Rev Esp Quimioter 2016, 29(4):202-205

Antimicrobial susceptibility of Gram-negative bacilli of community acquired intra-abdominal infections in a hospital at Buenos Aires, Argentina                     

LAURA MORGANTI, EZEQUIEL CÓRDOVA, ELSA CASSINI, NORA GÓMEZ, LAURA LÓPEZ MORAL, MARCELA BADÍA, CLAUDIA RODRÍGUEZ          

Introduction. Community acquired complicated intra-abdominal infections (cIAI) are a common condition. Few data are available about the level of antimicrobial resistance of Gram-negative bacteria isolated from community acquired cIAIs in Argentina.
Methods. Retrospective-prospective observational study (March 2010 to February 2012). Gram-negative bacteria antimicrobial susceptibility of isolates from community acquired cIAIs were evaluated.
Results. During this period, a total of 85 patients were included and 138 pathogens were collected. Male sex: 58%. Median age: 33. Monomicrobial cultures were obtained in 49% of the cases. Ninety (65%) corresponded to Gram-negative organisms, and 48 (38%) to Gram-positive cocci. Gram-negative organisms most frequently observed were: Escherichia coli 76%, Klebsiella pneumoniae 8%, Pseudomonas aeruginosa 7% and Enterobacter spp. 6%. E. coli and K. pneumoniae showed a high percentage of strains resistance to ciprofloxacin of 37% and 29%, respectively. Similarly, resistance to ampicillin/sulbactam was observed in a 16% of the E. coli isolates. The prevalence of multiresistant Gram-negative organisms was 38%.
Conclusions. A high level of resistance to antimicrobials was observed in community acquired cIAIs, mainly to ciprofloxacin and ampicillin/sulbactam two of the most used antimicrobial for empirically treatment of cIAIs in our country. In addition a significant proportion of multiresistant Gram-negative organisms were identified.

Rev Esp Quimioter 2016; 29(4):202-205 [pdf]

Rev Esp Quimioter 2016, 29(Suppl. 1):31-34

Approach to directed therapy after knowledge of the isolate: carbapenemase-producing Enterobacteriaceae, multidrug-resistant Pseudomonas aeruginosa and carbapenem-resistant Acinetobacter baumannii                     

JOSÉ ANTONIO MARTÍNEZ          

Directed treatment of infections due to multidrug-resistant Gram-negative bacilli is a difficult task, since it requires the use of a limited number of antibiotics that are often more toxic and possibly less efficacious than β-lactams and fluoroquinolones. Furthermore, there are very few controlled trials informing on the relative efficacy of different therapeutic strategies.  As a general rule, it is recommended to use at least two active drugs or a combination with proven synergistic activity in vitro, because several observational studies have associated this practice with better outcomes and as a measure to potentially curb the emergence of further resistance. It is already available a new cephalosporin active against most strains of Pseudomonas aeruginosa resistant to ceftazidime due to derepression of ampC and in the near future an effective inhibitor of class A, class C and OXA-48 will be available which combined with ceftazidime is expected to mean a significant addition to the armamentarium against Gram-negative bacilli with these resistance determinants.

Rev Esp Quimioter 2016; 29(Suppl. 1):31-34 [pdf]

Rev Esp Quimioter 2016, 29(6):308-317

Darunavir/cobicistat monotherapy. Experience in a tertiary hospital                     

LUCIA YUNQUERA-ROMERO, ROCÍO ASENSI-DÍEZ, JUAN CARLOS DEL RIO-VALENCIA, ISABEL MUÑOZ-CASTILLO, MANUEL ÁNGEL CASTAÑO-CARRACEDO          

