Nonparametric Population Pharmacokinetic Modeling of Isoniazid in Colombian Patients With Tuberculosis.

BACKGROUND: Isoniazid (INH) is a first-line antituberculosis (TB) agent with a pharmacokinetic profile characterized by high interindividual variation; however, population pharmacokinetic studies in patients with TB are scarce. The aim was to develop a population model for INH in Colombian patients with TB suitable for predicting drug exposure and assessing the probability of target attainment of pharmacodynamic goals. METHODS: Ten hospitalized adult patients with TB undergoing INH treatment were recruited. After an 8-hour fasting, subjects took 300 mg of INH, and 10 samples were taken from 0 to 12 hours. INH was quantified by high-performance liquid chromatography-UV, and data were analyzed with the Pmetrics R package software. A Monte Carlo simulation with the model parameters was run to determine the probability of target attainment for optimal efficacy. RESULTS: The best model included 2 compartments, first-order absorption (Ka), delayed absorption (Tlag), and linear clearance (CL). Median Tlag was 0.25 hours, 5.54 hour for Ka, (Equation is included in full-text article.)for CL, (Equation is included in full-text article.)for the volume of the central compartment (Vc), 1.04 L/h for intercompartmental clearance (Q), and 788 L for the volume of the peripheral compartment (Vp). CL and Vc were allometrically scaled on basis of the normalized body weight. CONCLUSIONS: The Monte Carlo simulation indicated that 300 mg of INH per day is appropriate for Mycobacterium tuberculosis strains with minimal inhibitory concentration (MIC) up to 0.03 mg/L (target: area under the concentration-time curve/MIC >597); however, to cover strains with MIC up to 0.125 mg/L (80% of clinical isolates), a dose of 900 mg per day would be required.

[Risk factors for multidrug-resistant Pseudomonas aeruginosa infection, in a tertiary hospital in Colombia]. / Factores de riesgo para infección por Pseudomonas aeruginosa multi-resistente en un hospital de alta complejidad.

INTRODUCTION: multi-resistant Pseudomonas aeruginosa (MR) is frequently associated with healthcare infections. Its epidemiology is complex and few studies help to understand it. A study about risk factors associated with this type of bacteria is needed. OBJECTIVE: To determine risk factors associated with MR P. aeruginosa infection in hospitalized patients from the Hospital Universitario San Vicente Foundation-Medellin. MATERIALS AND METHODS: case-control study to identify risk factors associated with infection by MR P. aeruginosa. RESULTS: 140 patients were included, 70 in each group. Bivariate analysis found association with previous use of carbapenems (OR 3.12 - IC 1.21 to 8.03, p = 0.02), aminoglycosides (OR 5.09 - CI: 1.38 to 18, 77, p = 0.01) and days of stay prior to isolation of the organism (OR 1.03 - CI: 1.01-1.05, p = 0.01). In multivariate analysis MR P. aeruginosa infection was associated with hospital stay (OR 1.03 - IC 1.01 to 1.05), use of aminoglycosides (OR 1.30 to 19.28) and treatment with two or more antimicrobials in the last 30 days (OR 3.09 - CI: 1.26 to 7.58). The risk of developing infection was 3% per day of hospital stay prior to isolation of the agent. CONCLUSION: Developing MR P. aeruginosa infection was associated with prior use of antimicrobials and prior hospital stay.

[Multidrug-resistant Klebsiella pneumoniae, predisposing factors and associated mortality in a tertiary-care hospital in Colombia]. / Klebsiella pneumoniae multi-resistente, factores predisponentes y mortalidad asociada en un hospital universitario en Colombia.

