Recurrent Clostridioides difficile infection (rCDI) often occurs after standard-of-care antibiotics. VOWST oral spores (VOS, previously SER-109), an FDA-approved orally administered microbiome therapeutic, is indicated to prevent rCDI following antibiotics for rCDI. To evaluate safety and efficacy of VOS from two phase 3 trials, (randomized, placebo-controlled [ECOSPOR III: NCT03183128] and open-label, single arm [ECOSPOR IV: NCT03183141]) of 349 adults with rCDI and prevalent comorbidities. VOS or placebo [ECOSPOR III only] (4 capsules once daily for 3 days). Integrated analysis of treatment-emergent adverse events (TEAEs) collected through week 8; serious TEAEs and TEAEs of special interest collected through week 24; and rates of rCDI (toxin-positive diarrhea requiring treatment) evaluated through weeks 8 and 24. TEAEs were mostly mild or moderate and gastrointestinal. Most common treatment-related TEAEs were flatulence, abdominal pain and distension, fatigue, and diarrhea. There were 11 deaths (3.2
Bile acids (BAs) are steroid detergents in bile that contribute to the absorption of fats and fat-soluble vitamins while shaping the gut microbiome because of their antimicrobial properties1-4. Here we identify the enzyme responsible for a mechanism of BA metabolism by the gut microbiota involving amino acid conjugation to the acyl-site of BAs, thus producing a diverse suite of microbially conjugated bile acids (MCBAs). We show that this transformation is mediated by acyltransferase activity of bile salt hydrolase (bile salt hydrolase/transferase, BSH/T). Clostridium perfringens BSH/T rapidly performed acyl transfer when provided various amino acids and taurocholate, glycocholate or cholate, with an optimum at pH 5.3. Amino acid conjugation by C. perfringens BSH/T was diverse, including all proteinaceous amino acids except proline and aspartate. MCBA production was widespread among gut bacteria, with strain-specific amino acid use. Species with similar BSH/T amino acid sequences had similar conjugation profiles and several bsh/t alleles correlated with increased conjugation diversity. Tertiary structure mapping of BSH/T followed by mutagenesis experiments showed that active site structure affects amino acid selectivity. These MCBA products had antimicrobial properties, where greater amino acid hydrophobicity showed greater antimicrobial activity. Inhibitory concentrations of MCBAs reached those measured natively in the mammalian gut. MCBAs fed to mice entered enterohepatic circulation, in which liver and gallbladder concentrations varied depending on the conjugated amino acid. Quantifying MCBAs in human faecal samples showed that they reach concentrations equal to or greater than secondary and primary BAs and were reduced after bariatric surgery, thus supporting MCBAs as a significant component of the BA pool that can be altered by changes in gastrointestinal physiology. In conclusion, the inherent acyltransferase activity of BSH/T greatly diversifies BA chemistry, creating a set of previously underappreciated metabolites with the potential to affect the microbiome and human health.
This prospective observational study aimed to evaluate the association of metabolomic alterations with weight loss outcomes following sleeve gastrectomy (SG). We evaluated the metabolomic profile of serum and feces prior to SG and three months post-SG, along with weight loss outcomes in 45 adults with obesity. The percent total weight loss for the highest versus the lowest weight loss tertiles (T3 vs. T1) was 17.0 ± 1.3% and 11.1 ± 0.8%, p < 0.001. Serum metabolite alterations specific to T3 at three months included a decrease in methionine sulfoxide concentration as well as alterations to tryptophan and methionine metabolism (p < 0.03). Fecal metabolite changes specific to T3 included a decrease in taurine concentration and perturbations to arachidonic acid metabolism, and taurine and hypotaurine metabolism (p < 0.002). Preoperative metabolites were found to be highly predictive of weight loss outcomes in machine learning algorithms, with an average area under the curve of 94.6% for serum and 93.4% for feces. This comprehensive metabolomics analysis of weight loss outcome differences post-SG highlights specific metabolic alterations as well as machine learning algorithms predictive of weight loss. These findings could contribute to the development of novel therapeutic targets to enhance weight loss outcomes after SG.
