Clinical Performance Evaluation of a Rapid Real-Time PCR Assay for Monkeypox Diagnosis: a Retrospective and Comparative Study.

In an increasingly globalized and interconnected world, the outbreak of an infectious disease in one country can become a worrying health emergency for the whole world. A current example is the 2022 monkeypox virus (mpox) outbreak affecting multiple areas across the world. In this context, strategies to interrupt transmission as soon as possible by identifying cases, clusters, and sources of infection should be developed around the world to prevent these crises. The aim of this retrospective and collaborative study was to perform external clinical validation of the VIASURE monkeypox virus real-time PCR detection kit (CerTest Biotec, Spain) with ready-to-use reagents designed for the rapid detection of mpox. A total of 165 samples with suspected infection were used for this analysis. The standard procedures of the clinical microbiology laboratory of the Miguel Servet University Hospital, using the RealStar Orthopoxvirus PCR kit v1.0 (Altona Diagnostics) and bidirectional Sanger sequencing (STAB VIDA, Caparica, Portugal), were considered reference techniques. Furthermore, a subset of 67 mpox-negative samples and 13 mpox-positive samples were routinely tested for clinical diagnosis of other rash/ulcerative pathologies. Accuracy testing resulted in appropriate clinical validation values, as follows: sensitivity, 1 (95% confidence interval [CI], 0.97 to 1); specificity, 1 (95% CI, 0.98 to 1); positive predictive value, 1 (95% CI, 0.93 to 1); negative predictive value, 1 (95% CI, 0.95 to 1). The strength of agreement between assays was almost perfect. The added value is the useful support for the specific diagnosis of mpox infections due to the diagnostic specificity data obtained. IMPORTANCE Given that a large number of mpox outbreaks have been reported worldwide since 2022 in countries in which the disease is not endemic, the main concern for clinicians and global health systems should be to develop effective, available, and easy-to-implement diagnostic strategies to interrupt mpox transmission as soon as possible. This retrospective study demonstrates the satisfactory clinical parameters of a commercially available molecular diagnostic kit for routine testing for mpox in clinical diagnostic laboratories.

Use of MALDI-TOF MS (Bruker Daltonics) for identification of Mycobacterium species isolated directly from liquid medium / Utilización de MALDI-TOF MS (Bruker Daltonics) para la identificación de micobacterias aisladas directamente en medio líquido

Objectives: The aim of this study was to describe the evaluation of the use of MALDI-TOF MS for the identification of non-tuberculous mycobacteria (NTM) and Mycobacterium tuberculosis directly from liquid MGIT cultures from January 2017 to December 2017. Material/methods: A total of 155 isolates (mainly respiratory) were analyzed by MALDI-TOF MS (Bruker Daltonics) directly from MGIT liquid medium with a previous extraction procedure. Results: MALDI-TOF MS generated acceptable scores for 152 isolates (98.06%). Fifty isolates were identified as M. tuberculosis complex and the remaining 105 as NTM (M. abscessus subsp. abscessus, M. avium, M. celatum, M chelonae, M. chimaera, M. fortuitum, M. gordonae, M. intracellulare, M. kansasii, M. lentiflavum, M. mageritense, M. mucogenicum and M. xenopi). Conclusions: These results indicate that MALDI-TOF MS can be useful to identify mycobacteria directly from MGIT cultures and is an accurate, rapid and cost-effective system to be used as a routine method.(AU)

Introducción: Evaluamos la espectrometría de masas (MALDI-TOF MS [Bruker Daltonics]) para la identificación de micobacterias no tuberculosas (MNT) y Mycobacterium tuberculosis a partir de cultivos líquidos (MGIT) desde enero del 2017 a diciembre del 2017. Métodos: Se analizaron mediante MALDI-TOF MS 155 cultivos MGIT positivos, principalmente de origen respiratorio. Previamente a la realización de MALDI-TOF se realizó un procedimiento de extracción directamente del MGIT. Resultados: Mediante MALDI-TOF MS se identificó correctamente a partir del MGIT el 98,06% (n=152) de los aislados. Cincuenta aislados se identificaron como M. tuberculosis complex y los 105 restantes como MNT (M. abscessus subsp. abscessus, M. avium, M. celatum, M chelonae, M. chimaera, M. fortuitum, M. gordonae, M. intracellulare, M. kansasii, M. lentiflavum, M. mageritense, M. mucogenicum y M. xenopi). Conclusiones: Estos resultados indican que MALDI-TOF es una técnica precisa, rápida y coste-efectiva para identificar micobacterias directamente a partir de medios de cultivo líquidos en la rutina diaria.(AU)

Use of MALDI-TOF MS (Bruker Daltonics) for identification of Mycobacterium species isolated directly from liquid medium.