INTRODUCTION: Bacterial resistance to antibiotics is a serious public health problem that is increasing worldwide. Resistant (R) Klebsiella pneumoniae is one of the main pathogens isolated in nosocomial infections. The aim of this study was to explore risk factors associated with the acquisition of infection by R-K. pneumoniae and mortality. METHODS: Prospective cohort study conducted in a hospital of high complexity of Medellin, October/2009-April/2010. The exposed group was defined as patients infected with R-K. pneumoniae (producing b-lactamases or carbapenemases). In order to identify risk factors associated with infection by R-K. pneumoniae and 30 day mortality, logistic regression and Cox proportional hazards regression were used. RESULTS: 243 patients were included in the study, 84 infected with R-K. pneumoniae and 159 infected with susceptible K. pneumoniae. Female sex (OR = 2.51 95% 1.37 to 4.6), the co-existence of cardiovascular disease (OR = 2.13 95% CI 1.14 to 3.99), previous use of ceftriaxone (OR = 9.52 95% CI 2.63 to 34.46) and carbapenems (OR = 4.23 95% CI 2.41 to 7.42) were risk factors associated to infection with R-K. pneumoniae. Some predictors of mortality were malignant neoplasia (HR = 4.43 95% CI 2.13 to 9.22) and mechanical ventilation (HR = 3.81 95% CI 1.99 to 7.28). There was no difference in 30-day mortality when comparing patients in both groups. CONCLUSIONS: Female gender, cardiovascular disease and previous use of antimicrobials were associated with infection by R-K. pneumoniae. Thirty-day mortality was similar in both groups of patients.

Highly sensitive scent-detection of COVID-19 patients in vivo by trained dogs.

Timely and accurate diagnostics are essential to fight the COVID-19 pandemic, but no test satisfies both conditions. Dogs can scent-identify the unique odors of volatile organic compounds generated during infection by interrogating specimens or, ideally, the body of a patient. After training 6 dogs to detect SARS-CoV-2 by scent in human respiratory secretions (in vitro diagnosis), we retrained 5 of them to search and find the infection by scenting the patient directly (in vivo screening). Then, efficacy trials were designed to compare the diagnostic performance of the dogs against that of the rRT-PCR in 848 human subjects: 269 hospitalized patients (COVID-19 prevalence 30.1%), 259 hospital staff (prevalence 2.7%), and 320 government employees (prevalence 1.25%). The limit of detection in vitro was lower than 10-12 copies ssRNA/mL. During in vivo efficacy experiments, our 5 dogs detected 92 COVID-19 positive patients among the 848 study subjects. The alert (lying down) was immediate, with 95.2% accuracy and high sensitivity (95.9%; 95% C.I. 93.6-97.4), specificity (95.1%; 94.4-95.8), positive predictive value (69.7%; 65.9-73.2), and negative predictive value (99.5%; 99.2-99.7) in relation to rRT-PCR. Seventy-five days after finishing in vivo efficacy experiments, a real-life study (in vivo effectiveness) was executed among the riders of the Metro System of Medellin, deploying the human-canine teams without previous training or announcement. Three dogs were used to examine the scent of 550 volunteers who agreed to participate, both in test with canines and in rRT-PCR testing. Negative predictive value remained at 99.0% (95% C.I. 98.3-99.4), but positive predictive value dropped to 28.2% (95% C.I. 21.1-36.7). Canine scent-detection in vivo is a highly accurate screening test for COVID-19, and it detects more than 99% of infected individuals independent of key variables, such as disease prevalence, time post-exposure, or presence of symptoms. Additional training is required to teach the dogs to ignore odoriferous contamination under real-life conditions.

[Sociodemographic and clinical characteristics of patients infected with Leptospira spp. treated at four hospitals in Medellín, Colombia, 2008-2013].

INTRODUCTION: Leptospirosis remains a significant health problem in tropical regions including Latin America, where its presentation is 100 times higher than that observed in other regions of the world. Mortality reaches 10% in severe cases. Its diagnosis is challenging because clinical manifestations during the initial phase are non-specific and because of limited availability of diagnostic tests. OBJECTIVE: To describe the demographic and clinical characteristics and the outcomes in hospitalized patients with leptospirosis. MATERIALS AND METHODS: This retrospective study included patients treated at four institutions in Medellín between January, 2009, and December, 2013, with a compatible clinical picture and a positive IgM for Leptospira spp. RESULTS: We included 119 patients, 80% male, and 58% of rural origin. The mean duration of symptoms was 9.6 days (SD=9.6). Eighty nine per cent of patients had fever; 62%, jaundice; 74%, myalgia; 46%, diarrhea; 41%, hepatomegaly; 13%, splenomegaly, and 13%, conjunctival injection. Fifty four per cent of patients had impaired renal function; 32%, pulmonary compromise, and 13%, liver failure. Sixteen per cent required admission to the ICU; 12%, mechanical ventilation, and 11%, vasopressor therapy.Weil's syndrome occurred in 38.6% and 5% died. The average hospital stay was 11 days (SD=9.6). CONCLUSIONS: In this population, the clinical manifestations and complications of leptospirosis were similar to those reported in the literature. We observed a relatively low overall mortality in relation to global statistics.

