ABSTRACTKocuria rhizophila, a Gram-positive coccus, is usually regarded as a contaminant. It has been described in catheter device–related infections in children, but never as being involved in ...central nervous system infections. We report here for the first time a case of ventriculoperitonitis due to K. rhizophila in adult, identified by MALDI-TOF mass spectrometry and 16S rRNA gene sequencing.
The major virulence factors of Clostridioides difficile (C. difficile) are enterotoxins A (TcdA) and B (TcdB). The study of toxins is a crucial step in exploring the virulence of this pathogen. ...Currently, the toxin purification process is either laborious and time-consuming in C. difficile or performed in heterologous hosts. Therefore, we propose a streamlined method to obtain functional toxins in C. difficile. Two C. difficile strains were generated, each harboring a sequence encoding a His-tag at the 3′ end of C. difficile 630∆erm tcdA or tcdB genes. Each toxin gene is expressed using the Psub.tet promoter, which is inducible by anhydro-tetracycline. The obtained purification yields were 0.28 mg and 0.1 mg per liter for rTcdA and rTcdB, respectively. In this study, we successfully developed a simple routine method that allows the production and purification of biologically active rTcdA and rTcdB toxins with similar activities compared to native toxins.
Invasive cardiovascular infections by
Mycobacterium chimaera
associated with open-heart surgery have been reported worldwide since 2013. Here, we report a case of a 61 year old man, without any other ...particular medical background, who underwent cardiac surgery for replacing part of the ascending aorta by a bio-prosthetic graft. Eighteen months later, the patient was painful at the lower back with fever. A pyogenic vertebral osteomyelitis due to
M. chimaera
associated to graft infection was diagnosed after 6 months of sub-acute infection. The patient presented a disseminated disease with cerebral lesions, chorioretinitis, and chronic renal failure. Despite adequate antimicrobial treatment and graft explantation, the patient died after 6 years. We reviewed the literature on
M. chimaera
infections associated with open-heart surgery. The worldwide outbreak has been explained by airborne bioaerosol generated by the 3T heater–cooler unit (HCU) used during cardiac by-pass surgical procedures. These infections are difficult to diagnose because of a long latency period (up to several years), with no specific symptoms and a highly specialized microbiological diagnosis. The treatment is based on antibiotics and surgery. These infections are also difficult to treat, since the mortality rate is high around 50%. Prevention is necessary by modifying the use of HCUs in operating rooms.
To evaluate performances of the rapid multiplex PCR assay BioFire FilmArray Pneumonia Panel (FA-PP) for detection of bacterial pathogens and antibiotic resistance genes in sputum, endotracheal ...aspirate (ETA) and bronchoalveolar lavage (BAL) specimens.
This prospective observational study was conducted in 11 French university hospitals (July to December 2018) and assessed performance of FA-PP by comparison with routine conventional methods.
A total of 515 respiratory specimens were studied, including 58 sputa, 217 ETA and 240 BAL. The FA-PP detected at least one pathogen in 384 specimens, yielding an overall positivity rate of 74.6% (384/515). Of them, 353 (68.5%) specimens were positive for typical bacteria while eight atypical bacteria and 42 resistance genes were found. While identifying most bacterial pathogens isolated by culture (374/396, 94.4%), the FA-PP detected 294 additional species in 37.7% (194/515) of specimens. The FA-PP demonstrated positive percentage agreement and negative percentage agreement values of 94.4% (95% CI 91.7%–96.5%) and 96.0% (95% CI 95.5%–96.4%), respectively, when compared with culture. Of FA-PP false-negative results, 67.6% (46/68) corresponded to bacterial species not included in the panel. At the same semi-quantification level (in DNA copies/mL for FA-PP versus in CFU/mL for culture), the concordance rate was 43.4% (142/327) for culture-positive specimens with FA-PP reporting higher semi-quantification of ≥1 log10 in 48.6% (159/327) of cases. Interestingly, 90.1% of detected bacteria with ≥106 DNA copies/mL grew significantly in culture.
FA-PP is a simple and rapid molecular test that could complement routine conventional methods for improvement of diagnosis accuracy of pneumonia.
