Detection of the epidemic Pseudomonas aeruginosa AUST-03 (ST242) strain in people with cystic fibrosis in South Africa.

INTRODUCTION: Pseudomonas aeruginosa AUST-03 (ST242) has been reported to cause epidemics in people with CF (pwCF) from Australia and has been associated with multidrug resistance and increased morbidity and mortality. Here, we report an epidemic P. aeruginosa (AUST-03) strain in South African pwCF detected at a public hospital and characterize the genomic antibiotic resistance determinants. METHODS: The P. aeruginosa AUST-03 (ST242) study isolates were analysed with whole genome sequencing using the Illumina NextSeq2000 platform. Raw sequencing reads were processed using the Jekesa pipeline and multilocus sequence typing and genomic antibiotic resistance characterization was performed using public databases. Genetic relatedness between the study isolates and global P. aeruginosa ST242 from public databases was determined using a maximum-likelihood phylogenetic tree. Antibiotic susceptibility testing was performed using the disk diffusion and broth microdilution techniques. RESULTS: A total of 11 P. aeruginosa AUST-03 isolates were isolated from two children with CF. The majority (8/11) of these isolates were multidrug-resistant (MDR) or extensively drug resistant; and the multidrug efflux pumps MexAB-OprM, MexCD-OprJ, MexEF-OprN, and MexXY-OprM were the most clinically relevant antibiotic resistance determinants and were detected in all of the isolates. The study isolates were the most closely related to a 2020 P. aeruginosa AUST-03 (ST242) CF isolate from Russia. CONCLUSION: Epidemic MDR P. aeruginosa strains are present at South African public CF clinics and need to be considered when implementing segregation and infection control strategies to prevent possible spread and outbreaks.

Assessment of liver fibrosis markers in people with rheumatoid arthritis on methotrexate.

BACKGROUND: Up to 3% of methotrexate (MTX)-treated rheumatoid arthritis (RA) patients might develop liver fibrosis or cirrhosis, requiring effective screening algorithms. AIMS: To assess the utility of non-invasive liver fibrosis assessment in RA patients on MTX. METHODS: Fifty-six patients were recruited from rheumatology outpatient clinics in a public tertiary centre from July 2017 to October 2018. Clinical data was collected. Screening for hepatic fibrosis was performed using transient elastography (TE), aminoaspartate transaminase to platelet ratio index (APRI), Hepascore and Fibrosis-4 index (FIB-4). Those with suspected significant liver fibrosis based on these screening tests were assessed by a hepatologist. RESULTS: Twenty-seven patients were suspected to have liver fibrosis on screening, including 10/56 (18%) by TE, 20/56 (36%) by Hepascore, 2/56 by APRI (4%) and 1/56 by FIB-4 (2%). Of these 27 patients, 11 were reviewed by a hepatologist and one diagnosed with significant liver fibrosis. TE, but not APRI, Hepascore or FIB-4, was found to have 100% sensitivity and 84% specificity (P = 0.029) for hepatologist-diagnosed liver fibrosis. CONCLUSION: Liver fibrosis develops in a minority of MTX-treated RA patients. The present study suggests that TE is a more sensitive screening test than APRI, FIB-4 or Hepascore in the identification of people with RA at risk of hepatic fibrosis.

The bronchiolitis season is upon us--recommendations for the management and prevention of acute viral bronchiolitis.

Despite being so common, bronchiolitis remains poorly diagnosed and managed. This article is intended as an update on issues pertaining to this condition.