Dependence to legally prescribed opioid analgesics in a university hospital in Medellin-Colombia: an observational study.

BACKGROUND: In some countries the misuse and diversion of prescribed opioid analgesic is increasing considerably, but there is no official data regarding the situation in Colombia. The aim of this study was to identify all dependent to opioid analgesics legally prescribed patients that were treated in a University Hospital in Medellin, Colombia during 4 years and to characterize this population. METHODS: Observational study in a University Hospital in Medellin, Colombia, searching for patients with ICD-10 codes related with opioid related disorders, adverse events or pain and treated between January 2011 and December 2014. RESULTS: Sixty patients with opioid dependence according to DSM-IV criteria were found from 3332 clinical charts reviewed. The median age was 43 years. Although all patients met the DSM-IV criteria, 33 % of patients were wrongly diagnosed by other ICD-10 codes. Almost all patient (88 %) initiated opioids after medical prescription although the adherence to pain scale was low (25 %). The median time of consumption was 48 months. Tramadol was the opioid more frequently used by patients, followed by morphine and oxycodone. A statistically significant higher consumption of other psychotropic substances was observed in male than female (P = 0.005 by Fisher's test). After be diagnosed, 55 % of patients gone a methadone-based replacement therapy. CONCLUSION: Legally prescribed opioid dependence was belatedly diagnosed in 60 patients in a University hospital, after prolonged use of drugs to treat chronic pain and with low adherence to pain scale or guidelines. This is the first report in Colombia.

Factores de riesgo para vasoespasmo cerebral en pacientes con hemorragia subaracnoidea espontánea / Risk Factors for Cerebral Vasospasm in Patients with Spontaneous Subarachnoid Hemorrhage

Objetivos: Establecer la asociación de vasoespasmo cerebral detectado por Doppler transcraneal y la condición clínica, de acuerdo con la escala de la Federación Mundial de Sociedades de Neurocirugía, y con otros factores de riesgo en pacientes con hemorragia subaracnoidea espontánea. Materiales y métodos: Estudio observacional retrospectivo de casos y controles, con 141 pacientes diagnosticados con hemorragia subaracnoidea espontánea a quienes se les realizó Doppler transcraneal de seguimiento entre el 8 de marzo de 2011 y el 15 de marzo de 2015. Del total de pacientes se escogieron 47 con vasoespasmo detectado por Doppler transcraneal y 2 controles, sin vasoespasmo, por cada caso (94 pacientes). En las historias clínicas y las imágenes de los pacientes se estableció la asociación entre la detección de vasoespasmo por Doppler transcraneal con la condición clínica neurológica en el momento del examen, y otros factores de riesgo. Para el análisis de las variables cualitativas se utilizaron frecuencias absolutas y relativas. Para variables cuantitativas se utilizó la prueba de Shapiro Wilk. Los datos con distribución normal se presentan con medias y desviaciones estándar y aquellos sin distribución normal con medianas y rangos intercuartiles. Se evaluó la homogeneidad entre los dos grupos a través de la prueba de Chi cuadrado y el test de homogeneidad de varianzas (Levene) de acuerdo con el tipo de variable. Se consideró estadísticamente significativa una p ≤ 0,05. Resultados: El análisis bivariado no demostró resultados estadísticamente significativos en la relación entre la condición clínica neurológica y el vasoespasmo, pero sí encontró que pacientes menores de 50 años de edad presentaron más vasoespasmo (OR de 3,55 [95 % IC; 1,52-7,39]), y p: 0,003 que los de mayor edad. Conclusiones: Los pacientes menores de 50 años de edad tienen más riesgo de desarrollar vasoespasmo y no existe asociación entre la condición clínica y los resultados del Doppler transcraneal.

