Posts filed under ‘FIEBRE en el POSTOPERATORIO’

Molecular Diagnosis of Orthopedic-Device-Related Infection Directly from Sonication Fluid by Metagenomic Sequencing

Journal of Clinical Microbiology August 2017 V.55 N.8 P.2334-2347

Teresa L. Street, Nicholas D. Sanderson, Bridget L. Atkins, Andrew J. Brent, Kevin Cole, Dona Foster, Martin A. McNally, Sarah Oakley, Leon Peto, Adrian Taylor, Tim E. A. Peto, Derrick W. Crook, and David W. Eyre

aNuffield Department of Clinical Medicine, University of Oxford, John Radcliffe Hospital, Oxford, United Kingdom

bBone Infection Unit, Nuffield Orthopaedic Centre, Oxford University Hospitals NHS Foundation Trust, Oxford, United Kingdom

cMicrobiology Laboratory, John Radcliffe Hospital, Oxford University Hospitals NHS Foundation Trust, Oxford, United Kingdom

dDepartment of Infectious Diseases and Microbiology, Royal Sussex County Hospital, Brighton, United Kingdom

ePublic Health England, Microbiology, Royal Sussex County Hospital, Brighton, United Kingdom

fNational Institute for Health Research Oxford Biomedical Research Centre, John Radcliffe Hospital, Oxford, United Kingdom

Culture of multiple periprosthetic tissue samples is the current gold standard for microbiological diagnosis of prosthetic joint infections (PJI). Additional diagnostic information may be obtained through culture of sonication fluid from explants. However, current techniques can have relatively low sensitivity, with prior antimicrobial therapy and infection by fastidious organisms influencing results. We assessed if metagenomic sequencing of total DNA extracts obtained direct from sonication fluid can provide an alternative rapid and sensitive tool for diagnosis of PJI. We compared metagenomic sequencing with standard aerobic and anaerobic culture in 97 sonication fluid samples from prosthetic joint and other orthopedic device infections. Reads from Illumina MiSeq sequencing were taxonomically classified using Kraken. Using 50 derivation samples, we determined optimal thresholds for the number and proportion of bacterial reads required to identify an infection and confirmed our findings in 47 independent validation samples. Compared to results from sonication fluid culture, the species-level sensitivity of metagenomic sequencing was 61/69 (88%; 95% confidence interval [CI], 77 to 94%; for derivation samples 35/38 [92%; 95% CI, 79 to 98%]; for validation samples, 26/31 [84%; 95% CI, 66 to 95%]), and genus-level sensitivity was 64/69 (93%; 95% CI, 84 to 98%). Species-level specificity, adjusting for plausible fastidious causes of infection, species found in concurrently obtained tissue samples, and prior antibiotics, was 85/97 (88%; 95% CI, 79 to 93%; for derivation samples, 43/50 [86%; 95% CI, 73 to 94%]; for validation samples, 42/47 [89%; 95% CI, 77 to 96%]). High levels of human DNA contamination were seen despite the use of laboratory methods to remove it. Rigorous laboratory good practice was required to minimize bacterial DNA contamination. We demonstrate that metagenomic sequencing can provide accurate diagnostic information in PJI. Our findings, combined with the increasing availability of portable, random-access sequencing technology, offer the potential to translate metagenomic sequencing into a rapid diagnostic tool in PJI.


July 26, 2017 at 9:27 am

Recomendaciones para la prevención de infecciones asociadas a artoplastia electiva en adultos

Medicina (B. Aires) Abril 2017 V.77 N.2

Juan Carlos Chuluyán1*, Andrea Vila2*, Ana Laura Chattás3*, Marcelo Montero3*, Claudia Pensotti4*+, Claudia Tosello5*, Marisa Sánchez6*, Cecilia Vera Ocampo7*, Guillermina Kremer8*, Rodolfo Quirós8*, Guillermo A. Benchetrit9*, Carolina Fernanda Pérez10*, Ana Laura Terusi11*, Francisco Nacinovich12*

1Grupo de Trabajo Infectología, Hospital General de Agudos Dr. T. Álvarez,

2Servicio de Infectología, Hospital Italiano de Mendoza,

3Hospital General de Agudos Dr. Pirovano,

4Clínica Monte Grande,

5Hospital de Clínicas José de San Martín, UBA,

6Hospital Italiano de Buenos Aires,

7Sanatorio Dupuytren,

8Hospital Universitario Austral,

9Instituto de Investigaciones Médicas A. Lanari, UBA,

10Policlínico del Docente-Centro Médico Huésped,

11Instituto César Milstein,

12Instituto Cardiovascular de Buenos Aires, Centros Médicos Dr. Stamboulian, Argentina

*En representación del grupo de trabajo en infecciones osteoarticulares de la Sociedad Argentina de Infectología

+In memoriam

Dirección postal: Juan Carlos Chuluyan, Grupo de Trabajo Infectología, Hospital General de Agudos Dr. T. Álvarez, J. F. Aranguren 2701, 1406 Buenos Aires, Argentina



Las infecciones del sitio quirúrgico que complican las cirugías ortopédicas con implante prolongan la estadía hospitalaria y aumentan tanto el riesgo de readmisión como el costo de la internación y la mortalidad.

