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Christopher W Woods

Publications and source records attributed to Christopher W Woods.

At least 19 recordsLinked to original sources
PubMed2025

Innate immune molecular landscape following controlled human influenza virus infection.

Viral infections can induce prolonged changes in innate immunity. Here, we use blood samples from a human influenza H3N2 challenge study (NCT03883113) to perform comprehensive multi-omics analyses. We detect remodeling of immune programs in circulating innate immune cells that persist after resolution of the infection. We find changes associated with suppressed inflammation, including decreased cytokine and AP-1 gene expression as well as decreased accessibility at AP-1 targets and interleukin-related gene promoter regions. We also find decreased histone deacetylase gene expression, increased MAP kinase gene expression, and increased accessibility at interferon-related gene promoter regions. Genes involved in inflammation and methylation remodeling show modulation of gene-chromatin site regulatory circuit activity. These results reveal a coordinated rewiring of the molecular landscape in innate immune cells induced by mild influenza virus infection.

Humans↗
PubMed2007

Early surgery in patients with infective endocarditis: a propensity score analysis.

BACKGROUND: An accurate assessment of the predictors of long-term mortality in patients with infective endocarditis is not possible using retrospective data because of inherent treatment biases and predictable imbalances in the distribution of prognostic factors. Largely because of these limitations, the role of surgery in long-term survival has not been adequately studied. METHODS: Data were collected prospectively from 426 patients with infective endocarditis. Variables associated with surgery in patients who did not have intracardiac devices who had left-side-associated valvular infections were determined using multivariable analysis. Propensity scores were then assigned to each patient based on the likelihood of undergoing surgery. Using individual propensity scores, 51 patients who received medical and surgical treatment were matched with 51 patients who received medical treatment only. RESULTS: The following factors were statistically associated with surgical therapy: age, transfer from an outside hospital, evidence of infective endocarditis on physical examination, the presence of infection with staphylococci, congestive heart failure, intracardiac abscess, and undergoing hemodialysis without a chronic catheter. After adjusting for surgical selection bias by propensity score matching, regression analysis of the matched cohorts revealed that surgery was associated with decreased mortality (hazard ratio, 0.27; 95% confidence interval, 0.13-0.55). A history of diabetes mellitus (hazard ratio, 4.81; 95% confidence interval, 2.41-9.62), the presence of chronic intravenous catheters at the beginning of the episode (hazard ratio, 2.65; 95% confidence interval, 1.31-5.33), and paravalvular complications (hazard ratio, 2.16; 95% confidence interval, 1.06-4.44) were independently associated with increased mortality. CONCLUSIONS: Differences between clinical characteristics of patients with infective endocarditis who receive medical therapy versus patients who receive surgical and medical therapy are paramount. After controlling for inherent treatment selection bias and imbalances in prognostic factors using propensity score methodology, risk factors associated with increased long-term mortality included diabetes mellitus, the presence of a chronic catheter at the onset of infection, and paravalvular complications. In contrast, surgical therapy was associated with a significant long-term survival benefit.

Adult↗
PubMed2006

Increased case-fatality rate associated with outbreaks of Neisseria meningitidis infection, compared with sporadic meningococcal disease, in the United States, 1994-2002.

