title: Correlations between atazanavir C(trough )and hyperbilirubinemia: a case report.
abstract: BACKGROUND
  Hyperbilirubinemia is a common side effect of the antiretroviral agent atazanavir but is generally reversible upon discontinuation of treatment. We used therapeutic drug monitoring to investigate the occurrence of hyperbilirubinemia in a 49-year-old Hispanic man infected with HIV, following an overdose of ritonavir in ritonavir-boosted atazanavir therapy.
  
  
  METHODS
  A 49-year-old Hispanic man with HIV who had received several highly active antiretroviral therapy regimens over a number of years including atazanavir-containing regimens, was diagnosed with hyperbilirubinemia. An inappropriate doubling of ritonavir boosting resulted in a high atazanavir C(trough )and an initial rise in bilirubin plasma levels. Bilirubin levels later decreased, probably as a consequence of enzyme induction, while atazanavir plasma concentrations remained elevated.
  
  
  CONCLUSIONS
  This article describes an occurrence of hyperbilirubinemia in a man infected with HIV and supports the importance of therapeutic drug monitoring in investigations of hyperbilirubinemia among patients receiving antiretroviral agents. That the patient tolerated exceptionally high atazanavir levels further strengthens the tolerability profile of this drug.
authors.affiliation: HIV/AIDS Outpatient Clinic Infectious Disease Dept, Foundation "IRCCS Policlinico San Matteo Hospital", 27100 Pavia, Italy.
authors.forename: Alessia
authors.initials: A
authors.lastname: Uglietti
authors.forename: Stefano
authors.initials: S
authors.lastname: Novati
authors.forename: Roberto
authors.initials: R
authors.lastname: Gulminetti
authors.forename: Renato
authors.initials: R
authors.lastname: Maserati