Multicentre evaluation of two multiplex PCR platforms for the rapid microbiological investigation of nosocomial pneumonia in UK ICUs: the INHALE WP1 study

BackgroundCulture-based microbiological investigation of hospital-acquired or ventilator-associated pneumonia (HAP or VAP) is insensitive, with aetiological agents often unidentified. This can lead to excess antimicrobial treatment of patients with susceptible pathogens, while those with resistant bacteria are treated inadequately for prolonged periods. Using PCR to seek pathogens and their resistance genes directly from clinical samples may improve therapy and stewardship.MethodsSurplus routine lower respiratory tract samples were collected from intensive care unit patients about to receive new or changed antibiotics for hospital-onset lower respiratory tract infections at 15 UK hospitals. Testing was performed using the BioFire FilmArray Pneumonia Panel (bioMérieux) and Unyvero Pneumonia Panel (Curetis). Concordance analysis compared machine and routine microbiology results, while Bayesian latent class (BLC) analysis estimated the sensitivity and specificity of each test, incorporating information from both PCR panels and routine microbiology.FindingsIn 652 eligible samples; PCR identified pathogens in considerably more samples compared with routine microbiology: 60.4% and 74.2% for Unyvero and FilmArray respectively vs 44.2% by routine microbiology. PCR tests also detected more pathogens per sample than routine microbiology. For common HAP/VAP pathogens, FilmArray had sensitivity of 91.7%–100.0% and specificity of 87.5%–99.5%; Unyvero had sensitivity of 50.0%–100.0%%, and specificity of 89.4%–99.0%. BLC analysis indicated that, compared with PCR, routine microbiology had low sensitivity, ranging from 27.0% to 69.4%.InterpretationConventional and BLC analysis demonstrated that both platforms performed similarly and were considerably more sensitive than routine microbiology, detecting potential pathogens in patient samples reported as culture negative. The increased sensitivity of detection realised by PCR offers potential for improved antimicrobial prescribing.

Cellulitis in children: a retrospective single centre study from Australia

AimTo characterise the epidemiology, clinical features and treatment of paediatric cellulitis.MethodsA retrospective study of children presenting to a paediatric tertiary hospital in Western Australia, Australia in 2018. All inpatient records from 1 January to 31 December 2018 and emergency department presentations from 1 July to 31 December 2018 were screened for inclusion.Results302 episodes of cellulitis were included comprising 206 (68.2%) admitted children and 96 (31.8%) non-admitted children. The median age was 5 years (IQR 2–9), 40 (13.2%) were Aboriginal and 180 (59.6%) boys. The extremities were the most commonly affected body site among admitted and non-admitted patients. There was a greater proportion of facial cellulitis in admitted patients (27.2%) compared with non-admitted patients (5.2%, p<0.01). Wound swab was the most frequent microbiological investigation (133/302, 44.0%), yielding positive cultures in the majority of those tested (109/133, 82.0%). The most frequent organisms identified were Staphylococcus aureus (94/109, 86.2%) (methicillin-susceptible S. aureus (60/94, 63.8%), methicillin-resistant S. aureus) and Streptococcus pyogenes (22/109, 20.2%) with 14 identifying both S. aureus and S. pyogenes. Intravenous flucloxacillin was the preferred antibiotic (154/199, 77.4%), with median intravenous duration 2 days (IQR 2–3), oral 6 days (IQR 5–7) and total 8 days (IQR 7–10).ConclusionsCellulitis is a common reason for presentation to a tertiary paediatric hospital. We confirm a high prevalence of extremity cellulitis and demonstrate that children with facial cellulitis often require admission. Cellulitis disproportionately affected Aboriginal children and children below 5 years. Prevention of cellulitis involves early recognition and treatment of skin infections such as impetigo and scabies.

