Isaac Peña-Tuesta

Dr. Isaac Peña-Tuesta

orcid

Research Focus & Metrics

Academic Career Length

8Years (2019-Present)

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

Representative Publications

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10 February 2020 in BMC Research Notes
Verified
Journal Article
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JLJohanna Martins Luna
Johanna Martins Luna
LVLuis J. del Valle
Luis J. del Valle
WCWilmer Gianfranco Silva Caso
Wilmer Gianfranco Silva Caso
ISIsabel Sandoval
Isabel Sandoval
LVLuis J. del Valle
Luis J. del Valle
MLMiguel Angel Aguilar Luis
Miguel Angel Aguilar Luis
Objective: To evaluate the frequency of infection caused by the Oropouche virus (OROV) in 496 patients with acute febrile disease (AFI), whose samples were obtained for the analysis of endemic arboviruses in a previous investigation carried out in 2016. Results: OROV was detected in 26.4% (131/496) of serum samples from patients with AFI. Co-infections with Dengue virus (7.3%), Zika virus (1.8%) and Chikungunya (0.2%) were observed. The most common clinical symptoms reported among the patients with OROV infections were headache 85.5% (112/131), myalgia 80.9% (106/131), arthralgia 72.5% (95/131) and loss of appetite 67.9% (89/131). Headache and myalgia were predominant in all age groups. Both OROV infections and co-infections were more frequent in May, June and July corresponding to the dry season of the region.

29 May 2021 in BMC Research Notes
Verified
Journal Article
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LVLuis J. del Valle
Luis J. del Valle
CPCarlos Palomares-Reyes
Carlos Palomares-Reyes
HCHugo Carrillo-Ng
Hugo Carrillo-Ng
YTYordi Tarazona-Castro
Yordi Tarazona-Castro
SKSungmin Kym
Sungmin Kym
WCWilmer Gianfranco Silva Caso
Wilmer Gianfranco Silva Caso
Objective: This study was carried out to determine the prevalence of leptospirosis among febrile patients with a suspicious clinical diagnosis of dengue fever in northern Peru. Results: A total of 276 serum samples from patients with acute febrile illness (AFI) and suspected diagnosis for dengue virus (DENV) were analyzed. We identified an etiological agent in 121 (47.5%) patients, DENV was detected in 30.4% of the cases, leptospirosis in 11.2% and co-infection by both pathogens was observed in 5.9% of the patients. In this study the most common clinical symptoms reported by the patients were: headache 89.1%, myalgias 86.9% and arthralgias 82.9%. No differences in symptomatology was observed among the different study groups.

21 January 2021 in BMC Research Notes
Verified
Journal Article
Open access
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MLMiguel Angel Aguilar Luis
Miguel Angel Aguilar Luis
LVLuis J. del Valle
Luis J. del Valle
ISIsabel Sandoval
Isabel Sandoval
WCWilmer Gianfranco Silva Caso
Wilmer Gianfranco Silva Caso
FMFernando Mazulis
Fernando Mazulis
LVLuis J. del Valle
Luis J. del Valle
Objective: To describe frequency and clinical characteristics of MAYV infection in Piura, as well as the association of this pathogen with DENV.Results: A total of 86/496 (17.3%) cases of MAYV were detected, of which 54 were MAYV mono-infection and 32 were co-infection with DENV, accounting for 10.9% and 6.4%, respectively. When evaluating monoinfection by MAYV the main groups were 18–39 and 40–59 years old, with 25.9% and 20.4% respectively. Co-infections were more common in the age group 18–39 and those > 60 years old, with 34.4% and 21.9%, respectively. The most frequent clinical presentation were headaches (94.4%, 51/54) followed by arthralgias (77.8%, 42/54). During the 8-month study period the most cases were identified in the months of May (29.1%) and June (50.0%).