Introduction. Ritonavir-boosted protease inhibitor (IP/r) monotherapy: darunavir/ritonavir (DRV/r) or lopinavir/ritonavir (LPV/r) monotherapy is only provided in the major treatment guidelines in pretreated patients to prevent toxicity associated with nucleoside/nucleotide reverse transcriptase inhibitor (NRTI), reduce costs and simplify antiretroviral treatment. To start IP/r monotherapy, according to GESIDA guidelines 2016, patients need to meet the following criteria: absence of chronic hepatitis B, plasma viral load <50 copies/ mL for at least 6 months and absence of protease inhibitors mutations or previous virologic failures to IP/r. Currently, there are no studies that evaluate the efficacy and safety of darunavir/cobicistat (DRV/COBI) monotherapy.
Methods. This prospective study analyzed pretreated HIV patients with DRV/r monotherapy that were switched to DRV/COBI monotherapy. The aim of the study is to describe the effectiveness and safety of the DRV/COBI monotherapy.
Results. Seventy-eight patients were evaluated. Patients had a median of 31.29 months of DRV/r monotherapy before DRV/COBI monotherapy. Nine of the 78 patients developed “blips” (plasma viral load: 50-200 copies/ml) and four patients had plasma viral load ≥200 copies/mL. An 83.3% (65/78) of the patients remained with undetectable plasma viral load. As for safety, there were no significant differences in lipid profile, liver function (transaminases) and renal function between DRV/r and DRV/COBI monotherapy.
Conclusions. DRV/COBI monotherapy seems to be effective and safe (lipid profile, liver and kidney function). However, it will be necessary to design specific studies comparing DRV/r vs DRV/COBI monotherapy to confirm these results.

Rev Esp Quimioter 2016; 29(6):308-317  [pdf]

Rev Esp Quimioter 2017, 30(2):84-89

Antibacterial effect of sevoflurane and isoflurane                     

MARÍA MARTÍNEZ-SERRANO, MANUEL GERÓNIMO-PARDO, ÁNGEL MARTÍNEZ-MONSALVE, MARÍA DOLORES CRESPO-SÁNCHEZ           

Introduction. Multidrug resistant bacteria are increasing worldwide and therapeutic options are limited. Some anaesthetics have shown antibacterial activity before. In this study, we have investigated the antibacterial effect of the halogenated anaesthetic agents sevoflurane and isoflurane against a range of resistant pathogens.
Methods. Two experiments were conducted. In the first, bacterial suspensions of both ATCC and resistant strains of Staphylococcus aureus, Escherichia coli and Pseudomonas aeruginosa were exposed to liquid sevoflurane and isoflurane during 15, 30 and 60 minutes. In the second experiment clinical resistant strains of E. coli, Klebsiella pneumoniae, Enterobacter cloacae, P. aeruginosa, Acinetobacter baumannii, S. aureus, and Enterococcus faecium were studied. Previously inoculated agar plates were irrigated with the halogenated anaesthetic agents and these were left to evaporate before the plates were incubated. In both experiments colony forming units were counted in resultant plates.
Results. In the first experiment, isoflurane showed faster and higher antimicrobial effect than sevoflurane against all the strains studied. Gram-negative organisms were more susceptible. In the second experiment, E. faecium was found to be resistant to both halogenated agents; only isoflurane showed statistically significant activity against the rest of the strains studied.
Conclusions. Both halogenated agents, but particularly isoflurane, showed in vitro antibacterial activity against pathogens resistant to conventional antibiotics. Further investigation is required to determine whether or not they also exhibit this property in vivo. This might then allow these agents to be considered as rescue treatment against multidrug resistant patho-gens, including a topical use in infected wounds.

Rev Esp Quimioter 2017; 30(2):84-89  [pdf]

Rev Esp Quimioter 2015:28(3):132-138

A practice-based observational study on the use of micafungin in Surgical Critical Care Units                                 
 


EMILIO MASEDA, CARLOS A. GARCÍA-BERNEDO, ISABEL FRÍAS, JOSÉ-ALEJANDRO NAVARRO, JESÚS RICO, REYES IRANZO, JUAN-JOSÉ GRANIZO, MARÍA-JOSÉ VILLAGRÁN, ENRIC SAMSÓ, FERNANDO GILSANZ ON BEHALF OF THE MYCREA STUDY GROUP      
        

