Intrapartum antibiotic prophylaxis selects for mutators in group B streptococci among persistently colonized patients.

Through vaginal colonization, GBS causes severe pregnancy outcomes including neonatal sepsis and meningitis. Although intrapartum antibiotic prophylaxis (IAP) has reduced early-onset disease rates, persistent GBS colonization has been observed in patients following prophylaxis. To determine whether IAP selects for genomic signatures that enhance GBS survival and persistence in the vaginal tract, whole-genome sequencing was performed on 97 isolates from 58 patients before (prenatal) and after (postpartum) IAP/childbirth. Core-gene mutation analysis identified 7,025 mutations between the paired isolates. Three postpartum isolates accounted for 98% of mutations and were classified as "mutators" because of point mutations within DNA repair systems. In vitro assays revealed stronger biofilms in two mutators. These findings suggest that antibiotics select for mutations that promote survival in vivo, which increases the likelihood of transmission to neonates. They also demonstrate how mutators can provide a reservoir of beneficial mutations that enhance fitness and genetic diversity in the GBS population.

Association of cerebrospinal fluid parameters with treatment and complications among children with cerebrospinal fluid shunt infections: a multicenter study.

OBJECTIVE: Cerebrospinal fluid (CSF) white blood cell (WBC) count, neutrophil percentage, protein concentration, and glucose level are typically measured at diagnosis and serially during the treatment of CSF shunt infections. The objective of this retrospective cohort study was to describe the longitudinal profile of CSF parameters in children with CSF shunt infections and assess their association with treatment and outcome. METHODS: Participants were children treated at 11 tertiary pediatric hospitals in Canada and the United States for CSF shunt infection, from July 1, 2013, through June 30, 2019, with hardware removal, external ventricular drain placement, intravenous antibiotics, and subsequent permanent shunt reinsertion. The relationship between CSF parameters and a complicated course (a composite outcome representing children with at least one of the following: contiguous soft-tissue infection, worsening hydrocephalus, CSF leak, intracranial bleed, brain abscess, venous thrombosis, reinfection after insertion of the new shunt, other complication, ICU admission, or death) was analyzed. RESULTS: A total of 109 children (median age 2.8 years, 44% female) were included in this study. CSF pleocytosis, elevated protein, and hypoglycorrhachia had sensitivities of 69%, 47%, and 38% for the diagnosis of culture-confirmed CSF shunt infection, respectively. The longitudinal profile of the neutrophil percentage followed a monotonic trend, decreasing by 1.5% (95% CI 1.0%-2.0%, p < 0.0001) per day over the course of treatment. The initial WBC count differed significantly between pathogens (p = 0.011), but the proportion of neutrophils, protein concentration, and glucose level did not, and was lowest with Cutibacterium acnes. The duration of antibiotic treatment and the time to shunt reinsertion were longer in patients with a higher initial neutrophil percentage. Fifty-eight patients (53%) had one or more complications during their admission. A neutrophil percentage > 44% (Youden index) in the initial CSF sample was associated with a 1.8-fold (95% CI 1.2- to 2.8-fold) higher relative risk of a complicated course. In a random-intercept, random-slope linear mixed-effects model, the longitudinal neutrophil trajectory differed significantly between patients with and without complications (p = 0.030). CONCLUSIONS: A higher proportion of neutrophils in the CSF at diagnosis was associated with a complicated clinical course. Other CSF parameters were associated with treatment and outcome; however, wide variability in values may limit their clinical utility.

The relationship between nutrition, gut dysbiosis, and pediatric sickle cell pain outcomes: A pilot study.