BACKGROUND: Outbreaks of meningococcal disease are infrequent but important public health events. We characterize outbreak-associated cases in the United States and compare them with sporadic disease. METHODS: Outbreaks of meningococcal disease that occurred during the period of 1 July 1994 through 30 June 2002 were identified through state health departments, Centers for Disease Control and Prevention records, and a review of newspapers and the medical literature. Cases associated with outbreaks were compared with sporadic cases identified through population-based surveillance. RESULTS: We identified 69 outbreaks of Neisseria meningitidis infection (median, 9.5 outbreaks per year; range, 3-14 outbreaks per year), which involved 229 patients from 30 states. Forty-three (62%) of the outbreaks involved N. meningitidis serogroup C, 17 (25%) involved serogroup B, and 9 (13%) involved serogroup Y. Twenty-five outbreaks (36%) occurred in communities, and 44 (64%) were organization based, including 12 that occurred in colleges and universities, 19 that occurred in primary and secondary schools, and 8 that occurred in nursing homes. Vaccination campaigns (with the A/C/Y/W-135 meningococcal polysaccharide vaccine) were conducted for 31 outbreaks (28 involving serogroup C and 3 involving serogroup Y). After controlling for age, serogroup, and clinical presentation, outbreak-associated cases were associated with a higher case-fatality rate than were sporadic cases (21% vs. 11%; odds ratio, 3.3; 95% confidence interval, 2.0-5.5). CONCLUSIONS: Outbreaks remain an important but infrequent public health issue, representing <2% of all cases of meningococcal disease. However, given the increased case-fatality rate found among outbreak-related cases of N. meningitidis infection, additional investigation of factors that favor the transmission and virulence of outbreak-related strains is warranted.

Adolescent↗
PubMed2006

Emergence of Salmonella enterica serotype Paratyphi A as a major cause of enteric fever in Kathmandu, Nepal.

We performed pulsed-field gel electrophoresis (XbaI) on 114 bloodstream isolates of Salmonella enterica serotype Paratyphi A and S. enterica serotype Typhi collected from febrile patients in Kathmandu, Nepal. Of the 56 S. Paratyphi A isolates, 51 (91%) were indistinguishable, which suggests the emergence of a single clone. In contrast, only 21 (36%) of the 58 S. Typhi isolates exhibited a common genotype, which is consistent with endemic disease from multiple sources.

Adolescent↗
PubMed2006

Use of sentinel laboratories by clinicians to evaluate potential bioterrorism and emerging infections.

With the persistent threat of emerging infectious diseases and bioterrorism, it has become increasingly important that clinicians be able to identify the diseases that might signal the occurrence of these unusual events. Essential to a thoughtful diagnostic approach is understanding when to initiate a public health investigation and how to appropriately use commonly performed microbiology procedures in the sentinel laboratory to evaluate potential pathogens. Although diagnostic test development is evolving rapidly, recognizing many of these pathogens continues to challenge the capabilities of most sentinel laboratories. Therefore, effective, ongoing communication and education among clinicians, infection control personnel, sentinel laboratorians, public health authorities, and Laboratory Response Network reference laboratorians is the key to preparedness.

Algorithms↗
PubMed2006

West Nile virus among hospitalized, febrile patients: a case for expanding diagnostic testing.

In Georgia, most individuals reported with West Nile virus (WNV) disease have been diagnosed with West Nile neuroinvasive disease (WNND). Relatively few cases of West Nile Fever (WNF) are reported, and the burden of illness due to WNV is likely underestimated. From July through October 2003, WNV serologic testing was performed on enrolled patients>or=18 years of age with fever admitted to a large, urban hospital in Atlanta, Georgia through the emergency department (ED). Patients' history, clinical, and laboratory data were recorded. Residual blood drawn in the ED was tested to determine the presence of WNV IgG and IgM antibodies. Of 254 patients tested for WNV, four (1.6%) patients were positive for WNV IgM and IgG antibodies, and had a clinical illness compatible with WNV. None of the four positive patients were clinically suspected of having WNV infection; discharge diagnoses included pneumonia, migraine, stroke, and gout. These four patients accounted for 80% of all WNV diagnosed in this hospital, 44% of all cases in Fulton County, and 7% of all cases reported in Georgia in 2003. The occurrence of WNV disease may be substantially greater than currently reflected in disease statistics in Georgia and many other states. When indicators of WNV activity are present and patients are likely to have had intensive mosquito exposure, WNV should be considered in the differential diagnosis of seriously ill, febrile patients.

Adolescent↗
PubMed2005

Repeat infective endocarditis: differentiating relapse from reinfection.

Repeat infective endocarditis due to the same species can represent relapse of the initial infection or a new infection. We used time-based clinical criteria and pulsed-field gel electrophoresis-based molecular criteria to classify 13 cases of repeat infective endocarditis as either relapse or reinfection. The agreement between clinical and molecular criteria was imperfect (agreement in 10 [77%] of 13 cases).

