Anton E Engelbrecht1, Lubbe Wiesner2, Jennifer Norman2, Helena Rabie3, Eric H Decloedt1. 1. Division of Clinical Pharmacology, Department of Medicine, Stellenbosch University, Cape Town, South Africa. 2. Division of Clinical Pharmacology, University of Cape Town, Cape Town, South Africa. 3. Division of Infectious Diseases, Department of Pediatrics and Child Health, Stellenbosch University, Cape Town, South Africa.
Abstract
INTRODUCTION: Antiretroviral therapeutic drug monitoring (TDM) is not routinely used in the management of human immunodeficiency virus, but may be useful in pediatric patients who are prone to altered pharmacokinetics. Data on the routine use of antiretroviral TDM in pediatrics are sparse especially data from sub-Saharan Africa. METHODS: We retrospectively reviewed the antiretroviral TDM indications at Tygerberg Children's Hospital, identified pediatric patients who had antiretroviral TDM requests from January 2012 until June 2017 and reviewed their clinical records. RESULTS: Fifty-nine patients were identified who presented with 64 clinical problems for which TDM was requested. TDM was requested for lopinavir, efavirenz and nevirapine in 83% (53/64), 14% (9/64) and 3% (2/64) of clinical problems, respectively. Lopinavir was mostly requested in patients when adherence measures did not correlate with the clinical picture, suspected non-adherence, lopinavir-rifampicin interactions and for neonatal safety monitoring. Efavirenz was requested when toxicity was suspected and nevirapine in patients receiving rifampicin. Lopinavir TDM confirmed non-adherence in 25% (4/16) of cases when adherence measures did not correlate with the clinical picture and in 43% (3/7) of cases when non-adherence was suspected by the clinician. Efavirenz TDM confirmed toxicity in 100% (6/6) of patients. CONCLUSIONS: Lopinavir TDM was mostly requested when adherence measures did not correlate with the clinical picture, when rifampicin was co-administered and for perinatal safety monitoring. Lopinavir TDM excluded pharmacokinetic reasons for failure in patients failing treatment when lopinavir dosing was supervised. Efavirenz TDM was requested for suspected toxicity with a 100% positive predictive value.
INTRODUCTION: Antiretroviral therapeutic drug monitoring (TDM) is not routinely used in the management of human immunodeficiency virus, but may be useful in pediatric patients who are prone to altered pharmacokinetics. Data on the routine use of antiretroviral TDM in pediatrics are sparse especially data from sub-Saharan Africa. METHODS: We retrospectively reviewed the antiretroviral TDM indications at Tygerberg Children's Hospital, identified pediatric patients who had antiretroviral TDM requests from January 2012 until June 2017 and reviewed their clinical records. RESULTS: Fifty-nine patients were identified who presented with 64 clinical problems for which TDM was requested. TDM was requested for lopinavir, efavirenz and nevirapine in 83% (53/64), 14% (9/64) and 3% (2/64) of clinical problems, respectively. Lopinavir was mostly requested in patients when adherence measures did not correlate with the clinical picture, suspected non-adherence, lopinavir-rifampicin interactions and for neonatal safety monitoring. Efavirenz was requested when toxicity was suspected and nevirapine in patients receiving rifampicin. Lopinavir TDM confirmed non-adherence in 25% (4/16) of cases when adherence measures did not correlate with the clinical picture and in 43% (3/7) of cases when non-adherence was suspected by the clinician. Efavirenz TDM confirmed toxicity in 100% (6/6) of patients. CONCLUSIONS:Lopinavir TDM was mostly requested when adherence measures did not correlate with the clinical picture, when rifampicin was co-administered and for perinatal safety monitoring. Lopinavir TDM excluded pharmacokinetic reasons for failure in patients failing treatment when lopinavir dosing was supervised. Efavirenz TDM was requested for suspected toxicity with a 100% positive predictive value.