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De novo protein design has been successful in expanding the natural protein repertoire. However, most de novo proteins lack biological function, presenting a major methodological challenge. In vaccinology, the induction of precise antibody responses remains a cornerstone for next-generation vaccines. Here, we present a protein design algorithm called TopoBuilder, with which we engineered epitope-focused immunogens displaying complex structural motifs. In both mice and nonhuman primates, cocktails of three de novo-designed immunogens induced robust neutralizing responses against the respiratory syncytial virus. Furthermore, the immunogens refocused preexisting antibody responses toward defined neutralization epitopes. Overall, our design approach opens the possibility of targeting specific epitopes for the development of vaccines and therapeutic antibodies and, more generally, will be applicable to the design of de novo proteins displaying complex functional motifs. This work was supported by the swiss initiative for systems biology (SystemsX.ch), the European Research Council (Starting grant - 716058), the Swiss National Science Foundation (310030_163139) and the EPFL’s Catalyze4Life initiative. F.S. was supported by an SNF/Innosuisse BRIDGE Proof-of-Concept grant. J.B. was supported by the EPFL Fellows postdoctoral fellowship. T.K. received funding from the German Center of Infection Research (DZIF) and the Cluster of Excellence RESIST (EXC 2155) of the German Research foundation. J.T.C. was funded by the ERA-Net PrionImmunity project 01GM1503 (Federal Ministry of Education and Research, Germany). V.M. received funding from “AESI-18” (Instituto de Salud Carlos III), grant MPY 375/18. J.PJ. was funded by the Canada Research Chairs program (J.P.J.), T.J. and X.W. were funded by the NIH NIAID (R01 AI137523). The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript. Sí

OBJECTIVES:Although hypothermia has long been considered a sign of serious bacterial infection (SBI) in neonates, there is a lack of medical literature on this topic, and little is known about the prevalence of serious infection in these patients. Our primary objective was to assess the prevalence and type of serious infection in neonates with hypothermia. Our secondary objective was to describe the prevalence and type of significant pathology overall in this cohort.METHODS:We examined neonates (≤28 days old) evaluated in the emergency department and/or admitted to the hospital with hypothermia over a 3-year period. Demographics and relevant clinical data were extracted from the medical record. Fisher’s exact test was used to determine differences in the prevalence of clinical and demographic characteristics in patients with and without a diagnosis of serious infection.RESULTS:Sixty-eight neonates met inclusion criteria, and 63 (93%) were admitted. Of those admitted to the hospital, 5 (7.9%) had a diagnosis of serious infection, including SBI (n = 4) and disseminated herpes simplex virus (n = 1). The types of SBI included urinary tract infection, septicemia, and meningitis. Eighty percent and 60% of neonates with hypothermia and diagnosed with serious infection had a temperature ≤34.4°C and ill appearance, respectively. Significant pathology was found in 9 (14.3%) patients and included both infectious and noninfectious diagnoses.CONCLUSIONS:Neonates presenting with hypothermia have a substantial risk for SBI or other significant pathology. This population merits further investigation; a multicenter prospective study should be conducted to better understand associations between risk factors and outcomes.

Trimethoprim-sulfamethoxazole (Septra) is a widely used antibiotic world-wide.The clinical use has been increasing in the pediatric population[1]. Septra has been associated with a broad array of drug associated reactions including gastrointestinal complaints, cutaneous reactions including Stevens-Johnson syndrome and toxic epidermal necrolysisand cytopenias including immune mediated thrombocytopenia[2]. Adverse reactions occur in 6-8% of patients. In the pediatric patient hospitalized for an adverse drug reaction priorexposure to Septra is found in 75% of patients [3].In the case presented we describe a cutaneous reaction to Septra clinically consistent with a Type2 hypersensitivity reaction with associated pancytopenia. Idiosyncratic reactions such as Type 2 hypersensitivity have rarely been reported with Septra exposure.These adverse drug reactions have infrequently been reported to be fatal [4].With the increasing use of Septra for the management of community acquired methicillin resistant Staphylococcus aureus of skin and soft tissue infections [5] clinicians will need to recognize this clinical complication.

This article focuses on pediatric patients whose difficult medical presentation includes both physical and psychological components. These patients do not have a known psychiatric diagnosis and often have had previous hospitalizations for presumed organic illness. Results of diagnostic testing are generally uninformative, and management is time-intensive, involving multiple health care providers and significant medical resources. Antagonism in the relationship between the physician and parent frequently develops.1 Although diverse in presentation and outcome, conceptualization of these “med-psych” cases into general categories may result in early recognition of these patients, decreased hospital length of stay and expense, improved quality of the physician–parent relationship, and increased treatment effectiveness. We describe 2 different types of cases, outline effective and ineffective interventions, and discuss unresolved difficulties with management. Due to a paucity of relevant research, this article is based primarily on clinical experience. A 15-year-old male was hospitalized after 3 weeks of tachycardia, syncope, tingling in his hands, and subjective fevers. Medical history included an irregular heartbeat. His mother also has mitral valve prolapse and panic attacks. The family initially did not report school or behavioral difficulties. He and his parents indicated significant fear about something “being seriously wrong with him.” After results of initial diagnostic testing were unrevealing, further interviews elicited that the patient had recently been expelled from school due to a fight. He was assigned to an alternative school, which limited his school-related activities and eliminated contact with previous classmates. He also expressed sadness regarding the death of his grandmother ~18 months prior. His affect was generally flat, he cried easily when talking about his grandmother, and he had lost interest in previously satisfying activities. This case is typical of pediatric patients who present with medically unexplained somatic complaints such as fatigue, abdominal pain, musculoskeletal pain, syncope, and/or headache. Nausea and …