Endocarditis, Bacterial↗
PubMed2005

Risk factors for hematogenous complications of intravascular catheter-associated Staphylococcus aureus bacteremia.

BACKGROUND: The role of both host and pathogen characteristics in hematogenous seeding following Staphylococcus aureus bacteremia is incompletely understood. METHODS: Consecutive patients with intravascular catheter-associated Staphylococcus aureus bacteremia were prospectively recruited over a 91-month period. The corresponding bloodstream isolates were examined for the presence of 35 putative virulence determinants. Patient and bacterial characteristics associated with the development of hematogenous complications (HCs) (i.e., septic arthritis, vertebral osteomyelitis, or endocarditis) were defined. RESULTS: HC occurred in 42 (13%) of 324 patients. Patient characteristics at diagnosis that were associated with HC included community onset (relative risk [RR], 2.25; 95% confidence interval [CI], 1.24-4.07; P=.007), increased symptom duration (odds ratio for each day, 1.14; 95% CI, 1.06-1.2; P<.001), presence of a long-term intravascular catheter or noncatheter prosthesis (RR, 4.02; 95% CI, 1.74-9.27; P<.001), hemodialysis dependence (RR, 3.84; 95% CI, 2.08-7.10; P<.001), and higher APACHE II score (P=.02). Bacterial characteristics included sea (RR, 2.03; 95% CI, 1.16-3.55; P=.011) and methicillin-resistant S. aureus (MRSA) (RR, 2.09; 95% CI, 1.19-3.67; P=.015). Subsequent failure to remove a catheter was also associated with HC (RR, 2.28; 95% CI, 1.22-4.27; P=.011). On multivariable analysis, symptom duration, hemodialysis dependence, presence of a long-term intravascular catheter or a noncatheter device, and infection with MRSA remained significantly associated with HC. CONCLUSIONS: This investigation identifies 4 host- and pathogen-related risk factors for hematogenous bacterial seeding and reaffirms the importance of prompt catheter removal.

Adult↗
PubMed2005

Controlled clinical comparison of plastic versus glass bottles of BacT/ALERT PF medium for culturing blood from children.

The plastic pediatric BacT/ALERT (bioMérieux, Durham, N.C.) PF (PPF) is a new nonvented aerobic culture medium in a clear plastic bottle designed to prevent breakage. We compared the performance of the new PPF bottle to that of the present glass BacT/ALERT PF bottle for the recovery of microorganisms as well as for the time to detection of growth in samples of blood obtained for culture from children. We found that the PPF and PF bottles were comparable for recovery of microorganisms and that the safety advantage of plastic bottles can be achieved without compromising performance.

Bacteremia↗
PubMed2005

Controlled clinical comparison of plastic and glass bottles of BacT/ALERT FA medium for culturing organisms from blood of adult patients.

A new, clear-plastic nonvented aerobic FA bottle, designed to prevent breakage, has been developed for the BacT/ALERT blood culture system. We assessed the new plastic FA bottle by comparing its performance with that of the current glass FA bottle for recovery of microorganisms and time to detection of growth in blood samples obtained for culture from adult patients with suspected bloodstream infections. We conclude that the BacT/ALERT plastic and glass FA bottles are comparable for recovery of microorganisms and that the safety advantage of plastic bottles can be achieved without compromising performance.

Adult↗
PubMed2005

Streptococcus pneumoniae antigen test using positive blood culture bottles as an alternative method to diagnose pneumococcal bacteremia.

Recovery of Streptococcus pneumoniae from positive blood culture bottles may be difficult due to autolysis of pneumococci. Therefore, we evaluated the performance of the Binax NOW S. pneumoniae antigen test with samples from positive blood culture bottles and defined the duration of detectable pneumococcal antigen in these bottles. Use of the S. pneumoniae antigen test is an alternative method for identifying S. pneumoniae from positive blood culture bottles and may enable a diagnosis of pneumococcal bacteremia despite negative subcultures.

