Rastreo del cáncer colorrectal: Conocimiento y actitud de la población / Screening colorectal cancer: Perception and behavior of the population

El rastreo de cáncer colorrectal (CCR) cuenta con fuertes evidencias en su favor. Datos preliminares indican que a pesar de ello no se lleva a cabo con la frecuencia adecuada. Se intenta aquí determinar, dentro de un Sistema de Salud que cuenta con los recursos necesarios, los elementos que facilitan o generan barreras para concretar esta práctica preventiva, cuántos individuos lo ponen en práctica y qué predice esta conducta. Se realizó una encuesta telefónica a los afiliados de una Obra Social de empleados de la Universidad de Buenos Aires, de los que 132 completaron el cuestionario (tasa de respuesta 70%). Los elementos considerados facilitadores del rastreo obtuvieron respuestas afirmativas en el 64 a 97%, mientras que los que definían barreras un 11 a 27%. En este último grupo, una categoría diferenciada la constituía el miedo a los efectos adversos: 39%, y el sentimiento de vergüenza relacionado con los procedimientos: 30%. Un 33% de los encuestados tenían hecho un método de rastreo, mayoritariamente de sangre oculta (27), sigmoideoscopía (11) y colonoscopía (20). Una mayoría afirmó que "se haría el procedimiento si el médico se lo recomendara" (95%), o "no se lo haría excepto que su médico se lo aconseje" (87%). Contestar afirmativamente que "los médicos hacen lo mejor para los pacientes" se asoció con haberse hecho un método de rastreo de CCR, OR 1.55 (IC 95%: 1.02-2.37) p: 0.04. El grupo de individuos estudiado parece bien predispuesto para el rastreo del CCR, la recomendación médica sería aquí un determinante prominente para ponerlo en práctica.

There is strong evidence favoring colorectal cancer screening. Preliminary data suggests that it is not included in routine practice with the adequate frequency. We intended to recognize in a Health Care System (HCS) that provides the needed resources, the facilitators and barriers related with the implementation of this preventive practice, how many individuals have carried out one procedure and what this preventive activity predicts. A telephone survey was administered to a sample of affiliates from an HCS that serves employees of the University of Buenos Aires; 132 completed the questionnaire (70% response rate). Facilitators obtained an affirmative response in a 64 to 97%, and barriers from 11 to 27%. In the latter category a special subgroup (39%) was afraid of adverse events, and there was a feeling of embarrassment in others (30%); 33% of respondents had carried out a screening procedure, mainly FOBT 27, sigmoidoscopy 11 and colonoscopy 20. A majority (95%) stated that they "would do the procedure if doctors recommend it", or "not do it unless my doctor advises to do it" (87%). Answering affirmatively that "physicians will do the best for their patients" was associated with having had a CRC screening test, OR 1.55 (95% CI: 1.02-2.37) p: 0.04. Studied individuals showed good predisposition for colorectal cancer screening, but to put it into practice, medical advice seems to be a prominent determinant.

The Gonyautoxin 2/3 epimers reduces anal tone when injected in the anal sphincter of healthy adults

The primary clinical symptom of Paralytic Shellfish Poisoning is acute paralytic illness produced by paralyzing toxins. Paralytic shellfish poison is formed by a mixture of phycotoxins and their toxicity is due to its reversible binding to a receptor site on the voltage-gated sodium channel on excitable cells, thus blocking neuronal transmission. We studied the effect of the gonyautoxin 2/3 epimers by local infiltration in the anal internal sphincter of healthy voluntary adults in order to reduce anal tone. The toxin was injected after prior clinical evaluation, anoscopy and anorectal manometry. Post injection clinical examination, electromyography and anorectal manometry were performed. Resting and voluntary contraction pressures were measured and the anorectal inhibitory and anocortical reflexes were tested by manometry. Blood and urine samples were obtained from each participant, and hemogram, basic metabolic panel, and urinalysis were done both before and one week after the injection. This study shows, for the first time, that gonyautoxin 2/3 reduces the anal tone by relaxing the anal sphincters in 100 % of the participants. Manometric recordings showed a significant decrease in anal maximal voluntary contraction pressure after the toxin injection, dropping to 55.2 ± 6.2 % and 47.0 ± 6.8 % (Mean Value ± Std.Dev.) of the baseline values at 2 minutes and at 24 hours respectively after the injection. Post-injection electromyography showed that activity of the muscle was abolished. We conclude that local administration of gonyautoxin 2/3 to the anal sphincter produces immediate relaxation and a statistically significant decrease in the anal tone (p <0.001)..