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A novel G8363A mutation in the mtDNA tRNA(Lys) gene was associated, in two unrelated families, with a syndrome consisting of encephalomyopathy, sensorineural hearing loss, and hypertrophic cardiomyopathy. Muscle biopsies from the probands showed mitochondrial proliferation and partial defects of complexes I, III, and IV of the electron-transport chain. The G8363A mutation was very abundant (>95%) in muscle samples from the probands and was less copious in blood from 18 maternal relatives (mean 81.3% +/- 8.5%). Single-muscle-fiber analysis showed significantly higher levels of mutant genomes in cytochrome (c) oxidase-negative fibers than in cytochrome (c) oxidase-positive fibers. The mutation was not found in >200 individuals, including normal controls and patients with other mitochondrial encephalomyopathies, thus fulfilling accepted criteria for pathogenicity.

Reprocessing failure of endoscopes may result in outbreaks of serious infections in vulnerable patients caused by Gram-negative bacteria. P. oleovorans (PSOL) was detected in 6 automated endoscope washer-disinfectors (AEWDs) in two reprocessing units during routine check and probing for quality control. Ten endoscopes were probed yielding the growth of PSOL. Two different PSOL strains were identified by genotyping. Biofilms and planktonic cells of both PSOL (N = 2) and of Pseudomonas aeruginosa PAO1 as reference were incubated with increased disinfectant concentrations modelling the disinfection process in the AEWD. PSOL in planktonic form was eradicated by GLUT1% (1 g/100 g) at 55 °C. GLUT at a higher concentration of 3 % resulted in the eradication of PSOL biofilms at 25 °C. The persistent growth of PSOL in quality controls indicates inadequate disinfection. Increase of the concentration of GLUT would be an option to eradicate PSOL. However, increasing the concentration of GLUT may lead to corrosion of the sensible instruments and toxic side-effects in patients. Further investigation on disinfectant type and concentration, the reservoir of contamination and defining additional disinfection steps are warranted., Competing Interests: The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (© 2024 The Authors.)

Background: The COVID-19 pandemic has profoundly challenged societies and healthcare systems in particular. To prevent the spread of SARS-CoV-2, infection prevention and control (IPC) strategies had to be developed on the local, national and international level. The aim of this study is to provide details of the COVID-19 experience at the Vienna General Hospital (VGH) in the context of the national and international COVID-19 response for learning and improvement., Methods: This is a retrospective report, outlining the evolution of IPC measures and challenges encountered at the health facility (VGH), the national (Austria) and global level between February 2020 and October 2022., Results: The IPC strategy at the VGH has been continuously adapted to changes in the epidemiological setting, new legal directives and Austrian by-laws. The current strategy, nationally and internationally, focuses on endemicity rather than maximum transmission risk reduction. For the VGH, this has recently resulted in an increase in COVID-19 clusters. To protect our particularly vulnerable patients, many COVID-19 precautions have been maintained. Barriers to adequate IPC implementation at the VGH and other hospitals include a lack of sufficient isolation options and non-adherence with universal face mask regulations. Globally, misinformation on COVID-19 hampered an effective response., Conclusions: This retrospective analysis of the COVID-19 response at the VGH and international reports underline the need for pandemic preparedness, readiness and response by improving future hospital design and infrastructure, conducting regular trainings for protective attire and increasing health literacy as now recently published in a concise document by WHO., (© 2023. The Author(s).)

The antibacterial efficacy of hydrogen peroxide encapsulated in micelles (mH 2 O 2 ) against biofilms was compared with that of hydrogen peroxide alone and of three commercially available aqueous biocides. The activity of mH 2 O 2 on 24-h biofilms of reference strains of Staphylococcus spp. and Pseudomonas aeruginosa was tested in a static microtiter plate model. The biofilms were incubated with mH 2 O 2 (17% v/v H 2 O 2 , 2% lactic acid, 0.3% phytoextract, H 2 O) and its individual ingredients and compared with three aqueous biocides at different concentrations and times of exposure. After 5-min exposure, 10% mH 2 O 2 (corresponding to 1.7% v/v H 2 O 2 ) achieved > 8 log 10 reductions against all the test strains, while 1.7% H 2 O 2 achieved a maximum of 1.5 log 10 reduction. After 5-min exposure, none of the commercially available biocides tested showed themselves to be capable of completely eliminating the test strains embedded in biofilms. Hydrogen peroxide encapsulated in micelles demonstrated enhanced activity against planktonic cells and biofilms of Staphylococcus spp. and P. aeruginosa .

