Rev Esp Quimioter 2010:23(2):53-62

The microbiologist and the catheter related infection

J. GARCÍA-RODRÍGUEZ, M. DE PABLOS, A. GUTIÉRREZ

 

Different multicentre epidemiological studies such as ENVIN-HELICS or EPINE, have remarked that catheter related bloodstream infection (CRBI) is an increasingly condition in hospital environment. The microbiologist plays a major role in the diagnosis, either by recommending what type of catheter must be considered for confirmatory diagnosis, when these samples must be sent for culture, when is indicated to perform surveillance studies of the catheter and what results are clinically significant to be informed. In this paper, differentaspects of the CRBI, such as the pathogenesis, etiology, epidemiology and diagnosis are reviewed. The different microbiological diagnostic methods, both conservatives and those involving the removal of the catheter are up-to-dated.

 
Rev Esp Quimioter 2010:23(2):53-62 [pdf]

Rev Esp Quimioter 2010:23(4):184-189

Experience of micafungin in patients requiring extrarenal depuration 

F. ALVAREZ-LERMA, S. GRAU, Y. DÍAZ, J. FERNÁNDEZ   

 

Introduction. The use of extrarenal depuration techniques is increasingly frequent in patients admitted to the ICU. The use of these procedures has been related to a decrease in plasma concentrations of several antimicrobials, among which fluconazole. The activity of antifungal agents depends on achievement on adequate concentrations in plasma and at the site of infection. Micafungin is a new antifungal drug recently introduced in our country.
Objective. To review the published experience of pharmacokinetic (PK) parameters of micafungin in patients requiring some type of extrarenal depuration procedures during their stay in the ICU.
Results. Three studies with data on PK parameters of micafungin during the use of this drug in continuous venovenous hemodialysis (2 publications) and continuous hemodiafiltration (1 publication) were retrieved. In all of them, minimal variations in the plasma concentration of micafungin at the entry and exit sites of the hemofilter and a negligible or minimal presence of micafungin in the ultrafiltration fluid were demonstrated.
Conclusions. Adjustment of the doses or the interval between doses of micafungin during the use of extrarenal depuration techniques in critically ill patients admitted to the ICU is not necessary.   

 
Rev Esp Quimioter 2010:23(4):184-189 [pdf]

Rev Esp Quimioter 2011:24(2):91-95

Antimicrobial susceptibility of methicillin-resistant Staphylococcus aureus strains from outpatient individuals    

L. GARCÍA-AGUDO, M. HUERTAS, M. A. ASENCIO EGEA, R. CARRANZA, P. GARCÍA-MARTOS         

 

Background: Community-associated methicillin-resistant Staphylococcus aureus (CA-MRSA) has emerged worldwide as a cause of infections among patients without risk factors. This CA-MRSA is different from nosocomial strains in terms of epidemiology, microbiology and clinical manifestations. We report the epidemiologic characteristics and resistance to antimicrobial agents of CA-MRSA strains isolated in the last three years in the Microbiology Lab of Hospital General La Mancha-Centro (Alcázar de San Juan, Ciudad Real).
Methods: We performed a retrospective analysis of microbiological cultures in patients with S. aureus diagnosed from 2007 to 2009 in La Mancha-Centro Health-Care Area, within Castilla-La Mancha Community.
Results: The distribution of CA-MRSA in the studied period was 26 out of a total of 97 S. aureus isolates in 2007 (26.8%), 40/113 in 2008 (35.4%) and 57/157 in 2009 (36.3%). The percentage from purulent skin and soft tissue infections was 63.4%. All strains were susceptible to linezolid, quinupristin/dalfopristin, and glycopeptides. The resistance was high to fluoroquinolones (94.3%), erythromycin (87.0%), tobramycin (82.9%), and clindamycin (65.3%).
Conclusions: CA-MRSA isolates percentage increased along the period of the study. The majority were obtained from skin and soft tissue specimens. The most commonly associated antimicrobial resistance was to fluoroquinolones, erythromycin, tobramycin and clindamycin. An understanding of the CAMRSA epidemiology is important to prevent these organisms from becoming endemic in the world. 