Las presentes recomendaciones están dirigidas a:

(i) optimizar el cumplimiento de normas y la incorporación de hábitos en cada una de las fases de la cirugía, detectando factores de riesgo para infecciones del sitio quirúrgico potencialmente corregibles o modificables; y

(ii) adecuar la profilaxis antibiótica preoperatoria y el cuidado intra y postoperatorio.



– – –

July 9, 2017 at 3:50 pm

Validation of the diagnosis ‘prosthetic joint infection’ in the Danish Hip Arthroplasty Register

Rev. Bone & Joint Journal 2016 Vol. 98 N.3 P.320-325       

H. Gundtoft, A. B. Pedersen, H. C. Schønheyder, S. Overgaard



The purpose of this study was to validate the diagnosis of periprosthetic joint infection (PJI) in the Danish Hip Arthroplasty Register (DHR).

Patients and Methods

We identified a cohort of patients from the DHR who had undergone primary total hip arthroplasty (THA) since 1 January 2005 and followed them until first-time revision, death, emigration or until 31 December 2012. Revision for PJI, as registered in the DHR, was validated against a benchmark which included information from microbiology databases, prescription registers, clinical biochemistry registers and clinical records. We estimated the sensitivity, specificity, positive predictive value (PPV) and negative predictive value (NPV) for PJI in the DHR alone and in the DHR when combined with microbiology databases.


In total, 1382 of the 37 826 primary THAs in the DHR were registered as having been revised for any cause once 26 patients with errors in registration had been excluded: 232 of these were for PJI. For this group, the sensitivity was 67%, specificity 95%, PPV 77%, and NPV 92%. Combining the data from the DHR with those from microbiology databases increased the sensitivity to 90% and also improved specificity (100%), PPV (98%) and NPV (98%).


Only two thirds of revisions for PJI were captured in the DHR and only 77% of the PJI reported to the DHR could be confirmed to be infected. Take home message: combining the data from the DHR with those from microbiology databases substantially improved the validity of the diagnosis of PJI and should enable future register-based studies.



July 6, 2017 at 8:46 am

Managing uncertainty – a qualitative study of surgeons’ decision-making for one-stage and two-stage revision surgery for prosthetic hip joint infection

Rev. BMC Musculoskeletal Disorders 2017 V.18 N.4 P.154

Andrew J. Moore, Ashley W. Blom, Michael R. Whitehouse and Rachael Gooberman-Hill

1 School of Clinical Sciences, University of Bristol, Bristol, UK.

2 School of Clinical Sciences, University of Bristol, Bristol, UK.



Approximately 88,000 primary hip replacements are performed in England and Wales each year. Around 1% go on to develop deep prosthetic joint infection.

Between one-stage and two-stage revision arthroplasty best treatment options remain unclear.

Our aims were to characterise consultant orthopaedic surgeons’ decisions about performing either one-stage or two-stage revision surgery for patients with deep prosthetic infection (PJI) after hip arthroplasty, and to identify whether a randomised trial comparing one-stage with two-stage revision would be feasible.


Semi-structured interviews were conducted with 12 consultant surgeons who perform revision surgery for PJI after hip arthroplasty at 5 high-volume National Health Service (NHS) orthopaedic departments in England and Wales. Surgeons were interviewed before the development of a multicentre randomised controlled trial. Data were analysed using a thematic approach.


There is no single standardised surgical intervention for the treatment of PJI. Surgeons balance multiple factors when choosing a surgical strategy which include multiple patient-related factors, their own knowledge and expertise, available infrastructure and the infecting organism. Surgeons questioned whether it was appropriate that the two-stage revision remained the best treatment, and some surgeons’ willingness to consider more one-stage revisions had increased over recent years and were influenced by growing evidence showing equivalence between surgical techniques, and local observations of successful one-stage revisions. Custom-made articulating spacers was a practice that enabled uncertainty to be managed in the absence of definitive evidence about the superiority of one surgical technique over the other. Surgeons highlighted the need for research evidence to inform practice and thought that a randomised trial to compare treatments was needed. Most surgeons thought that patients who they treated would be eligible for trial participation in instances where there was uncertainty about the best treatment option.


Surgeons highlighted the need for evidence to support their choice of revision. Some surgeons’ willingness to consider one-stage revision for infection had increased over time, largely influenced by evidence of successful one-stage revisions.

Custom-made articulating spacers also enabled surgeons to manage uncertainty about the superiority of surgical techniques.

Surgeons thought that a prospective randomised controlled trial comparing one-stage with two-stage joint replacement is needed and that randomisation would be feasible.