BACKGROUND: Nutritional deficiencies are prevalent in sickle cell disease (SCD) and may be associated with worse pain outcomes. Gut dysbiosis has been reported in patients with SCD and may contribute to both nutritional deficiencies and pain. OBJECTIVES: We tested the association of nutrition, fat-soluble vitamin (FSV) deficiency, and gut microbiome composition on clinical outcomes in SCD. Second, we measured the association between diet and exocrine pancreatic function on FSV levels. METHODS: Using case control design, we enrolled children with SCD (n = 24) and matched healthy controls (HC; n = 17, age, sex, race/ethnicity). Descriptive statistics summarized demographic and clinical data. Wilcoxson-rank tests compared FSV levels between cohorts. Regression modeling tested the association between FSV levels and SCD status. Welch's t-test with Satterthwaite adjustment evaluated associations between microbiota profiles, SCD status, and pain outcomes. RESULTS: Vitamin A and D levels were significantly decreased in participants with HbSS as compared to HC (vitamin A, p = < .0001, vitamin D, p = .014) independent of nutritional status. FSV correlated with dietary intake in SCD and HC cohorts. Gut microbial diversity was reduced in hemoglobin SS (HbSS) compared to hemoglobin SC (HbSC) and HC, p = .037 and .059, respectively. The phyla Erysipelotrichaceae and Betaproteobacteria were higher in SCD children reporting the highest quality-of-life (QoL) scores (p = .008 and .049, respectively), while Clostridia were higher in those with lower QoL scores (p = .03). CONCLUSION: FSV deficiencies and gut dysbiosis are prevalent in children with SCA. Gut microbial composition is significantly different in children with SCD with low QoL scores.

Asset-based Community "Response": A Model Promoting Effective Student- Community Engagement in Disaster Scenarios.

BACKGROUND: In response to the coronavirus disease 2019 (COVID-19) pandemic, medical students organized grass-roots volunteer initiatives to address community-level needs. These required community partnerships and extra-institutional resources to effectively operate. Due to curricular constraints, these efforts often lacked familiarity and working knowledge of existing university infrastructure on how to engage with established community partnerships and resources. OBJECTIVES: The authors call for institutions to capitalize upon the response experience gained by medical students during the pandemic. This includes 1) formally integrating the infrastructure and community relationships established by student COVID-19 volunteer initiatives into existing university community-engagement systems, and 2) incorporating asset-based community development (ABCD) into medical student curricula as a framework for community engagement and disaster response. METHODS: A case study from the University of Nebraska Medical Center presents student COVID-19 response initiatives, their outcomes, and how their approach emulated the ABCD model. The ABCD model asserts that communities should use asset mapping to identify the skills and resources of community members, rather than using deficiency-oriented approaches. Further, the case study demonstrates how the use of an established ABCD model could have contributed to a more effective and efficient COVID-19 student response. CONCLUSIONS: Experiences at University of Nebraska Medical Center support the value of using a modified ABCD model to facilitate community relationships related to rapid health response. Formal integration of the ABCD model within a university's centralized office of community engagement will increase access and foster town-gown reciprocal relationships, empowering students, academic health centers, and surrounding communities in times of crisis and calm.

Duration of Antibiotic Therapy and Timing of Shunt Reimplantation in Pediatric CSF Shunt Infections: A Retrospective Multicenter Case Series.

In this retrospective multicenter series of 154 children with cerebrospinal fluid shunt infections, the median (interquartile range) duration of antibiotic therapy was 18 (14-26) days. The time to shunt replacement was 14 (10-19) days. Management appeared to potentially differ according to the targeted pathogen and site.

Cerebrospinal Fluid Shunt Infections: A Multicenter Pediatric Study.

BACKGROUND: Infections complicate 5%-10% of cerebrospinal fluid (CSF) shunts. We aimed to describe the characteristics and contemporary pathogens of shunt infections in children in Canada and the United States. METHODS: Descriptive case series at tertiary care hospitals in Canada (N = 8) and the United States (N = 3) of children up to 18 years of age with CSF shunt infections from July 1, 2013, through June 30, 2019. RESULTS: There were 154 children (43% female, median age 2.7 years, 50% premature) with ≥1 CSF shunt infections. Median time between shunt placement and infection was 54 days (interquartile range, 24 days-2.3 years). Common pathogens were coagulase-negative staphylococci (N = 42; 28%), methicillin-susceptible Staphylococcus aureus (N = 24; 16%), methicillin-resistant S. aureus (N = 9; 5.9%), Pseudomonas aeruginosa (N = 9; 5.9%) and other Gram-negative bacilli (N = 14; 9.0%). Significant differences between pathogens were observed, including timing of infection (P = 0.023) and CSF leukocyte count (P = 0.0019); however, differences were not sufficient to reliably predict the causative organism based on the timing of infection or discriminate P. aeruginosa from other pathogens based on clinical features. Empiric antibiotic regimens, which included vancomycin (71%), cefotaxime or ceftriaxone (29%) and antipseudomonal beta-lactams (33%), were discordant with the pathogen isolated in five cases. There was variability between sites in the distribution of pathogens and choice of empiric antibiotics. Nine children died; 4 (44%) deaths were attributed to shunt infection. CONCLUSIONS: Staphylococci remain the most common cause of CSF shunt infections, although antibiotic resistant Gram-negative bacilli occur and cannot be reliably predicted based on clinical characteristics.

