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Open Forum Infectious Diseases May 2024Implant sonication is useful for recovery of periprosthetic joint infection (PJI) pathogens in culture, but exact cutoff points for definition of clinically significant...
INTRODUCTION
Implant sonication is useful for recovery of periprosthetic joint infection (PJI) pathogens in culture, but exact cutoff points for definition of clinically significant sonicate fluid culture results vary from study to study. The aim of this study was to define ideal sonicate fluid culture cutoff points for PJI diagnosis.
METHODS
Sonicate fluid cultures from hip and knee prosthesis components removed between February 2007 and December 2020 were studied. Prosthesis components were placed in solid containers in the operating room; in the clinical microbiology laboratory, 400 mL Ringer's solution was added, and containers subjected to vortexing, sonication and then vortexing, followed by centrifugation. Concentrated sonicate fluid was plated on aerobic and anaerobic solid media, and culture results reported semiquantitatively, as no growth, <20, 20-50, 51-100, or >100 CFU/10 mL sonicate fluid. Sonicate cultures from cement spacers and cultures yielding more than 1 microorganism were excluded. Sensitivity and specificity of each cutoff point was evaluated.
RESULTS
A total of 1448 sonicate fluid cultures were evaluated, 68% from knees and 32% from hips. PJI was present in 644 (44%) cases. Sensitivity of sonicate culture was 75.0% at <20 CFU/10 mL, 55.3% at ≥20 CFU/10 mL, 46.9% at >51 CFU/10 mL, and 39.8% at >100 CFU/10 mL. Specificity was 78.2%, 99.8%, 100%, and 100%, at the 4 cutoff points, respectively.
CONCLUSIONS
A cutoff point for sonicate fluid culture positivity of ≥20 CFU/10 mL is suitable for PJI diagnosis.
PubMed: 38715572
DOI: 10.1093/ofid/ofae159 -
Emerging Infectious Diseases May 2024To determine changes in Bordetella pertussis and B. parapertussis detection rates, we analyzed 1.43 million respiratory multiplex PCR test results from US facilities...
To determine changes in Bordetella pertussis and B. parapertussis detection rates, we analyzed 1.43 million respiratory multiplex PCR test results from US facilities from 2019 through mid-2023. From mid-2022 through mid-2023, Bordetella spp. detection increased 8.5-fold; 95% of detections were B. parapertussis. While B. parapertussis rates increased, B. pertussis rates decreased.
Topics: Bordetella parapertussis; United States; Humans; Bordetella Infections; Communicable Diseases, Emerging; Bordetella pertussis; History, 21st Century; Child; Child, Preschool; Whooping Cough; Adult; Adolescent; Infant; Multiplex Polymerase Chain Reaction; Young Adult
PubMed: 38666607
DOI: 10.3201/eid3005.231278 -
Vaccines Feb 2024Pertussis, or whooping cough, is a global public health concern. Pertussis vaccines have demonstrated good protection against infections, but their effectiveness... (Review)
Review
BACKGROUND
Pertussis, or whooping cough, is a global public health concern. Pertussis vaccines have demonstrated good protection against infections, but their effectiveness against remains debated due to conflicting study outcomes.
METHODS
A systematic review and meta-analysis were conducted to assess the effectiveness of pertussis vaccines in protecting children against infection. A comprehensive search of PubMed, Web of Science, and Scopus databases was conducted, and randomized controlled trials (RCTs) and observational studies that met inclusion criteria were included in the analysis.
RESULTS
The meta-analysis, involving 46,533 participants, revealed no significant protective effect of pertussis vaccination against infection (risk ratio: 1.10, 95% confidence interval: 0.83 to 1.44). Subgroup analyses by vaccine type and study design revealed no significant protection. The dearth of recent data and a limited pool of eligible studies, particularly RCTs, underscore a critical gap that warrants future research in the domain.
CONCLUSIONS
These findings offer crucial insights into the lack of effectiveness of pertussis vaccines against . Given the rising incidence of cases and outbreaks, coupled with the lack of cross-protection by the existing vaccines, there is an urgent need to develop vaccines that include specific antigens to protect against .
PubMed: 38543887
DOI: 10.3390/vaccines12030253 -
Proceedings (Baylor University. Medical... 2024Stevens-Johnson syndrome and toxic epidermal necrolysis are potentially life-threatening cutaneous diseases that are rarely seen in the pediatric population. We describe...
Stevens-Johnson syndrome and toxic epidermal necrolysis are potentially life-threatening cutaneous diseases that are rarely seen in the pediatric population. We describe a case of a 7-year-old female who presented with fever, cough, mucosal erosions, and a widespread maculopapular eruption with flaccid bullae for 4 days. She had no sick contacts and no new medications, supplements, or vitamins. She then rapidly developed ulcerations in her oral mucosa and genital area, numerous scattered tense bullae throughout her body, and patchy areas of desquamation. Infectious disease workup revealed positivity only for and she was subsequently diagnosed with idiopathic toxic epidermal necrolysis.