28 January 2022 in BMC Infectious Diseases
Verified
Journal Article
Open access
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LVLuis J. del Valle
Luis J. del Valle
YTYordi Tarazona-Castro
Yordi Tarazona-Castro
ALAndrés Alfredo Merino Luna
Andrés Alfredo Merino Luna
HCHugo Carrillo-Ng
Hugo Carrillo-Ng
SKSungmin Kym
Sungmin Kym
WCWilmer Gianfranco Silva Caso
Wilmer Gianfranco Silva Caso
Background: At the end of 2019, a novel coronavirus denominated SARS-CoV-2 rapidly spread through the world causing the pandemic coronavirus disease known as COVID-19. The difference in the inflammatory response against SARS-CoV-2 infection among people living at different altitudes is a variable not yet studied.Methods: A descriptive cross-sectional study was performed in two Peruvian cities at different altitudes for comparison: Lima and Huaraz. Five important proinflammatory cytokines were measured including: IL-6, IL-2, IL-10, IFN-γand TNF-α using ELISA assays.Results: A total of 35 COVID-19 patients and 10 healthy subjects were recruited from each study site. The mean levels of IL-6 (p < 0.03) and TNF-α (p < 0.01) were significantly different among the study groups. In the case of IL-6, patients from Lima had a mean level of 16.2 pg/ml (healthy) and 48.3 pg/ml (COVID-19), meanwhile, patients from Huaraz had levels of 67.3 pg/ml (healthy) and 97.9 pg/ml (COVID-19). Regarding TNF-α, patients from Lima had a mean level of 25.9 pg/ml (healthy) and 61.6 pg/ml (COVID-19), meanwhile, patients from Huaraz had levels of 89.0 pg/ml (healthy) and 120.6 pg/ml (COVID-19). The levels of IL-2, IL-10 and IFN-γ were not significantly different in the study groups.Conclusion: Patients with COVID-19 residing at high-altitude tend to have higher levels of inflammatory cytokines compared to patients living at sea level, particularly IL-6 and TNF-α. A better understanding of the inflammatory response in different populations can contribute to the implementation of therapeutic and preventive approaches. Further studies evaluating more patients, a greater variety of cytokines and their clinical impact are required.

7 November 2021 in Antibiotics
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Journal Article
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GPGiancarlo Pérez-Lazo
Giancarlo Pérez-Lazo
WCWilmer Gianfranco Silva Caso
Wilmer Gianfranco Silva Caso
LVLuis J. del Valle
Luis J. del Valle
AMAdriana Morales-Moreno
Adriana Morales-Moreno
JBJosé Ballena-López
José Ballena-López
LILuis Ricardo Illescas
Luis Ricardo Illescas
The impact of respiratory coinfections in COVID-19 is still not well understood despite the growing evidence that consider coinfections greater than expected. A total of 295 patients older than 18 years of age, hospitalized with a confirmed diagnosis of moderate/severe pneumonia due to SARS-CoV-2 infection (according to definitions established by the Ministry of Health of Peru) were enrolled during the study period. A coinfection with one or more respiratory pathogens was detected in 154 (52.2%) patients at hospital admission. The most common coinfections were Mycoplasma pneumoniae (28.1%), Chlamydia pneumoniae (8.8%) and with both bacteria (11.5%); followed by Adenovirus (1.7%), Mycoplasma pneumoniae/Adenovirus (0.7%), Chlamydia pneumoniae/Adenovirus (0.7%), RSV-B/Chlamydia pneumoniae (0.3%) and Mycoplasma pneumoniae/Chlamydia pneumoniae/Adenovirus (0.3%). Expectoration was less frequent in coinfected individuals compared to non-coinfected (5.8% vs. 12.8%). Sepsis was more frequent among coinfected patients than non-coinfected individuals (33.1% vs. 20.6%) and 41% of the patients who received macrolides empirically were PCR-positive for Mycoplasma pneumoniae and Chlamydia pneumoniae.

18 June 2023 in Antibiotics
Verified
Journal Article
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SPStefany Plasencia-Rebata
Stefany Plasencia-Rebata
SLSaul Levy-Blitchtein
Saul Levy-Blitchtein
LVLuis J. del Valle
Luis J. del Valle
WCWilmer Gianfranco Silva Caso
Wilmer Gianfranco Silva Caso
IPIsaac Peña-Tuesta
Isaac Peña-Tuesta
MLMiguel Angel Aguilar Luis
Miguel Angel Aguilar Luis
(1) Background: Acinetobacter baumannii has become the most important pathogen responsible for nosocomial infections in health systems. It expresses several resistance mechanisms, including the production of β-lactamases, changes in the cell membrane, and the expression of efflux pumps. (2) Methods: A. baumannii was detected by PCR amplification of the blaOXA-51-like gene. Antimicrobial susceptibility to fluoroquinolones and aminoglycosides was assessed using the broth microdilution technique according to 2018 CLSI guidelines. Efflux pump system activity was assessed by the addition of a phenylalanine–arginine beta-naphthylamide (PAβN) inhibitor. (3) Results: A total of nineteen A. baumannii clinical isolates were included in the study. In an overall analysis, in the presence of PAβN, amikacin susceptibility rates changed from 84.2% to 100%; regarding tobramycin, they changed from 68.4% to 84.2%; for nalidixic acid, they changed from 73.7% to 79.0%; as per ciprofloxacin, they changed from 68.4% to 73.7%; and, for levofloxacin, they stayed as 79.0% in both groups. (4) Conclusions: The addition of PAβN demonstrated a decrease in the rates of resistance to antimicrobials from the family of quinolones and aminoglycosides. Efflux pumps play an important role in the emergence of multidrug-resistant A. baumannii strains, and their inhibition may be useful as adjunctive therapy against this pathogen.