Archive for September, 2011

Are all beta-lactams similarly effective in the treatment of methicillin-sensitive Staphylococcus aureus bacteraemia?

Clinical Microbiology and Infection October 2011 V.17 N.10 P.1581-1586

M. Paul1,2, N. Zemer-Wassercug1, O. Talker1, Y. Lishtzinsky1, B. Lev3, Z. Samra2,3, L. Leibovici2,4, J. Bishara1,2

1-Unit of Infectious Diseases, Rabin Medical Center, Beilinson Hospital, Petah-Tikva, Israel

2-Sacker Faculty of Medicine, Tel-Aviv University, Ramat-Aviv, Israel

3-Microbiology Laboratory Rabin Medical Center, Beilinson Hospital, Petah-Tikva, Israel

4-Medicine E, Rabin Medical Center, Beilinson Hospital, Petah-Tikva, Israel

*Correspondence: Corresponding author: M. Paul, Infectious Diseases Unit, Rabin Medical Center, Beilinson Hospital, Sackler Faculty of Medicine, Tel Aviv University, Tel Aviv, Israel E-mail:


Methicillin-sensitive Staphylococcus aureus (MSSA) is susceptible to many beta-lactams. We compared cloxacillin and cefazolin, the first-line recommended antibiotics, and other beta-lactams in the treatment of MSSA bacteraemia. This was a retrospective cohort study. Included were adult patients with clinically-significant MSSA bacteraemia treated with a beta-lactam that was started within 48 h after blood cultures were taken. We separated between empirical treatment administered to the patient before receipt of final blood culture results and definitive treatment administered thereafter. Univariate and multivariable analyses for 30-day (empirical treatment) and 90-day (definitive treatment) mortality were conducted, including the type of beta-lactam administered to the patient. Five-hundred and forty-one patients were included for the analysis of empirical treatment and 498 patients alive at 7 days were evaluable for definitive treatment. Empirical treatment with cloxacillin or cefazolin (n = 131) was associated with lower 30-day mortality as compared with cefuroxime (n = 98, p 0.058), ceftriaxone or cefotaxime (n = 194, p 0.008) and beta-lactam-beta-lactamase combinations (n = 61, p 0.013), with adjusted odds ratios (OR) for death ranging from 1.98 to 2.68. Definitive treatment with cefazolin (n = 72) was not significantly different from cloxacillin (n = 281); adjusted OR for 90-day mortality 0.91 (95% confidence interval 0.47–1.77). Treatment with cefazolin both in the empirical and definitive periods was not significantly different from cloxacillin; adjusted OR 0.81 (95% confidence interval 0.18–3.62). Treatment of MSSA bacteraemia with cefazolin is not significantly different from treatment with cloxacillin, while treatment with other beta-lactams, including second and third generation cephalosporins, might be associated with higher mortality.


September 26, 2011 at 3:46 pm Leave a comment

Clonal dissemination of Klebsiella pneumoniae ST258 harbouring KPC-2 in Argentina

Clinical Microbiology and Infection October 2011 V.17 N.10 P.1520-1524


S. A. Gomez1,†, F. G. Pasteran1,‡, D. Faccone1, N. Tijet2, M. Rapoport1, C. Lucero1, O. Lastovetska2,3,4, E. Albornoz1, M. Galas1, KPC Group

1-Servicio Antimicrobianos, Instituto Nacional de Enfermedades Infecciosas (INEI)-ANLIS ‘Dr Carlos G. Malbrán;, Ciudad Autónoma de Buenos Aires, Argentina

2-Ontario Agency for Health Protection and Promotion, Public Health Laboratories

3-Department of Laboratory Medicine & Pathobiology, University of Toronto

4-Department of Microbiology, Mount Sinai Hospital, Toronto, ON, Canada

*Correspondence: Corresponding author: S. A. Gomez, Servicio Antimicrobianos, Instituto Nacional de Enfermedades Infecciosas (INEI)-ANLIS ‘Dr Carlos G. Malbrán’, Av. Velez Sarsfield 563, 1282AFF, Ciudad Autónoma de Buenos Aires, Argentina E-mail:


