Samuel Martínez-Vernaza

Hospital Universitario San Ignacio

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Sandra Valderrama

Pontificia Universidad Javeriana

CÁ

Carlos Álvarez

Fundación Universitaria Sanitas

Jorge Alberto Cortés

Universidad Nacional de Colombia

Kevin J. Blair

University of California, Los Angeles

María Alejandra Jaimes-Reyes

Hospital Universitario San Ignacio

Katherine García-Guzmán

Instituto Nacional de Cancerología

Sandra Gualtero-Trujillo

Hospital Universitario San Ignacio

Javier Garzón-Herazo

Hospital Universitario San Ignacio

Juliana Cuervo-Rojas

Pontificia Universidad Javeriana

Sonia Isabel Cuervo

Instituto Nacional de Cancerología

Cooperative Institutions

Pontificia Universidad Javeriana

Hospital Universitario San Ignacio

Universidad Nacional de Colombia

Fundación Universitaria Sanitas

Instituto Nacional de Cancerología

Hospital Militar Central

University of California, Los Angeles

Secretaría de Salud de Bogotá

Johns Hopkins University

Asociación Colombiana de Infectología

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Associated Factors for Mortality in a COVID-19 Colombian Cohort by Epidemic Wave: Is the Predominance of Mu Variant Relevant?

Carlos Álvarez Sandra Valderrama Ronaldo Silva Ilich Herbert De La Hoz Siegler Fabio Andrés Varón Vega

Objectives: To evaluate the association between Colombia's third wave when the Mu variant was predominant in Colombia and COVID-19 all-cause in-hospital mortality.Methods: In this retrospective cohort, we included hospitalized patients ≥18 years with SARS-CoV-2 infection between March 2020 to September 2021 in ten hospitals from three cities in Colombia. Description analysis, survival, and multivariate Cox regression analyses were performed to evaluate the association between the third epidemic wave and in-hospital mortality.Results: A total of 25,371 patients were included. The age-stratified time-to-mortality curves showed differences according to epidemic waves in patients ≥75 years (log-rank test p=0.012). In the multivariate Cox analysis, the third wave was not associated with increased mortality relative to the first wave (aHR 0.95; 95%CI 0.84-1.08), but there was an interaction between age ≥75 years and the third wave finding a lower HR for mortality (aHR 0.56, 95%CI 0.36-0.86).Conclusions: We did not find an increase in in-hospital mortality during the third epidemic wave in which the Mu variant was predominant in Colombia. The reduced hazard in mortality in patients ≥75 years hospitalized in the third wave could be explained by the high coverage of SARS-CoV-2 vaccination in this population and patients with underlying conditions.

2019-20 coronavirus outbreak

10.2139/ssrn.4330287

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1256. Antiretroviral Switching in Colombia: A Retrospective Cohort Study.

Open Forum Infectious Diseases (2022)

