Guillain Barre syndrome; Hypercapnic respiratory failure; Abdominal distension; tingling sensation of both hands and feet; acute demyelinating polyneuropathy; diminished motor strength in upper (3/5) and lower extremities (2/5); Areflexia; Ataxia; Generalized weakness; Respiratory muscle weakness; Dysphagia; This case was reported in a literature article and described the occurrence of guillain barre syndrome in a 67-year-old male patient who received Flu unspecified (Flu vaccine) for prophylaxis.   The patient's past medical history included hypertension, hyperlipidemia, emphysema and gastroesophageal reflux disease.   On an unknown date, the patient received Flu vaccine at an unknown dose. On an unknown date, 13 days after receiving Flu vaccine, the patient experienced guillain barre syndrome (serious criteria hospitalization and GSK medically significant), hypercapnic respiratory failure (serious criteria hospitalization and GSK medically significant), abdominal distension (serious criteria hospitalization), tingling feet/hands (serious criteria hospitalization), demyelinating polyneuropathy (serious criteria GSK medically significant), muscle weakness, areflexia, ataxia, weakness generalized, respiratory muscle weakness and dysphagia. The patient was treated with immunoglobulins nos (Ivig). On an unknown date, the outcome of the guillain barre syndrome, hypercapnic respiratory failure, abdominal distension, tingling feet/hands, demyelinating polyneuropathy, muscle weakness, areflexia, ataxia, weakness generalized, respiratory muscle weakness and dysphagia were recovering/resolving.   The reporter considered the guillain barre syndrome, hypercapnic respiratory failure, abdominal distension, tingling feet/hands, demyelinating polyneuropathy, muscle weakness, areflexia, ataxia, weakness generalized, respiratory muscle weakness and dysphagia to be related to Flu vaccine.  Additional details were provided as follows: This case was reported in a literature article and described the Guillain-Barre syndrome in a 67-year-old male patient, who was vaccinated with unspecified influenza vaccine (manufacturer unknown) for prophylaxis. The patient had past history of hypertension, hyperlipidemia, emphysema, and gastroesophageal reflux disease. The patient had previously denied recent respiratory or gastrointestinal infections, surgery, trauma, human immunodeficiency virus (HIV), or constitutional symptoms. No information on patient's family history or concomitant medication was provided. On an unspecified date, the patient received unspecified influenza vaccine (administration route and site unspecified, dosage unknown; batch number not provided). The age of vaccination was not provided but it could be 66 years or 67 years. On an unspecified date, an unknown period after the vaccination, the patient experienced abdominal distention and tingling sensation of both hands and feet. On an unspecified date, one day after the event onset and two weeks after the vaccination, the patient presented with pre-existing complaints and was subsequently hospitalized. Initial physical examination was remarkable for diminished motor strength in upper (3/5) and lower extremities (2/5) accompanied by areflexia. During hospitalization his condition worsened with subsequent development of ataxia as well as generalized weakness. Thirty-six hours after the admission, the patient developed respiratory muscle weakness with worsening negative inspiratory force (NIF) and subsequent hypercapnic respiratory failure requiring endotracheal intubation. Laboratory evaluation was unremarkable and head computed tomography (CT) scan did not suggest acute intracranial event. Further studies, including cerebrospinal fluid (CSF) analysis, failed to reveal albuminocytologic dissociation or any acute infectious process. An electromyography to evaluate for polyneuropathy revealed delayed distal latencies, decreased velocity, and absent F waves suggestive of an acute demyelinating polyneuropathy. The patient was diagnosed to Guillain-Barre syndrome. Despite receiving intravenous immunoglobulins (IVIGs) for 5 days the patient was a failure to wean from mechanical ventilation and a tracheostomy was performed, along with a percutaneous endoscopic gastrostomy due to dysphagia. As a result, two additional courses of IVIGs and one course of plasmapheresis were administered which led to weaning of mechanical ventilation and improvement of motor function. The patient was discharged on physical rehabilitation. This case has been considered as serious due to hospitalization. The author commented, "The influenza vaccine is recommended annually for every patient older than 6 months. Reported side effects include soreness on injection site, nausea, headache, fever, myalgia, and rarely, Guillain-Barre Syndrome (GBS). GBS is the most common cause of acute flaccid paralysis, with annual incidence of 1.2-3 cases per 100,000 habitants. Even though there is low risk for the development of GBS, it is important to recognize that, annually, one to two cases of GBS are reported per million of patients vaccinated with influenza. The only risk factor identified was the administration of influenza vaccination two weeks prior to admission. GBS is recognized as an acute immune-mediated polyneuropathy, usually provoked by a preceding infection. Although rare, development of GBS is a potential complication of the Influenza vaccine."      Lab Comments: Lab test done on an unknown date. Initial physical examination was remarkable for diminished motor strength in upper (3/5) and lower extremities (2/5) accompanied by areflexia. The patient developed respiratory muscle weakness with worsening negative inspiratory force (NIF). Laboratory evaluation was unremarkable and head computed tomography (CT) scan did not suggest acute intracranial event. Further studies, including cerebrospinal fluid (CSF) analysis, failed to reveal albuminocytologic dissociation or any acute infectious process. An electromyography to evaluate for polyneuropathy revealed delayed distal latencies, decreased velocity, and absent F waves suggestive of an acute demyelinating polyneuropathy.