Alta sensibilidad a la mupirocina en aislados de Staphylococcus aureus que colonizan pacientes en hemodiálisis en una unidad renal de Medellín, Colombia / High mupirocin susceptibility in isolates of Staphylococcus aureus colonizing hemodialysis patients in a dialysis unit at Medellín

RESUMEN Objetivo: describir el porcentaje de resistencia a la mupirocina y a otros antibióticos en aislados de Staphylococcus aureus que colonizan pacientes en hemodiálisis. Métodos: estudio descriptivo en el que se incluyeron pacientes en hemodiálisis en una unidad renal de Medellín. La colonización por S. aureus fue evaluada en las fosas nasales y en la piel. La identificación bacteriana se realizó por PCR y la sensibilidad antibiótica se determinó por el sistema automatizado VITEK-2 y por el método E-test. Las características clínicas de los pacientes fueron evaluadas con la historia clínica. Resultados: se incluyeron 210 pacientes, de estos el 50,5 % (n = 106) fueron mujeres, con una mediana para la edad de 62 años (RIC 51,87-71,13). De las características clínicas se destacó el uso frecuente de antibióticos: 59 % (n = 124) y la historia de hospitalización: 69 % (n = 145). El porcentaje de colonización por S. aureus fue de 33,8 % (n = 71) y el sitio más frecuente de colonización fue las fosas nasales (19 %; n = 40). Todos los aislados fueron sensibles a la mupirocina por el método de VITEK-2. Sin embargo, un aislado presentó resistencia de bajo nivel a la mupirocina por E-test. La colonización por aislados resistentes a meticilina (SARM) fue de 4,8 % (n = 10) y estos presentaron, principalmente, resistencia solamente a la oxacilina (58,3 %; n = 7). Conclusión: la alta sensibilidad a la mupirocina en aislados de S. aureus colonizantes sugiere su uso como terapia profiláctica en pacientes en hemodiálisis con alto riesgo de infección. Es importante fortalecer los programas de uso racional de antibióticos para evitar la diseminación de mecanismos de resistencia a estos y a otros en las unidades renales.

SUMMARY Objective: To describe the resistance percentage to mupirocin and other antibiotics in Staphylococcus aureus isolates colonizing hemodialysis patients. Methods: A descriptive study was conducted at an outpatient dialysis center in Medellín and hemodialysis patients with catheter were included. Colonization by S. aureus was evaluated in nostrils and skin. Bacterial identification was performed by PCR and antibiotic susceptibility was determined by the Vitek-2 automated system and by E-test. Clinical information was obtained from medical records. Results: Two hundred and ten patients were included, of which 50.5% (n=106) were women, with a median for the age of 62 years (IQR 51,87-71,13). Among the clinical characteristics, the frequent use of antibiotics 59% (n=124) and the history of hospitalization 69% (n=145) were highlighted. The percentage of colonization by S. aureus was 33.8% (n=71) and the most frequent site of colonization was nostrils (19%; n=40). All isolates were susceptible to mupirocin by the method of Vitek-2. However, one isolate showed low level resistance to mupirocin by E-test. Colonization by methicillinresistant isolates (MRSA) was 4.8% (n=10); which presented mainly resistance only to oxacillin (58,3%; n = 7). Conclusion: The high susceptibility to mupirocin in isolates of colonizing S. aureus suggests its use as prophylactic therapy in hemodialysis patients with high risk of infection. It is important to strengthen programs for the rational use of antibiotics to prevent the spread of mechanisms of resistance to this and other antibiotics at dialysis units.

Knowledge, attitude, and practice regarding antibiotic use and resistance among medical students in Colombia: a cross-sectional descriptive study.

