Metagenomic next-generation sequencing (mNGS) is useful in the diagnosis of infectious disease. However, while it is highly sensitive at identifying bacteria, it does not provide information on the sensitivity of the organisms to antibiotics. The purpose of this study was to determine whether the results of mNGS can be used to guide optimization of culture methods to improve the sensitivity of culture from intraoperative samples. Between July 2014 and October 2019, patients with suspected joint infection (JI) from whom synovial fluid (SF) was obtained preoperatively were enrolled. Preoperative aspirated SF was analyzed by conventional microbial culture and mNGS. In addition to samples taken for conventional microbial culture, some samples were taken for intraoperative culture to optimize the culture method according to the preoperative mNGS results. The demographic characteristics, medical history, laboratory examination, mNGS, and culture results of the patients were recorded, and the possibility of the optimized culture methods improving diagnostic efficiency was evaluated.Aims
Methods
The aim of this study was to compare the results of 16S/28S rRNA sequencing with the erythrocyte sedimentation rate (ESR), C-reactive protein (CRP) level, and synovial fluid analysis in the diagnosis of prosthetic joint infection (PJI). Between September 2015 and August 2016, 214 consecutive patients were enrolled. In the study population, there were 25 patients with a PJI and 189 controls. Of the PJI patients, 14 (56%) were women, and the mean age at the time of diagnosis was 65 years (38 to 83). The ESR and CRP levels were measured, and synovial fluid specimens were collected prospectively. Synovial fluid was subjected to reverse transcription polymerase chain reaction (RT-PCR)/sequence analysis targeting the 16S/28S rRNA, and to conventional culture. Laboratory personnel who were blind to the clinical information performed all tests. The diagnosis of PJI was based on the criteria of the Musculoskeletal Infection Society.Aims
Patients and Methods
Positive cultures are not uncommon in cases of revision total
knee and hip arthroplasty (TKA and THA) for presumed aseptic causes.
The purpose of this study was to assess the incidence of positive
intra-operative cultures in presumed aseptic revision of TKA and
THA, and to determine whether the presence of intra-operative positive cultures
results in inferior survival in such cases. A retrospective cohort study was assembled with 679 patients
undergoing revision knee (340 cases) or hip arthroplasty (339 cases)
for presumed aseptic causes. For all patients three or more separate
intra-operative cultures were obtained. Patients were diagnosed
with a previously unsuspected prosthetic joint infection (PJI) if two
or more cultures were positive with the same organism. Records were
reviewed for demographic details, pre-operative laboratory results
and culture results. The primary outcome measure was infection-free
implant survival at two years.Aims
Patients and Methods
The purpose of this current multicentre study is to analyse the
presence of alpha-defensin proteins in synovial fluid using the
Synovasure lateral flow device and to determine its diagnostic reliability
and accuracy compared with the prosthetic joint infection (PJI)
criteria produced by the Musculoskeletal Infection Society (MSIS). A cohort of 121 patients comprising 85 total knee arthroplasties
and 36 total hip arthroplasties was prospectively evaluated between
May 2015 and June 2016 in three different orthopaedic centres. The
tests were performed on patients with a chronically painful prosthesis
undergoing a joint aspiration in a diagnostic pathway or during revision
surgery.Aims
Patients and Methods
Recently, several synovial biomarkers have been introduced into
the algorithm for the diagnosis of a prosthetic joint infection
(PJI). Alpha defensin is a promising biomarker, with a high sensitivity
and specificity, but it is expensive. Calprotectin is a protein
that is present in the cytoplasm of neutrophils, is released upon
neutrophil activation and exhibits anti-microbial activity. Our
aim, in this study, was to determine the diagnostic potential of
synovial calprotectin in the diagnosis of a PJI. In this pilot study, we prospectively collected synovial fluid
from the hip, knee, shoulder and elbow of 19 patients with a proven
PJI and from a control group of 42 patients who underwent revision
surgery without a PJI. PJI was diagnosed according to the current diagnostic criteria
of the Musculoskeletal Infection Society. Synovial fluid was centrifuged
and the supernatant was used to measure the level of calprotectin
after applying a lateral flow immunoassay. Aims
Patients and Methods
The diagnosis of periprosthetic joint infection (PJI) remains
demanding due to limitations of all the available diagnostic tests.
The synovial fluid marker, α-defensin, is a promising adjunct for
the assessment of potential PJI. The purpose of this study was to
investigate the qualitative assessment of α-defensin, using Synovasure
to detect or exclude periprosthetic infection in total joint arthroplasty. We studied 50 patients (28 women, 22 men, mean age 65 years;
20 to 89) with a clinical indication for revision arthroplasty who
met the inclusion criteria of this prospective diagnostic study.
The presence of α-defensin was determined using the qualitative
Synovasure test and compared with standard diagnostic methods for
PJI. Based on modified Musculoskeletal Infection Society (MSIS)
criteria, 13 cases were categorised as septic and 36 as aseptic revisions.
One test was inconclusive.Aims
Patients and Methods
The aim of our study was to describe the characteristics,
treatment, and outcomes of patients with periprosthetic joint infection
(PJI) and normal inflammatory markers after total knee arthroplasty
(TKA) and total hip arthroplasty (THA). In total 538 TKAs and 414 THAs underwent surgical treatment for
PJI and met the inclusion criteria. Pre-operative erythrocyte sedimentation
rate (ESR) and C-reactive protein level (CRP) were reviewed to identify
the seronegative cohort. An age- and gender-matched cohort was identified
from the remaining patients for comparison. Overall, 4% of confirmed
infections were seronegative (21 TKA and 17 THA). Of those who underwent
pre-operative aspiration, cultures were positive in 76% of TKAs
(n = 13) and 64% of THAs (n = 7). Cell count and differential were
suggestive of infection in 85% of TKA (n = 11) and all THA aspirates
(n = 5). The most common organism was coagulase-negative Cite this article:
Patients with infected arthroplasties are normally
treated with a two-stage exchange procedure using polymethylmethacrylate
bone cement spacers impregnated with antibiotics. However, spacers
may act as a foreign body to which micro-organisms may adhere and
grow. In this study it was hypothesised that subclinical infection may
be diagnosed with sonication of the surface biofilm of the spacer.
The aims were to assess the presence of subclinical infection through
sonication of the spacer at the time of a second-stage procedure,
and to determine the relationship between subclinical infection
and the clinical outcome. Of 55 patients studied, 11 (20%) were
diagnosed with subclinical infection. At a mean follow-up of 12
months (interquartile range 6 to 18), clinical failure was found in
18 (32.7%) patients. Of the patients previously diagnosed with subclinical
infection, 63% (7 of 11) had failed compared with 25% (11 of 44)
of those without subclinical infection (odds ratio 5.25, 95% confidence
interval 1.29 to 21.4, p = 0.021). Sonication of the biofilm of
the surface of the spacer is useful in order to exclude subclinical infection
and therefore contributes to improving the outcome after two-stage
procedures.