BACKGROUND:Vancomycin is associated with potential nephrotoxicity and trough concentrations need to be monitored in certain patients. Falsely decreased vancomycin measurement may result in overtreatment and need to be identified promptly by clinicians and pharmacists to avoid toxicities.METHODS AND RESULTS:We report a case of rheumatoid factor-mediated falsely low vancomycin measurement with Abbott particle-enhanced turbidimetric inhibition immunoassay (PETINIA) method. Reanalyzing the sample using an alternative method, removing the interferences using heterophile blocking reagent as well as rheumatoid factor clean-up solution all helped to solve the false results. Results from alternative method and interference studies showed vancomycin concentrations reached toxic concentrations in the patient and administration of the drug was immediately terminated. The patient experienced a transient increase in serum creatinine.CONCLUSIONS:Even though most modern immunoassays use blocking agents to neutralize interfering antibodies such as rheumatoid factor, it is important for health care professionals to understand that occasional interference still occurs due to the heterogeneous nature of rheumatoid factor.
Varicella-zoster virus (VZV) is the etiologic agent of varicella (chickenpox) and herpes zoster (shingles) infections commonly involving skin, mucous membranes, and less frequently the central nervous system. Traditional methods for the laboratory diagnosis of these infections are time-consuming, labor-intensive, and often insensitive. ABSTRACT Varicella-zoster virus (VZV) is the etiologic agent of varicella (chickenpox) and herpes zoster (shingles) infections commonly involving skin, mucous membranes, and less frequently the central nervous system. Traditional methods for the laboratory diagnosis of these infections are time-consuming, labor-intensive, and often insensitive. As such, these tests are being replaced by more sensitive and rapid molecular methods. This study evaluated the performance of two different molecular assays, the Simplexa VZV Direct and Simplexa VZV Swab Direct, to detect VZV DNA in cerebrospinal fluid (CSF) and lesion-swab specimens, respectively. The Simplexa VZV Direct and Simplexa VZV Swab Direct assays were compared against individual composite reference methods that varied depending on the sample cohort examined. A total of 883 CSF and 452 cutaneous and mucocutaneous prospective, retrospective, and contrived specimens were evaluated in this multicenter study. The results of this study showed that the Simplexa assays demonstrated near perfect agreement (k = 0.98) compared to the composite reference methods for the detection of VZV in CSF and lesion swab specimens. A further comparison between the standard of care molecular assays employed at the site of specimen collection and the Simplexa assays demonstrated excellent agreement (k = 1.0). The Simplexa assays offer rapid and reliable alternatives for the detection of VZV in certain clinical specimens without the need for nucleic acid extraction.
In general, we agree with the comments and suggestions raised by Escandon and colleagues [1], and we are grateful to them for identifying the error discussed below. The limitations pointed out in their letter were raised in the Discussion section of our original article. The suggestions about sensitivity analysis, more comprehensive case definitions, and precise mask type during the relevant exposure are valid but unavoidable given the timing of the study relative to the start of the pandemic. None of the issues raised affect our conclusions regarding associations between seropositivity or asymptomatic rate and job grouping or mask use. Escandon et al correctly point out that the 30-day window for exhibiting symptoms prior to blood collection may have resulted in an overestimation of the asymptomatic rate in this study. Further analysis of the data revealed that 76 seropositive individuals indicated that they were previously diagnosed with coronavirus disease...
Group B Streptococcus (GBS) is the leading cause of neonatal sepsis and meningitis in developed countries. Recommendations for antepartum GBS detection include enriched culture with several options for identifying GBS, some of which are time-consuming. To reduce the time for identification and determination of the maternal GBS colonization status, rapid nucleic acid amplification technologies have been developed and commercialized. For rapid detection of GBS, a three-site clinical study was conducted to evaluate the NeuMoDx GBS assay, a real-time PCR test performed for vaginal/rectal swab specimens in Lim broth enrichment culture on the NeuMoDx 288 molecular system (NeuMoDx system); these data were used to a support 510(k) submission. A total of 1,250 eligible remnant samples were prospectively enrolled and tested during the study. The results of the PCR assay were compared to the results of the Centers for Disease Control and Prevention (CDC)-recommended enriched-culture method, which served as the gold standard reference method for the study. The NeuMoDx GBS assay results yielded a sensitivity of 96.9% (95% confidence interval [CI] = 94.1 to 98.4), specificity of 96.0% (95% CI = 94.6 to 97.1), and a total agreement with the reference method of 96.2% (95% CI = 93.8 to 98.3). NeuMoDx GBS assay results were also compared to results obtained using the BD MAX GBS assay on the BD MAX system. The two systems demonstrated a total percent agreement of 98.0% (95% CI = 95.5 to 100.0). The performance of the NeuMoDx GBS assay implemented on the NeuMoDx system compared favorably to the CDC enriched-culture method and to the BD MAX GBS assay.