 
Rev Esp Quimioter 2011:24(2):91-95 [pdf]

Rev Esp Quimioter 2011:24(4):204-208

Predictive factors for pneumonia in adults infected with the new pandemic A (H1H1) influenza virus          


E. LERMA, L. SORLÍ, M. MONTERO, V. MAS, E. LÓPEZ, C. VILAPLANA, F. ÁLAVAREZ-LERMA, H. KNOBEL, J. P. HORCAJADA             
 

Background: On April 2009 a new A (H1N1) influenza virus was identified with a higher incidence of severe outcome in younger people, most of them with pneumonia.The objective of our study was to identify the predictive risk factors of pneumonia in patients with the new A (H1N1) influenza virus infection.
Methods: Prospective cohort study of adults infected with the new A (H1N1) influenza virus, admitted in a universitary hospital, from june 2009 to January 2010. Pneumonia was defined as the presence of any pulmonary infiltrate of any distribution with no other evident cause, in the chest radiography. A comparative analysis was made with patients with A (H1N1) influenza without pneumonia.
Results: 281 patients with influenza A (H1N1) were treated. Thirty of them (10.6%) had pneumonia and 11 (3.9%) required intensive care. The global mortality was 0.7%. For the comparative analysis, 42 patients with influenza A (H1N1) without pneumonia were analysed (20 hospitalized and 22 nonhospitalised).
In the multivariate analysis, obesity (BMI>30), (OR: 3.8; IC 95%: 0.99-15.0), time since symptom onset until hospital admission (OR 1.34; IC 95% 1.04-1.72), serum C reactive protein levels (OR:1.10; IC 95%: 0.98-1.24) and serum IgG2 levels (OR:1.08; IC 95%: 1.0- 1.01), were identified as independent risk factors for pneumonia.
Conclusion: Obesity, delay in medical care and higher levels of C reactive protein and IgG2 were predictive factors for pneumonia in adult patients with A (H1N1) influenza infection. 

 
Rev Esp Quimioter 2011:24(4):204-208 [pdf]

Rev Esp Quimioter 2012:25(1):65-73


Analysis of treatments used in infections caused by Gram-positive multiresistant cocci in critically ill patients admitted to the ICU 
              
  

F. ÁLVAREZ-LERMA, M. PALOMAR, P. OLAECHEA, J. INSAUSTI, M. J. LÓPEZ, M. P. GRACIA, R. GIMENO, I. SEIJAS                                                          

The appearance of new antimicrobials with activity against Gram-positive multiresistant cocci and knowledge of the limitations of glycopeptides has represented an important change in the use of these antibiotics.
Objetive. To analyze at the national level changes in the use of antibiotics with specific activity against Gram-positive multiresistant cocci in critically ill patients admitted to the ICU as well as the characteristics of patients treated with these agents and the forms of administration.
Material and methods. Retrospective cohort study of patients admitted to the ICU for more than 24 hours between 2008 and 2010 in the ENVIN-HELICS national registry. Cases were defined as patients who had received one or more of the following antibiotics: vancomycin, teicoplanin, linezolid or daptomycin. The characteristics of patients who used one or more of these agents were compared with those treated with other antibiotics. Indications and forms of use of each antibiotic were assessed. Descriptive results are presented.
Results. A total of 45,757 patients, 27,982 (61.2%) of whom received 63,823 antimicrobials were included in the study. In 6,368 (13.9%) patients, one or more antibiotics specifically active against Gram-positive multiresistant cocci were given. There was a predominance of the use of vancomycin and linezolid and an important increase in the prescription of daptomycin (+320%) and linezolid (+22.4%). In more than 95% of cases, linezolid and daptomycin were prescribed for the treatment of infections, whereas vancomycin and teicoplanin were used for prophylaxis in 20-25% of cases. Between 75% and 80% of indications for treating infections, antibiotics were used empirically except for daptomycin which was used as a directed treatment in 43% of the cases. Only in one third of the indications for empirical treatment, susceptible microorganisms were identified (appropriate treatment).
Conclusions. The use of antibiotics with activity against Gram-positive multiresistant cocci remained stable around 14% of all indications. The use of vancomycin and linezolid predominated and there was a clear trend towards an increase in the use of daptomycin and linezolid and a decrease in the use of glycopeptides. Empirical treatments were considered appropriate in only one third of cases.
  

 
Rev Esp Quimioter 2012:25(1):65-73 [pdf]

Rev Esp Quimioter 2012:25(3):206-215


Impact of liposomal amphotericin B on renal function in critically ill patients with renal function impairment                 
  

F. ÁLVAREZ-LERMA, M. C. SORIANO, M. RODRÍGUEZ, M. CATALÁN, A. M. LLORENTE, N. VIDART, M. GARITACELAYA, E. MARAVÍ, E. FERNÁNDEZ, F. ALVARADO, M. LÓPEZ, B. ÁLVAREZ-SÁNCHEZ, J. ESPINOSA, E. QUINTANA AND THE STUDY GROUP OF LIPOSOMAL AMPHOTERICIN B IN THE ICU                                                                          

