Pharmacotherapy in a Multidisciplinary Paediatric Hospital: Polypharmacy and Drug–Drug Interaction Risk Illustrated with a Clinical Case

Nowadays, the problems caused by polypharmacy are recognised and widely discussed in the medical community. Multimorbidity, which is not uncommon in paediatric practice, comes with an increase in the number of prescriptions and necessitates an active search for tools to reduce the potential risk and frequency of adverse drug–drug interactions in paediatric patients.
The aim of the study was to use a clinical case to illustrate the need for monitoring, including laboratory monitoring of pharmacokinetic parameters, during concomitant therapy in paediatric practice.
Materials and methods: the study consisted in a retrospective analysis of the archived medical records of an 11-year-old child with nephrotic syndrome associated with a concomitant tuberculous process who had been receiving inpatient treatment with immunosuppressants at the Russian Children’s Clinical Hospital from May to July 2018.
Results: the prescription of cyclosporine for nephrotic syndrome entailed monitoring of plasma drug levels for potential pharmacokinetic interactions with the medicinal products used to treat the concomitant disease. The monitoring revealed an interaction between cyclosporine and rifampicin at the level of biotransformation. An adjustment of the concomitant therapy (discontinuation of rifampicin) allowed for achieving the target blood cyclosporine concentration, decreasing proteinuria and hypercholesterolemia, and increasing the blood total protein level in the child, which indicated the effectiveness of the ongoing treatment for the chief complaint.
Conclusions: the data obtained suggest that laboratory monitoring of pharmacokinetic parameters in paediatric polypharmacy can increase the effectiveness of therapy and prevent adverse reactions and irrational combination of medicinal products.

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