Guillain-Barre syndrome; This literature-non-study case was reported in a literature article and describes the occurrence of GUILLAIN-BARRE SYNDROME (Guillain-Barre syndrome) in a 38-year-old male patient who received mRNA-1273 (Moderna COVID-19 Vaccine) for COVID-19 prophylaxis.        The patient's past medical history included Lung transplant (Double lung transplant).    On an unknown date, the patient received third dose of mRNA-1273 (Moderna COVID-19 Vaccine) (unknown route) 1 dosage form. On an unknown date,  after starting mRNA-1273 (Moderna COVID-19 Vaccine), the patient experienced GUILLAIN-BARRE SYNDROME (Guillain-Barre syndrome) (seriousness criterion medically significant). The patient was treated with IMMUNOGLOBULINS NOS (IMMUNOGLOBULIN I.V) (intravenous) at an unspecified dose and frequency; IMMUNOGLOBULINS NOS (IMMUNOGLOBULIN I.V) (intravenous) at an unspecified dose and frequency and Physical therapy for Guillain-Barre syndrome. At the time of the report, GUILLAIN-BARRE SYNDROME (Guillain-Barre syndrome) was resolving.      DIAGNOSTIC RESULTS (normal ranges are provided in parenthesis if available): On an unknown date, CSF oligoclonal band: Negative. On an unknown date, Electromyogram: Showed evidence of acute inflammatory demyelinating polyneuropathy, confirming the GBS diagnosis. On an unknown date, Lumbar puncture: Revealed albuminocytologic dissociation with a cell count of 1/uL. On an unknown date, Magnetic resonance imaging spinal: Showed no evidence of nerve root enhancement. On an unknown date, Neurological examination: Showed symmetric ascending weakness of lower extremities that was worse distally, reduced hand-grip strength, and areflexia. On an unknown date, Protein total: 113 mg/dl high.     For mRNA-1273 (Moderna COVID-19 Vaccine) (Unknown), the reporter did not provide any causality assessments.   Concomitant medications were not specified.  Patient was on standard unspecified 3-drug immunosuppression presented to clinic complaining of back pain 2 weeks after receiving a third dose of vaccination. Patient pain was treated with analgesics, however, a week later patient presented to the Emergency Department (ED) with worsening back pain, myalgias, and lower extremity weakness. Neurology was consulted.  Patient underwent an extensive work-up including screening serologies for vasculitis and myasthenia gravis and blood tests for B12, folate, and creatinine kinase (CK) levels. Viral and bacterial infections were ruled out. Autoimmune and paraneoplastic panels were negative. Patient was diagnosed with Guillain-Barre Syndrome and completed a 5-day IVIG course which led to transient symptomatic improvement.  Four weeks later, patient reported to the ED in a wheelchair after multiple falls and an inability to stand or walk. An additional 2-day IVIG course and intensive outpatient physical therapy led to neurologic improvement.   Although current data did not suggest an increased risk of GBS after mRNA COVID-19 vaccines, GBS should be considered in lung transplant recipients who develop symmetric motor and sensory deficits after vaccination.  Company Comment: This is a literature non-study case concerning a 38-year-old male patient with a history of double lung transplant (on standard unspecified 3-drug immunosuppression), who experienced the serious (due to medically significant) unexpected, AESI Guillain-Barre syndrome (GBS). The event occurred approximately 2 weeks after the third dose of mRNA-1273 vaccine. Patient complained of back pain (treated with analgesics) which worsened and added myalgias, and lower extremity weakness. He underwent an extensive work-up including screening serologies for vasculitis, infections and myasthenia gravis. A lumbar puncture revealed albumin cytologic dissociation with a high protein level of 113 mg/dL and cell count of 1/uL. Autoimmune and paraneoplastic panels as well as oligoclonal bands were negative. He was diagnosed with GBS and completed a 5 days IVIG course which led to transient symptomatic improvement. Four weeks later, symptoms progressed, and he had to use a wheel chair. Electromyography showed evidence of acute inflammatory demyelinating polyneuropathy, confirming the GBS diagnosis.  The outcome of the event was reported as recovering at the time of this report. The  benefit-risk relationship of mRNA-1273 vaccine is not affected by this report.; Sender's Comments: This is a literature non-study case concerning a 38-year-old male patient with a history of double lung transplant (on standard unspecified 3-drug immunosuppression), who experienced the serious (due to medically significant) unexpected, AESI Guillain-Barre syndrome (GBS). The event occurred approximately 2 weeks after the third dose of mRNA-1273 vaccine. Patient complained of back pain (treated with analgesics) which worsened and added myalgias, and lower extremity weakness. He underwent an extensive work-up including screening serologies for vasculitis, infections and myasthenia gravis. A lumbar puncture revealed albumin cytologic dissociation with a high protein level of 113 mg/dL and cell count of 1/uL. Autoimmune and paraneoplastic panels as well as oligoclonal bands were negative. He was diagnosed with GBS and completed a 5 days IVIG course which led to transient symptomatic improvement. Four weeks later, symptoms progressed, and he had to use a wheel chair. Electromyography showed evidence of acute inflammatory demyelinating polyneuropathy, confirming the GBS diagnosis.  The outcome of the event was reported as recovering at the time of this report. The  benefit-risk relationship of mRNA-1273 vaccine is not affected by this report.