Voriconazole use and pharmacokinetics in combination with interferon-γ for refractory cryptococcal meningitis in a patient receiving low-dose ritonavir

We present a case of relapsing cryptococcal meningitis unresponsive to standard therapy. Voriconazole induction, including the utilization of voriconazole therapeutic drug monitoring in both serum and CSF, with transition to voriconazole plus interferon-gamma (IFN-γ) was successfully used in a patient receiving antiretroviral therapy with abacavir/lamivudine and lopinavir/ritonavir. Initial voriconazole levels at standard doses of 4 mg/kg twice daily intravenously were low when co-administered with lopinavir/ritonavir but increased to recommended therapeutic levels with an increase of the voriconazole dose to 7 mg/kg twice daily. This case highlights the utility of voriconazole therapeutic drug monitoring when prescribed concurrently with a ritonavir boosted protease inhibitor and the potential role of combination therapy with IFN-γ for refractory cryptococcal meningitis.