OBJECTIVES: The aim of this study was to describe the evaluation of the use of MALDI-TOF MS for the identification of non-tuberculous mycobacteria (NTM) and Mycobacterium tuberculosis directly from liquid MGIT cultures from January 2017 to December 2017. MATERIAL/METHODS: A total of 155 isolates (mainly respiratory) were analyzed by MALDI-TOF MS (Bruker Daltonics) directly from MGIT liquid medium with a previous extraction procedure. RESULTS: MALDI-TOF MS generated acceptable scores for 152 isolates (98.06%). Fifty isolates were identified as M. tuberculosis complex and the remaining 105 as NTM (M. abscessus subsp. abscessus, M. avium, M. celatum, M chelonae, M. chimaera, M. fortuitum, M. gordonae, M. intracellulare, M. kansasii, M. lentiflavum, M. mageritense, M. mucogenicum and M. xenopi). CONCLUSIONS: These results indicate that MALDI-TOF MS can be useful to identify mycobacteria directly from MGIT cultures and is an accurate, rapid and cost-effective system to be used as a routine method.

Nasal carriage of coagulase positive staphylococci in patients of a Primary-Healthcare-Center: genetic lineages and resistance and virulence genes.

INTRODUCTION: Staphylococcus aureus and Staphylococcus pseudintermedius are highly important due to their capacity for producing diseases in humans and animals, respectively. The aim of the study was to investigate and characterize the coagulase positive Staphylococcus (CoPS) carriage in a Primary Healthcare Center population. METHODS: Nasal swabs were obtained from 281 non-infectious patients. The CoPS isolates recovered were typed, and their resistance phenotype and genotype, as well as their virulence profiles, were analyzed. RESULTS: CoPS isolates were recovered from 56/281 patients (19.9%). Fifty-five were S. aureus (19.6%), 54 were methicillin susceptible (MSSA) and one was methicillin resistant (MRSA). The remaining isolate was S. pseudintermedius (0.4%). A high diversity of spa-types (n=40) was detected, with 6 of them being new ones. The multi-locus-sequence-typing of 13 MSSA and one MRSA selected isolates was performed and the STs detected were: ST8, ST15, ST30, ST34, ST121, ST146, ST398, ST554, ST942, ST2499, and ST2500 (the last two STs being new). One MSSA isolate was typed as t1197-ST398-(Clonal complex)CC398. The MRSA isolate was typed as t002-ST146-CC5-SCCmec-IVc, and exhibited a multiresistance phenotype. The detected resistances were: penicillin (76%), macrolides (7%), tetracycline (7%), trimethoprim-sulfamethoxazole (7%), quinolones (7%), and lincosamides (5%). Five isolates contained lukF/lukS-PV genes, 17 tst gene, one eta gene, and two etb gene. The S. pseudintermedius isolate presented a new spa-type (t57) (belonging to a new ST180) and the genes lukS/F-I, siet, se-int, and expB. CONCLUSIONS: A high genetic diversity of S. aureus was detected. Mention must be made of the identification of MSSA CC398 and S. pseudintermedius isolates in two patients, one of them with animal contact. The detection of the genes lukF/lukS-PV and tst should be noted.

Cutaneous sporotrichosis treated with photodynamic therapy: an in vitro and in vivo study.

BACKGROUND: Sporotrichosis is a fungal infection caused by Sporothrix schenckii complex, usually restricted to the skin, subcutaneous cellular tissue, and adjacent lymphatic vessels. Antimicrobial photodynamic therapy (aPDT) could be a good alternative to manage localized, superficial infections. CASE REPORT: A 65-year-old African woman was diagnosed with a fixed cutaneous sporotrichosis on her left arm, treated with itraconazol and oral terbinafine with partial improvement. Topical 16% methyl aminolevulinate (MAL, Metvix(®))-PDT was used without success. METHODS: An in vitro photoinactivation test with the isolated microorganism revealed phenothiazinium salts to be more effective than MAL. CONCLUSIONS: PDT with intralesional 1% methylene blue (MB) in combination with intermittent low doses of itraconazole obtained complete microbiological and clinical response.