Shirley Vanessa Correa Forero Sandra Valderrama Samuel Martínez-Vernaza

Abstract Background Antiretroviral therapy (ART) for the human immunodeficiency virus (HIV) has improved life expectancy in people living with HIV/AIDS (PLWHA). Between 2.4% and 50% of PLWHA who initiate ART require a regimen switch within the first year. This variable range depends on local treatment guidelines, available ART, and the prevalence of resistance. We aimed to analyze the causes of ART Switch, time to ART switch and its associated factors in a Colombian Cohort. 1. a. Kaplan Meier Curves and Log-Rank test for time to antiretroviral therapy switch by sex in a cohort of people living with HIV in Colombia 2017-2019. Log-rank test, p: 0.0091. b. Kaplan Meier Curves and Log-Rank test for time to antiretroviral therapy switch by age in a cohort of people living with HIV in Colombia 2017-2019. Log rank test, p: <0.0001. c. Kaplan Meier Curves and Log-Rank test for time to antiretroviral therapy switch by CDC Stage in a cohort of people living with HIV in Colombia 2017-2019. Log rank test, p: 0.006. d. Kaplan Meier Curves and Log-Rank test for time to antiretroviral therapy switch by CD4 cell count in a cohort of people living with HIV in Colombia 2017-2019. Log rank test, p: 0.096 Methods We conducted a retrospective cohort study in 20 different HIV clinics including patients ≥18 years with confirmed HIV who underwent ART switching from 2017 to 2019 and with at least 6 months of follow up in their HIV Clinic. A time to event analysis and an exploratory Cox model were performed. Also, we conducted a logistic regression for comparing people with only one switch versus those who had 2 or more switches. Results 796 patients switched ART during the study period. Most of the patients were man (77.1%) and younger than 50 years (71.6%). The main cause of ART switch was tolerability (56.4%) followed by virologic failure (17.2%). Tolerability had a median time to switch of 12.2 months being the shortest, whereas the longest median time to switch was due to simplification (42.4 months). The Kaplan Meier curve and log-rank test for time to antiretroviral therapy switch by age, sex, CD4 count, and CDC stage are shown in Figure 1. In the Cox model we found that people with 50 years or older (HR= 0.6; 95% CI (0.5-0.7) and CDC stage 3 (HR= 0.8; 95% CI (0.6-0.9) had less hazard for switching ART over time. When comparing patients with only one ART switch versus those who had two or more ART switches, we found that having dyslipidemia increased the odds of switching ART more than one time (aOR=1.6; 95%CI (1.1-2.4). As opposed to having CD4 counts greater than 200 cell/mL which decreases the odds of having more than one ART switch. (aOR= 0.5; 95%CI (0.2-0.9) Table 1. Conclusion In this Colombian cohort, tolerability was the main cause of ART switch and the time to change the first ART is shorter than reports in other countries. Dyslipidemia and having CD4 counts smaller than 200 cells/mL increased the odds for requiring two or more changes. In Colombia is crucial to apply current recommendations of ART initiation in order to choose regimens with a better tolerability profile. Disclosures Sandra Valderrama, Infectologa, MSD: Advisor/Consultant.

Log-rank test

Regimen

10.1093/ofid/ofac492.1087

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Anal cytology screening in men who have sex with men with HIV at a university hospital in Bogotá, Colombia

International Journal of STD & AIDS (2022)

Ivonne Tatiana Ordóñez-Blanco Samuel Martínez-Vernaza Kevin J. Blair Camilo Quiroga Ellen Lowenstein

Background: Risk of anal squamous cell carcinoma (anal cancer) is greater among men who have sex with men (MSM) living with human immunodeficiency virus (HIV). We describe the frequency of and factors associated with abnormal anal cytology results in Colombian MSM living with HIV. Methods: This retrospective observational cohort study included MSM ≥18 years old living with HIV screened with anal cytology at Hospital Universitario San Ignacio in Bogotá, Colombia between January 2019 and February 2020. A multivariable log-binomial regression model estimated associations with abnormal anal cytology. Results: A total of 211 patients were included. Mean age was 35.6 years. Sixty-eight (32.3%) had an abnormal anal cytology result: ASC-US 33.8% ( n = 23); LSIL 60.3% ( n = 41); and HSIL 5.9% ( n = 4). MSM with an STI diagnosis in the previous 12 months (RR 1.48, [95% CI 1.03–2.12], p = 0.032) or with a CD4 + T cell count <200 (RR 2.08 [95% CI 1.16–3.73], p = 0.014) were significantly more likely to have abnormal anal cytology. Conclusions: These data provide crucial information to guide scale up of anal cancer screening at select centers in Colombia. Our results also suggest STI prevention efforts and improved virological control among MSM living with HIV may have the secondary benefit of reducing the risk of anal cancer.

10.1177/09564624221097742

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Tuberculosis extrapulmonar, un reto clínico vigente.

