Pseudomonas aeruginosa is associated with several human infections, mainly related to healthcare services. In the hospital, it is associated with resistance to several antibiotics, which poses a great challenge to therapy. However, one of the biggest challenges in treating P. aeruginosa infections is that related to biofilms. The complex structure of the P. aeruginosa biofilm contributes an additional factor to the pathogenicity of this microorganism, leading to therapeutic failure, in addition to escape from the immune system, and generating chronic infections that are difficult to eradicate. In this review, we address several molecular aspects of the pathogenicity of P. aeruginosa biofilms.

Staphylococcus aureus is a microorganism frequently associated with implant-related infections, owing to its ability to produce biofilms. These infections are difficult to treat because antimicrobials must cross the biofilm to effectively inhibit bacterial growth. Although some antibiotics can penetrate the biofilm and reduce the bacterial load, it is important to understand that the results of routine sensitivity tests are not always valid for interpreting the activity of different drugs. In this review, a broad discussion on the genes involved in biofilm formation, quorum sensing, and antimicrobial activity in monotherapy and combination therapy is presented that should benefit researchers engaged in optimizing the treatment of infections associated with S. aureus biofilms.

The aim of this study was to compare pharmacokinetic characteristics between intermittent infusion and continuous infusion of vancomycin for critically ill patients admitted to intensive care units. Intermittent therapy was administered for 60 minutes and prescribed as a loading dose of 30 mg/kg and continued with 15 mg/kg q12 h. Continuous infusion was prescribed as a loading dose of 30 mg/kg followed by 30 mg/kg on constant infusion pump. Blood samples from vancomycin intermittent infusion group were collected 1 h before third dose, 1 h, 8 h and 24 h after third dose infusion. Blood samples from vancomycin continuous infusion group were collected 1 h after loading dose, 12 h, 24 h, 36 h, and 48 h after continuous infusion initiation. Median serum concentration of continuous infusion group at 24-hour was 23.59 μg/mL [14.52–28.97], while of intermittent infusion group at 23-hour was 12.30 μg/mL [7.27–18.12] and on 25-hour was 17.58 μg/mL [12.5–22.5]. Medians AUC_24–48h were 357.2 mg.h/L and 530.2 mg.h/L for intermittent infusion and continuous infusion groups, respectively (p = 0.559). Vancomycin CI reached steady state earlier, which guaranteed therapeutic levels from the first day and made it possible to manage therapeutic drug monitoring faster.