Pretreatment of urine samples with SDS improves direct identification of urinary tract pathogens with matrix-assisted laser desorption ionization-time of flight mass spectrometry.

We pretreated with SDS 71 urine samples with bacterial counts of >10(5) CFU/ml and matrix-assisted laser desorption ionization-time of flight (MALDI-TOF) identification scores of <2, in order to minimize failure rates. Identification improved in 46.5% of samples, remained unchanged in 49.3%, and worsened in 4.2%. The improvement was more evident for Gram-negative (54.3%) than for Gram-positive (32%) bacteria.

Real-life experience of hepatitis C treatment in a Spanish prison.

OBJECTIVE: Hepatitis C virus (HCV) infection is a major public health problem that causes multiple comorbidities. People in prisons who inject intravenous drugs are at increased risk of HCV infection, and HCV infection is 15-fold more prevalent among prisoners compared with the community. The objective of this study was to analyse the clinical and epidemiological characteristics of residents of a Spanish prison with HCV infection who received antiviral treatment. METHODS: An observational, descriptive and retrospective study was performed. All patients with HCV infection diagnosed or followed up in an Infectious Diseases attached to a penitentiary were included in this study. RESULTS: Of 81 patients analysed, sixty-nine (83.1%) patients were male. The mean age was 50.1 (SD8.8) years, and 70% of the inmates had a history of injection drug use. Coinfection with HIV was detected in 30%. In up to 25% of the sample, there were data on chronic liver disease in the degree of liver cirrhosis. The diagnosis of HCV infection had been made more than 15 years earlier in 28% of those studied. Decompensations from liver disease, hepatocellular carcinoma, or hospital admissions were exceptional. Most of the inmates with HCV accepted treatment, and approximately 94% of the patients who completed treatment achieved a sustained virological response without interactions or complications of interest. CONCLUSIONS: The availability of direct-acting antivirals and their exceptional side effects constitute an opportunity to reduce the burden of HCV infection in Spain, particularly in these high-risk populations.

[Problematic bacteria]. / Bacterias problemáticas.

INTRODUCTION: Because of the special characteristics of the critical patients, infections are one of the primary complications they suffer so that multiresistant microorganisms take on a special importance in this type of patient. SOURCES: Search in Medline using the words ICU (Intensive Care Unit), multidrug resistant, critical patient. DEVELOPMENT: Glycopeptide resistant enterococci show a reduced prevalence in our setting and the VISA and hVISA are isolated sporadically. MRSA is, on the other hand, a major problem. In 2003-2005, it was already accounting for 28 %-38 % of the S. aureus isolated in the ICU, with a high percentage of fluoroquinolone (>90 %) and macrolide (>65 %) co-resistance. The extended-spectrum beta-lactamase producing enterobacteria (BLEE) also are a growing problem, worsened by their frequent co-resistance with fluoroquinolones, about 30 % according to some studies. Carbapenem resistance in A. baumannii has doubled in recent years, with values greater than 50 %, almost always associated to enzymes of the OXA group. P. aeruginosa also maintains high resistance values (25 %-30 % of resistance to imipenem, ceftazidime or ciprofloxacin), but more stable. However, high rates of multi-resistance are also observed, now about 50 % of the isolations of imipenem resistant P. aeruginosa are also to fluoroquinolones. As a whole, recent studies show that the multiresistance has multiplied in recently years by 5 in P. aeruginosa and by 7 in A. baumannii. CONCLUSIONS: Multiresistant bacteria infections are one of the greatest problems to combat in critical patients and control of their spreading and the development of active antimicrobials against them is one of the principal challenges at present.

In vitro susceptibility of community-acquired urinary tract pathogens to commonly used antimicrobial agents in Spain: a comparative multicenter study (2002-2004).