The present work describes the abrupt emergence of Klebsiella pneumoniae carbapenemase (KPC) and characterizes the first 79 KPC-producing enterobacteria fromArgentina(isolated from 2006 to 2010). The emergence of blaKPC-2 was characterized by two patterns of dispersion: the first was the sporadic occurrence in diverse enterobacteria from distant geographical regions, harbouring plasmids of different incompatibility groups and blaKPC-2 inan unusual genetic environment flanked by ISKpn8-ΔblaTEM-1 and ISKpn6-like. blaKPC-2 was associated with IncL/M transferable plasmids; the second was the abrupt clonal spread of K. pneumoniae ST258 harbouring blaKPC-2 inTn4401a.


September 26, 2011 at 3:44 pm Leave a comment

Fever in a returned traveler.

Cleve Clin J Med. 2005 Oct;72(10):921-7.

Lesho EP, George S, Wortmann G.

Walter Reed Army  Medical Center, Washington, DC, USA.


September 26, 2011 at 1:00 am Leave a comment

Fever in returned travelers: results from the GeoSentinel Surveillance Network.

Clin Infect Dis. 2007 Jun 15;44(12):1560-8.

Wilson ME, Weld LH, Boggild A, Keystone JS, Kain KC, von Sonnenburg F, Schwartz E; GeoSentinel Surveillance Network.

Mount Auburn Hospital, Cambridge, MA, USA.



Fever is a marker of potentially serious illness in returned travelers. Information about causes of fever, organized by geographic area and traveler characteristics, can facilitate timely, appropriate treatment and preventive measures.


Using a large, multicenter database, we assessed how frequently fever is cited as a chief reason for seeking medical care among ill returned travelers. We defined the causes of fever by place of exposure and traveler characteristics.


Of 24,920 returned travelers seen at a GeoSentinel clinic from March 1997 through March 2006, 6957 (28%) cited fever as a chief reason for seeking care. Of patients with fever, 26% were hospitalized (compared with 3% who did not have fever); 35% had a febrile systemic illness, 15% had a febrile diarrheal disease, and 14% had fever and a respiratory illness. Malaria was the most common specific etiologic diagnosis, found in 21% of ill returned travelers with fever. Causes of fever varied by region visited and by time of presentation after travel. Ill travelers who returned from sub-Saharan Africa, south-central Asia, and Latin  America whose reason for travel was visiting friends and relatives were more likely to experience fever than any other group. More than 17% of travelers with fever had a vaccine-preventable infection or falciparum malaria, which is preventable with chemoprophylaxis. Malaria accounted for 33% of the 12 deaths among febrile travelers.


Fever is common in ill returned travelers and often results in hospitalization. The time of presentation after travel provides important clues toward establishing a diagnosis. Preventing and promptly treating malaria, providing appropriate vaccines, and identifying ways to reach travelers whose purpose for travel is visiting friends and relatives in advance of travel can reduce the burden of travel-related illness.



September 26, 2011 at 12:56 am Leave a comment

Evaluating a sick child after travel to developing countries.

J Am Board Fam Med. 2010 Nov-Dec;23(6):704-13.

Tolle MA.

Department of Pediatrics, Baylor College of Medicine, Houston, TX 77030,


Every year, millions of children travel internationally with their families, many to developing countries. Although the vast majority experience uneventful travel and return home well, it is not uncommon for children to present as ill during or after travel. Although the majority of travel-associated illness is mild and self-limited, serious conditions regularly occur. Almost all life-threatening conditions after travel present with fever, and malaria is the most important of these to rapidly exclude. Gastrointestinal symptoms are common after travel in the developing world, and most diarrhea in child travelers has a bacterial
source. Children who have a rash in association with fever or who appear ill should receive a priority work-up focused on ruling out serious conditions. Many children traveling internationally experience respiratory illness during or shortly after travel, mainly common upper respiratory infections, yet serious conditions, such as tuberculosis, may occur. Eosinophilia is common in the returned pediatric traveler, particularly those with prolonged stays in the tropics. Not all eosinophilia is caused by parasitic infection; drug reactions, asthma, and other allergic conditions are also common causes. With a focus first on ruling out life-threatening disease and subsequently on an informed and efficient path to diagnosis and treatment, clinicians may confidently
provide care for this challenging group of patients.