Objectives: Establish the association between cerebral vasospasm, detected by transcranial doppler, with the clinical condition according to the scale of the World Federation of Neurosurgical Societies (WFNS) and other risk factors in patients with spontaneous subarachnoid hemorrhage. Materials and methods: This is an observational retrospective case-control study, including 141 patients with a diagnosis of spontaneous subarachnoid hemorrhage who underwent transcranial doppler monitoring in the radiology department of the University Hospital San Vicente Foundation (HUSVF) from 8 March 2011 to 15 March 2015. Of the total number of patients with subarachnoid hemorrhage, 47 cases with vasospasm, detected by transcranial Doppler, and two controls without vasospasm (94 patients) were consecutively chosen. Subsequently, we review the medical records and images stored in the hospital´s radiology department and established the association between vasospasm detection by trasncranial Doppler with clinical neurological status at the time of the study and other risk factors. For the analysis of the qualitative variables, absolute and relative frequencies were used. Quantitative variables were tested for normal distribution with a Shapiro Wilk test. Data with normal distribution were presented with means and standard deviations and those without normal distribution with medians and interquartile ranges. Homogeneity between the two groups were evaluated by Chi-square test and test for homogeneity of variances, Levene's test, according to the type of variable (qualitative and quantitative respectively). Results were considered statistically significant if p ≤ 0.05. Results: Data from 141 patients (47 cases and 94 controls) were analyzed. The bivariate analysis didn´t show statistically significant results in the relationship between vasospasm and clinical neurological condition but found that patients younger than 50 years had more vasospasm. In the adjusted model for patients with this age, the OR was 3.55 (95 % CI, 1.52-7.39) and p: 0.003 when compared with older patients. Conclusions: This study found that patients under 50 have a higher risk of developing vasospasm compared with older patients and that there is no association between clinical condition and the results of transcranial Doppler.

Características sociodemográficas y clínicas de pacientes con infección por Leptospira spp. atendidos en cuatro centros hospitalarios de Medellín, Colombia, 2008-2013 / Sociodemographic and clinical characteristics of patients infected with Leptospira spp. treated at four hospitals in Medellín, Colombia, 2008-2013

Resumen Introducción: La leptospirosis continúa siendo un problema significativo de salud en regiones tropicales, incluidos los países de Latinoamérica, donde es 100 veces más frecuente que en otras regiones del mundo. En los cuadros graves de la enfermedad, su mortalidad alcanza el 10 %. Su diagnóstico es un reto debido a que las manifestaciones clínicas en la fase inicial son inespecíficas y a la poca disponibilidad de pruebas diagnósticas. Objetivo: Describir las características sociodemográficas y clínicas, y el desenlace de la enfermedad en pacientes hospitalizados con leptospirosis. Materiales y métodos: Es un estudio retrospectivo que incluyó pacientes atendidos en cuatro instituciones de Medellín, entre enero de 2009 y diciembre de 2013, con un cuadro clínico sugestivo e IgM positiva para Leptospira spp. Resultados: Se incluyeron 119 pacientes, 80 % hombres y 58 % de procedencia rural. La duración promedio de los síntomas fue de 9,6 días (DE=9,6). El 89 % de los pacientes presentó fiebre; el 62 %, ictericia; el 74 %, mialgias; el 46 %, diarrea; el 41 %, hepatomegalia; el 13 %, esplenomegalia, y 13 %, enrojecimiento de los ojos. En 54 % de los pacientes hubo deterioro de la función renal, en 32 %, compromiso pulmonar y, en 13 %, falla hepática. El 16 % de los pacientes requirió atención en la unidad de cuidados intensivos, el 12 %, asistencia respiratoria mecánica, y el 11 %, administración de vasopresores. En 38,6 % de ellos la enfermedad cursó con síndrome de Weil y el 5 % falleció. La duración promedio de la hospitalización fue de 11 días (DE=9,6). Conclusiones:. La leptospirosis en esta población tuvo manifestaciones clínicas y complicaciones similares a las reportadas en la literatura científica. Se observó una mortalidad general relativamente baja comparada con las estadísticas mundiales.

