Low-Frequency Ultrasound Enhances Bactericidal Activity of Antimicrobial Agents against Klebsiella pneumoniae Biofilm

Table 1

MICs and drug information of antimicrobial agents against K. pneumoniae.

Antimicrobial agent	MIC (μg/mL)	MIC interpretive criterion	Maximum concentration in plasma	Weight^a	Mechanism
Meropenem	0.0625	≤1 S	49 (39–58) μg/mL [12] (1 g intravenous infusion)	383.46	A bactericide for the bacterial breeding season
		2 I			Multiplication stage bactericide inhibition of cell wall synthesis by binding to penicillin-binding protein [12]
		≥4
Tigecycline	0.5	≤4 S	1.45(22%) μg/mL [13] (100 mg intravenous infusion)	585.64	Bacteriostatic agent
		8 I			Inhibition protein translation by binding to the 30S ribosomal subunit and blocking the entry of aminoacyl tRNA molecules into the A site of the ribosome [13]
		≥16 R
Fosfomycin	256	≤64 S	370 ± 61.9 μg/mL (8 g intravenous infusion) [14]	138.06	A bactericide for the bacterial breeding season
		128 I			Inhibition of peptidoglycan synthesis in the bacterial cell wall [14]
		≥256 R
Amikacin	1	≤16 S	90.6 (71.7–105.3) μg/mL (25 mg/kg intravenous infusion) [15]	585.60	Bactericide for rest period disruption and inhibition of protein synthesis by binding to the 30S ribosomal subunit [16]
		32 I
		≥64 R
Colistin	32	≤2 S	12.8 ± 6.2 μg/mL in sputum (4 million IU nebulized) [17]	1253.51	Bactericide for rest period
		>2 R			Surface active agent which penetrates and disrupts the bacterial cell membrane [17]

Concentrations are showed as mean ± SD, median (interquartile range), or mean (CV%). MIC interpretive criteria of meropenem, amikacin, tigecycline, and fosfomycin were based on CLSI. MIC interpretive criterion of colistin was based on EUCAST. ^aData from DrugBank.