Transcriptomic Fingerprint of Bacterial Infection in Lower Extremity Ulcers

Clinicians and researchers utilize subjective classification systems based on clinical parameters to stratify lower extremity ulcer infections for treatment and research. This study compared clinical infection classifications (mild to severe) of lower extremity ulcers (n = 44) with transcriptomic profiles and direct measurement of bacterial RNA signatures by RNA-sequencing. Samples demonstrating similar transcriptomes were clustered and characterized by transcriptomic fingerprint. Clinical infection severity did not explain the major sources of variability among the samples and samples with the same clinical classification demonstrated high inter-sample variability. High proportions of bacterial RNA, however, resulted in a strong effect on transcription and increased expression of genes associated with immune response and inflammation. K-means clustering identified two clusters of samples, one of which contained all of the samples with high levels of bacterial RNA. A support vector classifier identified a fingerprint of 20 genes, including immune-associated genes such as CXCL8, GADD45B, and HILPDA, which accurately identified samples with signs of infection via cross-validation. This suggests that stratification of infection states based on a transcriptomic fingerprint may be a useful tool for studying host-bacterial interactions in these ulcers, as well as an objective classification method to identify the severity of infection.

INFLUENCE OF PATIENT’S GENERAL HEALTH STATUS ON THE OUTCOME OF INFECTIONS

The outcomes of a pathogen colonization and development of clinical infection can be strictly related to the general health status of a patient. The spread of the awareness about the dangers of underlying health conditions should be the main role of the conventional medicine, as well as the key to successful treatments and control of diseases.

Study on Ultrasonic Imaging of Nursing Care for Preventing and Treating Clinical Infection of Hemodialysis Patients Based on Smart Medical Big Data

The ultrasonic imaging research of nursing care for preventing and treating clinical infection of hemodialysis patients based on smart medical big data is studied. 100 hemodialysis patients were selected from May 2019 to May 2020. The patients were randomly divided into the observation group and routine group with 50 cases in each group. The PWV of common carotid artery was measured by ultrasonic rapid imaging technology, including BS value at the beginning of systole and ES value at the end of systole. According to the effect of preventive nursing intervention of intelligent medical treatment, the MHD group adopted preventive nursing intervention, while the routine group adopted traditional nursing service. The infection rate and quality of life score of patients in both groups were evaluated. The results showed that there were significant differences in BS and ES values between the MHD group and PWV in the normal group ( P < 0.05 ). There was no significant difference in BS value and ES value between MHD patients with plaque and those without plaque ( P > 0.05 ). It is proved that the ultrafast ultrasound imaging technology is safe, simple, noninvasive, nonradioactive, and fast and can automatically and accurately detect carotid PWV. It is expected to become a new imaging method for quantitative evaluation of arteriosclerosis degree in MHD patients. Preventive nursing intervention can reduce the incidence of infection in hemodialysis patients and improve their quality of life. Smart medical treatment has brought us a lot of convenience. As patients, we should change our concept, actively participate in it, and contribute to the development of smart medical treatment.

Influenza A Virus Defective Viral Genomes Are Inefficiently Packaged into Virions Relative to Wild-Type Genomic RNAs

Defective interfering particles (DIPs) are commonly produced by RNA viruses and have been implicated in modulating clinical infection outcomes; hence, there is increasing interest in the potential of DIPs as antiviral therapeutics. For influenza viruses, DIPs are formed by the packaging of genomic RNAs harboring internal deletions.

788. Enterobacter cloacae Infection Characteristics and Outcomes in Military Personnel who Sustained Trauma in Iraq and Afghanistan

Background Enterobacter cloacae is a Gram-negative rod with chromosomally-induced Amp-C β-lactamase with multidrug-resistant potential. Joint Trauma System guidelines for treating combat wounds include prophylaxis with cefazolin and ertapenem, potent inducers of Amp-C. We evaluated clinical characteristics, antibiotic utilization, and outcomes associated with battlefield-related E. cloacae infections. Methods All initial solitary (those with single isolates) and serial E. cloacae isolates (≥24 hours from initial isolate from any site) were collected from the Trauma Infectious Disease Outcomes Study (6/2009-12/2014). Inclusion required E. cloacae isolation from a clinical infection. Amp-C-inducing β-lactams were classified based on induction potential and lability to the Amp-C β-lactamase as Amp-C induction levels. Results Of 653 E. cloacae isolates, 253 met inclusion criteria – 64 patients had only initial isolates, 54 patients had serial isolates. Patients were largely male (99%), median age 23 years (IQR 21-27), with injury severity score of 34 (IQR 24-45). Initial isolates were wound (70%), respiratory (22%), blood (7%), urine (1%), and other (1%). Patients commonly had blast injuries (89%), required ICU admission (95%), and had a median hospital stay of 57 days (IQR 39-82). Patients with serial isolates showed a trend towards earlier clinical infection (5 vs 8 days, P = 0.07). They were also less likely to receive carbapenems prior to E. cloacae isolation compared to those with only initial isolates (4% vs 38%) and more likely to receive 1st generation cephalosporins (79% vs 58%, P = 0.01). The serial isolate group received more days of 1st generation cephalosporins (median 6 days vs 2.5 days, P = 0.01). Cumulative antimicrobial therapy trended towards significance and was greater with the serial isolates (median 100 days vs 74 days, P = 0.08). There was no difference in number of surgical interventions between those with and without serial isolates (P = 0.54). Overall, 6 patients died. Conclusion E. cloacae infections after battlefield trauma were frequently encountered and associated with exposure to 1st generation cephalosporins. Serial infections did not correlate to worse patient outcomes but displayed a trend towards an overall greater duration of antibiotic use. Disclosures William N. Bennett, V, MD, Abbvie (Shareholder)Amgen (Shareholder)Nabriva (Shareholder)

