RESUMEN
Superior Mesenteric Artery Syndrome (SMAS) resulting from proximal partial small bowel obstruction is one of possible causes of acute gastric dilatation (AGD). A child with refractory demyelinating Guillain-Barré syndrome which received 5 times IVIG and consequently 5 times plasmapheresis intubated until 59th day of admission. Because of complicated treatment and cardiopulmonary resuscitation (CPR) nutrition was completely neglected which lead to severe SMAS because of weight loss. Gradual advancements of continuous enteral and parenteral nutrition improved patient's symptoms significantly. Hypophosphatemia complicated the weaning from ventilator which after nutrition therapy resolved and patient extubated. Present case is the first report of pediatric demyelinating GBS suspected to SMAS.