 
Objetive: To assess the tolerability of liposomal amphotericin B (L-AmB) in critically ill patients with elevated serum creatinine concentrations (Cr) (> 1.5 mg/dL) at starting L-AmB therapy.
Methods: Retrospective, multicenter, comparative study of two cohorts of critically ill patients treated with L-AmB during 3 or more days, the difference between them was the level of Cr at the beginning of treatment. A cutoff value of Cr of 1.5 mg/dL was established. Patients undergoing extrarenal depuration procedures before or 48 hours after starting L-AmB were excluded. The primary endpoint was the difference between Cr values at the end of treatment as compared with Cr at starting L-AmB. Secondary endpoints were treatment-related withdrawals, need of extrarenal depuration techniques, and treatment-related severe adverse events. Demographic data, underlying illness, indication of L-AmB therapy, concomitant risk factors of nephrotoxicity, and vital status at ICU and hospital discharge were recorded.
Results: A total of 122 patients admitted to 26 ICUs (16 with Cr > 1.5 g/dL; 106 with normal Cr levels) were recruited. Main reasons for the use of L-AmB in both groups were the broad spectrum of the drug and the presence of hemodynamic instability. L-AmB was administered as first-line treatment in 68.8% of patients with elevated Cr and in 52.8% with normal Cr. The APACHE II score on ICU admission was 25 in patients with elevated Cr and 17 in those with normal Cr values (p < 0.001). Duration of treatment with L-AmB was 16 and 12 days in patients with elevate and normal Cr values, respectively, with a mean dose of 3.5 vs 3.9 mg/kg/day. The use of concomiImpact tant nephrotoxic drugs, mortality rate, and ICU and hospital length of stay were similar in both cohorts. In patients with renal function impairment at the initiation of L-AmB treatment, an absolute decrease of Cf-Ci of 1.08 mg/dL was observed (P < 0.001). A decrease of Cr levels to normal limits was observed in 50% of the patients; in 37.5% of patients there was a decrease but normal levels were not achieved, whereas a Cr increased occurred in only one (6.25%) patient. None of the patients required withdrawal of L-AmB or use of extrarenal depuration procedures. Treatment-related severe adverse events were not reported.
Conclusions: In critically ill patients with impaired renal function, the impact of L-AmB on renal function was minimal. L-AmB can be used for the treatment of fungal infections in critically ill patients independently of renal function at the initiation of treatment.

 

Rev Esp Quimioter 2012:25(3):206-215 [pdf]

Rev Esp Quimioter 2010:23(2):72-75

Cefditoren versus ceftazidime in inducer-substrate combinations for the evaluation of AmpC production in a disc approximation test

F. CAFINI, L. AGUILAR, L. ALOU, M. J. GIMÉNEZ, D. SEVILLANO, M. TORRICO, N. GONZÁLEZ, P. CORONEL, J. PRIETO 

 

Objective: To evaluate cefditoren in inducer-substrate combinations to screen for AmpC induction.
Methods: 100 clinical isolates (25 P. aeruginosa, 25 E. cloacae, 14 M. morganii, 13 S. marcescens, 12 C. freundii, 7 P. rettgeri, and 4 E. aerogenes) were tested by the Kirby-Bauer disc approximation method using cefditoren and ceftazidime discs as substrates, and cefditoren and imipenem discs as inducers.
Results: None of the strains showed induction of AmpC with cefditoren-ceftazidime as inducer-substrate combination. Imipenem-cefditoren as inducer-substrate combination was not useful for evaluating strains of P. aeruginosa since no inhibition zones surrounding the cefditoren disc were found. Among evaluable enterobacteria (those showing substrate inhibition zone), inducible Amp C was detected in 48 out of 63 (76.2%) with cefditoren, and in 33 out of 68 (48.5%) isolates with ceftazidime as substrate. Significantly (p= 0.013) higher number of AmpC producers were detected with cefditoren versus ceftazidime (76.2% vs. 48.5%), due to the differences found for E. cloacae (72.8% vs. 21.7%; p= 0.0009) and S. marcescens (100% vs. 54.5%; p= 0.03). Higher mean reductions of diameters around substrate discs were found for cefditoren (4.17 mm) vs. ceftazidime (3.79 mm), reaching statistical significance (p<0.05) for indol-positive proteae: M. morganii (5.32 mm vs. 3.92 mm) and P. rettgeri (3.47 mm vs. 2.64 mm).
Conclusion: Cefditoren showed no induction capability, and when used as substrate (with imipenem as inducer) it offered detection rates of AmpC inducible enterobacteria higher than the imipenem-ceftazidime combination, mainly for Enterobacter spp. and Serratia spp., with higher diameter reductions for indol-positive proteae.

 
Rev Esp Quimioter 2010:23(2):72-75 [pdf]

Rev Esp Quimioter 2010:23(4):190-195

Significance of lower respiratory tract cultures yielding  Aspergillus spp. growth in a hospital without  transplant patients   

P. LUCENA, J. BARBERÁN, G. EROLES, J. J. GRANIZO, M. J. GIMÉNEZ, N. MIR, L. AGUILAR, J. PRIETO   

 

Introduction: Isolation of Aspergillus spp. in non-neutropenic, non-transplant patients with chronic obstructive pulmonary disease (COPD) usually treated with corticosteroids is not easily interpretable. A retrospective review of clinical records corresponding to cultures (respiratory samples) yielding Aspergillusspp. in non- transplant patients was carried out.

