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Multiple sclerosis is an autoimmune demyelinating disorder of the CNS, characterized by inflammatory lesions and an underlying neurodegenerative process, which is more prominent in patients with progressive disease course. It has been proposed that mitochondrial dysfunction underlies neuronal damage, the precise mechanism by which this occurs remains uncertain. To investigate potential mechanisms of neurodegeneration, we conducted a functional screening of mitochondria in neurons exposed to the CSF of multiple sclerosis patients with a relapsing remitting (n = 15) or a progressive (secondary, n = 15 or primary, n = 14) disease course. Live-imaging of CSF-treated neurons, using a fluorescent mitochondrial tracer, identified mitochondrial elongation as a unique effect induced by the CSF from progressive patients. These morphological changes were associated with decreased activity of mitochondrial complexes I, III and IV and correlated with axonal damage. The effect of CSF treatment on the morphology of mitochondria was characterized by phosphorylation of serine 637 on the dynamin-related protein DRP1, a post-translational modification responsible for unopposed mitochondrial fusion in response to low glucose conditions. The effect of neuronal treatment with CSF from progressive patients was heat stable, thereby prompting us to conduct an unbiased exploratory lipidomic study that identified specific ceramide species as differentially abundant in the CSF of progressive patients compared to relapsing remitting multiple sclerosis. Treatment of neurons with medium supplemented with ceramides, induced a time-dependent increase of the transcripts levels of specific glucose and lactate transporters, which functionally resulted in progressively increased glucose uptake from the medium. Thus ceramide levels in the CSF of patients with progressive multiple sclerosis not only impaired mitochondrial respiration but also decreased the bioavailability of glucose by increasing its uptake. Importantly the neurotoxic effect of CSF treatment could be rescued by exogenous supplementation with glucose or lactate, presumably to compensate the inefficient fuel utilization. Together these data suggest a condition of 'virtual hypoglycosis' induced by the CSF of progressive patients in cultured neurons and suggest a critical temporal window of intervention for the rescue of the metabolic impairment of neuronal bioenergetics underlying neurodegeneration in multiple sclerosis patients. [ABSTRACT FROM AUTHOR]

Background. Identification of fungi causing invasive fungal disease (IFD) is critical for guiding antifungal therapy. We describe the performance and clinical impact of a targeted panfungal polymerase chain reaction (PCR) amplicon sequencing assay for culture-independent diagnosis of IFD. Methods. Between January 2009 and September 2016, 233 specimens, consisting of fresh and formalin-fixed, paraffin-embedded (FFPE) tissues and sterile body fluids with known diagnosis of IFD based on reference method results (n = 117), and specimens with negative fungal culture, but with microscopic and ancillary findings indicative of IFD (n = 116), were included. PCR amplicons from the internal transcribed spacer 2 and the D2 region of 28S ribosomal RNA gene were sequenced and fungi identified. Results. Sensitivity and specificity of fungal sequencing in specimens with known diagnosis were 96.6% (95% confidence interval [CI], 87.4%-99.4%; 58/60) and 98.2% (95% CI, 89.4%-99.9%; 56/57). In patients with suspected IFD, the diagnostic yield of fungal sequencing was 62.9% (73/116) overall and 71.3% (57/80) in patients classified with proven IFD based on the European Organization for Research and Treatment of Cancer/Invasive Fungal Infections Cooperative Group and Mycoses Study Group (EORTC/MSG) criteria. Samples obtained by open biopsy had a significantly higher diagnostic yield (71.5% [40/56]) compared with core-needle biopsy (50% [17/34] P = .04) and fine needle aspiration (0% [0/2]; P = .009). Additionally, D2 sequencing diagnosed 5 cases of invasive protozoal infections due to Toxoplasma gondii (n = 3), Trypanosoma cruzi, and Leishmania species. Sequencing results altered patient management in the majority of suspected cases. Conclusions. The targeted fungal sequencing assay allowed accurate identification of fungi causing IFD and additionally provided partial-protozoal coverage. The diagnostic yield was dependent on the amount of tissue available for testing. [ABSTRACT FROM AUTHOR]