 

Introduction. Echinocandins are first-line therapy in critically ill patients with invasive Candida infection (ICI). This study describes our experience with micafungin at Surgical Critical Care Units (SCCUs).
Methods. A multicenter, observational, retrospective study was performed (12 SCCUs) by reviewing all adult patients receiving 100 mg/24h micafungin for ≥72h during ad-mission (April 2011-July 2013). Patients were divided by ICI category (possible, probable + proven), 24h-SOFA (<7, ≥7) and outcome.
Results. 72 patients were included (29 possible, 13 probable, 30 proven ICI). Forty patients (55.6%) presented SOFA ≥7. Up to 78.0% patients were admitted after urgent surgery (64.3% with SOFA <7 vs. 90.3% with SOFA ≥7, p=0.016), and 84.7% presented septic shock. In 66.7% the site of infection was intraabdominal. Forty-nine isolates were recovered (51.0% C. albicans). Treatment was empirical (59.7%), microbiologically directed (19.4%), rescue therapy (15.3%), or anticipated therapy and prophylaxis (2.8% each). Empirical treatment was more frequent (p<0.001) in possible versus probable + proven ICI (86.2% vs. 41.9%). Treatment (median) was longer (p=0.002) in probable + proven versus possible ICI (13.0 vs. 8.0 days). Favorable response was 86.1%, without differences by group. Age, blood Candida isolation, rescue therapy, final MELD value and %MELD variation were significantly higher in patients with non-favorable response. In the multivariate analysis (R2=0.246, p<0.001) non-favorable response was associated with positive %MELD variations (OR=15.445, 95%CI= 2.529-94.308, p=0.003) and blood Candida isolation (OR=11.409, 95%CI=1.843-70.634, p=0.009).
Conclusion. High favorable response was obtained, with blood Candida isolation associated with non-favorable response, in this series with high percentage of patients with intraabdominal ICI, septic shock and microbiological criteria for ICI.

Rev Esp Quimioter 2015:28(3):132-138 [pdf]

Rev Esp Quimioter 2015:28(Suppl. 1):16-18

Usefulness of PK/PD parameters of antimicrobials in the treatment of complex and extremely-resistant infections     

                        
JUAN PABLO HORCAJADA              

Complex or difficult to treat infections should benefit from antimicrobial PK/PD data in each specific situation. In the case of multidrug resistant gram negative infections the optimized use of colistin needs the using of PK/PD indexes. Likewise, in infections of inaccessible sources, PK/PD concepts play a key role in choosing the best antimicrobial and dosage. An example would be the potential role of linezolid in CNS infections. Among fungal infections, symptomatic candiduria by fluconazole-resistant strains are a therapeutic challenge. In this context micafungin could be a good alternative, again based on PK/PD concepts.

Rev Esp Quimioter 2015:28(Suppl. 1):16-18 [pdf]

Rev Esp Quimioter 2015:28(6):282-288

Potential antimicrobial drug interactions in clinical practice: consequences of polypharmacy and multidrug resistance     

                        
CRISTINA MARTÍNEZ-MÚGICA              

Background. Polypharmacy is a growing problem nowadays, which can increase the risk of potential drug interactions, and result in a loss of effectiveness. This is particularly relevant to the antiinfective therapy, especially when infection is produced by resistant bacteria, because therapeutic options are limited and interactions can cause treatment failure.
Methods. All antimicrobial prescriptions were retrospectively reviewed during a week in the Pharmacy Department, in order to detect potential drug-interactions and analysing their clinical significance. A total of 314 antimicrobial prescriptions from 151 patients were checked.
Results. There was at least one potential interaction detected in 40% of patients, being more frequent and severe in those infected with multidrug-resistant microorganisms. Drugs most commonly involved were quinolones, azoles, linezolid and vancomycin.
Conclusions. Potential drug interactions with antimicrobial agents are a frequent problem that can result in a loss of effectiveness. This is why they should be detected and avoided when possible, in order to optimize antimicrobial therapy, especially in case of multidrug resistant infections.

