Rev Esp Quimioter 2011:24(1):13-24

Role of daptomycin in the empirical and directed therapy of infections caused by Gram-positive bacteria in the critically ill patient

J. GARNACHO-MONTERO, R. AMAYA-VILLAR, M. L. GÓMEZ-GRANDE, V. JEREZ, L. LORENTE-RAMOS, A. LOZA, A. MARTÍNEZ, J. C. POZO, R. SIERRA, J. POMARES, M. V. DE LA TORRE, C. ORTIZ   

 

Infections caused by Gram-positive bacteria are a serious problem and is associated with high mortality. Among them, we should highlight those caused by methicillin-resistant Staphylococcus aureus (MRSA). Primary bacteremia, catheter-related bloodstream infections and constitute the main presentations. Vancomycin has traditionally been the treatment of choice for these infections, but its activity is not satisfactory especially in cases of MRSA with minimum inhibitory concentration (MIC) > 1 mg/L. Daptomycin is a lipopeptide antibiotic active against Gram-positive bacteria including MRSA and glycopeptide-resistant Enterococcus spp.It is worth mentioning that daptomycin is rapidly bactericidal against methicillin-sensitive S. aureus, more potent than vancomycin and at least as active as isoxazole penicillins. This article discusses the role of this antibiotic in the empirical treatment of infections and directed by Gram-positive bacteria affecting critically ill patients.    

 
Rev Esp Quimioter 2011:24(1):13-24 [pdf]

Rev Esp Quimioter 2011:24(3):131-135

Rapid identification and susceptibility testing of Gram-positive cocci in BacT/ALERT blood cultures by direct inoculation into the Vitek 2 system       

A. BARREALES, M. LARA, I. HERNÁNDEZ, Ó. DÍEZ           

 

Introduction: To provide the clinician with early information about blood culture results allows a better prognosis and a reduced mortality rate of the patient with sepsis. In order to contribute to this aim, we performed a study for the identification and susceptibility profiling of positive blood cultures by direct inoculation into the automated Vitek 2 system.
Materials and Methods: Blood cultures of 57 patients with monomicrobial bacteriaemia due to gram-positive cocci
were evaluated. Addition of saponin to the fluid from blood culture bottles was performed prior to the inoculation of Vitek 2 system cards. The same samples were also examined with the standard method starting from agar plate grown subcultures.
Results: Comparison between the results obtained with the standard method and the direct method revealed that 82% of the samples were correctly identified and that 97% of the isolates showed a concordant antimicrobial susceptibility profile for all drugs tested. Compared to the standard method, the very major error rate of the direct method was just 0.5%, the major error rate was 0.5%, and the minor error rate was 2%.
Conclusion: These data suggest that addition of saponin to the fluid from blood culture bottles of the BacT/ALERT® 3D before inoculation of the appropriate Vitek 2 cards leads to the rapid and reliable identification and susceptibility profiling of gram-positive cocci in blood samples. Compared to the standard method, the direct method would reduce turnaround time by at least 24 hours.

 
Rev Esp Quimioter 2011:24(3):131-135 [pdf]

Rev Esp Quimioter 2012:25(1):4-9

Invasive fungal infection in critically ill patient: role of micafungin                

M. NIETO, E. ESCUDERO                         

The invasive fungal infections (IFIs) have increased in critically ill patients in recent years and are a serious complication that determine the evolution and prognosis of critically ill patients, especially invasive candidiasis (IC) and candidemia. Fortunately, treatment options for these infections have increased and there is a large arsenal of antifungal agents. This review of the literature, using PubMed and Cochrane databases, assesses the situation of the IFIs in critically ill patients and discusses the role of micafungin in this context. The broader spectrum of this candin, which gets the antifungal effect with lower MICs and that translates into greater clinical efficacy with a lower rate of adverse effects and easier to use, with proven cost-effectiveness compared with other antifungal, position micafungin as a useful therapeutic option for the management of invasive candidiasis / candidemia in critically ill patients. 

 
Rev Esp Quimioter 2012:25(1):4-9 [pdf]

Rev Esp Quimioter 2012:25(2):139-146

Antibiotic prescribing to the paediatric population of Castilla y León in the last decade: trends, seasonal fluctuations and geographical differences            

M. E. VÁZQUEZ, J. M. EIROS, F. MARTÍN, S. GARCÍA, R. M. BACHILLER, M. J. VÁZQUEZ                                                                   

 
Introduction. The development of antibiotic resistance is a danger to the health of the population, especially for children, due to low antimicrobial arsenal available to them.
Material and methods. We performed a retrospective observational study referred to the prescriptions of systemic antibiotic in the paediatric population of Castilla y León in the years 2001 to 2010.
Results. The total use of antibiotics outside hospitals is around to 20.7 DID (defined daily dose per 1,000 inhabitants per day). There are two different phases: the first from 2001 to 2007 where there is an increase of consumption, with a peak of 25 DID in 2003, following a phase of decline, with a minimum of 18 DID in 2010. Broad-spectrum penicillins are the most used. We also observe changes in prescription trends. It has a clear seasonal prescription profile related to acute respiratory infections (ARI) of winter, stands in February. The use of antibiotics varies substantially between different Health Areas.
Conclusions. We observed a decrease in antibiotic prescription to children in the last three years. Changes in the prescription profile for amoxicillin and at the expense of greater spectrum antibacterial antibiotics indicate a better match to therapeutic guidelines in recent years. The variability found in different Health Areas suggests the need for improvement in the rational use of antibiotic, at least to some.
 