The aim of this study was to characterize the practice of routinely obtaining tracheal aspirate cultures in children with tracheostomy tubes and to analyze the appropriateness of using this information to guide antibiotic selection for treatment of subsequent lower respiratory infections.Pediatric otolaryngologists and pulmonologists were surveyed regarding surveillance culture practices. Records of children with tracheostomy tubes from January 1, 2003, through December 31, 2007, were reviewed. Consecutive cultures were compared for similarity of bacteria and antibiotic sensitivity when a clinic culture preceded a culture from when the child was ill and received antibiotics and when a hospital culture preceded a hospital culture from a separate hospitalization.Seventy-nine of 146 pulmonologists and five of 33 otolaryngologists obtained routine surveillance tracheal aspirate cultures (P.001); 97% of pulmonologists used these cultures to guide subsequent empiric therapy. There were 36 of 170 children with one or more eligible pairs of cultures. Nearly all children had a change in flora in their tracheal cultures. Limiting empiric antibiotic choices to those that would cover microbes isolated in the previous culture likely would not have been effective in covering one or more microbes isolated in the second culture in 56% of pairs with the first culture from hospitalization vs 30% with the first culture from an outpatient setting (P = .15).This study demonstrated that there are significant changes in bacteria or antibiotic sensitivity between consecutive tracheal cultures in children with tracheostomy tubes. Use of prior tracheal cultures from these children was of limited value for choosing empiric antibiotic therapy in treating acute lower respiratory exacerbations. Surveillance cultures, thus, are an unnecessary burden and expense of care.

There is currently no approved vaccine against Pseudomonas aeruginosa, the major cause of morbidity and mortality in cystic fibrosis (CF) patients and a major pathogen in ventilated and burn patients. In a previous study, we demonstrated the immunization of mice with OprF(311-341)-OprI-type A- and B-flagellin fusion proteins dramatically enhanced clearance of nonmucoid P. aeruginosa. The goal of the current study was to evaluate the ability of OprF(311-341)-OprI-flagellins to elicit the production of protective IgG in young (4-6 months old) African green monkeys. Intramuscular immunization of African green monkeys with 1, 3, 10, or 30mug of OprF(311-341)-OprI-flagellins generated robust antigen-specific IgG responses. In addition, immunization with OprF(311-341)-OprI-flagellins elicited high-affinity anti-flagellins, OprI, and OprF IgG that individually promoted extensive deposition of complement component C3 on P. aeruginosa and synergized to facilitate maximal C3 deposition. Passive immunization of mice with plasma from OprF(311-341)-OprI-flagellins immunized monkeys significantly reduced lung bacterial burden three days post-challenge compared to mice that received pre-immunization plasma. Based on our results, OprF(311-341)-OprI-A- and B-flagellin fusion proteins are highly effective in mice and nonhuman primates and thus merit additional development as a potential vaccine for use in humans.

BACKGROUND: The incidence of venous thromboembolism (VTE) is increasing among pediatric patients in the United States. Previous studies on obesity as a risk factor have produced mixed results. METHODS: We completed a retrospective chart review of patients aged 2 to 18 years with VTE identified by using International Classification of Diseases, Ninth Revision, codes and confirmed by imaging. Patients were admitted between January 2000 and September 2012. Control subjects were matched on age, gender, and the presence of a central venous catheter. Data were collected on weight, height, and risk factors, including bacteremia, ICU admission, immobilization, use of oral contraceptives, and malignancy. Underweight patients and those without documented height and weight data were excluded. Independent predictors of VTE risk were identified by using univariate and multivariate analyses. RESULTS: We identified 88 patients plus 2 matched control subjects per case. The majority of cases were nonembolic events (77%) of the lower extremity (25%) or head and neck (22%) confirmed by ultrasound (43%) or computed tomography scan (41%). A statistically significant association was found between VTE and increased BMI z score (P = .002). In multivariate analysis, BMI z score (odds ratio [OR]: 3.1; P = .007), bacteremia (OR: 4.9; P = .02), ICU stay (OR: 2.5; P = .02), and use of oral contraceptives (OR: 17.4; P < .001) were significant predictors. CONCLUSIONS: In this single-institution study, the diagnosis of VTE was significantly associated with overweight and obesity. Further study is needed to fully define this association.

