The Microbial Etiology of Community-Acquired Pneumonia in Adults: from Classical Bacteriology to Host Transcriptional Signatures.

All modern advances notwithstanding, pneumonia remains a common infection with substantial morbidity and mortality. Understanding of the etiology of pneumonia continues to evolve as new techniques enable identification of already known organisms and as new organisms emerge. We now review the etiology of pneumonia (at present often called "community-acquired pneumonia") beginning with classic bacteriologic techniques, which identified Streptococcus pneumoniae as the overwhelmingly common cause, to more modern bacteriologic studies, which emphasize Haemophilus influenzae, Staphylococcus aureus, Moraxella catarrhalis, , Pseudomonas, and normal respiratory flora.

A prospective surveillance study to determine the prevalence of 16S rRNA methyltransferase-producing Gram-negative bacteria in the UK.

Objectives: To determine the prevalence of 16S rRNA methyltransferase- (16S RMTase-) producing Gram-negative bacteria in patients in the UK and to identify potential risk factors for their acquisition.

Methods: A 6 month prospective surveillance study was conducted from 1 May to 31 October 2016, wherein 14 hospital laboratories submitted Acinetobacter baumannii, Enterobacterales and Pseudomonas aeruginosa isolates that displayed high-level amikacin resistance according to their testing methods, e.g.

Two cases of imported respiratory diphtheria in Edinburgh, Scotland, October 2019.

We report two cases of respiratory toxigenic Corynebacterium diphtheriae infection in fully vaccinated UK born adults following travel to Tunisia in October 2019. Both patients were successfully treated with antibiotics and neither received diphtheria antitoxin. Contact tracing was performed following a risk assessment but no additional cases were identified.

Comparison of Unyvero P55 Pneumonia Cartridge, in-house PCR and culture for the identification of respiratory pathogens and antibiotic resistance in bronchoalveolar lavage fluids in the critical care setting.

Faster respiratory pathogen detection and antibiotic resistance identification are important in critical care due to the severity of illness, significant prior antibiotic exposure and infection control implications. Our objective was to compare the performance of the commercial Unyvero P55 Pneumonia Cartridge (Curetis AG) with routine bacterial culture methods and in-house bacterial multiplex real-time PCR assays. Seventy-four bronchoalveolar lavage specimens from patients admitted to a Scottish intensive care unit (ICU) over a 33-month period were tested prospectively by routine culture and viral PCR and retrospectively by Unyvero P55 and in-house bacterial PCR.

16S pan-bacterial PCR can accurately identify patients with ventilator-associated pneumonia.

Unlabelled: Ventilator-associated pneumonia (VAP) remains a challenge to intensive care units, with secure diagnosis relying on microbiological cultures that take up to 72 hours to provide a result. We sought to derive and validate a novel, real-time 16S rRNA gene PCR for rapid exclusion of VAP. Bronchoalveolar lavage (BAL) was obtained from two independent cohorts of patients with suspected VAP.

Comprehensive Molecular Testing for Respiratory Pathogens in Community-Acquired Pneumonia.

Background: The frequent lack of a microbiological diagnosis in community-acquired pneumonia (CAP) impairs pathogen-directed antimicrobial therapy. This study assessed the use of comprehensive multibacterial, multiviral molecular testing, including quantification, in adults hospitalized with CAP.

Methods: Clinical and laboratory data were collected for 323 adults with radiologically-confirmed CAP admitted to 2 UK tertiary care hospitals.

Molecular diagnosis of Legionella infections--Clinical utility of front-line screening as part of a pneumonia diagnostic algorithm.

Objectives: Urinary antigen testing for Legionella pneumophila serogroup 1 is the leading rapid diagnostic test for Legionnaires' Disease (LD); however other Legionella species and serogroups can also cause LD. The aim was to determine the utility of front-line L. pneumophila and Legionella species PCR in a severe respiratory infection algorithm.

Comparative evaluation of the Diagenode multiplex PCR assay on the BD max system versus a routine in-house assay for detection of Bordetella pertussis.

This study looked at 128 nasopharyngeal aspirates (NPA) and 162 throat swabs (TS) tested with the Diagenode multiplex assay on the BD Max system versus our in-house Bordetella pertussis PCR. Sensitivity and specificity were 97.3% and 100% for NPA and 88.

Clinical outcomes and macrolide resistance in Mycoplasma pneumoniae infection in Scotland, UK.

Mycoplasma pneumoniae has a cyclical, epidemic pattern of infection and the most recent epidemic occurred in Europe in 2011. Macrolides are recommended for the treatment of M. pneumoniae respiratory tract infection, but macrolide resistance has been reported at low levels in Europe.

Comparison of the Luminex Respiratory Virus Panel fast assay with in-house real-time PCR for respiratory viral infection diagnosis.

The Luminex xTAG Respiratory Virus Panel (RVP) assay has been shown to offer improved diagnostic sensitivity over traditional viral culture methods and to have a sensitivity comparable to those of individual real-time nucleic acid tests for respiratory viruses. The objective of this retrospective study was to test a new, streamlined version of this assay, the RVP Fast assay, which requires considerably less run time and operator involvement. The study compared the performance of the RVP Fast assay with those of viral culture, a direct fluorescent assay (DFA), and a panel of single and multiplex real-time PCRs in the testing of 286 respiratory specimens submitted to the Edinburgh Specialist Virology Centre for routine diagnosis of viral infection between December 2007 and February 2009.

A study on pathogenicity and mosquito transmission success in the rodent malaria parasite Plasmodium chabaudi adami.

We investigated the parasitology, pathogenicity (virulence) and infectivity to mosquitoes of blood infections in mice, of two strains, DS and DK, of the rodent malaria parasite Plasmodium chabaudi adami. Blood infections of DS were found to be highly pathogenic; the asexual parasites in these infections were fast-growing and showed no evidence of selectivity in their infection of host erythrocytes. In contrast to DS, blood infections of DK were much less pathogenic; the asexual parasites were slower-growing and showed a moderate degree of selectivity to a subset of erythrocytes which were not reticulocytes.