September 26, 2011 at 12:52 am Leave a comment

Rickettsia typhi infection with interstitial pneumonia in a traveler treated with moxifloxacin.

J Clin Microbiol. 2011 Feb;49(2):741-3.

Schulze MH, Keller C, Müller A, Ziegler U, Langen HJ, Hegasy G, Stich A.

Medical Mission Hospital, Department of Tropical Medicine, Salvatorstrasse 7, 97067 Würzburg, Germany.


Rickettsial diseases may play an important part in the differential diagnosis of fever in returned travelers. The initial empirical treatment needs to take Rickettsia species into consideration to avoid the development of life-threatening courses. Here, we
present a case of interstitial pneumonia associated with Rickettsia typhi infection treated with moxifloxacin.



September 26, 2011 at 12:47 am Leave a comment

Endobronchial tuberculosis: an overview

European J of Clin Microbiol & Infect Dis. Aug 2011 V.30 N.9 P.1039-1044


Q. Xue, N. Wang, X. Xue and J. Wang


Endobronchial tuberculosis (EBTB), of which the incidence has been increasing in recent years, is a special type of pulmonary tuberculosis. The endobronchial tuberculose focuses often injure the tracheobronchial wall and lead to tracheobronchial stenosis. The tracheobronchial stenosis may cause intractable tuberculosis and make patients become chronic infection sources of tuberculosis, or may even cause pulmonary complications and result in death. The etiological confirmation of Mycobacterium tuberculosis is most substantial for diagnosis. However, because the positive rate of acid-fast bacillus staining for sputum smears is low and the clinical and radiological findings are usually nondistinctive, the diagnosis of EBTB is often mistaken and delayed. For early diagnosis, a high index of awareness of this disease is required and the bronchoscopy should be performed as soon as possible in suspected patients. The eradication of Mycobacterium tuberculosis and the prevention of tracheobronchial stenosis are two most substantial treatment goals. To get treatment goals, the diagnosis must be established early and aggressive treatments must be performed before the disease progresses too far.


September 23, 2011 at 5:58 pm Leave a comment

The rate of accumulation of nonnucleoside reverse transcriptase inhibitor (NNRTI) resistance in patients kept on a virologically failing regimen containing an NNRTI†

HIV Medicine Aug 2011

A Cozzi-Lepri1,2, R Paredes3, AN Phillips1, B Clotet3, J Kjær4, V Von Wyl5, G Kronborg6, A Castagna7, JR Bogner8, JD Lundgren4,9, for EuroSIDA in EuroCoord

1Department of Infection & Population Health, Division of Population Health, University College London, London, UK

2Division of Biostatistics, University of Minnesota, Minneapolis, MN, USA

3HIV Unit and irsiCaixa Retrovirology Lab, Hospital Universitari Germans Trias i Pujol, Barcelona, Spain

4Copenhagen HIV Programme, University of Copenhagen, Panum Institute, Copenhagen, Denmark

5Division of Infectious Diseases and Hospital Epidemiology, University Hospital Zurich, ETH Zurich, Zurich, Switzerland

6Department of Infectious Diseases and Clinical Research Centre, Hvidovre 6 University Hospital, Hvidovre, Denmark

7Istituto di Ricovero e Cura a Carattere Scientifico, San Raffaele Vita-Salute University, Milan, Italy

8Medizinische Poliklinik, Department of Infectious Diseases, University of Munich Medical School, Munich, Germany

9Centre for Viral Diseases, Department of Infectious Diseases, Rigshospitalet, Copenhagen, Denmark

*Correspondence: Dr Alessandro Cozzi-Lepri, Research Department of Infection and Population Health, Division of Population Health, Royal Free & University College Medical School, Royal Free Campus, Rowland Hill Street, London NW3 2PF, UK. Tel: +1 612 626 8615; fax: +1 612 624 2819; e-mail:


Virological failure of first-generation nonnucleoside reverse transcriptase inhibitors (NNRTIs) can compromise the efficacy of etravirine as a result of the accumulation of NNRTI resistance mutations. How quickly NNRTI resistance accumulates in patients with a delayed switch from nevirapine or efavirenz despite virological failure, when these drugs are used as a component of combination antiretroviral therapy (cART), remains unclear.