Bartter syndrome is a severe inherited tubulopathy characterized at birth by salt wasting, severe polyuria, dehydration, growth retardation and secondary hyperaldosteronism. Prenatally, the disease ...is usually discovered following onset of severe polyhydramnios. We studied amniotic fluid aldosterone concentration in cases of Bartter syndrome and in control groups. Amniotic fluid aldosterone was assayed by radioimmunoassay. We undertook a retrospective case-control study based on 36 cases of postnatally diagnosed Bartter syndrome and 144 controls matched for gestational age. Two controls groups were defined: controls with polyhydramnios (n=72) and control without polyhydramnios (n=72). Amniotic fluid aldosterone was compared between the three groups. The median amniotic fluid aldosterone concentration in the Bartter syndrome group (90 pg/mL) did not differ significantly from that in the controls with polyhydramnios (90 pg/mL, p=0.33) or the controls without polyhydramnios (87 pg/mL, p=0.41). In conclusion, amniotic fluid aldosterone assay cannot be used for prenatal diagnosis of Bartter syndrome.
To describe the epidemiology of Klebsiella spp. meningitis in France with respect to clinical and bacteriological data.
We performed a four-year multicenter, retrospective, observational study. The ...primary objective was to provide a clinical description of patients with Klebsiella spp. meningitis. Secondary objectives were to compare community-acquired meningitis and healthcare-associated meningitis and to analyze factors associated with mortality.
We enrolled 131 patients with Klebsiella spp. meningitis. Eighty-two (62.6%) infections were reported following neurosurgery. Twenty-eight strains (21.4%) were resistant to third-generation cephalosporins (3GC). The median IQR cellularity was 980/mm
116-5550, the median protein level was 5.67 1.62-9 g/L and the median CSF glucose level was 2.5 0-3.4 mmol/L. The in-hospital mortality rate was 23.6%. Community-acquired meningitis isolates were more frequently susceptible to 3GC than isolates from healthcare-associated meningitis (89.2% versus 72%; P=0.04). Comorbidities reported for patients with community-acquired meningitis were mainly diabetes mellitus and liver cirrhosis. In multivariate analysis, focal neurological disorder at the time of diagnosis was the only factor associated with in-hospital mortality (P=0.01).
Purulent meningitis caused by Klebsiella spp. needs to be considered in patients with community-acquired meningitis and preexisting conditions, as well as in case of meningitis following neurosurgical procedures.
OBJECTIVEThe Bacterial Meningitis Score (BMS) is recommended by pediatric academic societies to rule out the diagnosis of bacterial meningitis. The aim of this study was to evaluate the performance ...of the BMS to identify adults at no risk for bacterial meningitis.
METHODSWe conducted a multicentric retrospective study including adults who consulted the emergency department (ED) for meningitis cerebrospinal fluid (CSF) white blood cells ≥5/mm with a ratio of white blood cells/red blood cells <1:900) during a 4-year period. The BMS variables wereCSF positive Gram stain, CSF absolute neutrophil count ≥1000 cells/μL, CSF protein ≥80 mg/dL, peripheral blood absolute neutrophil count ≥10 000 cells/μL, and seizures. Bacterial meningitis was defined for patients who had a lumbar puncture with CSF pleocytosis and positive bacterial analysis of CSF. The primary endpoint was the sensitivity of the BMS to rule out bacterial meningitis in adults. The secondary outcome was to assess the rate of patients for whom antibiotics could have been avoided using the BMS and the diagnostic performance of procalcitonin in patients with a BMS ≥1.
RESULTSOf 930 patients with meningitis, 626 were included in the analysis, and 27 (4.3%) were diagnosed with bacterial meningitis. A total of 384/626 (61.3%) patients had a BMS = 0, and none presented bacterial meningitis. BMS sensitivity was 100% 95% confidence interval (CI), 87.2–100%, and its negative predictive values were 100% (95% CI, 98.8–100%).
CONCLUSIONAmong patients with a diagnosis of meningitis in ED, a BMS of 0 may safely rule out bacterial meningitis.
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