Purpose Ibrutinib is a Bruton's tyrosine kinase inhibitor used to treat multiple hematologic malignancies and graft-versus-host disease. Though less myelosuppressive than cytotoxic chemotherapy, increased infections, including invasive fungal infections (IFIs), have been reported with ibrutinib use. This study aimed to determine the characteristics and risk factors for infection associated with ibrutinib at our institution. Methods Patients who received ibrutinib between June 2014 and August 2019 were included. Primary endpoints were the incidence of any infection and the incidence of serious infection (defined as hospitalization, parenteral antimicrobial therapy, or pneumonia regardless of hospitalization). Infection risk factors were assessed using logistic regression. Results One hundred thirty-two patients were identified (78% male; median age, 71 years). The most common indications for ibrutinib were chronic lymphocytic leukemia (67%) and mantle cell lymphoma (12%). Infection and serious infection occurred in 94 (71%) and 47 (36%) patients, respectively; when pneumonia was excluded as a criterion for serious infection, the serious infection rate was 27%. The median time from ibrutinib initiation to first infection was 125 days. Prior allogeneic hematopoietic stem cell transplantation (allo-HSCT) (odds ratio [OR], 4.60; 95% CI, 1.22-17.4) and corticosteroid use (OR, 5.55; 95% CI, 1.52-20.3) were significant risk factors for serious infection. IFIs were diagnosed in 7 patients (5%): 5 had Pneumocystis jirovecii pneumonia and 2 were infected with invasive molds. Conclusion Serious infection and IFI rates are high but similar to those previously described. Risk factors for serious infection included allo-HSCT and corticosteroid use. Targeted antimicrobial prophylaxis should be evaluated in prospective studies in patients on ibrutinib to reduce serious infections and IFI. [ABSTRACT FROM AUTHOR]

A letter to the editor is presented in response to the article "Management of adults with hospital-acquired and ventilator- associated pneumonia: 2016 clinical practice guidelines by the Infectious Diseases Society of America and the American Thoracic Society" by A.C. Kalil in a previous issue.

Background The cost of conventional serological testing for toxoplasmosis discourages universal adoption of prenatal monthly screening programs to prevent congenital toxoplasmosis. Point-of-care (POC) technology may constitute a cost-effective approach. Methods We evaluated the diagnostic accuracy of 3 Toxoplasma POC tests against gold-standard testing performed at Palo Alto Medical Foundation Toxoplasma Serology Laboratory (PAMF-TSL). The POC tests included the following: Toxo IgG/IgM Rapid Test (Biopanda) and the OnSite Toxo IgG/IgM Combo-Rapid- test that detect IgG and IgM separately, and the Toxoplasma ICT-IgG-IgM- bk (LDBIO) that detects either or both immunoglobulin IgG/IgM in combination. Samples were selected from PAMF-TSL biobank (n = 210) and Centers for Disease Control and Prevention Toxoplasma 1998 Human Serum Panel (n = 100). Based on PAMF-TSL testing, Toxoplasma -infection status was classified in 4 categories: acute infections (n = 85), chronic infections (n = 85), false-positive Toxoplasma IgM (n = 60), and seronegative (n = 80). The POC testing was performed in duplicate following manufacturer's instructions by investigators blinded to PAMF-TSL results. Sensitivity and specificity were calculated. Results A total of 1860 POC tests were performed. For detection of Toxoplasma IgG, sensitivity was 100% (170 of 170; 95% confidence interval [CI], 97.8%–100%) for all 3 POC kits; specificity was also comparable at 96.3% (77 of 80; 95% CI, 89.5%–98.9%), 97.5% (78 of 80; 95% CI, 91.3%–99.6%), and 98.8% (79 of 80; 95% CI, 93.2%–99.9%). However, sensitivity for detection of Toxoplasma IgM varied significantly across POC tests: Biopanda, 62.2% (51 of 82; 95% CI, 51.4%–71.9%); OnSite, 28% (23 of 82; 95% CI, 19.5%–38.6%); and LDBIO combined IgG/IgM, 100% (82 of 82; 95% CI, 95.5%–100%). Diagnostic accuracy was significantly higher for the LDBIO POC kit. The POC kits did not exhibit cross-reactivity for false-positive Toxoplasma -IgM sera. Conclusions The 3 evaluated POC kits revealed optimal sensitivity for Toxoplasma -IgG antibodies. The LDBIO -POC test exhibited 100% sensitivity for the combined detection of IgG/IgM in acute and chronic Toxoplasma infection. Biopanda and Onsite POC tests exhibited poor sensitivity for Toxoplasma -IgM detection. [ABSTRACT FROM AUTHOR]

