Aims We describe the presence of Helicobacter pylori (HP) and estimated the prevalence of primary and secondary resistance using molecular detection in gastric biopsies of Ecuadorian patients. Methods and Results A 66.7% (238/357) of the patients demonstrated the presence of HP using CerTest qPCR. Of these 69.79% (104/149) without previous HP eradication treatment and 64.42% (134/208) with prior HP eradication treatment. The mutation-associated resistance rate for clarithromycin was 33.64% (Primary resistance) and 32.82% (Secondary resistance). While that in levofloxacin the primary and secondary resistance was 37.38% and 42%, respectively. For tetracycline and rifabutin, primary and secondary resistance was 0%. Primary and secondary resistance for metronidazole and amoxicillin could not be evaluated by genotypic methods (PCR and sequencing). Conclusions The analysis of mutations in gyrA, 23S rRNA, and 16S rRNA is useful is useful to detect bacterial resistance as a guide for eradication therapy following failure of the first-line regimen. Significance and Impact of Study This study carried out in an Ecuadorian population indicates that the resistance of HP to first-line antibiotics is high, which may contribute to the high rates of treatment failure, and other treatment alternatives should be considered.

Candida parapsilosis complex includes Candida parapsilosis sensu stricto, Candida orthopsilosis, Candida metapsilosis, which are phenotypically indistinguishable from each other. They show differences in virulence, susceptibility to antifungals and epidemiology. This study aimed to evaluate the phylogenetic analysis using ITS gene sequences from clinical isolates, collected between 2018 to 2023, as a new diagnostic tool for the identification of these species. A total of 84 yeasts were studied from patients between 0 and 96 years old. Male patients were the most affected. They were isolated most frequently from blood, ear secretions, skin, and soft tissues. Candidemia was an important clinical entity in children under 1 year of age and in the group of adults from 20 to 65 years of age. Through phylogenetic analysis, C. parapsilosis sensu stricto was identified in 74 isolates, C. orthopsilosis in 7 isolates and 3 C. metapsilosis in 3 isolates. The use of phylogenetic trees as a diagnostic tool allowed to distinguish the members of the Candida parapsilosis complex, by analyzing similarities between the sequences of the ITS region. For the management of the infection caused by these species the appropriate identification is required. El complejo Candida parapsilosis está compuesto por Candida parapsilosis sensu estricto, Candida ortopsilosis, Candida metapsilosis, que son fenotípicamente indistinguibles entre sí. Presentan diferencias en virulencia, susceptibilidad a antifúngicos y epidemiología. Este estudio tuvo como objetivo evaluar el análisis filogenético utilizando secuencias del gen ITS de aislados clínicos, recolectados entre 2018 al 2023, como una nueva herramienta diagnóstica para la identificación de estas especies. Un total de 84 levaduras fueron descongeladas de pacientes entre 0 a 96 años. Los pacientes de sexo masculino fueron los más afectados. Se aislaron con mayor frecuencia de sangre, secreciones óticas, piel anexos y tejidos blandos y secreciones óticas. La candidemia fue una entidad clínica importante en menores de 1 año y en el grupo de adultos de 20 a 65 años. Mediante el análisis filogenético se llegó a la identificación C. parapsilosis sensu estricto en 74 aislamientos, C. orthopsilosis en 7 aislamientos y 3 C. metapsilosis en 3 aislamientos. El uso de árboles filogenéticos como herramienta diagnóstica nos permitió distinguir los miembros del complejo Candida parapsilosis, mediante el análisis de similitudes entre las secuencias de la región ITS. Se plantea la necesidad de la identificación de estas tres especies para el manejo clínico y epidemiológico.

Over the last years, several studies on bloodstream infections (BSI) have ranked P. aeruginosa in the top 5 list of Gram-negative causal agents. However, there is very limited data regarding the incidence of Pseudomonas bacteremia in Latin America. The aim of this study was to establish the incidence of bacteremia caused by Pseudomonas species During the period from November 2021 to May 2022 in 9 hospitals in Ecuador, blood culture samples were taken according to the clinical requirements of each patient. The bacteria identification was carried out using automated system (Vitek2 and Phoenix1000) and was confirmed by proteomic (MALDITOF) and molecular sequencing. Antimicrobial susceptibility was performed according to CLSI 2021. This study provided relevant information on BSI caused by Pseudomonas in Ecuador.There are only few population-based studies evaluating bacteremia epidemiology in Latin America. SENTRY in 1997 estimated that P. aeruginosa contributed to 10.6% of gram-negative nosocomial and community-acquired bloodstream infections. Lower incidence levels, as seen in this study (0.043%), could help better understand population trends and help guide treatment. Jeannete Zurita, n/a, Pfizer: Grant/Research Support

Due to the differential treatment required by non-tuberculous mycobacteria (NTM) infections, accurate identification in clinical isolates is necessary for correct management, effective treatment, and appropriate control strategies. Traditional methods, including phenotypic tests, are slow, cumbersome, and often not definitive. PCR-based methods, such as restriction fragment length polymorphism analysis, are still very time-consuming and sometimes lead to inaccurate identification because they handle fragments of different sequences but do not agree with their evolutionary origin. Sequencing is the most accurate method for species identification, with the 16S rRNA, hsp65, and rpoB genes being considered as candidates for phylogenetic and diagnostic studies. In this study, we developed a phylogenetic analysis using the 16S rRNA, hsp65, and rpoB gene sequences of Mycobacterium clinical isolates, collected between 2018 and 2022, for taxonomic categorization of Mycobacterium species, and evaluated their use for Mycobacterium species identification of clinical interest. In addition, we analyzed the genotype-phenotype correlation using characteristics such as sample origin, growth rate, and antimicrobial resistance. An alignment matrix was built (MacVector 18.5.8) based on the sequences generated in this study and sequences retrieved from NCBI, and phylogenetic analyses were performed using PAUP 4.0a. The rpoB and hsp65 markers showed phylogenetic information at the level of groups of species and subspecies, while the 16S rRNA gene was shown to be the most conserved gene, yielding a structure at the level of species complexes that can be used as a first level of identification. The clinical isolates showed phylogenetic homology with the M. abscessus, M. avium, M. fortuitum, and M. intracellulare groups. The synapomorphic characters varied between genes analyzed, showing a correlation between genotype and phenotype useful for evolutionary trends, natural classification, and molecular identification methods for clinical and treatment purposes. Keywords: taxonomy; mycobacterial classification; phylogenetics; homology; clinical isolates; molecular identification; genotypic-phenotypic correlation.