Background: The Gram-negative bacterium Klebsiella pneumoniae is a frequent pathogen causing outbreaks in neonatal intensive care units. Some Enterobacteriaceae can acquire the ability to sequester iron from infected tissue by secretion of iron-chelating compounds such as yersiniabactin. Here we describe an outbreak and clinical management of infections because of a highly virulent yersiniabactin-producing, nonmultiresistant K. pneumoniae strain in a neonatal intensive care unit. Outbreak investigation and effectiveness assessment of multidisciplinary infection control measurements to prevent patient-to-patient transmission of highly pathogenic K. pneumoniae were undertaken., Methods: Outbreak cases were identified by isolation of K. pneumoniae from blood or stool of infants. Clinical data were abstracted from medical charts. K. pneumoniae isolates were genotyped using whole genome sequencing, and yersiniabactin production was evaluated by luciferase assay., Results: Fourteen cases were confirmed with 8 symptomatic and 6 colonized patients. Symptomatic patients were infants of extremely low gestational and chronologic age with fulminant clinical courses including necrotizing enterocolitis and sepsis. Whole genome sequencing for bacterial isolates confirmed the presence of an outbreak. All outbreak isolates produced yersiniabactin., Conclusions: Yersiniabactin-producing K. pneumoniae can display a high pathogenicity in extremely premature infants with low chronologic age. This outbreak also underlines the considerable potential of today's infection control systems for recognizing and controlling nosocomial infections in highly vulnerable populations.

Background: Endoscopes are well-known sources of bacterial transmission in health care facilities offering endoscopy services. The association between multidrug-resistant bacterial infections in patients who had undergone an endoscopic retrograde cholangiopancreatography procedure with reprocessed duodenoscopes has been much discussed. Bacterial contamination of duodenoscopes has been attributed to difficulties with reprocessing these devices, specifically the distal end of the scope, which features a movable forceps elevator. In light of a recent Food and Drug Administration warning letter to Olympus regarding their closed-channel duodenoscope model TJF-Q180V, the aim of our study was to prospectively evaluate the efficacy and safety of our current reprocessing procedures with regard to the TJF-Q180V duodenoscope models used in our hospital., Methods: From August 2015-March 2016, we prospectively collected microbiologic surveillance samples from 6 TJF-Q180V model duodenoscopes in routine use at the Division of Gastroenterology and Hepatology using the ESwab collection system (COPAN Diagnostics Inc, Murrieta, CA)., Results: A total of 237 microbiologic samples from the forceps elevator were obtained during the survey period. None of the samples yielded microorganism growth., Conclusion: These findings suggest that when following a diligent and validated reprocessing standard in accordance with manufacturer's recommendations, closed-channel endoscope models can still be used. Nevertheless, validated adaptions of current closed-channel duodenoscope models are needed to allow for simple and safe reprocessing. Furthermore, comprehensive postmarket surveillance needs to be established., (Copyright © 2017. Published by Elsevier Inc.)

A novel A7543G mutation was found in the mitochondrial DNA transfer ribonucleic acidAsp gene in an 11-year-old girl with myoclonic seizures, developmental delay, and severe behavioral problems. Muscle histochemistry failed to show any ragged red fibers or cytochrome c oxidase-negative fibers, and muscle biochemistry showed partial cytochrome c oxidase deficiency. The mutation was heteroplasmic in muscle, fibroblasts, and blood from the patient and in blood from other affected family members, and the proportion of mutant mitochondrial DNA correlated with the severity of symptoms.

Four missense mutations have been reported to be associated with the typical, adult form of carnitine palmitoyltransferase II (CPT II) deficiency: Three amino acid substitutions (R631C. P50H and D553N) appear to be rare, while the S113L mutation was found to be common in a group of European patients with CPT II deficiency. We analyzed genomic DNA from 20 American patients with recurrent episodes of myoglobinuria as well as DNA from 10 normal controls in order to determine the frequency of the reported missense mutations in our patient population. The three previously described rare mutations were not found in our group of patients. The S113L mutation was found in 19 of our patients: 5 patients were homozygous, 14 patients were heterozygous. Given the high frequency of this mutation in our series of patients we concluded that the clinical diagnosis of CPT II deficiency can be confirmed by a 'blood test' without resorting to a muscle biopsy.

We analyzed leukocyte DNA from 32 patients with suspected McArdle's disease, 24 of whom had biochemically or histochemically proven myophosphorylase deficiency. We found that 19 were homozygous for the most common mutation at codon 49, 2 were compound heterozygotes, and 1 was a manifesting heterozygote. In six patients, we could find only one mutant allele, suggesting a still unidentified mutation on the second allele. We were unable to identify any of the known mutations in four patients. Our findings indicate that the diagnosis of McArdle's disease can be established in approximately 90% of patients using DNA isolated from leukocytes, thereby avoiding muscle biopsy.