neopterin was used to quantify systemic inflammation since the IFN-γ pathway is a master checkpoint for many cytokines in the inflammatory response.57 However, neopterin is more representative of a Th1-type immune response and possibly more responsive to cellular infections such as viral infections, compared to bacterial infections.58 Other markers of systemic inflammation would increase the robustness of future studies. Here, IFNG is linked to viral infectious disease.