Universitas Médica (2020)

Sandra B. Amado-Garzón Sebastián Moreno-Mercado Samuel Martínez-Vernaza Javier Iván Lasso Apraez Andrés Laserna

Los dos tipos de manifestación clínica de la tuberculosis (TB) son la pulmonar y la extrapulmonar siendo la primera la más frecuente. No obstante, si bien se ha logrado disminuir la prevalencia en general, las cifras de la tuberculosis extrapulmonar (TBEP) se mantienen estables; se notificaron 896.000 casos nuevos en el mundo en 2017. Por lo general, se presenta por diseminación hematógena o linfática del bacilo del complejo Mycobacterium tuberculosis a otros órganos. Los sitios de compromiso más frecuentes son pleural, ganglionar, tracto gastrointestinal y osteoarticular. Otros menos habituales son el sistema nervioso central, piel, tracto genitourinario y vías aéreas superiores. Las manifestaciones clínicas de la TBEP son variables por su naturaleza paucibacilar y constituye un verdadero reto para los clínicos. La aproximación diagnóstica depende del sitio de compromiso, la facilidad de toma de la muestra, la sensibilidad de las pruebas y la distribución de la micobacteria en el tejido. La enfermedad usualmente responde al tratamiento estándar para TB y el tiempo ideal del régimen varía según el sitio afectado. El propósito de esta revisión es describir la presentación clínica y el proceso diagnóstico de la TBEP. Palabras clave:

10.11144/javeriana.umed61-4.reto

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805. Outbreak of Ralstonia pickettii Bacteremia Caused by Contaminated Hydromorphone in a Universitary Hospital in Bogota, Colombia

Open Forum Infectious Diseases (2021)

Shirley Vanessa Correa Forero Ivonne Tatiana Ordóñez Blanco Samuel Martínez-Vernaza Sandra Valderrama Gloria Cortés

Abstract Background Ralstonia pickettii are aerobic non fermenter gram negative bacilli isolated in water and soil. It is related to nosocomial infection outbreaks and considered an opportunistic pathogen. There have been outbreaks reports due to contaminated water systems and sterile drug solutions which mainly occurs during manufacturing. We present the report of an outbreak of R. pickettii bacteremia secondary to a contamination of hydromorphone vials. Methods In February 2021 an outbreak of R. pickettii bacteremia was identified. All isolates were from blood cultures with slow growth, thus indicating the culturing of liquid inputs, intravenous administration solutions and commonly used drugs among patients including hydromorphone. Mass spectrometry (MALDI-TOF) was used for the identification and automated microdilution to determine sensitivity to antimicrobials of the isolates and clonality analysis of genetic relationships was carried out using the DICE coefficient, UPGMA algorithm Results During the outbreak, 19 patients with R. pickettii bacteremia were identified The global attack rate was 1,9%. 11/19 (58%) were women and 13/19 (68%) of the isolations were from inward patients and 6/19 (32%) were from intensive care unit. Factors that could contribute to the appearance of the outbreak were underlying pathology, 2 patients with a diagnosis of diabetes mellitus, 10 patients with a diagnosis of arterial hypertension, 5 patients with obesity, 6 patients with heart disease, additionally 7 patients with a diagnosis of SARS COV 2 and 6 patients with the use of corticosteroids. The global attack rate was 1,9% and mortality was 31.5% (6 patients). R. pickettii was identified from two batches of hydromorphone by MALDI-TOF and the clonality study concluded that the isolates analyzed, were clonal with a 100% similarity. The associated mortality rate was 5/29 (26.3%). Conclusion We confirmed an outbreak of R. pickettii due to the contamination of two hydromorphone badges in Colombia. It is crucial to acknowledge the importance of infection control and surveillance during the COVID-19 pandemic as well as maintaining adequate quality control of medication production in order to avoid presenting this kind of outbreaks. Disclosures Sandra Liliana. Valderrama-Beltrán, MD, MSc, Biotoscana (Speaker’s Bureau)MSD (Grant/Research Support, Scientific Research Study Investigator, Research Grant or Support, Speaker’s Bureau)Pfiezer (Speaker’s Bureau)