July 6, 2017 at 8:45 am

Intraoperative diagnosis of Staphylococcus aureus and coagulase-negative Staphylococcus using Xpert MRSA/SA SSTI assay in prosthetic joint infection.

Rev. New Microbiologica 2017 V.40 N.2 P.130-134

Sambri, A.; Pignatti, G.; Romagnoli, M.; Donati, D.; Marcacci, M.; Cadossi, M.

Istituto Ortopedico Rizzoli, Bologna, Italy.


The aim of this prospective study was to evaluate the performance of the Polymerase Chain Reaction (PCR) tool Xpert MRSA/SA SSTI test (Cepheid, Sunnyvale, CA, USA) on periprosthetic samples from a cohort of patients with suspected prosthetic joint infection (PJI).

Seventy adult patients were included in this prospective study. On the basis of the preoperative evaluation, 39 patients were clinically considered to have a PJI, whereas 31 were presumed to suffer from an aseptic mobilization of the implant. Xpert MRSA/SA SSTI identified 4 out of 4 MRSA, 7 out of 7 MSSA, and 14 out of 16 methicillin resistant CoNS.

Among the 31 patients not having a PJI, the rapid PCR did not find any bacteria among those identifiable, thus demonstrating an excellent performance in terms of specificity.

Statistical analysis of the analytical performance showed a high correlation (p<0.001) between the result of Xpert MRSA/SA SSTI and culture.

Xpert MRSA/SA SSTI assay is a novel, yet well known, rapid and accurate method for the identification of different species of staphylococci.

The test can be used with peri-operative samples thus dramatically improving the diagnostic sensitivity. In addition, thanks to the very short turnaround time the use of Xpert assay can modify the clinical management of patients suffering from PJI during the ongoing operative procedure.


July 6, 2017 at 8:43 am

Primary cervical osteomyelitis.

J Chin Med Assoc. 2013 Nov;76(11):640-7.

Tsai CE1, Lee FT, Chang MC, Yu WK, Wang ST, Liu CL.



Cervical osteomyelitis accounts for only 3-11% of all cases of spinal osteomyelitis, and the diagnosis may be delayed. The characteristics of different pathogens causing cervical osteomyelitis are not fully understood, and there are few established guidelines for treatment.


The cases of six patients who presented with primary cervical osteomyelitis in the orthopedic department between January 2002 and March 2012 were retrospectively reviewed. All patients had been treated with anterior decompression, instrumentation, and autograft fusion. Data about preoperative and postoperative symptoms, neurological function, pain, C-reactive protein (CRP) levels, and the results of plain film and magnetic resonance imaging were reviewed.


Intraoperative cultures revealed Staphylococcus aureus in three patients, Propionibacterium acnes in two, and Mycobacterium tuberculosis in one. The mean duration between symptoms and diagnosis was 7.2 weeks (range, 3-12 weeks). Three patients with S. aureus infections had relatively higher preoperative CRP levels (mean, 173 mg/L) than did the patients with P. acnes infections or tuberculosis (mean, 5.5 mg/L). However, bony destruction was less severe in patients with S. aureus infections than in those patients with P. acnes and tuberculosis. All CRP levels returned to normal in 12 weeks, and all six patients had a final stable cervical alignment and fusion. Ultimately, neurological function and pain score improved in all patients.


Cervical osteomyelitis caused by S. aureus has an acute onset, higher CRP level, shorter duration from onset to diagnosis and thus causes less bony destruction. By contrast, cervical osteomyelitis caused by P. acnes and tuberculosis has an indolent course, a low or even normal CRP level, a longer duration from onset to diagnosis, and produces more severe bony destruction. Anterior decompression, instrumentation, and autograft fusion can be successfully used to treat primary cervical osteomyelitis. However, a mesh cage can also be a good alternative to an autograft.


July 3, 2017 at 3:21 pm

The role of biomarkers in the diagnosis of periprosthetic joint infection.

EFORT Open Rev. 2017 Mar 13;1(7):275-278.

Shahi A1, Parvizi J1.

Author information

1 The Rothman Institute at Thomas Jefferson University, Philadelphia, USA.


The role of serum erythrocyte sedimentation rate (ESR) and C-reactive protein (CRP) as the first line for evaluating a patient with periprosthetic joint infection (PJI) has been debunked.We are living in the era of biomarkers for the diagnosis of PJI, and to that effect, several biomarkers have been introduced such as synovial fluid alpha defensin and leukocyte esterase.The synovial fluid leukocyte esterase test has a low cost, is accessible, and has provided promising results for diagnosing PJI.There is an urgent need for an accurate and reliable serum biomarker for diagnosing patients with PJI. Cite this article: Shahi A, Parvizi J. The role of biomarkers in the diagnosis of periprosthetic joint infection.


June 30, 2017 at 12:01 pm

Older Posts


July 2017
« Jun    

Posts by Month

Posts by Category