Background: Though treatment of severe acute malnutrition cases in both the in-patient care and the outpatient care has been going on since 2011 at the Tamale Teaching Hospital, little is known about the clinical treatment outcomes and factors that may be associated with the recovery rate in the in-patient setting. This study investigated the clinical treatment outcomes and determinant factors likely to be associated with recovery rates at the Hospital. Methods: We performed a retrospective chart review (RCR) of all pediatric patients aged (0-11 years of age) who were diagnosed of severe acute malnutrition between March 2011 and December 2013. Logistic regression modeling was used to determine the risk factors of severe malnutrition. Results: Of the 630 cases that were reviewed, only 19.5 % recovered (having mid-upper-arm-circumference measure 􀀁125 mm, or oedema resolved, or gained 5g/kg/body weight for 2 consecutive days at the time of discharge), 1.7 % defaulted, and 65.2 % were referred to out-patient care units for continued treatment. The observed case fatality rate was 13.5 %. Marasmic cases had more chronic co-morbid conditions at admission compared to kwashiorkor patients (81.7% vs. 69.3%, p=0.01). Conclusions: Case fatality rate in this population was quite high. Case referral to out-patient care unit was appropriately high. Malaria was the most common co-morbid condition diagnosed among the cases reviewed. Younger age, 15% or more increase in weight, and type of malnutrition were the main predictors of recovery from severe acute malnutrition in the in-patient care setting.

Objective.This study investigated the treatment outcomes and determinant factors likely to be associated with recovery rate.Methods.A retrospective chart review (RCR) was performed on 348 patients who were enrolled in the outpatient care (OPC) during the study period.Results.Of the 348 cases, 33.6% recovered (having MUAC≥125 mm), 49.1% defaulted, and 11.5% transferred to other OPC units to continue with treatment. There were 187 (53.7%) males and 161 (46.3%) females with severe malnutrition. The average weight gain rate was 28 g/kg/day. Controlling for other factors, patients who completed the treatment plan had 3.2 times higher probability of recovery from severe acute malnutrition (SAM) as compared to patients who defaulted (adjusted odds ratio (AOR) = 3.2, 95% CI = 1.9, 5.3, andp<0.001). The children aged 24–59 months had 5.8 times higher probability of recovery from SAM as compared to children aged 6–11 months (AOR = 5.8, 95% CI = 2.5, 10.6, andp<0.001).Conclusions.Cure rate was low and the default rate was quite high. Children who were diagnosed as having marasmus on admission stayed longer before recovery than their kwashiorkor counterparts. Younger children were of greater risk of nonrecovery.

Children with somatoform illness present a real diagnostic and management puzzle for the pediatric hospitalist. These children are a source of diagnostic confusion, often leading to unnecessary hospitalization, extensive testing, and frustration on the part of caretakers and providers. The psychiatric underpinnings of their clinical presentation are frequently only discovered through a process of elimination, leading to a diagnosis of exclusion for these children presenting with somatoform disorders. In this issue of Hospital Pediatrics , Bujoreanu and colleagues1 present their experience with this patient population in a large children’s hospital. This work, in association with a previous discussion on this topic in this journal,2 offers a way through this …

Objectives: We investigated the association of nil per os (NPO) status and subsequent nutritional support with patient weight and length of stay (LOS) during admission for bronchiolitis in patients Methods: A retrospective chart review was performed of all patients Results: The study included 149 patients. The mean ± SD patient age was 3.7 ± 3.8 months, with a median age of 2 months. The median length of stay was 4 days (interquartile range: 3–6). Overall, 16% of patients were made NPO, 75% received intravenous fluids, and 9% received enteral tube feedings. The mean weight loss for all patients was 38 (289) g during the hospitalization, which was not statistically significant. No significant association was found between weight loss and LOS, per os/NPO status, or use of intravenous fluids. However, NPO status was associated with a significant increase in LOS. Conclusions: The infants admitted for bronchiolitis did not demonstrate weight loss in this study; however, an association was seen between NPO status and prolonged LOS.

Tuberculosis (TB) is the most important zoonotic bacterial disease in nonhuman primates (NHP). The current diagnostic method, the intradermal palpebral tuberculin test, has serious shortcomings. We characterized antibody responses in NHP againstMycobacterium tuberculosisto identify immunodominant antigens and develop a rapid serodiagnostic test for TB. A total of 422 NHP were evaluated, including 243 rhesus (Macaca mulatta), 46 cynomolgus (Macaca fascicularis), and 133 African green (Cercopithecus aethiops sabaeus) monkeys at five collaborative centers. Of those, 50 monkeys of the three species were experimentally inoculated withM. tuberculosis. Antibody responses were monitored every 2 to 4 weeks for up to 8 months postinfection by MultiAntigen Print ImmunoAssay with a panel of 12 recombinant antigens. All of the infected monkeys produced antibodies at various levels and with different antigen recognition patterns. ESAT-6 and MPB83 were the most frequently recognized proteins during infection. A combination of selected antigens which detected antibodies in all of the infected monkeys was designed to develop the PrimaTB STAT-PAK assay by lateral-flow technology. Serological evaluation demonstrated high diagnostic sensitivity (90%) and specificity (99%). The highest rate of TB detection was achieved when the skin test was combined with the PrimaTB STAT-PAK kit. This novel immunoassay provides a simple, rapid, and accurate test for TB in NHP.