Expansion of simulation and extended reality for undergraduate health professions education: A call to action.

In the spring of 2020, the COVID-19 pandemic limited access for many health professions students to clinical settings amid concerns about availability of appropriate personal protective equipment as well as the desire to limit exposure in these high-risk settings. Furthermore, the pandemic led to a need to cancel clinics and inpatient rotations, with a major impact on training for health professions and interprofessional health delivery, the long-term effects of which are currently unknown. While problematic, this also presents an opportunity to reflect on challenges facing the traditional clinical training paradigm in a rapidly changing and complex health care system and develop sustainable, high-quality competency-based educational models that incorporate rapidly progressing technologies. We call for pilot studies to explore specific simulation-based inpatient and outpatient clinical rotations for professional and interprofessional training.

Perspectives on the Management of Children in a Biocontainment Unit: Report of the NETEC Pediatric Workgroup.

During the outbreak of Ebola virus disease that struck West Africa during 2014-2016, a small handful of expatriate patients were evacuated to specialized high-level containment care units, or biocontainment units, in the United States and Western Europe. Given the lower mortality rate (18% versus 40% for those treated in Africa) among these patients, it is likely that high-level containment care will be used in the future with increasing frequency. It is also likely that children infected with Ebola and other highly hazardous communicable diseases will someday require such care. The National Ebola Training and Education Center convened a pediatric workgroup to consider the unique and problematic issues posed by these potential child patients. We report here the results of those discussions.

Infectious Diseases Associated With Organized Sports and Outbreak Control.

Participation in organized sports has a variety of health benefits but also has the potential to expose the athlete to a variety of infectious diseases, some of which may produce outbreaks. Major risk factors for infection include skin-to-skin contact with athletes who have active skin infections, environmental exposures and physical trauma, and sharing of equipment and contact with contaminated fomites. Close contact that is intrinsic to team sports and psychosocial factors associated with adolescence are additional risks. Minimizing risk requires leadership by the organized sports community (including the athlete's primary care provider) and depends on outlining key hygiene behaviors, recognition, diagnosis, and treatment of common sports-related infections, and the implementation of preventive interventions.

Intrinsic Maturational Neonatal Immune Deficiencies and Susceptibility to Group B Streptococcus Infection.

Although a normal member of the gastrointestinal and vaginal microbiota, group B Streptococcus (GBS) can also occasionally be the cause of highly invasive neonatal disease and is an emerging pathogen in both elderly and immunocompromised adults. Neonatal GBS infections are typically transmitted from mother to baby either in utero or during passage through the birth canal and can lead to pneumonia, sepsis, and meningitis within the first few months of life. Compared to the adult immune system, the neonatal immune system has a number of deficiencies, making neonates more susceptible to infection. Recognition of GBS by the host immune system triggers an inflammatory response to clear the pathogen. However, GBS has developed several mechanisms to evade the host immune response. A comprehensive understanding of this interplay between GBS and the host immune system will aid in the development of new preventative measures and therapeutics.

Early-Onset Invasive Candidiasis in Extremely Low Birth Weight Infants: Perinatal Acquisition Predicts Poor Outcome.