PubMed: 38343491
DOI: 10.1080/08998280.2024.2301782 -
Antimicrobial Agents and Chemotherapy Feb 2024The growing threat of antibiotic-resistant bacterial pathogens necessitates the development of alternative antimicrobial approaches. This is particularly true for...
The growing threat of antibiotic-resistant bacterial pathogens necessitates the development of alternative antimicrobial approaches. This is particularly true for chronic wound infections, which commonly harbor biofilm-dwelling bacteria. A novel electrochemical bandage (e-bandage) delivering low-levels of hypochlorous acid (HOCl) was evaluated against murine wound biofilms. 5 mm skin wounds were created on the dorsum of mice and infected with 10 colony-forming units (CFU) of . Biofilms were formed over 2 days, after which e-bandages were placed on the wound beds and covered with Tegaderm. Mice were administered Tegaderm-only (control), non-polarized e-bandage (no HOCl production), or polarized e-bandage (using an HOCl-producing potentiostat), with or without systemic amikacin. Purulence and wound areas were measured before and after treatment. After 48 hours, wounds were harvested for bacterial quantification. Forty-eight hours of polarized e-bandage treatment resulted in mean biofilm reductions of 1.4 log CFUs/g ( = 0.0107) vs non-polarized controls and 2.2 log CFU/g ( = 0.004) vs Tegaderm-only controls. Amikacin improved CFU reduction in Tegaderm-only ( = 0.0045) and non-polarized control groups ( = 0.0312) but not in the polarized group ( = 0.3876). Compared to the Tegaderm-only group, there was less purulence in the polarized group ( = 0.009). Wound closure was neither impeded nor improved by either polarized or non-polarized e-bandage treatment. Concurrent amikacin did not impact wound closure or purulence. In conclusion, an HOCl-producing e-bandage reduced in wound biofilms with no impairment in wound healing, representing a promising antibiotic-free approach for addressing wound infection.
Topics: Animals; Mice; Pseudomonas aeruginosa; Hypochlorous Acid; Amikacin; Pseudomonas Infections; Wound Infection; Bandages; Anti-Bacterial Agents; Biofilms
PubMed: 38214514
DOI: 10.1128/aac.01216-23 -
Germs Jun 2023is a rare cause of hemorrhagic bronchopneumonia. Important to the clinician is a clear understanding that the treatment of this rare organism differs greatly from the...
INTRODUCTION
is a rare cause of hemorrhagic bronchopneumonia. Important to the clinician is a clear understanding that the treatment of this rare organism differs greatly from the successful antibiotic treatment of the more common species, and .
CASE REPORT
A 64-year-old female presented to the emergency department after experiencing one week of worsening hemoptysis. Upon admission, she was afebrile and all initial laboratory test results were normal. Bronchoalveolar hemorrhage suggested by radiographic imaging was confirmed by bronchoscopy. Bronchoalveolar lavage (BAL) cultures contained unspeciated . Rapid worsening of the hemoptysis led to intubation and the decision to perform bronchial artery embolization. However, the intensity of the hemoptysis persisted. Septic shock ensued despite treatment with broad spectrum antibiotics including azithromycin, vancomycin, and cefepime. The microbiological speciation results finalized shortly after the patient's death. The identified organism was .
CONCLUSIONS
Although macrolide antibiotics are first line treatment for and , macrolide antibiotics are generally not effective against . Clinical suspicion of infection should prompt consideration of alternative antibiotics known to be effective against this rare species, including carbapenems and fluoroquinolones. The use of these latter antibiotics may advisably be considered as an empirical treatment during the delay of microbiological speciation.
PubMed: 38144244
DOI: 10.18683/germs.2023.1381 -
Open Forum Infectious Diseases Dec 2023Shotgun and targeted metagenomic sequencing have been shown in separate studies to be potentially useful for culture-free pathogen identification in blood and/or plasma...
BACKGROUND
Shotgun and targeted metagenomic sequencing have been shown in separate studies to be potentially useful for culture-free pathogen identification in blood and/or plasma of patients with infective endocarditis (IE). However, the 2 approaches have not been directly compared. The aim of this study was to compare shotgun metagenomic sequencing with targeted metagenomic sequencing (tMGS) for organism identification in blood or plasma of patients with IE.