Rev Esp Quimioter 2015;28(6):282-288 [pdf]

Rev Esp Quimioter 2016, 29(2):86-90

Surveillance of antimicrobial susceptibility of Escherichia coli producing urinary tract infections in Galicia (Spain)     

                        

MERCEDES TREVIÑO, ISABEL LOSADA, BEGOÑA FERNÁNDEZ-PÉREZ, AMPARO COIRA, MARÍA F. PEÑA-RODRÍGUEZ, XURXO HERVADA Y GRUPO DE ESTUDIO DE LA SOGAMIC PARA EL ESTUDIO DE RESISTENCIAS EN GALICIA             


Introduction. Escherichia coli is the microorganism responsible for most of the community-acquired urinary tract infections (UTI). Our purpose was to determine the susceptibility of E. coli associated with UTI in Galicia and consider the most appropriate antibiotics for empirical treatment.
Methods. Retrospective study during the period 2011- 2012 of the isolation of E. coli in urine samples from almost all the Galician population. Demographic variables, minimum inhibitory concentration, and reading data were collected: amoxicillin-clavulanate, cefotaxime, gentamicin, amikacin, ciprofloxacin, cotrimoxazole, nitrofurantoin and fosfomycin. The identification and susceptibility studies were mainly conducted by automated systems. The interpretation of the results was performed according to CLSI criteria.
Results. During the study period 55,046 E. coli were isolated in UTI. The percentages of resistance were: cotrimoxazole, 30%; ciprofloxacin, 33%; amoxicillin-clavulanate, 23% and 10% for 3rd generation cephalosporins. Fosfomycin and nitrofurantoin showed the highest activity with more than 96% of susceptibility in our study. The linear trend of resistance regarding age was statistically significant (p <0.0001) as it was regarding males (p <0.00001) for all antibiotics.
Conclusions. In Galicia, the most active antibiotics against E. coli associated with UTI are fosfomycin and nitrofurantoin so they should be considered as empirical treatment of choice by the community-acquired UTI not complicated by E. coli.

Rev Esp Quimioter 2016; 29(2):86-90 [pdf]

Rev Esp Quimioter 2016, 29(4):206-213

Changes in the epidemiology of Clostridium difficile infection during 2005-2014 in Salamanca, Spain                    

OLAIA CORES-CALVO, ENRIQUE GARCÍA-SÁNCHEZ, LUIS FÉLIX VALERO-JUAN, JOSÉ ELÍAS GARCÍA-SÁNCHEZ, MARÍA INMACULADA GARCÍA-GARCÍA          

Background. To know the most relevant epidemiological features of Clostridium difficile infection (CDI) between 2005- 2014 in the province of Salamanca (Spain).
Methods. Descriptive cross-sectional study carried out through review of the clinical microbiologic records at Complejo Asistencial Universitario de Salamanca. Detection was performed according to standard methodology.
Results. 2.6% of stool samples analyzed for detection of C. difficile toxins (9,103) were positive. The average prevalence was 6.8 cases per 100,000 people per year. The mean age was 65 ± 21.4 years and the median 70 years. 59% of cases occurred in patients over 64 years, with an average prevalence of 16.5 (4 times higher than the 15-64 group). Most cases (86.4%) occurred in hospitalized patients, and the group of over 64 had the highest percentage of hospital CDI, with 55%.
Conclusions. A significant increase in the number of requests and in the prevalence of CDI over the decade studied is observed, and prevalence rates were significantly lower than those of other studies. The percentage of CDI increased significantly in both inpatient and community. Age and hospitaliza-tion were risk factors for developing CDI. After the introduc-ion of a molecular detection technique in 2014, the prevalence increased, being 2.5 times higher than 2013.

Rev Esp Quimioter 2016; 29(4):206-213 [pdf]

Rev Esp Quimioter 2016, 29(Suppl. 1):35-38

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]