Chlamydiosis of dogs and cats in in modern cities

The aim of the research was to conduct an in-depth analysis of the investigation of chlamydial infections occurred in cats and dogs in Kyiv during the last 10 years. The article includes three main directions of investigation: 1) The analysis of the epizootic situation with chlamydiosis; 2) Microbiological investigation and 3) Serological monitoring. The clinical and epizootiological studies of chlamydiosis of dogs and cats have been looked into, with the focus on differences and similarities in age and sex of diseased animals. We have investigated 3334 animals (1351 dogs and 1983 cats), including 721 animals (107 dogs and 614 cats) with the manifestation of clinical signs specific to chlamydia. During the investigation 11 isolates of Chlamydia spp. were obtained from the infected animals. Additionally, immune and biological peculiarities have been analyzed. Due to serological monitoring within the epizootiological uncontrolled experiment, a satisfactory level of protection of cats (63%) vaccinated against chlamydiosis has been reached, as well as the possibility of the persistence of the pathogen in unvaccinated animals (9%).

Keratitis due to a Rare Fungus Colletotrichum dematium: A Case Report

Keratitis is a very serious clinical condition caused by bacteria, fungi or parasites. It is associated with serious complications like blindness or endophthalmitis if remained undiagnosed. A 42-year-old male patient with the history of foreign body inoculation presented with mild pain and redness. After clinical examination, fungal keratitis was diagnosed. Corneal scrapping was sent for microbiological investigation. A very rare fungi Colletotrichum dematium was isolated and identified. Patient was managed with Natamycin tab fluconazole and atropin eye drops. To know the geographical distribution of the rare fungi, more and more cases should be studied and reported, which will help in management of rare fungi and standardisation of therapy.

Multicentre evaluation of two multiplex PCR platforms for the rapid microbiological investigation of nosocomial pneumonia in UK ICUs: the INHALE WP1 study

SummaryBackgroundICU patients with hospital-acquired or ventilator-associated pneumonia (HAP or VAP) have high mortality, so broad-spectrum antibiotics are initiated at clinical diagnosis, then refined after 2-3 days, once microbiology results become available. Unfortunately, culture-based microbiological investigation is also insensitive, with aetiological agents remaining unidentified in many cases. This leads to extended over-treatment of patients with susceptible pathogens, whilst those with highly-resistant pathogens are treated inadequately for prolonged periods. Using PCR to seek pathogens and their resistance genes directly from clinical samples may improve therapy and stewardship. The INHALE study compared two PCR platforms for HAP/VAP diagnosis against routine microbiology (RM), identifying one to progress into a Randomised Controlled Trial (RCT).MethodsSurplus routine sputa, endotracheal tube exudates and bronchoalveolar lavages were collected from ICU patients about to receive new or changed antibiotics for hospital-onset lower respiratory tract infections at 15 UK hospitals. Samples were tested (or frozen for testing) within 72h of collection. Testing was performed using the BioFire FilmArray Pneumonia Panel (bioMérieux) and Unyvero Pneumonia Panel (Curetis). Agreement between machine- and RM-results was categorised as ‘full positive/negative concordance’, ‘partial concordance’ or ‘major/minor discordance’. Bayesian latent class (BLC) analysis was used to estimate the sensitivity and specificity of each test, incorporating information from both PCR panels, 16S rDNA analysis and RM.FindingsIn 652 eligible samples; PCR identified pathogens in considerably more samples compared with RM: 60.4% and 74.2% for Unyvero and FilmArray respectively vs. 44.2%. Both tests also recorded more organisms per sample than routine culture, with the two PCR tests frequently in agreement with each other. For common HAP/VAP pathogens, FilmArray had sensitivity of 91.7-100.0% and specificity of 87.5-99.5%; Unyvero had sensitivity of 83.3-100.0%% except for Klebsiella aerogenes (50.0%) and Serratia marcescens (77.8%), and specificity of 89.4-99.0%. BLC analysis indicated that, compared with PCR, RM had low sensitivity, ranging from 27.0% to 69.4% for common respiratory pathogens. PCR detected more high-consequence antimicrobial resistance genes than would have been predicted by RM and susceptibility testing; around half the host strains could be detected when culture was repeated and they were sought assiduously.InterpretationConventional and BLC analysis demonstrated that both platforms performed similarly and were considerably more sensitive than RM, detecting potential pathogens in patient samples reported as culture negative. FilmArray had slightly higher sensitivity than Unyvero for common pathogens and was chosen for INHALE’s RCT, based on the balance of these results, a swifter turnaround time (75 min vs. 6h), and a smaller footprint. The increased sensitivity of detection realised by PCR offers potential for improved antimicrobial prescribing.