The rate of NNRTI resistance accumulation was estimated in patients in EuroSIDA with at least two available genotypic resistance tests (GRTs), provided that (1) the date of the first GRT (t0) was after the date of the first virological failure (VF) of an NNRTI, and (2) patients were receiving an NNRTI and HIV RNA was >500 HIV-1 RNA copies/mL in all measurements between GRTs.


A total of 227 patients were included in the study, contributing 467 GRT pairs. At baseline-t0, a median of 3 months after VF, 66% of patients had at least one NNRTI mutation: 103N (34%),181C(22%) and 190A (20%) were the most common mutations. Overall, 180 additional NNRTI mutations were found to have accumulated over 295 years [1 new/1.6 years; 95% confidence interval (CI) 1.5–1.8]. The rate of accumulation was faster in the first 6 months from VF (1 new/1.1 years), and slower in patients exposed to nevirapine vs. those receiving efavirenz [relative risk (RR) 0.66; 95% CI 0.46–0.95; P=0.03].


There is an initial phase of rapid accumulation of NNRTI mutations close to the time of VF followed by a phase of slower accumulation. We predict that it should take approximately one year of exposure to a virologically failing first-generation NNRTI-based cART regimen to reduce etravirine activity from fully susceptible to intermediate resistant, and possibly longer in patients kept on a failing nevirapine-containing regimen.


September 23, 2011 at 5:56 pm Leave a comment

Colonization and Infection by Colistin Resistant Gram Negative Bacteria in a Cohort of Critically Ill Patients

Clinical Microbiology and Infection Aug 2011

Flora Kontopidou1, Diamantis Plachouras1, Evangelos Papadomichelakis2, Georgios Koukos1, Irene Galani1, Garyfallia Poulakou1, Georgios Dimopoulos2, Anastasia Antoniadou1, Apostolos

14th Dept. of Internal Medicine

22nd Critical Care Dept., University of Athens, Medical School, Athens, Greece

*Correspondence: Corresponding author: Diamantis Plachouras Lecturer in Internal Medicine – Infectious Diseases 4th Department of Internal Medicine Medical School, University of Athens University Hospital “Attikon” Rimini 1 12462 Athens, Greece Tel: +30 2105831664 Fax: +30 2105326446 e-mail:


In recent years there has been renewed interest in colistin for the treatment of infections by multi-drug resistant Gram-negative bacteria, causing concern that, increasing use may be accompanied by the emergence of resistance.

This is a retrospective cohort study of colonization and infection by colistin resistant (CR) gram negative bacteria in critically ill patients. Colonization data were based on surveillance culture results. Among 150 patients, seventy-eight (52%) were colonized by CR Gram-negative bacteria. Among them thirty (20%) were colonized by Klebsiella pneumoniae isolates and 51 (34%) were colonized by intrinsically resistant to colistin (CIR) enterobacteriaceae. Seven cases of infection were caused by CR K. pneumoniae and 12 cases by CIR strains. The main risk factor for colonization by CR pathogens was colistin treatment.


September 23, 2011 at 5:54 pm Leave a comment

Microbial Genomics and Infectious Diseases

N Engl J Med  2011 V.365 P.347-357


David A. Relman, M.D.

The pace of technical advancement in microbial genomics has been breathtaking. Since 1995, when the first complete genome sequence of a free-living organism, Haemophilus influenzae, was published,1 1554 complete bacterial genome sequences (the majority of which are from pathogens) and 112 complete archaeal genome sequences have been determined, and more than 4800 and 90, respectively, are in progress.2 A total of 41 complete eukaryotic genome sequences have been determined (19 from fungi), and more than 1100 are in progress. Complete reference genome sequences are available for 2675 viral species, and for some of these species, a large number of strains have been completely sequenced…..



September 21, 2011 at 3:09 pm Leave a comment

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