Epidemiology of the infection by resistant Gram-positive microorganisms                    

EMILIA CERCENADO          

Resistance among Gram-positive microorganisms to classical and new antimicrobials is a therapeutic threat. In Spain, methicillin resistance among Staphylococcus aureus (25-30%) and coagulase-negative staphylococci (50-60%) seems to have stabilized in the last decade. Among enterococci, vancomycin resistance is less than 5%. Both linezolid and daptomycin, in general, show good activity against these microorganisms. However, the resistance rates of Staphylococcus epidermidis to linezolid (20.9%), and of Enterococcus faecium to daptomycin (10.5%) in isolates from intensive care units are a worrying.

Rev Esp Quimioter 2016; 29(Suppl. 1):6-9 [pdf]

Directed therapeutic approach to Staphylococcus aureus infections. Clinical aspects of prescription                     

FRANCISCO CARMONA-TORRE, MARTA RUA, JOSÉ LUIS DEL POZO          

 

Infections caused by Staphylococcus aureus have had classically an important impact in morbidity and mortality in the nosocomial and community scene. The description of methicillin resistance among nosocomial isolates of S. aureus and his widespread diffusion has become methicillin-resistant S. aureus (MRSA) in one of the most common causes of bacterial nosocomial infections. In the last years MRSA strains have also emergence in the community. This together with a progressive increase in resistance to antibiotics used classically has become vancomycin in the treatment of choice in most cases according to clinical guidelines.
As a result, a progressive rise in the minimum inhibitory concentration (MIC) to vancomycin has been reported. In this context strains with intermediate susceptibility to vancomycin (MIC 8-4 mg/L) and heteroresistance have been noted. These strains are associated with a higher risk of treatment failure when using vancomycin.
Among isolates of S. aureus susceptible to vancomycin there has been described stains with elevated MICs (≥1.5 mg/L). It is controversial if the presence of these strains has an impact on clinical outcome if treatment with vancomycin or β-lactams is prescribed.
The development of new antibiotics with activity against MRSA and exploring synergies offer a promising alternative to treatment with vancomycin.

Rev Esp Quimioter 2016; 29(Suppl. 1):15-20 [pdf]

Resistant gram-negative bacteria. Therapeutic approach and risk factors                     

PATRICIA SALGADO, FERNANDO GILSANZ, EMILIO MASEDA          

The rapid spread of multidrug-resistant bacteria has become a serious threat, especially in critical care units, thereby prolonging the hospital stay. Enterobacteriaceae have a high capacity to adapt to any environment. Plasmids are the reason behind their expansion. The choice of empiric therapy for intra-abdominal or urinary infections requires knowledge of the intrinsic microbiological variability of each hospital or critical care unit, as well as the source of infection, safety or antibi-tic toxicity, interaction with other drugs, the dosage regimen and the presence of risk factors. Carbapenems are the drug of choice in the case of suspected infection by ESBL-producing Enterobacteriaceae. The new ceftazidime/avibactam and ceftolozane/tazobactam drugs are opening up promising new horizons in the treatment of multidrug-resistant Enterobacteriaceae.

Rev Esp Quimioter 2016; 29(Suppl. 1):26-30 [pdf]

Multidrug-resistant tuberculosis: current epidemiology, therapeutic regimens, new drugs                     

CRISTINA GÓMEZ-AYERBE, MARÍA JESÚS VIVANCOS, SANTIAGO MORENO          

Multidrug and extensively resistant tuberculosis are especially severe forms of the disease for which no efficacious therapy exists in many cases. All the countries in the world have registered cases, although most of them are diagnosed in resource-limited countries from Asia, Africa and South America. For adequate treatment, first- and second-line antituberculosis drugs have to be judiciously used, but the development of new drugs with full activity, good tolerability and little toxicity is urgently needed. There are some drugs in development, some of which are already available through expanded-access programs.

Rev Esp Quimioter 2016; 29(Suppl. 1):35-38 [pdf]

Monotherapy vs. combined therapy in the treatment of multi-drug resistance gramnegative bacteria                     

FERNANDO MARTÍNEZ-SAGASTI, MIGUEL ÁNGEL GONZÁLEZ-GALLEGO, ALEJANDRO MONEO-GONZÁLEZ          

The increasing number of multidrug resistant gram negative bacteria, particularly in patients with risk factors, but in those who suffer community infections as well, is doing more and more difficult to choose the appropriate treatment. The most challenging cases are due to the production of extended-spectrum-β-lactamases (ESBL) and carbapenemases. This mini-review will discuss the adequacy of administering carbapenems when suspecting infections due to ESBL that could be modified after knowing the MIC of the isolated bacteria and the combined therapy in cases of carbapenemases, being particularly important to include a carbapenem and/or colistine at high dosages in this combination.

Rev Esp Quimioter 2016; 29(Suppl. 1):43-46 [pdf]