Bacteremia

Cefepime

Hydromorphone

10.1093/ofid/ofab466.1001

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Protecting healthcare workers in the COVID-19 pandemic: respirator shortages and health policy responses in South America

Cadernos de Saúde Pública (2020)

Kevin J. Blair Samuel Martínez-Vernaza Eddy R. Segura José Luis Gallardo Barrientos Kent Garber

A proteção dos profissionais de saúde durante a pandemia da COVID-19: falta de respiradores e respostas a partir de políticas de saúde na América do Sul

Respirator

Pandemic

Economic shortage

2019-20 coronavirus outbreak

10.1590/0102-311x00227520

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Neumonía adquirida en la comunidad: una revisión narrativa

Universitas Médica (2018)

Samuel Martínez-Vernaza María Juliana Soto-Chávez Estefania Mckinley Sandra Gualtero Trujillo

La neumonía adquirida en la comunidad (NAC) continúa siendo una de las principales causas de mortalidad en Colombia, pues es responsable de 13 de cada 100.000 muertes. Su principal agente etiológico es el Streptococcus pneumoniae, seguido por Haemophilus influenzae y Staphylococcus aureus. Se han identificado algunos factores de riesgo como comorbilidades y factores de exposición epidemiológica, los cuales incrementan la posibilidad de contraer una infección por microrganismos específicos. Su diagnóstico debe basarse tanto en la clínica como en hallazgos paraclínicos e imagenológicos. Herramientas como las escalas CURB-65 y PSI asociadas al criterio clínico permiten calcular el riesgo de mortalidad y el área de atención del paciente según su clasificación. En esta revisión se consideran los diferentes elementos para una adecuada evaluación y manejo del paciente que cursa con NAC, el uso de algunos biomarcadores, situaciones especiales para apreciar, como la neumonía severa, y estrategias para una adecuada prevención.

10.11144/javeriana.umed59-4.neum

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Comparative outcomes of direct-acting antiviral treatment in patients with HIV-Hepatitis C co-infection: insights from a single center experience in Colombia.

PubMed (2023)

Hernan Vergara Samuel Martínez-Vernaza Alejandro De la Hoz Julián E. Barahona‐Correa Juan Pablo Ortiz

Direct-acting antivirals (DAA) were introduced to Latin America with the aim of eliminating hepatitis C (HCV) in the region. There are scarce data on the outcomes of people living with HIV and HCV treated with these medications in Colombia. This study compares the outcomes of patients with HIV-HCV co-infection and HCV mono-infection treated with DAAs.Retrospective observational study including patients ≥18 years old with HCV infection treated with DAAs from August 2017 to December 2019 in a comprehensive center in Colombia. The main outcome was sustained virologic response (SVR). Secondary outcomes included reinfection, relapse and adverse events.We included 223 individuals with HCV treated with DAAs; 142 (63.6%) individuals were mono-infected and 81 (36.3%) co-infected. Genotypes 1b (49.7%) and 4 (33.9%) were the most common. Overall SVR after DAA treatment was 96.8%. Relapse rate was 2.24%, reinfection rate was 6.28% and adverse events occurred in 27.8% of cases. SVR was comparable in patients with co- and mono-infection (95% vs 97.8%, p=0.245).DAA were effective in mono-infected (HCV) and co-infected (HCV/HIV) patients and reinfection was high in this last group.

Hepatitis C

Single Center

10.53854/liim-3103-11

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Molecular and Clinical Data of Antimicrobial Resistance in Microorganisms Producing Bacteremia in a Multicentric Cohort of Patients with Cancer in a Latin American Country

Microorganisms (2023)

Sergio Andrés Cruz-Vargas Laura García-Muñoz Sonia Isabel Cuervo Carlos Álvarez Carlos H. Saavedra-Trujillo