Abstract Introduction: Leptospirosis remains a significant health problem in tropical regions including Latin America, where its presentation is 100 times higher than that observed in other regions of the world. Mortality reaches 10% in severe cases. Its diagnosis is challenging because clinical manifestations during the initial phase are non-specific and because of limited availability of diagnostic tests Objective: To describe the demographic and clinical characteristics and the outcomes in hospitalized patients with leptospirosis. Materials and methods: This retrospective study included patients treated at four institutions in Medellín between January, 2009, and December, 2013, with a compatible clinical picture and a positive IgM for Leptospira spp. Results: We included 119 patients, 80% male, and 58% of rural origin. The mean duration of symptoms was 9.6 days (SD=9.6). Eighty nine per cent of patients had fever; 62%, jaundice; 74%, myalgia; 46%, diarrhea; 41%, hepatomegaly; 13%, splenomegaly, and 13%, conjunctival injection. Fifty four per cent of patients had impaired renal function; 32%, pulmonary compromise, and 13%, liver failure. Sixteen per cent required admission to the ICU; 12%, mechanical ventilation, and 11%, vasopressor therapy. Weil's syndrome occurred in 38.6% and 5% died. The average hospital stay was 11 days (SD=9.6). Conclusions: In this population, the clinical manifestations and complications of leptospirosis were similar to those reported in the literature. We observed a relatively low overall mortality in relation to global statistics.

Supervivencia libre de enucleación de pacientes con diagnóstico de retinoblastoma tratados con quimioterapia intraarterial en el Hospital Universitario de San Vicente Fundación / Enucleation free survival of patients with retinoblastoma diagnosis treated with intraarterial chemotherapy at University-Based San Vicente Fundacion Hospital

Objetivo: describir la supervivencia libre de enucleación, respuesta al tratamiento y complicaciones de los pacientes sometidos a tratamiento con quimioterapia intraarterial (QIA) para el control del retinoblastoma en el Hospital Universitario de San Vicente Fundación (HUSVF). Tipo de estudio: estudio de cohortes. Materiales y Métodos: se incluyeron todos los pacientes con diagnóstico de retinoblastoma tratados en el husvf con qia supraselectiva de la arteria oftálmica entre agosto del 2011 y agosto de 2013. Resultados: se realizó tratamiento a 21 pacientes, 24 ojos, en un periodo de 23.5 meses. La edad media al momento de inicio de la QIA fué 19 meses (rango 5-60 meses) con un seguimiento promedio de 9.3 meses (rango 3 semanas a 23.5 meses). Se realizaron 78 cateterizaciones, siendo 9 de ellas bilaterales. El salvamento ocular se alcanzó en el 100% de los Grupo A (n1), 100% B (n=2), 100% C (n=5) y 87.5% D (n=16), según la Clasificación Internacional para Retinoblastoma (CIRB). Sólo se reportaron dos eventos adversos importantes, una hemiparesia transitoria y una reacción alérgica severa. Ninguno de los pacientes ha fallecido, ha tenido compromiso metastásico o necesidad de radioterapia externa. Sólo se realizaron dos enucleaciones. La media de supervivencia de los 24 globos oculares tratados es de 10.4 meses ± 1.6. La media de supervivencia de los 21 pacientes tratados es de 10.4 meses ±1.7. Conclusiones: los resultados muestran una respuesta satisfactoria, constituyéndose la QIA como procedimiento seguro y con baja tasa de complicaciones en el tratamiento del retinoblastoma.

