Revista Argentina de microbiologia最新文献

Globicatella is a genus of catalase-negative, facultative anaerobes, and non-hemolytic Gram-positive cocci, arranged in pairs or in short chains. Twenty-five positive urine cultures, mainly obtained by catheterization, and two urinary stone cultures due to Globicatella spp. were retrospectively recorded from patients between January 1, 2014 and October 31, 2024. Isolates were identified by mass spectrometry (Vitek MS), 16S rRNA gene sequencing and biochemical tests. Most patients had complex uropathies or congenital malformations of the urinary tract. A high percentage of the isolates showed high ceftriaxone (CRO) MICs (MIC50 and MIC90: 2-16μg/ml) and almost half of them had low penicillin (PEN) MICs (MIC50 and MIC90: 0.25 and 2μg/ml). The present study is the most extensive report of Globicatella urinary tract infections in children.

CMV is one of the main complications associated with transplantation, whether of solid organs or hematopoietic stem cells, and is related to an increase in post-transplant morbidity and mortality. Due to its significant impact, prevention is recommended, either through prophylaxis or other preventive therapies. The latter require viral monitoring of the patient, as viremia serves as a predictor of of the disease, allowing for an early detection and timely preventive treatment. The gold standard for viral monitoring is the quantitative determination of nucleic acids. Laboratories often face practical challenges regarding the type of sample to be used, its transport and storage conditions, the appropriate methods of nucleic acid extraction and quantification, the frequency of monitoring and establishment of cut-off points to ensure the accuracy and reproducibility of CMV viral load test results. The Argentine Society of Virology has formed a working group specifically dedicated to addressing these difficulties. This document aims to provide recommendations on the aforementioned points based on the available scientific evidence and the expertise of the working group.

Neutropenia has been recognized for many decades as the most important determinant of infection risk in cancer patients. The aim of this study is to describe the clinical and demographic characteristics, type of microbiological isolates, and resistance to antimicrobials of patients with hemato-oncological neoplasms who experienced febrile neutropenia as a complication in a third-level clinic in the city of Cali. A single-center retrospective descriptive study was conducted. Data were retrieved from the medical records of cancer patients who developed post-chemotherapy febrile neutropenia between January 2014 and December 2021. Ninety-six patients were included in the study. An infectious focus was documented in 41% of the cases, with more than one microbiological isolate identified in 2.5%. Gram-negative bacilli predominated, and were isolated in 84.6% of cases. Regarding resistance mechanisms determined phenotypically in E. coli and Klebsiella pneumoniae, ESBL resistance was found in 28.6% and 30% of cases, respectively, and KPC-type carbapenemases in 2.6% of the isolates. Infection-associated mortality was 9.3%. The infectious focus is likely to go undocumented In patients with febrile neutropenia, and infection-associated mortality is low.

Globalization and the introduction of exotic pets have led to the identification of new species that produce tinea in humans. Here, we report the clinical case of a 22-year-old female, who presented with a lesion on her hand that was compatible with dermatophytosis. Molecular biology methods identified the cultured fungus as Trichophyton erinacei.

Salmonella genus includes around 2600 serovars, causing important zoonotic diseases and enteric fever, with significant impact on public health worldwide. Serovar characterization is commonly achieved by phenotypic and genotypic tests, requiring several days to obtain a result. Mass spectrometry (MS) only allows identification of Salmonella isolates at the genus level. Our aim was to evaluate the performance of MS for Salmonella ser. Enteritidis (SE), Salmonella ser. Typhimurium (STM)/4,[5],12:i:- and Salmonella ser. Typhi (ST) specific-serovar biomarker detection. We included 257 isolates from 34 different serovars (62 SE, 69 STM/4,[5],12:i:-, 17 ST) for analysis of spectra obtained by the direct method, using CHCA as matrix. For acquisition, we used Biotyper MicroFlex LT (Bruker Daltonics) and VITEK MS PRIME (BioMérieux) platforms, and performed a manual search for previously described biomarkers. Using Biotyper MicroFlex LT, sensitivity (Se) for the 3016Da and 6036Da SE biomarkers was 85% and 95%, respectively (specificity (Sp)=100%). The Se for the STM/4,[5],12:i:- biomarker (7095Da) was 100% and the Sp=98%. For ST biomarker (5710Da), Se and Sp were 88% and 100%, respectively. For VITEK MS PRIME, Se for the 3018Da SE biomarker was 42% and for the 6036Da was 79% (Sp=100% for both); for the STM/4,[5],12:i:- biomarker (7096Da), Se was 83% and Sp=97%; and for the ST biomarker (5712Da), Se=94% and Sp=100%. The identification of these frequent serovars can be expedited using MALDI-TOF MS technology. The rapid and reliable diagnosis of salmonellosis can have a positive impact on patient outcomes and public health.