BACKGROUND: Neonatal invasive candidiasis (IC) presenting in the first week of life is less common and less well described than later-onset IC. Risk factors, clinical features, and disease outcomes have not been studied in early-onset disease (EOD, ≤7 days) or compared to late-onset disease (LOD, >7 days). METHODS: All extremely low birth weight (ELBW, <1000 g) cases with IC and controls from a multicenter study of neonatal candidiasis enrolled from 2001 to 2003 were included in this study. Factors associated with occurrence and outcome of EOD in ELBW infants were determined. RESULTS: Forty-five ELBW infants and their 84 matched controls were included. Fourteen (31%) ELBW infants had EOD. Birth weight <750 g, gestation <25 weeks, chorioamnionitis, and vaginal delivery were all strongly associated with EOD. Infection with Candida albicans, disseminated disease, pneumonia, and cardiovascular disease were significantly more common in EOD than in LOD. The EOD case fatality rate (71%) was higher than in LOD (32%) or controls (15%) (P = .0001). The rate of neurodevelopmental impairment and mortality combined was similar in EOD (86%) and LOD (72%), but higher than in controls (32%; P = .007). CONCLUSIONS: ELBW infants with EOD have a very poor prognosis compared to those with LOD. The role of perinatal transmission in EOD is supported by its association with chorioamnionitis, vaginal delivery, and pneumonia. Dissemination and cardiovascular involvement are common, and affected infants often die. Empiric treatment should be considered for ELBW infants delivered vaginally who have pneumonia and whose mothers have chorioamnionitis or an intrauterine foreign body.

Parental Presence During Treatment of Ebola or Other Highly Consequential Infection.

This clinical report offers guidance to health care providers and hospitals on options to consider regarding parental presence at the bedside while caring for a child with suspected or proven Ebola virus disease (Ebola) or other highly consequential infection. Options are presented to help meet the needs of the patient and the family while also posing the least risk to providers and health care organizations. The optimal way to minimize risk is to limit contact between the person under investigation or treatment and family members/caregivers whenever possible while working to meet the emotional support needs of both patient and family. At times, caregiver presence may be deemed to be in the best interest of the patient, and in such situations, a strong effort should be made to limit potential risks of exposure to the caregiver, health care providers, and the community. The decision to allow parental/caregiver presence should be made in consultation with a team including an infectious diseases expert and state and/or local public health authorities and should involve consideration of many factors, depending on the stage of investigation and management, including (1) a careful history, physical examination, and investigations to elucidate the likelihood of the diagnosis of Ebola or other highly consequential infection; (2) ability of the facility to offer appropriate isolation for the person under investigation and family members and to manage Ebola; (3) ability to recognize and exclude people at increased risk of worse outcomes (eg, pregnant women); and (4) ability of parent/caregiver to follow instructions, including appropriate donning and doffing of personal protective equipment.

Infectious Complications With the Use of Biologic Response Modifiers in Infants and Children.

Biologic response modifiers (BRMs) are substances that interact with and modify the host immune system. BRMs that dampen the immune system are used to treat conditions such as juvenile idiopathic arthritis, psoriatic arthritis, or inflammatory bowel disease and often in combination with other immunosuppressive agents, such as methotrexate and corticosteroids. Cytokines that are targeted include tumor necrosis factor α; interleukins (ILs) 6, 12, and 23; and the receptors for IL-1α (IL-1A) and IL-1ß (IL-1B) as well as other molecules. Although the risk varies with the class of BRM, patients receiving immune-dampening BRMs generally are at increased risk of infection or reactivation with mycobacterial infections (Mycobacterium tuberculosis and nontuberculous mycobacteria), some viral (herpes simplex virus, varicella-zoster virus, Epstein-Barr virus, hepatitis B) and fungal (histoplasmosis, coccidioidomycosis) infections, as well as other opportunistic infections. The use of BRMs warrants careful determination of infectious risk on the basis of history (including exposure, residence, and travel and immunization history) and selected baseline screening test results. Routine immunizations should be given at least 2 weeks (inactivated or subunit vaccines) or 4 weeks (live vaccines) before initiation of BRMs whenever feasible, and inactivated influenza vaccine should be given annually. Inactivated and subunit vaccines should be given when needed while taking BRMs, but live vaccines should be avoided unless under special circumstances in consultation with an infectious diseases specialist. If the patient develops a febrile or serious respiratory illness during BRM therapy, consideration should be given to stopping the BRM while actively searching for and treating possible infectious causes.

Association between genotypic diversity and biofilm production in group B Streptococcus.

