Patients treated with aminoglycosides must be closely monitored because of the potential toxicity associated with their use. The target of aminoglycoside activity in the bacterial cell is the 30S ribosomal subunit. When the drug binds to the ribosome, the structure is unable to translate mRNA for protein production, leading to cell death. Aminoglycosides used for treatment of infections caused by Enterobacteriaceae or P. aeruginosa include gentamicin, amikacin, netilmicin, and tobramycin. In the United States, gentamicin is the most commonly used aminoglycoside.
Testing depends on the drugs most commonly used in the hospital.
However, gentamicin and either tobramycin or amikacin are typically on many commercial panels. Genes that encode for AMEs, the most common mechanisms of resistance, can be passed from organism to organism on plasmids and transposons. AMEs vary in their drug specificity, and many organisms can produce one or more AMEs. In addition, most AMEs inactivate more than one aminoglycoside. Therefore, resistance to one aminoglycoside may not predict resistance to the others.