The susceptibility patterns of 2724 uropathogens isolated in 9 Spanish regions during 2002, and 3013 obtained in 2004 were determined. The antibiotics tested were fosfomycin trometamol, amoxicillin, co-amoxiclav, cefixime, cefuroxime-axetil, pipemidic, ceprofloxacin, trimethoprim plus sulphamethoxazole and nitrofurantoin. Escherichia coli was the main pathogen in both studies (73% vs. 68.3%) followed by Proteus mirabilis 7.2% vs. 6.4%) and Klebsiella pneumoniae (5.4% vs. 5.2%). Enteroccocus spp. (4.7% vs. 6.8%), Streptoccocus agalactiae (1.7% vs. 3.1%) and Staphyloccocus saprophyticus (0.7% vs. 1.3%)were the most frequent Gram-positive pathogens. 31.3% of E. coli in 2002 and 32% in 2004 were susceptible to all antibiotics tested. Around 40% of E. coli were resistant to a single agent. 21.6-24.1% were resistant to two antibiotics. 35.4% of first period isolates, and 37.6% of second period ones were resistant to two or more classes of antibiotics. Fosfomycin (2.1- 2.8%) and nitrofurantoin (3.5-5.7%) had the lowest resistance rates for E. coli. Amoxicillin (58.2-58.7%), co-trimoxazole (30.8-33.8%) and ciprofloxacin (22.6-22.7%) showed the highest resistance rates, and their suitability as empiric treatments for UTI should probably be re-evaluated.

Mechanisms of resistance to daptomycin in Staphylococcus aureus.

Daptomycin is a cyclic lipopeptide active against multidrug-resistant Gram-positives, including methicillin-resistant Staphylococcus aureus (MRSA) and S. aureus with reduced susceptibility to vancomycin. It is 4-8 fold as active as vancomycin against methicillin-susceptible S. aureus (MSSA) and MRSA, and retains most of this activity against S. aureus with reduced susceptibility to vancomycin. The mechanism of action of daptomycin is not fully understood. Daptomycin binds to the bacterial cytoplasmic membrane, leading to depolarization due to the loss of potassium ions from the cytoplasm. Daptomycin non-susceptibility is unusual in the clinical setting. Different mechanisms have been proposed to explain daptomycin-resistance, most of them associated to changes in composition, charge and fluidity of the cell wall. The mprF mutations, which lead to an increase in the lysyl-phosphatidyl glycerol production, and rpoB and rpoC mutations (rpo genes encode for bacterial RNA polymerase subunits) have been proposed as associated to daptomycin-resistance, but a number of mutations in other genes ( walK, cls, ggrA…) have been proposed.

Molecular epidemiology of drug-resistant Salmonella Typhimurium in Spain.

One hundred and forty-seven Salmonella serotype Typhimurium strains isolated in three provinces in the midwest of Spain were studied. Of these, 93.6% were drug resistant. There were two predominant resistance phenotypes: 43 isolates (29.3%) were resistant to amoxicillin, tetracyclines, chloramphenicol, streptomycin and sulphamethoxazole and 27 isolates (18.4%) to amoxicillin, amoxicillin/clavulanic acid, tetracyclines, chloramphenicol, streptomycin and sulphamethoxazole. Randomly amplified polymorphic DNA (RAPD) analysis and pulsed field gel electrophoresis (PFGE) were performed for molecular typing. Thirty-six DNA band profiles were differentiated by RAPD, and 38 by PFGE. We found a high level of clonality; 27% of strains were identical by both methods. There were additional smaller clonal lines within every area. The highest discriminatory power was obtained with PFGE, but the greatest degree of genetic diversity was observed among Salmonella Typhimurium using both RAPD and PFGE.

Full coding hepatitis E virus genotype 3 genome amplification method.

Hepatitis E virus (HEV) genotype 3 produces zoonotic infection associated with the consumption of infected animals. HEV infections can become chronic in immunocompromised (IC) patients. The viral genome has three well defined open reading frames (ORF1, ORF2 and ORF3) within which various domains and functions have been described. This paper (i) describes a new method of complete sequencing of the HEV coding region through overlapping PCR systems, (ii) establishes a consensus sequence and polymorphic positions (PP) for each domain, and (iii) analyzes the complete coding sequence of an IC patient. With regard to the consensus, a high percentage of PP was observed in protease (PP=19%) and the X domain (PP=22%) within ORF1, the N-terminal region of the S domain (PP=22%) in ORF2, and the P1 (PP=35%) and P2 (PP=25%) domains in ORF3. In contrast, the ORF1 Y, ORF2 S, ORF2 M and ORF3 D1 domains were conserved in the reference sequences (0.40, 1, 0.70 and 0% of PP, respectively). The sequence from the IC patient had more mutations in the RpRp (D1235G, Q1242R, S1454T, V1480I, I1502 V, K1511R, G1373 V, E1442D, V1693 M), the terminal ORF2 S- domain (F10L, S26T, G36S, S70P, A105 V, I113 V), the X domain (T938 M, T856 V, S898A) and the helicase (S1014N, S975T, Q1133 K).