BACKGROUND: This study was designed to describe the knowledge, attitude, and practice regarding antibiotic use and resistance among medical students in Medellín, Colombia. METHODS: A cross-sectional study was conducted among medical students from three universities from September to December 2018. The sample size was calculated, the classrooms were visited, and those students who were willing to participate were invited to do so. The data collection instrument was constructed in three stages: i) the literature was systematically reviewed, ii) the items from the studies identified were extracted, and iii) item reduction was performed with exploratory factor analysis. Data were analyzed by calculating absolute and relative frequencies and means for quantitative variables. The indexes of knowledge, attitude, and practice were transformed to a scale from 0 (worst possible score) to 100. Comparisons were performed using the Mann-Whitney U test, Kruskall-Wallis H test, and linear regressions. RESULTS: Five hundred and thirty-two medical students were included with a response rate of 96%. Of the total participants, 49.1% reported having used antibiotics within the past year. Regarding knowledge, only 18.2% had heard of the term "antimicrobial stewardship" and 69.3% were aware that empiric antibiotic therapy contributes to antibiotic resistance. Regarding attitude, 11.6% considered that antibiotics should be discontinued as soon as symptoms disappear and 24.6% stated that it is better to prescribe broad-spectrum antibiotics to ensure that the patient is cured. Regarding practice, 28.5% recognized that resistance is a multifactorial problem, but they do not act on it because they consider that individual actions would have little impact. The adjusted linear regression showed that the variables associated with knowledge, attitude, and practice were socioeconomic status, training cycle, university, previous experience of research or education, the general perception of the training received, and antibiotic consumption. CONCLUSION: Knowledge, attitude, and practice differ widely depending on the university, training cycle, and socioeconomic status, and a significant proportion of students consider that the standard of training received at the university on antibiotics and bacterial resistance is poor or mediocre. These findings show that there is a need to strengthen the medical students' curriculum on antibiotics, mechanisms of antibiotic resistance, and the prudent use of antibiotics as an important strategy to combat problem-resistant public health, primarily in endemic countries.

Knowledge regarding antibiotic use among students of three medical schools in Medellin, Colombia: a cross-sectional study.

BACKGROUND: The objective of the present study was to describe the knowledge regarding the antibiotic therapy of students of three medical schools in Medellín, Colombia. METHODS: The study population comprised medical students who were enrolled in three universities. The instrument contained questions regarding their current academic term, the university, the perceived quality of the education received on antibiotic therapy and bacterial resistance, and specific questions on upper respiratory tract infections, pneumonia, urinary tract infections, and skin and soft tissue infections. The information was analyzed by calculating frequencies and measures of dispersion and central tendency. Knowledge regarding the treatment for each type of infection was compared using the Mann-Whitney U test and the Kruskal-Wallis H test. RESULTS: We included 536 medical students, of which 43.5% students consider that the university has not sufficiently trained them to interpret antibiograms and 29.6% students consider that the quality of information received on the subject at their university ranges from regular to poor. The mean score for knowledge regarding antibiotic therapy for upper respiratory tract infections was 44.2 (9.9) on a scale from 0 to 100. The median score with regard to the treatment of pneumonia was 52.9 (14.7), that of urinary tract infection was 58.7 (14.8), and that of skin and soft tissue infections was 63.1 (19.4). The knowledge regarding antibiotic therapy for upper respiratory tract infections, pneumonia, and urinary tract infection does not improve with the academic term, the university, or perceived quality of the education received. CONCLUSION: A large proportion of medical students perceive that the training received from the university is insufficient with regard to antibiotic use and bacterial resistance, which is consistent with the limited knowledge reflected in the selection of antibiotic treatment for respiratory, urinary tract, and skin and soft tissue infections. Overall, the situation was identical among all universities, and it did not significantly increase with the completion of an academic term.

Influenza aviar: la gripa del pollo / Avian influenza: chicken's flu

La influenza aviar es causada por el virus de la influenza tipo A, perteneciente a la familia Ortomyxoviridae. Es un agente zoonotico que posee glicoproteínas de membrana con actividad de neuroraminidasa o hemaglutinina, que le otorgan gran variación antigénica llevando a la aparición de infección respiratoria aguda autolimitada tanto en animales como en humanos. En Colombia, ocurren brotes epidémicos de manera periódica, principalmente en épocas de lluvia (de marzo a junio y de septiembre a noviembre), pero se ha establecido que el virus circula de manera permanente durante todo el año. La aparición de nuevas cepas contra las cuales la población no posee inmunidad lleva a la aparición de pandemias. Se han documentado varias muertes en humanos en el sur de Asia relacionadas con la cepa H5N1, lo cual junto los antecedentes históricos, la epidemiología y la ecología de los reservorios naturales, permiten suponer la aparición de una nueva pandemia, que en caso de presentarse podría afectar entre el 15 por ciento y 35 por ciento de la población mundial. Las vacunas disponibles en la actualidad no ofrecen protección contra el virus H5N1. Asimismo, medicamentos antivirales como la amantadina no actúan sobre esta cepa y solo los inhibidores de la neuraminidasa como el Oseltamivir han demostrado alguna eficacia terapéutica