Methods: Patients were assigned to four categories: colonization, possible, probable or definitive aspergillosis. A logistic regression model (step–wise procedure) was performed using as dependent variable mortality, and as independent variables those showing differences (p≤0.1) in the bivariant analysis.

Results:Sixty-nine patients were identified. Most were elderly (68.1% ≥65 years), male (73.9%), presented comorbidities(84.1% Charlson index ≥3), COPD (76.8%), were receiving high corticosteroid doses (66.7%), and had previously received antibiotics (94.2%). Forty-five cases were colonizations, 4 possible, 15 probable and 5 definitive aspergillosis. A. fumigatus was isolated in 75.4% patients:  66.7% colonized, 75% possible,93.3% probable and 100% definitive aspergillosis. Colonized patients were older (71.9 ± 11.9 vs. 65.1 ± 9.2 years; p= 0.018) and presented higher (p=0.034) comorbidity index than patients with aspergillosis. Mortality was 31.1% in colonized vs. 62.5% in aspergillosis (p=0.012).

Conclusion: The isolation of A. fumigatus was associated with an increased probability of aspergillosis, with statistical association in the multivariate analysis between mortality and variables related to chemotherapy (no antifungal treatment), disease (diagnostic category) and immunity (leukocytosis).    

 
Rev Esp Quimioter 2010:23(4):190-195 [pdf]

Rev Esp Quimioter 2011:24(2):96-98

Results of a counselling programme in antibiotic treatment in a secundary hospital    

A. DEL ARCO, B. TORTAJADA, J. DE LA TORRE, J. OLALLA, J. L. PRADA, N. MONTIEL, J. GARCÍA-ALEGRÍA          

 

Background: The inappropriate use of antimicrobial agents may contribute to the development of bacterial resistance to the principal antimicrobial drugs. There is no provision in the immediate future of marketing of new broad-spectrum antibiotics, especially with activity against Enterobacteriaceae, so programs should be implemented to optimize antimicrobial therapy. We describe the results of a year of a counselling program in antibiotic treatment in a secondary Andalusian hospital.
Methods: We describe 276 interventions of a multidisciplinary non-compulsory counselling program of antimicrobial management on the Costa del Sol Hospital in Marbella. We evaluated the adequacy of empirical treatment, possibility of antibiotic de-escalation, duration and dose used. We analyzed the evolution of the sensitivity profile of the main microorganisms as well as a cost-effective analysis.
Results: 90% of the recommendations were accepted. The main actions were assessment of empirical therapy and deescalation in relation with the result of cultures. The main drugs tested were imipenem, meropenem, cefepime, and linezolid. The sensitivity profile of imipenem and meropenem improved slightly over previous years. It was found a considerable savings in annual drug spending.
Conclusions: The non-compulsory counselling programs are useful tools for optimization of antimicrobial therapy, can prevent an increase of antimicrobial resistance and reduce the cost of antibiotic treatment. 

 
Rev Esp Quimioter 2011:24(2):96-98 [pdf]

Rev Esp Quimioter 2011:24(4):209-211

Burkholderia cepacia bacteremia: a prospective analysis of 33 episodes          


M. IBARGUREN, N. COBOS-TRIGUEROS, Á. SORIANO, J. A. MARTÍNEZ, Y. ZBOROMYRSKA, M. ALMELA, J. MENSA             
 

Introduction: The aim of this study is to describe clinical characteristics and outcome of Burkholderia cepacia bacteraemia, susceptibility of the isolates and differences between cases from epidemic outbreaks and sporadic cases.
Material and methods: From 1993 to 2009, episodes of B. cepacia bacteraemia were prospectively collected in a university hospital.
Results: A total of 33 episodes were included, of which 21 were part of two outbreaks (9 in 1994 and 12 in 2006). Outbreak cases had a median age of 58 years, 45% had neoplasia, median length of stay until bacteraemia was 15 d (range 0-120) and 82% had received an antibiotic. The most prevalent sources of bacteraemia were catheter (48%) and unknown (33%). On the other hand, sporadic cases stayed longer until diagnosis (median 25 days versus 11, p=0.041) and showed a trend to have neoplasia more frequently (83% versus 33%, p=0.083). Susceptibility to antibiotics was varied and co-trimoxazole was the only active agent against all strains.
Conclusions: B. cepacia is an uncommon pathogen, which affects patients with prolonged hospitalization and severe comorbidities. The identification of more than one case in a short term of time should raise the suspicion of an outbreak. 

 
Rev Esp Quimioter 2011:24(4):209-211 [pdf]