Caracterización de cepas de Staphylococcus epidermidis y S. haemolyticus resistentes a meticilina y linezolid en un hospital español / Characterization of methicillin- and linezolid-resistant Staphylococcus epidermidis and S. haemolyticus strains in a Spanish hospital

La resistencia a linezolid se produce generalmente por mutaciones en el ARNr 23S. El objetivo de este estudio fue caracterizar cepas de Staphylococcus epidermidis (SE) y S. haemolyticus (SH) resistentes a linezolid y meticilina (SE-LMR y SH-LMR, respectivamente) detectadas en un hospital español. Métodos Se estudiaron todas las cepas SE-LMR y SH-LMR aisladas en el periodo de junio 2009 a agosto 2011, en un hospital de segundo nivel, así como las características epidemiológicas de los pacientes. Se tiparon las cepas (25 SE-LMR y 2 SH-LMR, procedentes de 20 pacientes) y se determinó su fenotipo y genotipo de resistencia y la presencia de genes de virulencia. Resultados En todas las cepas analizadas se detectó la mutación G2603T en el ARNr 23S y también cambios aminoacídicos en las proteínas ribosomales L3 y L4. Las 25 cepas SE-LMR pertenecieron a la secuencia tipo ST2, su SCCmec fue el tipo III y presentaron 2 patrones diferentes de PFGE. El SCCmec de las 2 cepas SH-LMR fue no tipable. Las cepas SE-LMR contenían los genes de resistencia aac(6’)-aph(2”) y dfrS1, y las cepas SH-LMR poseían además el gen erm(C). No se detectaron genes de resistencia a lincomicina en las cepas SE-LMR a pesar de mostrar sensibilidad disminuida a clindamicina y resistencia a lincomicina. Conclusiones La resistencia a linezolid en el ámbito hospitalario es preocupante y requiere una continua vigilancia. Esta resistencia se asoció a la mutación G2603T en el ARNr 23S y a la presencia de cambios aminoacídicos en L3 y/o L4 (AU)

Introduction Linezolid resistance is mainly due to mutations in the 23S rRNA target. The aim of this study was to characterize linezolid and methicillin resistant Staphylococcus epidermidis (SE-LMR) and S. haemolyticus (SH-LMR) strains detected in a Spanish hospital. Methods SE-LMR and SH-LMR strains obtained in the period June 2009-August 2011 in a second level hospital were recorded along with the epidemiological characteristics of the patients. These strains were typed, and their resistance, phenotype, genotype and the factors determining their virulence were analysed. Results Linezolid resistance was explained by the presence of G2603T mutation (23S rRNA) and aminoacid changes in L3 and L4 ribosomal proteins. The 25 SE-LMR strains belonged to sequence type ST2, presented SCCmec type III, and two different PFGE patterns. The two SH-LMR strains showed non-typeable SCCmec. SE-LMR strains harboured the resistance genes aac(6’)-aph(2”), and dfrS1. SH-LMR strains contained these genes and the gene erm(C). No lincomycin resistance mechanism was identified in SE-LMR strains regardless of showing lincomycin resistance and diminished susceptibility to clindamycin. Conclusions Linezolid resistance is of concern in hospitals, and requires continued vigilance. Several linezolid resistance mechanisms (mutation in 23S RNAr and amino acid changes in L3 and L4) were identified in this study (AU)

[Characterization of methicillin- and linezolid-resistant Staphylococcus epidermidis and S. haemolyticus strains in a Spanish hospital]. / Caracterización de cepas de Staphylococcus epidermidis y S. haemolyticus resistentes a meticilina y linezolid en un hospital español.

INTRODUCTION: Linezolid resistance is mainly due to mutations in the 23S rRNA target. The aim of this study was to characterize linezolid and methicillin resistant Staphylococcus epidermidis (SE-LM(R)) and S. haemolyticus (SH-LM(R)) strains detected in a Spanish hospital. METHODS: SE-LM(R) and SH-LM(R) strains obtained in the period June 2009-August 2011 in a second level hospital were recorded along with the epidemiological characteristics of the patients. These strains were typed, and their resistance, phenotype, genotype and the factors determining their virulence were analysed. RESULTS: Linezolid resistance was explained by the presence of G2603T mutation (23S rRNA) and aminoacid changes in L3 and L4 ribosomal proteins. The 25 SE-LM(R) strains belonged to sequence type ST2, presented SCCmec typeIII, and two different PFGE patterns. The two SH-LM(R) strains showed non-typeable SCCmec. SE-LM(R) strains harboured the resistance genes aac(6')-aph(2"), and dfrS1. SH-LM(R) strains contained these genes and the gene erm(C). No lincomycin resistance mechanism was identified in SE-LM(R) strains regardless of showing lincomycin resistance and diminished susceptibility to clindamycin. CONCLUSIONS: Linezolid resistance is of concern in hospitals, and requires continued vigilance. Several linezolid resistance mechanisms (mutation in 23S RNAr and amino acid changes in L3 and L4) were identified in this study.