Tdm of Aminoglycoside Antibiotics and Vancomycin as an Indicator of the Quality of Medical Care: Results of the 7-Years Monitoring


      Therapeutic drug monitoring (TDM) of both aminoglycoside antibiotics (amikacin, gentamicin) and vancomycin is special method of clinical pharmacology using measurement of drug serum levels followed by interpretation and good cooperation with clinician. TDM helps in the dose adjustment of antibiotics according to the characteristics of a individual patient, in the lowering of toxicity and in the increasing of treatment cost-effectiveness.


      Vancomycin, gentamicin and amikacin levels were measured and antibiotics doses were adjusted on the basis of interdisciplinary cooperation between clinical pharmacologists and clinicians during seven years (2009-2015). Serum levels were analysed by immunoassay and LC-MS/MS method, dosage of antibiotics was changed using software MWPharm version 3.30. As an indicator of the quality assessment were used trough levels of gentamicin < 2.0 mg/L (or < 1.0 mg/L for once-daily since year 2013), amikacin < 10.0 mg/L (or < 5.0 mg/L for once-daily since year 2013) and vancomycin < 15.0 mg/L (< 20.0 mg/L since year 2013). The incidence of potentially toxic levels of the drugs was monitored monthly as an indicator of the quality of medical care and analysis of the causes of potentially toxic levels was done.


      Potentially toxic antibiotics levels were measured in 9 patients (1.1%) in year 2009 versus 5 patients (0.5 %) in year 2015 because the dose adjustment recommendations were not accepted by clinicians. The rate of potentially toxic levels after vancomycin initial dose in year 2015 was lower in comparison with report of the University of California San Francisco (3% versus 17%).


      Close contact between clinicians and clinical pharmacologists has led to a significantly lower incidence of the potentially toxic levels. Routine therapeutic drug monitoring of vancomycin and aminoglycoside antibiotics can reduce the risk of toxicity and improve the safety of health care.