Roberto Alonso

Dr. Roberto Alonso

orcid

Research Focus & Metrics

Academic Career Length

25Years (2002-Present)

(Calculated once Scilit publication data is synced: current year − year of first publication + 1)

Representative Publications

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16 March 2022 in Journal of Fungi
Verified
Journal Article
Open access
PDF file
MMMarina Machado
Marina Machado
AEAGUSTIN ESTEVEZ
AGUSTIN ESTEVEZ
CSCarlos Sánchez-Carrillo
Carlos Sánchez-Carrillo
Jesus GuineaJesus Guinea
Jesus Guinea
Pilar EscribanoPilar Escribano
Pilar Escribano
PMPatricia Munoz
Patricia Munoz
There is scarce information on the actual incidence of candidemia in COVID-19 patients. In addition, comparative studies of candidemia episodes in COVID-19 and non-COVID-19 patients are heterogeneous. Here, we assessed the real incidence, epidemiology, and etiology of candidemia in COVID-19 patients, and compared them with those without COVID-19 (2020 vs. 2019 and 2020, respectively). We also genotyped all C. albicans, C. parapsilosis, and C. tropicalis isolates (n = 88), causing candidemia in both groups, providing for the first time a genotypic characterization of isolates gathered in patients with either COVID-19 or non-COVID-19. Incidence of candidemia was higher in patients with COVID-19 than non-COVID-19 (4.73 vs. 0.85 per 1000 admissions; 3.22 vs. 1.14 per 10,000 days of stay). No substantial intergroup differences were found, including mortality. Genotyping proved the presence of a low number of patients involved in clusters, allowing us to rule out rampant patient-to-patient Candida transmission. The four patients, involved in two clusters, had catheter-related candidemia diagnosed in the first COVID-19 wave, which demonstrates breaches in catheter management policies occurring in such an overwhelming situation. In conclusion, the incidence of candidemia in patients with COVID-19 is significantly higher than in those without COVID-19. However, genotyping shows that this increase is not due to uncontrolled intrahospital transmission.

27 April 2022 in Microbiology Spectrum
Verified
Journal Article
Open access
ACAlba Leyva Calero
Alba Leyva Calero
RARoberto Alonso
Roberto Alonso
IGIgnacio Gadea
Ignacio Gadea
MVMaría Dolores Montero Vega
María Dolores Montero Vega
MGMarta Martín García
Marta Martín García
JGJulio García-Rodríguez
Julio García-Rodríguez
Invasive mycoses are increasingly present in immunosuppressed or hospitalized patients with serious illnesses, leading to high rates of morbidity and mortality. Invasive aspergillosis is an infection caused, in a percentage greater than 50%, by the genus Aspergillus .

1 March 2018 in Enfermedades Infecciosas y Microbiología Clínica
Verified
Journal Article
Closed access
RARoberto Alonso
Roberto Alonso
FPFelipe Pérez-García
Felipe Pérez-García
PLPaula López-Roa
Paula López-Roa
LALuis Alcalá
Luis Alcalá
PRPilar Rodeño
Pilar Rodeño
EBEmilio Bouza
Emilio Bouza

1 May 2002 in Antimicrobial Agents and Chemotherapy
Verified
Journal Article
Open access
PDF file
TPT. Peláez
T. Peláez
RARoberto Alonso
Roberto Alonso
CPC. Pérez
C. Pérez
LAL. Alcalá
L. Alcalá
OCO. Cuevas
O. Cuevas
EBE. Bouza
E. Bouza
We examined the in vitro activity of linezolid against Clostridium difficile, including isolates with reduced susceptibility to metronidazole or vancomycin. The MIC at which 50% of the isolates were inhibited (MIC 50 ) and MIC 90 were 0.5 and 2 μg/ml, respectively (range, 0.03 to 4 μg/ml). MICs were always ≤ 4 μg/ml, and thus, all isolates were considered susceptible.

28 March 2023 in Journal of Fungi
Verified
Journal Article
Open access
PDF file
CVCristina Veintimilla
Cristina Veintimilla
AUAna Álvarez Uría
Ana Álvarez Uría
PMPablo Martín-Rabadán
Pablo Martín-Rabadán
MVMaricela Valerio
Maricela Valerio
MMMarina Machado
Marina Machado
MAMercedes Marin Arriaza
Mercedes Marin Arriaza
Pneumocystis jirovecii pneumonia (PJP) in immunocompromised patients entails high mortality and requires adequate laboratory diagnosis. We compared the performance of a real time-PCR assay against the immunofluorescence assay (IFA) in the routine of a large microbiology laboratory. Different respiratory samples from HIV and non-HIV-infected patients were included. The retrospective analysis used data from September 2015 to April 2018, which included all samples for which a P. jirovecii test was requested. A total of 299 respiratory samples were tested (bronchoalveolar lavage fluid (n = 181), tracheal aspirate (n = 53) and sputum (n = 65)). Forty-eight (16.1%) patients fulfilled the criteria for PJP. Five positive samples (10%) had only colonization. The PCR test was found to have a sensitivity, specificity, positive predictive value (PPV) and negative predictive value (NPV) of 96%, 98%, 90% and 99%, compared to 27%, 100%, 100% and 87%, for the IFA, respectively. PJ-PCR sensitivity and specificity were >80% and >90% for all tested respiratory samples. Median cycle threshold values in definite PJP cases were 30 versus 37 in colonized cases (p < 0.05). Thus, the PCR assay is a robust and reliable test for the diagnosis PJP in all respiratory sample types. Ct values of ≥36 could help to exclude PJP diagnosis.

1 November 2019 in Journal of Hepatology
Verified
Journal Article
Closed access
APAna Belén Pérez
Ana Belén Pérez
NCNatalia Chueca
Natalia Chueca
MGMiguel García-Deltoro
Miguel García-Deltoro
AMAna María Martínez-Sapiña
Ana María Martínez-Sapiña
MLMaría Magdalena Lara-Pérez
María Magdalena Lara-Pérez
CGConcepción Grau
Concepción Grau