METHODS
Patients with possible or definite IE were prospectively enrolled from October 2020 to July 2021. Shotgun metagenomic sequencing was performed with the Karius test, which uses microbial cell-free DNA (mcfDNA) sequencing to detect, identify, and quantitate DNA-based pathogens in plasma. tMGS was performed using a 16S ribosomal RNA (rRNA) polymerase chain reaction assay targeting the V1 to V3 regions of the 16S rRNA gene. Results were compared using the McNemar test of paired proportions.
RESULTS
Samples from 34 patients were investigated. The Karius test was positive in 24/34 (71%), including 3/6 (50%) with blood culture-negative endocarditis (BCNE), which was not significantly different from the positivity rate of tMGS ( = .41). Results of the Karius test were concordant with tMGS in 75% of cases. The Karius test detected 2 cases of methicillin-resistant among the 7 detections, in accordance with results of phenotypic susceptibility testing. The combination of blood cultures, the Karius test, and tMGS found a potential causative pathogen in 33/34 (97%), including 5/6 with BCNE.
CONCLUSIONS
The Karius test and tMGS yielded comparable detection rates; however, beyond organism identification, the Karius test generated potentially useful antibiotic resistance data.
PubMed: 38075017
DOI: 10.1093/ofid/ofad546 -
Microbiology Resource Announcements Jan 2024Here, we report the complete genome of strain 400431-b isolated from a nasopharyngeal swab from a 4-year-old patient presenting with a protracted course of whooping...
Here, we report the complete genome of strain 400431-b isolated from a nasopharyngeal swab from a 4-year-old patient presenting with a protracted course of whooping cough, vaccinated with three doses of diphtheria-tetanus-acellular pertussis-hepatitis B-poliomyelitis- type b vaccine.
PubMed: 38018846
DOI: 10.1128/MRA.00976-23 -
PloS One 2023B. parapertussis is one of the etiological agents of whooping cough. Once inhaled, the bacteria bind to the respiratory epithelium and start the infection. Little is...
B. parapertussis is one of the etiological agents of whooping cough. Once inhaled, the bacteria bind to the respiratory epithelium and start the infection. Little is known about this first step of host colonization and the role of the human airway epithelial barrier on B. parapertussis infection. We here investigated the outcome of the interaction of B. parapertussis with a polarized monolayer of respiratory epithelial cells. Our results show that B. parapertussis preferentially attaches to the intercellular boundaries, and causes the disruption of the tight junction integrity through the action of adenylate cyclase toxin (CyaA). We further found evidence indicating that this disruption enables the bacterial access to components of the basolateral membrane of epithelial cells to which B. parapertussis efficiently attaches and gains access to the intracellular location, where it can survive and eventually spread back into the extracellular environment. Altogether, these results suggest that the adenylate cyclase toxin enables B. parapertussis to overcome the epithelial barrier and eventually establish a niche of persistence within the respiratory epithelial cells.
Topics: Humans; Bordetella parapertussis; Adenylate Cyclase Toxin; Bordetella pertussis; Intracellular Space; Whooping Cough; Epithelial Cells
PubMed: 38011105
DOI: 10.1371/journal.pone.0291331 -
Journal of Clinical Microbiology Dec 2023Standardized approaches to phage susceptibility testing (PST) are essential to inform selection of phages for study in patients with bacterial infections. There is no...
Standardized approaches to phage susceptibility testing (PST) are essential to inform selection of phages for study in patients with bacterial infections. There is no reference standard for assessing bacterial susceptibility to phage. We compared agreement between PST performed at three centers: two centers using a liquid assay standardized between the sites with the third, a plaque assay. Four phages: PaWRA01ø11 (EPa11), PaWRA01ø39 (EPa39), PaWRA02ø83 (EPa83), PaWRA02ø87 (EPa87), and a cocktail of all four phages were tested against 145 . isolates. Comparisons were made within measurements at the two sites performing the liquid assay and between these two sites. Agreement was assessed based on coverage probability (CP), total deviation index, concordance correlation coefficient (CCC), measurement accuracy, and precision. For the liquid assay, there was satisfactory agreement among triplicate measurements made on different days at site 1, and high agreement based on accuracy and precision between duplicate measurements made on the same run at site 2. There was fair accuracy between measurements of the two sites performing the liquid assay, with CCCs below 0.6 for all phages tested. When compared to the plaque assay (performed once at site 3), there was less agreement between results of the liquid and plaque assays than between the two sites performing the liquid assay. Similar findings to the larger group were noted in the subset of 46 . isolates from cystic fibrosis. Results of this study suggest that reproducibility of PST methods needs further development.
Topics: Humans; Bacteriophages; Pseudomonas aeruginosa; Reproducibility of Results; Pseudomonas Infections; Cystic Fibrosis; Anti-Bacterial Agents
PubMed: 37962552
DOI: 10.1128/jcm.00614-23