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La deficiencia de vitamina A, a menudo asociada con nictalopia, ha sido descrita en pacientes con malabsorción como resultado de cirugía de bypass intestinal y, en los últimos años, de cirugía bariátrica. Investigadores del Cullen Eye Institute del Baylor Collage de Houston (Estados Unidos) sugieren que debe sospecharse la deficiencia de esta vitamina en pacientes con pérdida de visión idiopática e historia de cirugía intestinal, de forma independiente, además, del tiempo transcurrido desde la intervención.
Así lo recogen en un estudio, aparecido en “British Journal of Ophthalmology”, en el que de cuatro pacientes con vitamina A tres habían sido intervenidos de cirugía intestinal más de 18 años antes del desarrollo de síntomas visuales.
British Journal of Ophthalmology 2006;90:955-956