Human metapneumovirus (hMPV) is an emerging pathogen well known to cause respiratory tract infections in children and adults. It is responsible for approximately 5% to 10% of all hospitalizations of children due to acute respiratory tract infections. The hMPV can cause severe illness in children, immunocompromised persons, and the elderly, which can progress to severe respiratory failure requiring hospitalization andmechanical ventilation. Transmission occurs via contact with contaminated respiratory secretions (droplet, aerosol). The hMPV is rarely known to cause central nervous system complications. Descriptions of this syndrome are limited to case reports, most of which have been in children. Reports suggest that this virus has been linked to diseases of the central nervous system including acute encephalopathy, encephalitis, and febrile seizures. Review of the literature revealed only one confirmed case of hMPV isolated from the cerebrospinal fluid of a patient with concurrent encephalitis. We describe an adult patient with acute meningoencephalitis associated with hMPV, in whom a respiratory virus panelwith polymerase chain reaction was positive for hMPVon nasopharyngeal swab, but was negative on the cerebrospinal fluid specimen.
Human metapneumovirus (hMPV) is an emerging pathogen well known to cause respiratory tract infections in children and adults. It is responsible for approximately 5% to 10% of all hospitalizations of children due to acute respiratory tract infections. The hMPV can cause severe illness in children, immunocompromised persons, and the elderly, which can progress to severe respiratory failure requiring hospitalization and mechanical ventilation. Transmission occurs via contact with contaminated respiratory secretions (droplet, aerosol). The hMPV is rarely known to cause central nervous system complications. Descriptions of this syndrome are limited to case reports, most of which have been in children. Reports suggest that this virus has been linked to diseases of the central nervous system including acute encephalopathy, encephalitis, and febrile seizures. Review of the literature revealed only one confirmed case of hMPV isolated from the cerebrospinal fluid of a patient with concurrent encephalitis. We describe an adult patient with acute meningoencephalitis associated with hMPV, in whom a respiratory virus panel with polymerase chain reaction was positive for hMPV on nasopharyngeal swab, but was negative on the cerebrospinal fluid specimen.
The management of infective endocarditis (IE) is very challenging in patients with blood cultures negative for a microorganism. Unfortunately, this situation is not uncommon, occurring in up to 30% of cases of IE. Precise microbiological diagnosis, however, is critical to optimize the antibiotic regimen, and thus, non-culture-based molecular techniques are playing a growing role in the care of these patients. We present a patient with culture-negative IE due to Haemophilus parainfluenzae, with the pathogen identified only via molecular techniques.
California serogroup viral infections are the most common reported etiology of arboviral encephalitis in the United States. Since 2002, only 29 cases have been reported in Michigan, mostly in children. We report a case of a 27-year-old woman presenting with vertigo and whose cerebrospinal fluid contained 14-3-3 protein.
Background: The association of vancomycin treatment failure with minimum inhibitory concentration (MIC) creep is concerning, as most isolates are still considered to be in the susceptible range. Several studies have suggested that the accessory gene regulator (agr) group II polymorphism is predictive of vancomycin treatment failure. We assessed the associations between increased vancomycin MIC, agr group II locus, and vancomycin treatment failure in Methicillin-resistant Staphylococcus aureus (MRSA) bacteremias.Methods: MRSA isolates from 99 inpatient bacteremias were studied. Susceptibility testing was conducted by an automated method (MicroScan) and by the gradient diffusion method (E-test). Vancomycin MICs were stratified into 3 groups for analysis: MIC <= 1, MIC > 1 but <= 2, and MIC > 2 mu g/mL. Strains were typed by repetitive-polymerase chain reaction analysis and the agr locus was identified by multiplex polymerase chain reaction. Failure of vancomycin treatment was defined as persistent bacteremia after 72 hours, death at 30 days, or treatment change due to clinical failure.Results: Among 99 bacteremic patients, there were 82 agr group II and 15 agr group I isolates. There was no relationship between higher vancomycin MICs and isolate agr II loci (42 of 82) (P = 0.59). Earlier vancomycin exposure was significantly associated with increased MIC (P = 0.03). Vancomycin treatment failure was observed in 12 patients: 3 required an alternate regimen, 4 had persistent positive cultures, and 5 whose deaths were attributable to MRSA infection. Survival in agr group II was 57 of 82 (69%) versus agr group I in which it was 14 of 15 (93%), (P = 0.06).Conclusions: We did not identify any significant association between MIC creep and vancomycin failure or between higher vancomycin MICs and agr group II. However, a higher mortality was seen in agr group II than agr group I.