Antigens, Bacterial↗
PubMed2004

Virulence associated with outbreak-related strains of Burkholderia cepacia complex among a cohort of patients with bacteremia.

The Burkholderia cepacia complex includes 9 genomovars. The relative virulence of each is unknown. Host and pathogen features associated with mortality were evaluated among patients with B. cepacia complex bacteremia. Cases were ascertained through review of blood culture results for the period of May 1996 through May 2002. Isolates were identified to species level with 16S rDNA and recA-based species-specific polymerase chain reaction analyses and recA restriction fragment-length polymorphism. Strain typing was performed with pulsed-field gel electrophoresis. Fifty-three patients with B. cepacia complex bacteremia were identified; only 9 (17%) had cystic fibrosis. Twenty-five patients (47%) died within 14 days of bacteremia. After controlling for comorbid conditions and therapeutic interventions, 2 outbreak-related strains of Burkholderia cenocepacia (genomovar III) were associated with 14-day mortality (odds ratio, 5.5; 95% confidence interval, 1.20-25.02). B. cenocepacia is an emerging nosocomial pathogen. Certain strains are associated with an enhanced capacity for interpatient spread and poor outcome.

Adolescent↗
PubMed2004

Antibacterial susceptibility testing in the clinical laboratory.

This article familiarizes the clinician with the principles of bacterial susceptibility testing and reporting to facilitate communication with the clinical microbiology laboratory. The emergence of resistance in nearly all commonly isolated bacterial organisms has highlighted the need for ongoing dialogue between the laboratory and those who use its services.

Humans↗
PubMed2004

Sacral tuberculosis: a case report and review of the literature.

BACKGROUND: We present a patient with a heterogeneously enhancing lesion within the body of the sacrum and the sacral canal. Sacral tuberculosis (TB) was suspected because of a history of familial exposure. Few cases isolated to the sacrum have been reported in the literature. The characteristic histopathologic and magnetic resonance imaging (MRI) findings are also presented. CASE DESCRIPTION: A 31-year-old African-American male presented with an 8-month history of lower back pain radiating into his legs as well as numbness and weakness of the right foot. His history revealed PPD conversion following an exposure to active pulmonary TB 3 years prior for which he received 6 months of isoniazid prophylaxis. An MRI scan revealed a large heterogeneously enhancing lesion involving the sacrum with extension into the sacral canal. The patient underwent computed tomography (CT)- guided needle biopsy of the sacral lesion. Cytopathologic examination revealed caseating granulomas. Acid-fast bacilli cultures were positive for Mycobacterium tuberculosis. He was placed on a 6-month course of isoniazid, rifampin, pyrazinamide, and ethambutol. At 3-month follow-up, his examination and symptoms had improved. CONCLUSIONS: Sacral TB is an extremely rare cause of lower back pain with radiation into the lower extremities. TB should always be considered in the differential diagnosis of isolated sacral masses, especially in light of today's increasing multidrug resistance and immunosuppressed population.

Adult↗
PubMed2004

The etiology of febrile illness in adults presenting to Patan hospital in Kathmandu, Nepal.

In Nepal, many infections remain poorly characterized, partly due to limited diagnostic facilities. We studied consecutive febrile adults presenting to a general hospital in Kathmandu, Nepal. Of the 876 patients enrolled, enteric fever and pneumonia were the most common clinical diagnoses. Putative pathogens were identified in 323 (37%) patients, the most common being Salmonella enterica serotype Typhi and S. enterica serotype Paratyphi A (117), Rickettsia typhi (97), Streptococcus pneumoniae (53), Leptospira spp. (36), and Orientia tsutsugamushi (28). Approximately half of the Salmonella isolates were resistant to nalidixic acid. No clinical predictors were identified to reliably distinguish between the different infections. These findings confirm the heavy burden of enteric fever and pneumonia in Kathmandu, and highlight the importance of murine typhus, scrub typhus, and leptospirosis. Given the lack of reliable clinical predictors, the development of cheap and accurate diagnostic tests are likely to be of great clinical utility in this setting.

Adolescent↗