Severe lung infection and septicemia caused by Paludibacterium purpuratum---a case report and evaluation of bacterial traits

Paludibacterium species are gram-stain negative rods, facultatively anaerobic, and have been isolated from wetland soil. Clinical infection caused by this genus is rarely reported. We reported an 84-year-old woman with chronic renal disease and hypertension acquired P. purpuratum lung infection and septicemia in southern Taiwan.

Blood Transcriptomes of Anti-SARS-CoV-2 Antibody-Positive Healthy Individuals Who Experienced Asymptomatic Versus Clinical Infection

The reasons behind the clinical variability of SARS-CoV-2 infection, ranging from asymptomatic infection to lethal disease, are still unclear. We performed genome-wide transcriptional whole-blood RNA sequencing, bioinformatics analysis and PCR validation to test the hypothesis that immune response-related gene signatures reflecting baseline may differ between healthy individuals, with an equally robust antibody response, who experienced an entirely asymptomatic (n=17) versus clinical SARS-CoV-2 infection (n=15) in the past months (mean of 14 weeks). Among 12.789 protein-coding genes analysed, we identified six and nine genes with significantly decreased or increased expression, respectively, in those with prior asymptomatic infection relatively to those with clinical infection. All six genes with decreased expression (IFIT3, IFI44L, RSAD2, FOLR3, PI3, ALOX15), are involved in innate immune response while the first two are interferon-induced proteins. Among genes with increased expression six are involved in immune response (GZMH, CLEC1B, CLEC12A), viral mRNA translation (GCAT), energy metabolism (CACNA2D2) and oxidative stress response (ENC1). Notably, 8/15 differentially expressed genes are regulated by interferons. Our results suggest that subtle differences at baseline expression of innate immunity-related genes may be associated with an asymptomatic disease course in SARS-CoV-2 infection. Whether a certain gene signature predicts, or not, those who will develop a more efficient immune response upon exposure to SARS-CoV-2, with implications for prioritization for vaccination, warrant further study.

Chronic Urinary Infection in Overactive Bladder Syndrome: A Prospective, Blinded Case Control Study

ObjectivesTo investigate whether women with overactive bladder (OAB) symptoms and no evidence of clinical infection by conventional clean-catch midstream urine cultures have alternative indicators of sub-clinical infection.Patients/Subjects, Materials &amp; MethodsThe study was a prospective, blinded case-control study with 147 participants recruited, including 73 OAB patients and 74 controls. The OAB group comprised female patients of at least 18 years of age who presented with OAB symptoms for more than 3 months. Clean-catch midstream urine samples were examined for pyuria by microscopy; subjected to routine and enhanced microbiological cultures and examined for the presence of 10 different cytokines, chemokines, and prostaglandins by ELISA.ResultsThe mean age and BMI of participants in both groups were similar. No significant difference in the number of women with pyuria was observed between OAB and control groups (p = 0.651). Routine laboratory cultures were positive in three (4%) of women in the OAB group, whereas the enhanced cultures isolated bacteria in 17 (23.2%) of the OAB patients. In the control group, no positive cultures were observed using routine laboratory cultures, whereas enhanced culture isolated bacteria in 8 (10.8%) patients. No significant differences were observed in the concentrations of PGE2, PGF2α, MCP-1, sCD40L, MIP-1β, IL12p70/p40, IL12/IL-23p40, IL-5, EGF and GRO-α between the OAB and control groups.ConclusionsPatients with OAB symptoms have significant bacterial growth on enhanced culture of the urine, which is often not detectable through routine culture, suggesting a subclinical infection. Enhanced culture techniques should therefore be used routinely for the effective diagnosis and management of OAB.