Journal of medical microbiology
-
Paediatric acute gastroenteritis is a global public health problem. Comprehensive laboratory investigation for viral, bacterial and parasitic agents is helpful for improving management of acute gastroenteritis in health care settings and for monitoring and controlling the spread of these infections. Our study aimed to investigate the role of various pathogens in infantile diarrhoea in Bulgaria outside the classical winter epidemics of rotavirus and norovirus. ⋯ Rotavirus predominant genotypes were G4P[8] (46.3 %) and G2P[4] (21.4 %); for astroviruses, type 1a was the most common, while the GII.4/2006b variant was the most prevalent among noroviruses. Bacteria were observed in five cases, with Salmonella sp. as the most prevalent, while parasites were found in ten stool samples, with Giardia intestinalis in five cases. The results demonstrated high morbidity associated with viral infections and that rotavirus and norovirus remain the most common pathogens associated with severe gastroenteritis during summer months in Bulgaria, a country with a temperate climate, and significant molecular diversity among circulating virus strains.
-
Nontuberculous mycobacteria (NTM) causing human infectious disease have become increasingly common. Rapid and accurate identification to the species level is, therefore, critical. The Speed-Oligo Mycobacteria assay is an oligochromatographic method that was made available recently for the identification and differentiation of mycobacteria. ⋯ For these strains, sequencing of the genes hsp65, 16S rRNA and rpoB and the GenoType Mycobacterium CM assay were performed. The Speed-Oligo Mycobacteria assay can be a useful tool for the rapid and easy identification of the most common NTM. If applied in clinical practice it could reduce diagnostic delays and contribute to correct clinical and better management of infections caused by NTM.
-
The purpose of this study was to evaluate the risk factors, outcomes and epidemiology associated with Clostridium difficile infection (CDI) in patients with haematological malignancies in a tertiary care hospital in China. C. difficile screening was performed on patients admitted for chemotherapy or haematopoietic stem cell transplantation between 2009 and 2013. C. difficile isolates were analysed by multilocus sequence typing, and a retrospective chart review was performed on all patients with a positive toxin assay. ⋯ Ten sequence types (STs) were identified, of which ST-3 and ST-54 were the most common; the hypervirulent ST-1 (ribotype 027) and ST-11 (ribotype 078) C. difficile strains were not detected in the patients in this study. The incidence of CDI did not differ between patients receiving chemotherapy and those receiving haematopoietic stem cell transplantation. The only risk factor for chemotherapy patients was treatment with etoposide.
-
This study evaluated the predictors of mortality and the impact of inappropriate therapy on the outcomes of patients with bacteraemia and ventilator-associated pneumonia (VAP). Additionally, we evaluated the correlation of the type III secretion system (TTSS) effector genotype with resistance to carbapenems and fluoroquinolones, mutations in the quinolone resistance-determining regions (QRDRs), metallo-β-lactamase and virulence factors. A retrospective cohort was conducted at a tertiary hospital in patients with multidrug-resistant (MDR) P. aeruginosa bacteraemia (157 patients) and VAP (60 patients). ⋯ Substitution of threonine to isoleucine at position 83 in gyrA was the most frequent mutation among fluoroquinolone-resistant strains. Our study showed a mutation at position 91 in the parC gene (Glu91Lys) associated with a mutation in gyrA (Thre83Ile) in a strain of extensively drug-resistant P. aeruginosa, with the exoT(+)exoS(+)exoU(+) genotype, that has not yet been described in Brazil to the best of our knowledge. This comprehensive analysis of resistance mechanisms to carbapenem and fluoroquinolones and their association with TTSS virulence genes, covering MDR P. aeruginosa in Brazil, is the largest reported to date.
-
This study aimed to assess the molecular basis of the resistance to carbapenems in clinical isolates of Pseudomonas aeruginosa recovered from a tertiary-level health facility in San José, Costa Rica. A total of 198 non-duplicated isolates were evaluated for their susceptibility to β-lactams, aminoglycosides and fluoroquinolones. The production of metallo-β-lactamases (MBLs), the presence of MBL encoding genes (blaIMP, blaVIM and blaGIM-1) and the occurrence of these genes within class 1 integrons were investigated. ⋯ Remarkably, three carbapenem-resistant isolates, exhibiting MBL activity and carrying both blaIMP and blaVIM genes, were recovered from outpatients. Sequence analysis of both bla genes in various isolates revealed that they correspond to the alleles blaIMP-18 and blaVIM-2. To our knowledge, this is the first report of the combination of two metallo-β-lactamases encoded by the blaIMP-18 and blaVIM-2 genes in P. aeruginosa.