Rev Esp Quimioter 2012:25(2):139-146 [pdf]

Rev Esp Quimioter 2012:25(4):266-268

Susceptibility to fluconazole of clinical interest yeasts: new breakpoints                     

L. GARCÍA-AGUDO, P. GARCÍA-MARTOS, P. MARÍN-CASANOVA, M. RODRÍGUEZ-IGLESIAS                                                  
                              
 
 

 

Introduction. Recently, Pfaller et al (Drug Resist Update 2010; 13:180-95), have proposed new breakpoints for determining the in vitro susceptibility to fluconazole of Candida albicans, C. parapsilosis and C. tropicalis. The aim of this study was to establish the variations in sensitivity of these species applying these breakpoints, in relation to those of the Clinical and Laboratory Standards Institute (CLSI).
Methods. We analyzed 112 strains of Candida: 49 C. albicans, 40 C. parapsilosis and 23 C. tropicalis. Susceptibility to fluconazole was performed by the method Sensititre YeastOne. The breakpoints used to determine the minimum inhibitory concentration (MIC) were identified by CLSI and the ones proposed by Pfaller et al.
Results. According to the CLSI criteria, all isolates were susceptible to fluconazole. MIC50 and MIC90 were 0.5 mg/L and 2 mg/L for C. albicans and C. parapsilosis, 0.5 mg/L and 1 mg/L for C. tropicalis. With the new criteria, 109 (97%) strains were susceptible. Variations were seen in C. albicans, with 3 strains (6%) susceptible dose-dependent.
Conclusions. When applying the breakpoints recommended by Pfaller et al, and EUCAST, the number of fluconazole- susceptible strains decreased according to the CLSI criteria, especially C. albicans.  

Rev Esp Quimioter 2012:25(4):266-268 [pdf]

Rev Esp Quimioter 2009:22(4):224-227

Colonial architecture and growth dynamics of Staphylococcus aureus resistant to methicillin

F. GÓMEZ-AGUDO, M. L. GÓMEZ-LUS, M. T. CORCUERA, L. ALOU, M. J. ALONSO, D. SEVILLANO, D. VAL, A. PALMEIRO, N. IGLESIAS, J. PRIETO

 

The aim of the study was to explore the structure and growth dynamics of Staphylococcus aureus resistant to methicillin (MRSA) colonies using semithin sections visualized by light microscope. One S. aureus susceptible to methicillin (MSSA) and one MRSA clinical strains were studied. Colonies in agar plates were embedded in epoxy resin after each incubation period (24 h and 48 h) at 37ºC. Semithin sections of 0.5µm were stained with toluidine blue and visualized by light microscope. Microscopically, no structural differences were observed between SASM and SARM colonies but differences were observed in both strains between 24 and 48 h incubation periods. Colonies showed two layers clearly differentiated at24 h independently of the resistance to methicillin: (A) one basal layer with high density of population in contact with culture media, and (B) one superficial layer with a lower density of population. Colonies showed four layers at 48 h:(A) one basal layer with high density of population; (B) one clear layer constituted by very degraded bacterial remains in which can be observed cocci dispersed with their dyeing properties; (C) one mixed layer constituted by viable bacteria and little degraded bacterial remains (D) one superficial layer with a lower density of population than basal layer. Colonial architecture is a complex and time-dependent process.

 
Rev Esp Quimioter 2009:22(4):224-227 [pdf]

Rev Esp Quimioter 2010:23(3):109-114

Treatment of human infections caused by Bartonella spp. 

L. PÉREZ-MARTÍNEZ, J. R. BLANCO, J. A. OTEO 

 

Infections by Bartonella spp. include a wide spectrum of emerging and re-emerging infectious diseases.There is not a universal therapy for this infection, therefore treatment should be chosen individually. The aim of this review is to update the therapeutics aspects of this kind of infections.

 
Rev Esp Quimioter 2010:23(3):109-114 [pdf]

Rev Esp Quimioter 2011:24(1):25-31

Predictive factors of 2009 H1N1 virus infection in patients with influenza syndrome

A. SUPERVÍA, F. DEL BAÑO, G. MALDONADO, O. PALLÀS, A. AGUIRRE, C. VILAPLANA, J. P. HORCAJADA, M. T. MARTÍNEZ-IZQUIERDO    

 

