Pulmonary insults exacerbate susceptibility to oral Listeria monocytogenes infection through the production of IL-10 by NK cells.

Most individuals who consume foods contaminated with the bacterial pathogen Listeria monocytogenes (Lm) develop mild symptoms, while others are susceptible to life-threatening systemic infections (listeriosis). Although it is known that the risk of severe disease is increased in certain human populations, including the elderly, it remains unclear why others who consume contaminated food develop listeriosis. Here, we used a murine model to discover that pulmonary coinfections can impair the host's ability to adequately control and eradicate systemic Lm that cross from the intestines to the bloodstream.

Sorting nexin 5 mediates virus-induced autophagy and immunity.

Autophagy, a process of degradation that occurs via the lysosomal pathway, has an essential role in multiple aspects of immunity, including immune system development, regulation of innate and adaptive immune and inflammatory responses, selective degradation of intracellular microorganisms, and host protection against infectious diseases. Autophagy is known to be induced by stimuli such as nutrient deprivation and suppression of mTOR, but little is known about how autophagosomal biogenesis is initiated in mammalian cells in response to viral infection. Here, using genome-wide short interfering RNA screens, we find that the endosomal protein sorting nexin 5 (SNX5) is essential for virus-induced, but not for basal, stress- or endosome-induced, autophagy.

IL-10-producing NK cells exacerbate sublethal Streptococcus pneumoniae infection in the lung.

Lung inflammation is tightly controlled to balance microbial clearance with the tissue damage that accompanies this response. Bacterial pathogens including Streptococcus pneumoniae (S. pneumoniae) modulate immune regulation by promoting secretion of the anti-inflammatory cytokine IL-10.

Acute Flaccid Myelitis Among Hospitalized Children in Texas, 2016.

Background: Acute flaccid myelitis is characterized by acute-onset flaccid limb weakness with predominantly gray matter lesions in the spinal cord spanning one or more segments. Rates of full recovery are poor, and there is no standard treatment or definitive cause.

Methods: This is a retrospective review of children diagnosed with acute flaccid myelitis in Texas during 2016.

Inflammation as a Modulator of Host Susceptibility to Pulmonary Influenza, Pneumococcal, and Co-Infections.

Bacterial and viral pathogens are predominant causes of pulmonary infections and complications. Morbidity and mortality from these infections is increased in populations that include the elderly, infants, and individuals with genetic disorders such as Down syndrome. Immune senescence, concurrent infections, and other immune alterations occur in these susceptible populations, but the underlying mechanisms that dictate increased susceptibility to lung infections are not fully defined.

Bacterial Stabilization of a Panel of Picornaviruses.

Several viruses encounter various bacterial species within the host and in the environment. Despite these close encounters, the effects of bacteria on picornaviruses are not completely understood. Previous work determined that poliovirus (PV), an enteric virus, has enhanced virion stability when exposed to bacteria or bacterial surface polysaccharides such as lipopolysaccharide.

Impact of Antibiotic Therapy in the Microbiological Yield of Healthcare-Associated Ventriculitis and Meningitis.

The impact of antibiotic therapy on the diagnosis of healthcare-associated ventriculitis and meningitis (HCAVM) is unknown. Antibiotics were administered before obtaining cerebrospinal fluid (CSF) in 217 out of 326 (66%) patients with HCAVM, and they impacted the sensitivity of the cerebrospinal fluid Gram stain and culture ( ≤ .004).

Strength in numbers: Mechanisms of viral co-infection.

RNA virus populations are diverse due to a variety of factors, including lack of proofreading of the viral RNA-dependent RNA polymerase. These diverse viral populations include defective viruses incapable of productive infection. Recent studies have determined the existence of several modes of viral transmission outside of canonical pathways, including en bloc transmission of multiple viruses into a single host cell via membrane vesicles.

Identification and Characterization of a Poliovirus Capsid Mutant with Enhanced Thermal Stability.

Enteric viruses, including poliovirus, are spread by the fecal-oral route. In order to persist and transmit to a new host, enteric virus particles must remain stable once they are in the environment. Environmental stressors such as heat and disinfectants can inactivate virus particles and prevent viral transmission.

Aseptic meningitis in adults and children: Diagnostic and management challenges.

Background: Aseptic meningitis represents a common diagnostic and management dilemma to clinicians.

Objectives: To compare the clinical epidemiology, diagnostic evaluations, management, and outcomes between adults and children with aseptic meningitis.

Study Design: We conducted a retrospective study from January 2005 through September 2010 at 9 Memorial Hermann Hospitals in Houston, TX.

The clinical significance of neutrophilic pleocytosis in cerebrospinal fluid in patients with viral central nervous system infections.

Background: Viral central nervous system (CNS) infections are typically characterized by a cerebrospinal fluid (CSF) lymphocytic pleocytosis. A CSF neutrophilic pleocytosis presentation has been described, but its prognostic and clinical significance is unknown. The objectives of this study were to (1) compare the clinical and laboratory characteristics of viral CNS infections with a CSF neutrophilic pleocytosis to those with a lymphocytic pleocytosis, and (2) evaluate factors associated with an adverse clinical outcome.

Plaques Formed by Mutagenized Viral Populations Have Elevated Coinfection Frequencies.

The plaque assay is a common technique used to measure virus concentrations and is based upon the principle that each plaque represents a single infectious unit. As such, the number of plaques is expected to correlate linearly with the virus dilution plated, and each plaque should be formed by a single founder virus. Here, we examined whether more than one virus can contribute to plaque formation.