[Prevalence of anti-Chlamydophila pneumoniae antibodies in patients with intrinsic asthma]. / Prevalencia de anticuerpos frente a Chlamydophila pneumoniae en pacientes con asma intrinseca.

Chlamydophila pneumoniae is a respiratory pathogen which has been involved in the pathogenesis of a number of chronic diseases. We studied the association between IgG antibodies against C. pneumoniae and intrinsic asthma in adults. C. pneumoniae IgG serum titers were determined by enzymatic immunoassay in 55 adult patients and 87 healthy controls. A significant association was found between anti-C. pneumoniae antibodies and intrinsic asthma, as compared to the control group (23.6% vs. 10.3%, p <0.05). C. pneumoniae may therefore be involved in the origin or in exacerbations of intrinsic asthma.

Imported transmissible diseases in minors coming to Spain from low-income areas.

We prospectively studied the prevalence of imported transmissible diseases in 373 immigrant children and adolescents coming from Sub-Saharan Africa, North Africa and Latin America to Salamanca, Spain. The most frequent transmissible diseases in this group were latent tuberculosis (12.7%), chronic hepatitis B virus infection (4.2%), hepatitis C virus infection (2.3%), syphilis (1.5%) and human T-lymphotropic virus type 1 or 2 infections (1.4%). A total of 24.2% of patients had serologic profiles suggesting past hepatitis B virus infection. Anti-human immunodeficiency virus antibodies were not detected in any subject. Largely asymptomatic immigrant children show a high prevalence of communicable diseases. Thus, infectious disease screenings are highly advisable in immigrant children coming from low-income countries.

Current status of bacterial resistance to third-generation cephalosporins.

A review of the evolution of bacterial resistance to third-generation cephalosporins is presented, focusing mainly on the prototypical member of this group-cefotaxime. Third-generation cephalosporins generally remain highly active against most Enterobacteriaceae, staphylococci, streptococci, Haemophilus, and Neisseriaceae. Only enterobacteria with a high frequency of mutant derepressed strains that hyperproduce chromosomally mediated beta-lactamase, Pseudomonas spp., and some glucose nonfermenter Gram-negative bacilli have demonstrated increased levels of resistance. The significance of derepressed strains and of the recently described extended-spectrum, plasmid-mediated beta-lactamases to the usefulness of the third-generation cephalosporins is discussed.

Review of pulmonary brucellosis: a case report on brucellar pulmonary empyema.

In certain geographic areas, among which most South European countries are included, brucellosis continues to be an important health problem. Despite the disease's continued high prevalence, the advances made in its diagnosis and treatment have contributed to the rarity of different focal locations, such as the lung. Formerly, these occurrences were much more frequent. The present work offers a review of the literature on pulmonary brucellar affection and describes a case report of brucellar pulmonary empyema with isolation of Brucella melitensis from the pleural exudate. This constitutes an exceptional circumstance even in areas considered hyperendemic, such as a large part of Spain.

Antibiotic susceptibility profile of Xanthomonas maltophilia. In vitro activity of beta-lactam/beta-lactamase inhibitor combinations.