Pentaerythritol tetranitrate (PETN) is a nitrate ester explosive that may be persistent with scarce reports on its environmental fate and impacts. Our main objective was to isolate and characterize bacteria that transform PETN under aerobic and anaerobic conditions. Biotransformation of PETN (100 mg L−1) was evaluated using mineral medium with (M + C) and without (M − C) additional carbon sources under aerobic conditions and with additional carbon sources under anaerobic conditions. Here, we report on the isolation of 12 PETN-transforming cultures (4 pure and 8 co-cultures) from environmental samples collected at an explosive manufacturing plant. The highest transformation of PETN was observed for cultures in M + C under aerobic conditions, reaching up to 91% ± 2% in 2 d. Under this condition, PETN biotransformation was observed in conjunction with the release of nitrites and bacterial growth. No substantial transformation of PETN (<45%) was observed during 21 d in M − C under aerobic conditions. Under anaerobic conditions, five cultures could transform PETN (up to 52% ± 13%) as the sole nitrogen source, concurrent with the formation of two unidentified metabolites. PETN-transforming cultures belonged to Alphaproteobacteria, Betaproteobacteria, Gammaproteobacteria, and Actinobacteria. In conclusion, we isolated 12 PETN-transforming cultures belonging to diverse taxa, suggesting that PETN transformation is phylogenetically widespread. [ABSTRACT FROM AUTHOR]

Background Antimicrobial resistance has worsened in Latin America. There is an urgent need to understand the development of antimicrobial stewardship programs (ASPs) and the barriers to implementing effective ASPs in light of limited national action plans or policies to promote ASPs in the region. Methods We performed a descriptive mixed-methods study of ASPs in 5 Latin American countries in March-July 2022. An electronic questionnaire with an associated scoring system (hospital ASP self-assessment) was used, and ASP development was classified based on the scores (inadequate, 0–25; basic, 26–50; intermediate, 51–75; or advanced, 76–100). Interviews among healthcare workers (HCWs) involved in antimicrobial stewardship (AS) inquired about behavioral and organizational factors that influence AS activities. Interview data were coded into themes. Results from the ASP self-assessment and interviews were integrated to create an explanatory framework. Results Twenty hospitals completed the self-assessment, and 46 AS stakeholders from these hospitals were interviewed. ASP development was inadequate/basic in 35% of hospitals, intermediate in 50%, and advanced in 15%. For-profit hospitals had higher scores than not-for-profit hospitals. Interview data validated the self-assessment findings and provided further insight into ASP implementation challenges, which included limited formal hospital leadership support, inadequate staffing and tools to perform AS work more efficiently, limited awareness of AS principles by HCWs, and limited training opportunities. Conclusions We identified several barriers to ASP development in Latin America, suggesting the need to create accurate business cases for ASPs to obtain the necessary funding for their effective implementation and sustainability. [ABSTRACT FROM AUTHOR]

Background Rising antimicrobial resistance rates may impact the efficacy of empirical antibiotic treatment for febrile neutropenia in high-risk cancer patients. Lacking contemporary data about the epidemiology, antibiotic resistance patterns, and clinical outcomes from bloodstream infections (BSIs) in US cancer patients, it is unclear if current guidelines remain relevant. Methods In a cross-sectional study, 14 US cancer centers prospectively identified BSIs in high-risk febrile neutropenic (FN) patients, including those receiving chemotherapy for hematologic malignancies or hematopoietic stem cell transplantation. Results Among 389 organisms causing BSI in 343 patients, there was an equal distribution of gram-negative (GN) and gram-positive (GP) bacteria, with variability across centers. Cefepime and piperacillin-tazobactam were the most commonly prescribed empirical antibiotics for FN, at 62% and 23%, respectively; a GP-directed agent was empirically included in nearly half of all FN episodes within the first 24 hours. Susceptibility to fluoroquinolones, cefepime, piperacillin-tazobactam, and carbapenems was 49%, 84%, 88%, and 96%, respectively, among GN isolates. Critical illness (CrI), defined as a new requirement for mechanical ventilation, vasopressor, or death within 30 days, occurred in 15% and did not correlate with fluoroquinolone prophylaxis, organism type, initial antibiotics, or adequacy of coverage. Only severity of illness at presentation, signified by a Pitt bacteremia score ≥2, predicted for critical illness within 30 days. Mortality was 4% by day 7 and 10% overall. Conclusions In accordance with US guidelines, cefepime or piperacillin-tazobactam remain effective agents or empirical treatment for high-risk cancer patients with FN who are stable at presentation, maintaining high GN pathogen susceptibility and yielding excellent outcomes. [ABSTRACT FROM AUTHOR]

