The increasing incidence of antimicrobial resistance (AMR) worldwide represents a serious threat in the management of sepsis. Due to resistance to the most common antimicrobials prescribed, multidrug-resistant (MDR) pathogens have been associated with delays in adequate antimicrobial therapy leading to significant increases in mortality, along with prolonged hospital length of stay (LOS) and increases in healthcare costs. In response to MDR infections and the delay of microbiological results, broad-spectrum antibiotics are frequently used in empirical antimicrobial therapy. This can contribute to the overuse and misuse of antibiotics, further promoting the development of resistance. Multiple measures have been suggested to combat AMR. This review will focus on describing the epidemiology and trends concerning MDR pathogens. Additionally, it will explore the crucial aspects of identifying patients susceptible to MDR infections and optimizing antimicrobial drug dosing, which are both pivotal considerations in the fight against AMR. Expert commentary: The increasing AMR in ICUs worldwide makes the empirical antibiotic therapy challenging in septic patients. An AMR surveillance program together with improvements in MDR identification based on patient risk stratification and molecular rapid diagnostic tools may further help tailoring antimicrobial therapies and avoid unnecessary broad-spectrum antibiotics. Continuous infusions of antibiotics, therapeutic drug monitoring (TDM)-based dosing regimens and combination therapy may contribute to optimizing antimicrobial therapy and limiting the emergence of resistance.

Background: Community-acquired intra-abdominal infections (CA-IAIs) exhibit significant clinical heterogeneity. However, most studies focusing on CA-IAIs do not stratify comparisons by infection site. Methods: This post hoc analysis of the prospective multicenter PERICOM cohort (13 French university hospitals, April 2018 to February 2019) included adult patients with CA-IAIs requiring surgical management. We compared clinical characteristics, microbiology, and outcomes between appendicular and non-appendicular sites. Secondary analyses assessed the impact of Enterococcus spp., Pseudomonas aeruginosa, or fungal documentation, and the theoretical coverage of empirical antibiotic regimens. Results: Of the 205 patients, 86 (42%) had appendicular and 119 (58%) had non-appendicular CA-IAIs. Appendicular CA-IAIs involved younger patients with fewer comorbidities and were followed by fewer major postoperative complications (Clavien-Dindo score ≥ 3: 10% versus 43%, p < 0.001) and no deaths (0% versus 12%, p < 0.001). Among 118 culture-positive patients, appendicular CA-IAIs showed higher rates of non-fermenting Gram-negative bacilli (25% versus 10%, p = 0.046) and anaerobes (53% versus 28%, p = 0.008) and were more often polymicrobial (76% versus 55%, p = 0.020). Conversely, Staphylococcus spp. (0% versus 9%, p = 0.036) and fungal co-infection (0% versus 12%, p = 0.010) were confined to non-appendicular CA-IAIs. Furthermore, Enterococcus spp. documentation (24/118, 20%) identified patients with greater admission severity and higher 28-day mortality (33% versus 2%, p < 0.001). Amoxicillin-clavulanic acid plus gentamicin covered the isolates of 92% of patients versus 61% for third-generation cephalosporin plus metronidazole (p < 0.001), a difference identical in both appendicular and non-appendicular sites. Conclusions: Appendicular and non-appendicular CA-IAIs appear to be distinct entities, supporting stratified management. Future guidelines should consider site-specific strategies, therapeutic individualization, and the integration of CA-IAI ecology.