BACKGROUND: Group B Streptococcus (GBS) is a leading cause of sepsis and meningitis and an important factor in premature and stillbirths. Biofilm production has been suggested to be important for GBS pathogenesis alongside many other elements, including phylogenetic lineage and virulence factors, such as pili and capsule type. A complete understanding of the confluence of these components, however, is lacking. To identify associations between biofilm phenotype, pilus profile and lineage, 293 strains from asymptomatic carriers, invasive disease cases, and bovine mastitis cases, were assessed for biofilm production using an in vitro assay. RESULTS: Multilocus sequence type (ST) profile, pilus island profile, and isolate source were associated with biofilm production. Strains from invasive disease cases and/or belonging to the ST-17 and ST-19 lineages were significantly more likely to form weak biofilms, whereas strains producing strong biofilms were recovered more frequently from individuals with asymptomatic colonization. CONCLUSIONS: These data suggest that biofilm production is a lineage-specific trait in GBS and may promote colonization of strains representing lineages other than STs 17 and 19. The findings herein also demonstrate that biofilms must be considered in the treatment of pregnant women, particularly for women with heavy GBS colonization.

Draft Genome Sequence of an Invasive Streptococcus agalactiae Isolate Lacking Pigmentation.

This report provides the whole-genome sequence of Streptococcus agalactiae isolate GB00037 isolated from a newborn in Calgary, Canada. This serotype V isolate is unique because it lacks pigment production previously shown to be critical for S. agalactiae virulence.

Pilus distribution among lineages of group b streptococcus: an evolutionary and clinical perspective.

BACKGROUND: Group B Streptococcus (GBS) is an opportunistic pathogen in both humans and bovines. Epidemiological and phylogenetic analyses have found strains belonging to certain phylogenetic lineages to be more frequently associated with invasive newborn disease, asymptomatic maternal colonization, and subclinical bovine mastitis. Pilus structures in GBS facilitate colonization and invasion of host tissues and play a role in biofilm formation, though few large-scale studies have estimated the frequency and diversity of the three pilus islands (PIs) across diverse genotypes. Here, we examined the distribution of pilus islands (PI) 1, 2a and 2b among 295 GBS strains representing 73 multilocus sequence types (STs) belonging to eight clonal complexes. PCR-based RFLP was also used to evaluate variation in the genes encoding pilus backbone proteins of PI-2a and PI-2b. RESULTS: All 295 strains harbored one of the PI-2 variants and most human-derived strains contained PI-1. Bovine-derived strains lacked PI-1 and possessed a unique PI-2b backbone protein allele. Neonatal strains more frequently had PI-1 and a PI-2 variant than maternal colonizing strains, and most CC-17 strains had PI-1 and PI-2b with a distinct backbone protein allele. Furthermore, we present evidence for the frequent gain and loss of genes encoding certain pilus types. CONCLUSIONS: These data suggest that pilus combinations impact host specificity and disease presentation and that diversification often involves the loss or acquisition of PIs. Such findings have implications for the development of GBS vaccines that target the three pilus islands.

Early-onset neonatal sepsis.

Early-onset sepsis remains a common and serious problem for neonates, especially preterm infants. Group B streptococcus (GBS) is the most common etiologic agent, while Escherichia coli is the most common cause of mortality. Current efforts toward maternal intrapartum antimicrobial prophylaxis have significantly reduced the rates of GBS disease but have been associated with increased rates of Gram-negative infections, especially among very-low-birth-weight infants. The diagnosis of neonatal sepsis is based on a combination of clinical presentation; the use of nonspecific markers, including C-reactive protein and procalcitonin (where available); blood cultures; and the use of molecular methods, including PCR. Cytokines, including interleukin 6 (IL-6), interleukin 8 (IL-8), gamma interferon (IFN-γ), and tumor necrosis factor alpha (TNF-α), and cell surface antigens, including soluble intercellular adhesion molecule (sICAM) and CD64, are also being increasingly examined for use as nonspecific screening measures for neonatal sepsis. Viruses, in particular enteroviruses, parechoviruses, and herpes simplex virus (HSV), should be considered in the differential diagnosis. Empirical treatment should be based on local patterns of antimicrobial resistance but typically consists of the use of ampicillin and gentamicin, or ampicillin and cefotaxime if meningitis is suspected, until the etiologic agent has been identified. Current research is focused primarily on development of vaccines against GBS.