Introduction: Polymerase chain reaction (PCR) testing isone of the better techniques for viral detection in nasopharyngeal swabs. The objective of this study was to assess the percentage of positive swabs and to determine whether there were differences according to PCR positivity.
Material and Methods: A retrospective study of 362 patients with flu syndrome attended at the Emergency Department between July 15 and December 15, 2009, in whom PCR of nasopharyngeal swabs for the detection of H1N1 2009 influenza virus was performed.  Those cases in which swab testing was adequately requested were identified, and patients were divided into two groups according to positive or negative results for H1N1 2009 influenza virus.
Results: Nasopharyngeal swab was inadequately ordered in 87. In the remaining 275 patients, PCR was positive in 141. Patients with positive nasopharyngeal swabs were younger (mean [SD] age 36.1 [15] vs42.3 [18] years, P= 0.002), had lower white blood cell, neutrophil and lymphocyte counts, lower serum concentrations of C-reactive protein (5.15 [5] vs 10.5[12] mg/dL, P= 0.036) and lower incidence of radiological infiltrates (20.5% vs 33%, P= 0.036). In the logistic regression analysis, age, serum C-reactive protein levels, and lymphocyte count were independently associated with a positive nasopharyngeal swab.
Conclusions: About 50% of patients with flu syndrome had positive nasopharyngeal swabs for H1N1 2009 influenza virus. Age, C-reactive protein, and lymphocyte count were independent predictors of positivity.    


Rev Esp Quimioter 2011:24(1):25-31 [pdf]

Rev Esp Quimioter 2011:24(3):136-142

Which is the best empirical treatment in patients with urethritis?      

M. A. ORELLANA, M. L. GÓMEZ–LUS            

 

Objective. To know the best empirical treatment of urethritis in patients at the City Center of Madrid.
Methods. 2.021 urethral exudates were analyzed in men between January 2003-December 2007. In addition to the traditional cultures, it was determined the presence of Chlamydia trachomatis, Ureaplasma urealyticum, Mycoplasma hominis, Trichomonas vaginalis and Herpes simplex. The susceptibility of N.gonorrhoeae and Haemophilus spp was performed by disk diffusion method and U. urealyticum by Mycoplasma IST.
Results. The percentage of positive samples was: 30.6%. The most frequently isolated microorganisms were: U. urealyticum 9.9%, N. gonorrhoeae 7.4%, C. trachomatis 5.1% and Haemophilus spp 3.8%. The resistance of N. gonorrhoeae in the first period was: penicillin 11.8%, tetracycline 5.9%, ciprofloxacin 8.8% and presence of betalactamase 11.8%. In the second period: penicillin 9.7%, amoxicillin/clavulanic acid 1.4%, tetracycline 8.3%, ciprofloxacin 23.6% and presence of betalactamase 10.5%. Resistance to ciprofloxacin in non-MSM (men having sex with men) was 20% and in MSM 56.2% (p <0.05). Resistance of Haemophilus spp in the first period was: 38.2% ampicillin, amoxicillin/clavulanic acid 8.8%, clarithromycin 35.3%, cotrimoxazole 64.7%, cefuroxime 5.9%, ciprofloxacin 8.8%, tetracycline 12.1% and presence of betalactamase 26.5%. In the second period: presence of betalactamase 41.9%, ampicillin 53.1%, amoxicillin/clavulanic acid 9.4%, cefuroxime 9.4%, clarithromycin 18.7%, tetracycline 34.4%, ciprofloxacin 15.6%, and cotrimoxazole 68.7%. Resistance of U. urealyticum was: ciprofloxacin 80.7%, ofloxacin 32.4%, erythromycin 17.5%, azithromycin 9.6%, tetracycline 3.5% and doxycycline 0.8%.
Conclusions. N. gonorrhoeae showed a level of resistance to tetracycline and ciprofloxacin higher in the second period, being significant for ciprofloxacin (p<0.05). Quinolone resistance was higher in MSM. Haemophilus spp showed a level of resistance to ampicillin, ciprofloxacin and tetracycline higher in the second period, being significant for tetracycline (p <0.05). U.urealyticum showed high level of resistance to ciprofloxacin (80.7%) and ofloxacin (32.4%) and low level of resistance to doxycycline (0.8%) and tetracycline (3.5%).

 

 
Rev Esp Quimioter 2011:24(3):136-142 [pdf]

Rev Esp Quimioter 2012:25(1):10-16

Macrolides and staphylococcal biofilms                

J. PARRA-RUIZ, C. VIDAILLAC, M. J. RYBAK                            

Medical device-associated infections represent a growing problem with limited or no therapeutic options beyond implant removal. Bacterial biofilm is the major and the final determinant of the poor prognosis of these difficult-to-treat infections. Due to the high antimicrobial resistance level of bacteria organized in biofilms, combination therapy is most often recommended, and macrolides may represent antibiotics of choice. Their anti-biofilm activity has been successfully used in-vitro and in-vivo against biofilm-associated infections caused by Pseudomonas aeruginosa and other Gram-negative bacilli. However there is only little data regarding their clinical interest against infections involving staphylococcal biofilms. Despite controversial reports, there is growing in-vitro and in-vivo evidences of anti-staphylococcal biofilm activity of macrolides that could represent a significant advance in the battle against implant-related infections. 

 
Rev Esp Quimioter 2012:25(1):10-16 [pdf]