Conceição, Jaime Manuel Guedes Morais daMatos, Carlos Adriano Albuquerque Andrade de2024-06-272024-06-272023-12-21http://hdl.handle.net/10400.1/25545Since the discovery of penicillin almost 100 years ago, antibiotics have revolutionized the treatment of many bacterial infections that were previously incurable and often lethal. Nonetheless, success of antibiotherapy is currently challenged by the emergence and dissemination of antimicrobial resistance, which occurs when changes in microorganisms render drugs ineffective. Misuse of antibiotics in humans, animals and the environment is often presented as one of the main causes for the selection of microorganisms that are increasingly resistant to currently available antimicrobial agents. Infections by resistant pathogens constitute one of the most important threats to global public health in the 21st century, being associated with high levels of morbidity and mortality, as well as a significant economic burden. Recent estimates suggest that, in 2019, approximately 1.27 million deaths worldwide were attributable to antibiotic-resistant bacterial infections. Among these, more than 141.000 deaths were attributable to three multidrug-resistant Gram-positive cocci, namely: methicillin-resistant Staphylococcus aureus (MRSA), vancomycin-resistant Staphylococcus aureus (VRSA) and vancomycin-resistant Enterococcus (VRE). These bacteria are responsible for a large percentage of nosocomial infections and constitute a priority for new antimicrobial drug development. This Dissertation aims to explore and analyze the current pharmacological approaches to the treatment of infections caused by the above bacteria. A description of these pathogens will be performed, addressing, among other relevant characteristics, their principal resistance mechanisms and the main clinical syndromes they can cause. Then, current antibiotherapeutic approaches used to manage each syndrome will be presented. The main pharmacological characteristics of each of the principal drugs mentioned in this context will be described, including its mechanism of action, posology and administration route, pharmacokinetic features, undesirable effects and main pharmacological interactions. Comprehension of existing antibiotherapy practices will contribute to the optimization of the use of available medicines and will help delineate the future of multi-drug resistant Gram-positive cocci anti-infective chemotherapy.engMethicillin-resistant staphylococcus aureusVancomycin-resistant staphylococcus aureusVancomycin-resistant enterococcusAntibiotherapyResistance mechanismsmaster thesis203497490