Background Standard testing fails to identify a pathogen in most patients with febrile neutropenia (FN). We evaluated the ability of the Karius microbial cell-free DNA sequencing test (KT) to identify infectious etiologies of FN and its impact on antimicrobial management. Methods This prospective study (ClinicalTrials.gov; NCT02912117) enrolled and analyzed 55 patients with FN. Up to 5 blood samples were collected per subject within 24 hours of fever onset (T1) and every 2 to 3 days. KT results were compared with blood culture (BC) and standard microbiological testing (SMT) results. Results Positive agreement was defined as KT identification of ≥1 isolate also detected by BC. At T1, positive and negative agreement were 90% (9/10) and 31% (14/45), respectively; 61% of KT detections were polymicrobial. Clinical adjudication by 3 independent infectious diseases specialists categorized Karius results as: unlikely to cause FN (N = 0); definite (N = 12): KT identified ≥1 organism also found by SMT within 7 days; probable (N = 19): KT result was compatible with a clinical diagnosis; possible (N = 10): KT result was consistent with infection but not considered a common cause of FN. Definite, probable, and possible cases were deemed true positives. Following adjudication, KT sensitivity and specificity were 85% (41/48) and 100% (14/14), respectively. Calculated time to diagnosis was generally shorter with KT (87%). Adjudicators determined real-time KT results could have allowed early optimization of antimicrobials in 47% of patients, by addition of antibacterials (20%) (mostly against anaerobes [12.7%]), antivirals (14.5%), and/or antifungals (3.6%); and antimicrobial narrowing in 27.3% of cases. Clinical Trials Registration NCT02912117 Conclusion KT shows promise in the diagnosis and treatment optimization of FN. [ABSTRACT FROM AUTHOR]

Objective: to assess the role of oropharyngeal dysphagia (OD) as a risk factor for malnutrition and/or lower respiratory tract infection (LRTI) in the independently-living population of 70 years and over.Design: a population-based cohort study.Subjects and setting: persons 70 years and over in the community (non-institutionalised) were randomly selected from primary care databases.Measurements: the volume-viscosity swallow test (V-VST) was administered by trained physicians at baseline to identify subjects with clinical signs of OD and impaired safety or efficacy of swallow. At the one year follow-up visit, hand grip, functional capacity (Barthel score), nutritional status (mini nutritional assessment, MNA) and LRTI (clinical notes) were assessed.Results: two hundred and fifty-four subjects were recruited (46.5% female; mean age, 78 years) and 90% of them (227) were re-evaluated one year later. Annual incidence of ‘malnutrition or at risk of malnutrition’ (MNA <23.5) was 18.6% in those with basal signs of OD and 12.3% in those without basal signs of OD (P = 0.296). However, prevalent cases of ‘malnutrition or at risk of malnutrition’ at follow up were associated with basal OD (OR = 2.72; P = 0.010), as well as with basal signs of impaired efficacy of swallow (OR = 2.73; P = 0.015). Otherwise, LRTI's annual incidence was higher in subjects with basal signs of impaired safety of swallow in comparison with subjects without such signs (40.0 versus 21.8%; P = 0.030; OR = 2.39).Conclusions: OD is a risk factor for malnutrition and LRTI in independently living older subjects. These results suggest that older persons should be routinely screened and treated for OD to avoid nutritional and respiratory complications. [ABSTRACT FROM AUTHOR]

Background During 2017, in response to a physician's report, the Wisconsin Department of Health Services, Division of Public Health, began investigating an outbreak of febrile illness among attendees of a retreat where never frozen, intentionally undercooked, locally harvested venison was served. Preliminary testing tentatively identified the illness as toxoplasmosis. Methods Confirmatory human serology panels and testing of the venison to confirm and categorize the presence and type of Toxoplasma gondii were completed by French and American national reference laboratories. All 12 retreat attendees were interviewed; medical records were reviewed. Results All attendees were male; median age was 51 years (range: 22–75). After a median incubation period of 7 days, 9 (82%) of 11 exposed persons experienced illness lasting a median of 12 days. All 9 sought outpatient healthcare for symptoms including fever, chills, sweats, and headache (100%) and ocular disturbances (33%). Testing confirmed the illness as toxoplasmosis and venison as the infection source. Multiple laboratory results were atypical for toxoplasmosis, including transaminitis (86%), lymphocytopenia (88%), thrombocytopenia (38%), and leukopenia (63%). One exposed but asymptomatic person was seronegative; the other had immunity from prior infection. The T. gondii strain was identified as closely related to an atypical genotype (haplogroup 12, polymerase chain reaction restriction fragment length polymorphism genotype 5) common in North American wildlife but with previously uncharacterized human clinical manifestations. Conclusions The T. gondii strain contaminating the venison might explain the unusual clinical presentations. In North America, clinicians and venison consumers should be aware of risk for severe or unusual presentations of acute toxoplasmosis after consuming undercooked game meat. [ABSTRACT FROM AUTHOR]