A Novel Emergency Department-based Community Notification Method for Clinical Research Without Consent.

Objective: We used an emergency department (ED)-based method to provide targeted, individualized consultation; community notification; and public disclosure and collect data regarding willingness to participate in prospective resuscitation research requiring waiver of consent.

Methods: We conducted a prospective survey of convenience cohort in an urban ED. We targeted the community of ED patients with pulmonary disease for individualized notification and public disclosure using a 1) large poster, 2) scripted oral presentation describing an emergency intubation clinical trial, and 3) video demonstration.

Risk Classification for Enteroviral Infection in Children With Meningitis and Negative Gram Stain.

Objectives: Enterovirus is the most common cause of aseptic meningitis in children. This study aimed at identifying baseline variables associated with a positive cerebrospinal fluid (CSF) Enterovirus polymerase chain reaction (PCR) to aid clinicians in targeting patients who could be tested and treated as outpatients.

Methods: We performed a retrospective review of children (2 months to 17 years old) admitted to the Children's Memorial Hermann Hospital in Houston, TX, between January 2005 and December 2010 with symptoms of meningitis, CSF white cell count of greater than 5 cells/mm, and a negative CSF Gram stain, who had a CSF Enterovirus PCR.

Identification of Essential Genes in the Salmonella Phage SPN3US Reveals Novel Insights into Giant Phage Head Structure and Assembly.

Unlabelled: Giant tailed bacterial viruses, or phages, such as Pseudomonas aeruginosa phage ϕKZ, have long genomes packaged into large, atypical virions. Many aspects of ϕKZ and related phage biology are poorly understood, mostly due to the fact that the functions of the majority of their proteins are unknown. We hypothesized that the Salmonella enterica phage SPN3US could be a useful model phage to address this gap in knowledge.

Use of Testing for West Nile Virus and Other Arboviruses.

In the United States, the most commonly diagnosed arboviral disease is West Nile virus (WNV) infection. Diagnosis is made by detecting WNV IgG or viral genomic sequences in serum or cerebrospinal fluid. To determine frequency of this testing in WNV-endemic areas, we examined the proportion of tests ordered for patients with meningitis and encephalitis at 9 hospitals in Houston, Texas, USA.

Clinical Characteristics and Predictors of Adverse Outcome in Adult and Pediatric Patients With Healthcare-Associated Ventriculitis and Meningitis.

Background.  Healthcare-associated meningitis or ventriculitis is a serious and life-threatening complication of invasive neurosurgical procedures or penetrating head trauma. Methods.

Enhancing pathogen identification in patients with meningitis and a negative Gram stain using the BioFire FilmArray(®) Meningitis/Encephalitis panel.

Background: Meningitis with a negative cerebrospinal (CSF) Gram stain represents a diagnostic and therapeutic challenge. The purpose of our study was to evaluate the performance of the BioFire FilmArray(®) Meningitis/Encephalitis (FA ME) panel in patients presenting with community-acquired meningitis with a negative Gram stain.

Methods: CSF from 48 patients with community-acquired meningitis with a negative Gram stain admitted to four hospitals in Houston, TX underwent additional testing by the FA ME.

Herpes simplex and varicella zoster CNS infections: clinical presentations, treatments and outcomes.

Objectives: To describe the clinical manifestations, cerebrospinal fluid (CSF) characteristics, imaging studies and prognostic factors of adverse clinical outcomes (ACO) among adults with herpes simplex virus (HSV) or varicella zoster virus (VZV) CNS infections.

Methods: Retrospective review of adult patients with positive HSV or VZV polymerase chain reaction on CSF from an observational study of meningitis or encephalitis in Houston, TX (2004-2014), and New Orleans, LA (1999-2008).

Results: Ninety-eight adults patients were identified; 25 had encephalitis [20 (20.

Unrecognized hypoxia and respiratory depression in emergency department patients sedated for psychomotor agitation: pilot study.

Introduction: The incidence of respiratory depression in patients who are chemically sedated in the emergency department (ED) is not well understood. As the drugs used for chemical restraint are respiratory depressants, improving respiratory monitoring practice in the ED may be warranted. The objective of this study is to describe the incidence of respiratory depression in patients chemically sedated for violent behavior and psychomotor agitation in the ED.

Detection of NH1N1 influenza virus in nonrespiratory sites among children.

Among 20 children admitted with laboratory-confirmed influenza, viral RNA was detected in respiratory secretion, stool and blood in 19, 5 and 1 children, respectively. Gastrointestinal symptoms were common but were not associated with viral RNA in stool. nH1N1 viremia was detected, for the first time, in an immunocompetent child.

Quantitative insulin and C-peptide levels among ED patients with sulfonylurea-induced hypoglycemia-a prospective case series.

Objective: The objective of this study was to measure the serum insulin and C-peptide concentrations among diabetic patients known to be taking sulfonylurea agents who presented to the emergency department with hypoglycemia thought to be due to therapeutic usage as opposed to overdose. A recently published systematic review of 22 articles involving 76 patients with sulfonylurea-induced hypoglycemia (glucose <49 mg/dL) resulting from accidental ingestion or intentional overdose found that patients had an average serum insulin concentration of 3.9 μIU/mL or higher and an average serum C-peptide concentration of 1.