Purpose: to describe globe salvage, treatment response and complications of patients following intra-arterial chemotherapy (IAC) for retinoblastoma at Hospital Universitario de San Vicente Fundacion (HUSVF). Type of study: Cohort Study. Materials and methods: We included all patients diagnosed with retinoblastoma and treated with IAC between from August 2011 to August 2013. Results: A total of 21 patients, with a total of 24 eyes, were treated with IAC over a period of 23.5 months. The mean age of patients at time of treatment was 19 months (range 5-60 months) with a mean follow-up time of 9.3 months (range 3 weeks to 23.5 months). 78 catheterizations were performed, nine of them being bilateral. Ocular salvage rate was achieved in 100% of the Group A (n1), 100% in group B (n = 2), 100% in group C (n = 5) and 87.5% in group D (n = 16), according to the International Classification for Retinoblastoma. Only two major adverse events were reported, a transient hemiparesis and a severe allergic reaction. No deaths, metastatic involvement or need for external beam radiotherapy were reported. Two eyes, from group D, required enucleation. The mean survival rate of 24 eyes treated was 10.4 months ± 1.6. The mean survival rate of the 21 patients treated was 10.4 ± 1.7 months. Conclusions: The results show a satisfactory response, becoming the IAC a safe procedure with a low complication rate in retinoblastoma treatment.

Factores de riesgo para infección por Pseudomonas aeruginosa multi-resistente en un hospital de alta complejidad / Risk factors for multidrug-resistant Pseudomonas aeruginosa infection, in a tertiary hospital in Colombia

Introduction: multi-resistant Pseudomonas aeruginosa (MR) is frequently associated with healthcare infections. Its epidemiology is complex and few studies help to understand it. A study about risk factors associated with this type of bacteria is needed. Objective: To determine risk factors associated with MR P. aeruginosa infection in hospitalized patients from the Hospital Universitario San Vicente Foundation-Medellin. Materials and Methods: case-control study to identify risk factors associated with infection by MR P. aeruginosa. Results: 140 patients were included, 70 in each group. Bivariate analysis found association with previous use of carbapenems (OR 3.12 - IC 1.21 to 8.03, p = 0.02), aminoglycosides (OR 5.09 - CI: 1.38 to 18, 77, p = 0.01) and days of stay prior to isolation of the organism (OR 1.03 - CI: 1.01-1.05, p = 0.01). In multivariate analysis MR P. aeruginosa infection was associated with hospital stay (OR 1.03 - IC 1.01 to 1.05), use of aminoglycosides (OR 1.30 to 19.28) and treatment with two or more antimicrobials in the last 30 days (OR 3.09 - CI: 1.26 to 7.58). The risk of developing infection was 3% per day of hospital stay prior to isolation of the agent. Conclusion: Developing MR P. aeruginosa infection was associated with prior use of antimicrobials and prior hospital stay.

Introducción: Pseudomonas aeruginosa multi-resistente (MR) es causa frecuente de infecciones asociadas al cuidado de la salud, su epidemiología es compleja y hay pocos estudios que permiten comprenderla. El estudio de los factores de riesgo asociados a este tipo de bacterias es necesario para la implementación de estrategias de control de las mismas. Objetivo: Determinar factores de riesgo asociados a infección por P. aeruginosa MR en pacientes hospitalizados en el Hospital Universitario de San Vicente Fundación-Medellín. Materiales y Métodos: Estudio analítico con abordaje como casos y controles para determinar factores de riesgo asociados a infección por P. aeruginosa MR. Resultados: Se incluyó un total de 140 pacientes, 70 en cada grupo. En el análisis bivariado se encontró asociación con el uso previo de carbapenémicos (OR 3,12- IC 1,21-8,03; p: 0,02), aminoglucósidos (OR 5,09- IC: 1,38-18,77; p: 0,01) y el tiempo por día de estancia previo al aislamiento (OR 1,03- IC: 1,01-1,05; p: 0,01). En el análisis multivariado hay asociación entre la estancia hospitalaria (OR 1,03- IC 1,01-1,05), el uso de aminoglucósidos (OR 1,30-19,28) y el uso de dos o más antimicrobianos en los últimos 30 días (OR 3,09- IC: 1,26-7,58) con el desarrollo de infecciones por P. aeruginosa MR. El riesgo de desarrollar una infección por esta bacteria fue de 3% por cada día de estancia hospitalaria previo al aislamiento. Conclusión: El desarrollar infección por P. aeruginosa MR se asoció con el uso previo de antimicrobianos y con el tiempo previo de estancia hospitalaria.