Patients with cancer have a higher risk of severe bacterial infections. This study aims to determine the frequency, susceptibility profiles, and resistance genes of bacterial species involved in bacteremia, as well as risk factors associated with mortality in cancer patients in Colombia. In this prospective multicenter cohort study of adult patients with cancer and bacteremia, susceptibility testing was performed and selected resistance genes were identified. A multivariate regression analysis was carried out for the identification of risk factors for mortality. In 195 patients, 206 microorganisms were isolated. Gram-negative bacteria were more frequently found, in 142 cases (68.9%): 67 Escherichia coli (32.5%), 36 Klebsiella pneumoniae (17.4%), and 21 Pseudomonas aeruginosa (10.1%), and 18 other Gram-negative isolates (8.7%). Staphylococcus aureus represented 12.4% (n = 25). Among the isolates, resistance to at least one antibiotic was identified in 63% of them. Genes coding for extended-spectrum beta-lactamases and carbapenemases, blaCTX-M and blaKPC, respectively, were commonly found. Mortality rate was 25.6% and it was lower in those with adequate empirical antibiotic treatment (22.0% vs. 45.2%, OR: 0.26, 95% CI: 0.1–0.63, in the multivariate model). In Colombia, in patients with cancer and bacteremia, bacteria have a high resistance profile to beta-lactams, with a high incidence of extended-spectrum beta-lactamases and carbapenemases. Adequate empirical treatment diminishes mortality, and empirical selection of treatment in this environment of high resistance is of key importance.

Bacteremia

10.3390/microorganisms11020359

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Citations (9)

Associated Factors for Mortality in a COVID-19 Colombian Cohort by Epidemic Wave: Is the Predominance of Mu Variant Relevant?

SSRN Electronic Journal (2022)

Carlos Álvarez Sandra Valderrama Ronaldo Silva Ilich Herbert De La Hoz Siegler Fabio Andrés Varón Vega

Background: The third epidemic wave reported the greatest number of deaths related to SARS-CoV-2 in Colombia. In this wave, the Mu variant was predominant in 75% of the cases. Therefore, we evaluated the association between Colombia's third wave and COVID-19 all-cause in-hospital mortality.Methods: In this retrospective cohort, we included hospitalized patients ≥18 years with SARS-CoV-2 infection between March 2020 to September 2021 in ten hospitals from three cities in Colombia. Description analysis, survival, and multivariate Cox regression analyses were performed to evaluate the association between the third epidemic wave and in-hospital mortality.Findings: A total of 25,371 patients were included. The age-stratified time-to-mortality analysis showed differences according to epidemic waves in patients ≥75 years (log-rank test p=0.012). In the multivariate Cox analysis, the third wave was not associated with increased mortality relative to the first wave (aHR 0.95; 95%CI 0.84-1.08), but there was an interaction between age ≥75 years and the third wave finding a lower HR for mortality (aHR 0.56, 95%CI 0.36-0.86).Interpretation: We did not find an increase in in-hospital mortality during the third epidemic wave in which the Mu variant was predominant in Colombia. The reduced hazard in mortality in patients ≥75 years hospitalized in the third wave could be explained by the high coverage of SARS-CoV-2 vaccination in this population and patients with underlying conditions. Funding Information: The World Health Organization funded this study.Declaration of Interests: CAM declares financial support from the World Health Organization to conduct the Solidarity Clinical Trial in Colombia. Also declares personal fees from Pfiezer, Aztra Zeneca and GSK, outside of the production of this study. SLVB declares personal fees as a member of the advisory boards from GSK, MSD, Biotoscana, outside of the production of this study. JACL declares Research Grant for antibiotic and antifungal stewardship for Pfiezer, outside of the production of this study. The rest of the authors don’t disclose potential conflict of interests.Ethics Approval Statement: The study was approved by each IRB or Ethics Committee of the participant institutions. All the methods in this study were conducted following national (Resolution 8430 of 1993, stated by The Colombian Health Ministry) and international (The declaration of Helsinki) standards. Informed consent was not required since there were no interventions performed.

2019-20 coronavirus outbreak

10.2139/ssrn.4297049

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