The poultry industry represents an important economic sector in Argentina. In this study we recovered 26 vancomycin-resistant Enterococcus (VRE) isolates from different productive stages of a poultry farm located in Tandil, Argentina. Ten isolates were Enterococcus faecium and seven, Enterococcus faecalis. Total resistance to vancomycin (96.2%), erythromycin (80.8%), levofloxacin (57.7%), chloramphenicol (26.7%), penicillin (23.1%), ampicillin (7.7%) was detected and 20 isolates (76.9%) were identified as multidrug-resistant (MDR). With respect to the distribution of glycopeptide resistance genes, 57.7% of the isolates harbored the vanC-1 gene, and 11.5%, carried the vanC-2/C-3 gene. The vanA and vanB variants were not detected. This study provides evidence that healthy chickens from the studied region can be a reservoir of MDR-VRE. Further surveillance should be conducted to control their dissemination through the food chain.

Standardized doses such as defined daily doses (DDDvet) and defined course doses (DCDvet) are essential to quantify the antimicrobials (AMs) used in veterinary medicine as a prior step for determining strategies for their responsible use. Therefore, the aim of this study was to create a list of the available intramammary formulations for mastitis and drying off in Argentina, and to estimate their DDDvet and DCDvet. DDDvet and DCDvet were determined for 29 mastitis cases and 27 drying formulations. Critically important AM formulations of the highest priority for human health (ceftiofur or cefquinome) were identified. In addition, there were combined formulations with up to four different AMs, including critically important AMs. The results of this study show a high diversity of formulations and concentrations, low availability of mono-drug products, and a high proportion of combinations that include AMs considered essential for human health. These findings highlight the urgent need to standardize dosages in Argentina, prioritize the use of AMs of low medical importance, and promote the prudent and rational use of these drugs, in line with a One Health approach.

Among the pathogenic fungi of strawberry (Fragaria ananassa Duch.), Botrytis cinerea, a filamentous necrotrophic fungus that causes gray mold, stands out worldwide for its ubiquity and prevalence. Chemical control has been the most effective method used for years to manage B. cinerea in strawberry crops. However, the frequent use of numerous fungicides has increased issues related to pathogen resistance, resurgence, and toxic residues. In this study, we propose the use of the plant growth-promoting bacterium Azospirillum argentinense REC3 and its flagellin AzFlap, whether non-glycosylated or glycosylated, for the control of B. cinerea. We observed that only REC3 inhibited the mycelial growth of B. cinereain vitro, whereas AzFlap had no inhibitory effect. Moreover, REC3 and only its glycosylated flagellin AzFlap contributed to reducing lesions caused by B. cinerea on detached strawberry leaves.

The spontaneous coffee fermentation process can be regulated through the application of microbial starter cultures, which are used to enhance the quality of the coffee. In this study, microorganisms derived from coffee fermentations conducted on a representative farm in Southwestern Colombia, where specialty export-type coffee is produced, were isolated, characterized, and identified. The methodology used was based on cultivation techniques of key microbial groups in coffee fermentation, which enabled to establish a collection of microorganisms with future applications in postharvest coffee processing. The microorganisms that exhibited significant characteristics within the established criteria of this study, which were used for the selection of starter cultures for coffee fermentation, belonged to microbial genera or species that are commonly found during the coffee fermentation process. Consequently, the strains Acetobacter tropicalis m108, Kosakonia cowanii P121, Leuconostoc mesenteroides M154, L. mesenteroides M159, Lactiplantibacillus plantarum M157, Pichia kluyveri Y144, P. kudriavzevii Y150, Wickerhamomyces anomalus Y149, and Rhodotorula mucilaginosa Y147 were selected for further study. These strains represent a valuable genetic resource that could contribute to enhancing the quality of coffee from the region, particularly in regard to its cup quality, for future use as starter cultures.