Background Metagenomic next-generation sequencing (mNGS) of plasma cell-free DNA has emerged as an attractive diagnostic modality allowing broad-range pathogen detection, noninvasive sampling, and earlier diagnosis. However, little is known about its real-world clinical impact as used in routine practice. Methods We performed a retrospective cohort study of all patients for whom plasma mNGS (Karius test) was performed for all indications at 5 United States institutions over 1.5 years. Comprehensive records review was performed, and standardized assessment of clinical impact of the mNGS based on the treating team's interpretation of Karius results and patient management was established. Results A total of 82 Karius tests were evaluated from 39 (47.6%) adults and 43 (52.4%) children and a total of 53 (64.6%) immunocompromised patients. Karius positivity rate was 50 of 82 (61.0%), with 25 (50.0%) showing 2 or more organisms (range, 2–8). The Karius test results led to positive impact in 6 (7.3%), negative impact in 3 (3.7%), and no impact in 71 (86.6%), and was indeterminate in 2 (2.4%). Cases with positive Karius result and clinical impact involved bacteria and/or fungi but not DNA viruses or parasites. In 10 patients who underwent 16 additional repeated tests, only 1 was associated with clinical impact. Conclusions The real-world impact of the Karius test as currently used in routine clinical practice is limited. Further studies are needed to identify high-yield patient populations, define the complementary role of mNGS to conventional microbiological methods, and discern how best to integrate mNGS into current testing algorithms. [ABSTRACT FROM AUTHOR]

A correction for the article "Toxoplasmosis Outbreak Associated With Toxoplasma gondii-Contaminated Venison—High Attack Rate, Unusual Clinical Presentation, and Atypical Genotype" is presented, which is published in the previous issue of the periodical.

Background In this prospective nation-wide survey of bloodstream isolates associated with first episode of FN in high-risk cancer patients from 14 US cancer centers (December 2016 and June 2018), viridans group Streptococci (VGS) were the most common Gram-positive isolate. We sought to clinically and microbiologically characterize VGS bloodstream infections (BSI). Methods Among 343 patients,we compared 90 with VGS vs 253 with non-VGS BSI. Minimum inhibitory concentrations for blood culture isolates were determined by broth dilution for selected agents at our reference microbiology laboratory (UNMC). Clinical data were electronically captured in RedCap, including local site isolate identification and confirmatory reference lab identification via MALDI. Categorical and continuous variables were assessed via chi-square and Mann–Whitney U tests, respectively. Results Ninety-two VGS isolates were identified among 90 FN patients, representing 27% of all BSI isolates. S. mitis or oralis comprised 64 (70%) of VGS. There were no differences between age, sex, and primary diagnosis (50% with AML) among the 2 groups; 1/3 were HSCT recipients. Fluoroquinolone prophylaxis was used in 64 (71%) vs. 139 (55%), P < 0.01, in VGS vs non-VGS groups. Critical illness composite (new need for pressor(s), mechanical ventilation or death within 30 days) was 6 (7%) vs. 44 (17%), P = 0.01, in the VGS vs non-VGS groups. Figure 1 displays an overview of antibiotic susceptibilities for 79 testable isolates. VGS susceptibilities to levofloxacin, penicillin, and ceftriaxone were 39%, 47%, and 94%, respectively. Conclusion VGS are common pathogens in FN patients. Prior fluoroquinolone prophylaxis use may be a risk factor. VGS BSI was not associated with increased critical illness compared with non-VGS. Finally, assuming ceftriaxone susceptibility confers that of cefepime, >90% of VGS are susceptible to empiric FN cefepime regimens. Disclosures All authors: No reported disclosures. [ABSTRACT FROM AUTHOR]

The article describes the case of a 3-year-old toddler who experienced severe pain due to an embryonal bladder/prostate rhabdomyosarcoma. The patient's complaint was a painful tenesmus secondary to the pelvic floor invasion of the mass. The case also describes ganglion impar phenol injection as an effective therapy strategy in a pediatric patient with refractory cancer pain.