Klebsiella pneumoniae multi-resistente, factores predisponentes y mortalidad asociada en un hospital universitario en Colombia / Multidrug-resistant Klebsiella pneumoniae, predisposing factors and associated mortality in a tertiary-care hospital in Colombia

Introduction: Bacterial resistance to antibiotics is a serious public health problem that is increasing worldwide. Resistant (R) Klebsiella pneumoniae is one of the main pathogens isolated in nosocomial infections. The aim of this study was to explore risk factors associated with the acquisition of infection by R-K. pneumoniae and mortality. Methods: Prospective cohort study conducted in a hospital of high complexity of Medellin, October/2009-April/2010. The exposed group was defined as patients infected with R-K. pneumoniae (producing b-lactamases or carbapenemases). In order to identify risk factors associated with infection by R-K. pneumoniae and 30 day mortality, logistic regression and Cox proportional hazards regression were used. Results: 243 patients were included in the study, 84 infected with R-K. pneumoniae and 159 infected with susceptible K. pneumoniae. Female sex (OR = 2.51 95% 1.37 to 4.6), the co-existence of cardiovascular disease (OR = 2.13 95% CI 1.14 to 3.99), previous use of ceftriaxone (OR = 9.52 95% CI 2.63 to 34.46) and carbapenems (OR = 4.23 95% CI 2.41 to 7.42) were risk factors associated to infection with R-K. pneumoniae. Some predictors of mortality were malignant neoplasia (HR = 4.43 95% CI 2.13 to 9.22) and mechanical ventilation (HR = 3.81 95% CI 1.99 to 7.28). There was no difference in 30-day mortality when comparing patients in both groups. Conclusions: Female gender, cardiovascular disease and previous use of antimicrobials were associated with infection by R-K. pneumoniae. Thirty-day mortality was similar in both groups of patients.

Introducción: La resistencia bacteriana a antimicrobianos es un grave problema de salud pública que va aumentando en el mundo. Klebsiella pneumoniae resistente (R) es uno de los principales patógenos aislado en infecciones hospitalarias. El objetivo de este estudio fue explorar factores de riesgo asociados con la adquisición de infección por K. pneumoniae R y con mortalidad. Metodología: Estudio de cohorte prospectivo realizado en un hospital de alta complejidad de Medellín, octubre/2009-abril/2010. El grupo expuesto se definió como pacientes infectados por K. pneumoniae R (productora de β-lactamasas de espectro extendido o carbapenemasas). Se hicieron regresión logística para identificar los factores de riesgo asociados con infección por K. pneumoniae R, y regresión de riesgos proporcionales de Cox para identificar los factores asociados con mortalidad a 30 días. Resultados: Se incluyeron 243 pacientes al estudio, 84 infectados con K. pneumoniae R y 159 con K. pneumoniae sensible.El sexo femenino (OR = 2,51 IC95% 1,37-4,6), la co-existencia de enfermedad cardiovascular (OR = 2,13 IC 95% 1,14-3,99), uso previo de ceftriaxona (OR = 9,52 IC95% 2,63-34,46) y carbapenémicos (OR = 4,23 IC95% 2,41-7,42) fueron factores de riesgo asociados con la probabilidad de infectarse por K. pneumoniae R. Algunos factores predictores de mortalidad fueron las neoplasias malignas (HR = 4,43 IC95% 2,13-9,22) y la ventilación mecánica (HR = 3,81 IC95% 1,99-7,28). No hubo diferencia en la mortalidad a 30 días al comparar los pacientes de ambos grupos. Conclusiones: El sexo femenino, la enfermedad cardiovascular y el uso previo de antimicrobianos se vieron asociados con infección por K. pneumoniae R. La mortalidad a 30 días fue similar en ambos grupos de pacientes.