The susceptibility of 42 strains of Xanthomonas (Pseudomonas) maltophilia to 37 antibiotics (mainly beta-lactams, aminoglycosides, and fluorinated quinolones) was tested. Xanthomonas maltophilia was resistant to most beta-lactams, with ceftazidime, moxalactam, and ICI-194008 being the most active ones. Aminoglycosides had a very modest activity, with quinolones showing only moderate activity against this species. Trimethoprim/sufamethoxazole was effective against all strains tested. We also tested the synergy of several beta-lactam/beta-lactamase inhibitors against X. maltophilia. Only aztreonam/clavulanic acid at 3:1, 1:1 and, mainly, 2:1 combinations had synergistic activity, decreasing the rate of resistance from 92.8% for aztreonam alone to 32.4% for aztreonam-clavulanic acid at 1:1 and 0% for aztreonam-clavulanic acid at 2:1.

The role of fluoroquinolones in respiratory tract infections: community acquired pneumonia.

Newer fluoroquinolones may play an important role in the management of community acquired pneumonia. They retain activity similar to older fluoroquinolones against Gram-negative bacteria and are significantly more active against Gram-positive bacteria, especially pneumococci. They are also active against bacteria causing atypical pneumonia, penicillin-sensitive and -resistant and macrolide-sensitive and -resistant pneumococci and against beta-lactamase producing and non-producing Haemophilus influenzae. They have similar or slightly lower activity than ciprofloxacin against other Gram-negative organisms. They have rapid bactericidal activity and attain good lung tissue levels. Clinical studies show results similar or better than older treatments. Their impact on ecology and resistance remains to be elucidated but data on side effects and toxicity must be carefully evaluated.

Antimicrobial activity of psychotropic drugs: selective serotonin reuptake inhibitors.

Psychotropic drugs have been shown to have antimicrobial activity against several groups of microorganisms. Some of these drugs, such as the new antidepressant agents sertraline, fluoxetine and paroxetine are known to act as efflux pump inhibitors in human cells. Their activity has been studied, alone and combined with antibiotics, against bacterial species, mainly in multiply resistant strains. These agents have surprising activity, mainly against Gram positive microorganisms. They also show synergistic activity when combined with some antibiotics against several bacteria, shown by a decrease in MICs, that converts strains previously resistant to the category of sensitive, and modify physiological aspects related with pathogenicity.

Oral cephalosporins: current perspectives.

Oral cephalosporins had been, for years, a small group of compounds belonging to the first or second-generation cephalosporins, with a limited antimicrobial spectrum. New oral first-generation cephalosporins include cefprozil and loracarbef, similar to cefadroxil and cefaclor, respectively, with activity similar to cefaclor but with pharmacokinetic improvements. Second-generation oral cephalosporins are esters of already available cephalosporins, and third-generation oral cephalosporins include a number of drugs whose activity is similar to available parenteral drugs, showing pharmacokinetic advantages and, some of them, better resistance to hydrolysis mediated by extended wide-spectrum beta-lactamases. They may be a good alternative against mild to moderate ENT infections, UTIs, STDs, lower respiratory tract and skin and soft tissue infections, mainly in the outpatient setting.

In vitro activity of newer antibiotics against Corynebacterium jeikeium, Corynebacterium amycolatum and Corynebacterium urealyticum.

The in vitro activity of ciprofloxacin, erythromycin, telithromycin, teicoplanin, linezolid and quinupristin-dalfopristin was tested against human derived pathogenic corynebacteria. The MICs of these antibiotics were measured using the agar dilution method against 31 strains of Corynebacterium jeikeium, 58 Corynebacterium amycolatum (including 33 multidrug-resistant strains) and 64 Corynebacterium urealyticum clinical strains. A high resistance rate to ciprofloxacin and erythromycin was found in the three species. Telithromycin was much more active than erythromycin (MIC(90) of erythromycin >or=128 mg/l for all three species; MIC(90) of telithromycin: 4 mg/l for C. jeikeium, 64 mg/l for C. amycolatum and 1 mg/l for C. urealyticum). There were no teicoplanin-resistant (MIC(90) 1, 0.5 and 1 mg/l, respectively) or linezolid-resistant strains (MIC(90) 1, 0.2 and 0.5 mg/l, respectively). Quinupristin-dalfopristin was active against most strains with an activity similar to linezolid, but three C. jeikeium and one C. amycolatum showed MICs >or=4 mg/l. Telithromycin showed much better activity against corynebacteria than older macrolides. Synercid and linezolid were active against most isolates tested, including multidrug resistant strains.

In vitro activity of linezolid, synercid and telithromycin against genetically defined high level fluoroquinolone-resistant methicillin-resistant Staphylococcus aureus.

The in vitro activity of levofloxacin, moxifloxacin, gatifloxacin, erythromycin, telithromycin, linezolid, synercid and vancomycin was measured against 36 genetically defined, gyrA/grlA double mutant MRSA clinical strains with an MIC to ciprofloxacin > or = 8 mg/l. The three newer fluoroquinolones tested were more active than ciprofloxacin. Resistance rates for levofloxacin and gatifloxacin were high (44.5 and 36.1%, respectively). All the strains were moxifloxacin-susceptible, though most of them had MICs close to the break point. All the strains were intermediate or resistant to erythromycin and most were also resistant to telithromycin. No strains were resistant to linezolid, synercid or vancomycin (MIC(90): 2, 1 and 2 mg/l, respectively).

Kinetics of antimicrobial activity of amoxicillin/clavulanic acid and metronidazole against beta-lactamase-producing Bacteroides fragilis group.

Bacteroides fragilis group are the most common anaerobic bacteria isolated in clinical specimens. The use of a beta-lactam with a beta-lactamase inhibitor should result in a marked increase in the group's sensitivity to the beta-lactams. Since the activity (MIC) shown by the amoxicillin + clavulanic acid combination against Bacteroides fragilis group is good, other parameters of in vitro activity have been studied. This study was also done with metronidazole. The minimum inhibitory concentration (MIC) was determined in 26 strains of Bacteroides fragilis group (14 B. fragilis; 5 B. thetaiotaomicron; 4 B. vulgatus; 3 B. distasonis). Likewise, the minimum bactericidal concentration (MBC), the killing curve, the sub-MIC and post-antibiotic effect were determined. The MIC ranged between 0.5 and 32 mg/l. The MBC was two- to four-fold the MIC for amoxicillin/clavulanic acid, and one- to two-fold the MIC for metronidazole for most strains. The killing curve showed a continuous decrease, sloping most sharply between 0-2 hours and 6-8 hours. Amoxicillin + clavulanic acid showed a post-antibiotic effect between 2 and 4 hours. The inhibitory minimum antibiotic concentration was one-half the MIC for most strains.

In-vitro activity of meropenem, a new carbapenem, against imipenem-resistant Pseudomonas aeruginosa and Xanthomonas maltophilia.

The activity of meropenem, a new carbapenem, as well as imipenem, ceftazidime, aztreonam, tobramycin, amikacin and ciprofloxacin against 18 strains of Xanthomonas maltophilia and 23 strains of Pseudomonas aeruginosa resistant to imipenem was tested. All strains of X. maltophilia were resistant to both penems. Ceftazidime, tobramycin and ciprofloxacin were the most active antimicrobial agents against this specie. 17% of imipenem-resistant strains of P. aeruginosa were sensitive to meropenem. Ciprofloxacin, amikacin and aztreonam were the most effective agents against these strains.

[In vitro activity of moxifloxacin against respiratory pathogens in Latin America]. / Actividad in vitro de moxifloxacino frente a patógenos respiratorios en Iberoamérica.

We compared the in vitro activity of moxifloxacin, levofloxacin and six other antibiotics frequently used in respiratory tract infections, against 1563 Streptococcus pneumoniae, Streptococcus pyogenes, Staphylococcus aureus, Haemophilus influenzae and Moraxella catarrhalis clinical isolates from 21 centers in 10 Latin American countries from March 2000 to April 2001. Moxifloxacin was the most active compound against all the species included. Moxifloxacin was 2- to 4-fold more active than levofloxacin against Gram-positive bacteria. This difference was much higher against levofloxacin-resistant S. pneumoniae isolates (MIC: 0.5 mg/l vs 8 mg/l). The activity of moxifloxacin against H. influenzae and M. catarrhalis was similar to levofloxacin; all the isolates were inhibited at < or = 1 mg/l concentrations of moxifloxacin and levofloxacin.