GBS, most consistent with the ABPp variant; acute bulbar palsy; cranial neuropathies; worsening facial weakness/ bilateral upper and lower facial weakness, left worse than right; difficulty walking/displayed a staggering, cautious gait while walking.; hoarse cry/ cried; bilateral facial palsy/left face appeared flat and emotionless with the left eye slightly open without any tears, while the right face was creased with the right eye closed and tears coming out; stopped talking/nonverbal but hummed with a soft voice; gasping to breathe; increased difficulty with eating and drinking; dysphagia/increased difficulty with drinking; Unable to walk without assistance; inspiratory stridor; Reflexes were absent/ Areflexia; dysmetria bilaterally when attempting to grab small items with each hand; Dysphonia; Ataxia/ Ataxic gait; This case was reported in a literature article and described the occurrence of guillain barre syndrome in a 3-year-old female patient who received Flu unspecified (Influenza vaccine) for prophylaxis.   On an unknown date, the patient received Influenza vaccine. On an unknown date, several hours after receiving Influenza vaccine, the patient experienced guillain barre syndrome (serious criteria hospitalization and GSK medically significant), bulbar palsy (serious criteria hospitalization and GSK medically significant), cranial neuropathy (serious criteria hospitalization), facial weakness (serious criteria hospitalization), walking difficulty (serious criteria hospitalization), crying abnormal (serious criteria hospitalization), facial palsy (serious criteria hospitalization and GSK medically significant), speech disorder (serious criteria hospitalization), gasping (serious criteria hospitalization), eating disorder (serious criteria hospitalization), dysphagia (serious criteria hospitalization), unable to walk (serious criteria hospitalization), stridor inspiratory (serious criteria hospitalization), absent reflex (serious criteria hospitalization), dysmetria (serious criteria hospitalization and GSK medically significant), dysphonia (serious criteria hospitalization) and ataxia (serious criteria hospitalization). The patient was treated with acyclovir and immunoglobulins nos (Intravenous Immunoglobulin). On an unknown date, the outcome of the guillain barre syndrome, bulbar palsy, cranial neuropathy, facial weakness, walking difficulty, crying abnormal, facial palsy, speech disorder, gasping, eating disorder, dysphagia, unable to walk, stridor inspiratory, absent reflex, dysmetria, dysphonia and ataxia were recovered/resolved.   The reporter considered the guillain barre syndrome, bulbar palsy, cranial neuropathy, facial weakness, walking difficulty, crying abnormal, facial palsy, speech disorder, gasping, eating disorder, dysphagia, unable to walk, stridor inspiratory, absent reflex, dysmetria, dysphonia and ataxia to be related to Influenza vaccine.     Additional Information: GSK Receipt Date: 10-Aug-2022 Author's comment: The patient was normally developing right-handed and presented to the emergency department with worsening facial weakness and difficulty walking. The patient was in her usual state of health, with no known recent illnesses, until 5 days prior to presentation. A few hours after receiving her influenza vaccination, the mother noticed that, while the patient cried, her left face appeared flat and emotionless with the left eye slightly open without any tears, while the right face was creased with the right eye closed and tears coming out. The patient was prescribed acyclovir by her pediatrician on the next day for suspected Bell's palsy. Two days later, the patient stopped talking and appeared as if she was gasping to breathe. The patient was also had increased difficulty with eating and drinking and was no longer able to walk without assistance. At the time of her presentation, her lung exam was remarkable for inspiratory stridor. On neurologic exam, the patient was awake and followed commands. The patient was nonverbal but hummed with a soft voice. Her pupils were equal and reactive to light, and gaze was conjugate in all directions. The patient had bilateral upper and lower facial weakness, left worse than right. When the patient laughed, her right lower face moved slightly up, while the left lower face did not move, and the left nasolabial fold remained absent. The patient's strength was full throughout, and she responded to touch in all extremities. Reflexes were absent throughout. The patient had dysmetria bilaterally when attempting to grab small items with each hand. The patient stood without assistance but displayed a staggering, cautious gait while walking. Magnetic resonance imaging (MRI) of the brain with and without contrast revealed abnormal smooth enhancement of the bilateral oculomotor, trigeminal, facial, and vagus nerves. MRI of the entire spine obtained with and without contrast showed similar smooth enhancement of spinal nerve roots at many levels, most conspicuous in the cauda equina and cervicothoracic junction. Lumbar puncture with cerebrospinal fluid (CSF) studies showed white blood cell count of 19 cells/cm2 (normal 0-10) without red blood cells, glucose 81 mg/dL (normal 45-75), and protein 116 mg/dL (normal 15-45). Meningitis panel and CSF cultures were negative. Multiple sclerosis panel showed elevated CSF immunoglobulin G (IgG) with elevated IgG synthesis rate, without oligoclonal bands. Serum and CSF autoimmune encephalopathy panels were negative. Serum acute neuropathy panel was negative for IgM and IgG antibodies against GM1, GD1a, GD1b, GM2, GT1A, and GQ1b. The patient was diagnosed with Guillain-Barre syndrome (GBS), most consistent with the acute bulbar palsy plus (ABPp) variant. The patient received intravenous immunoglobulin 1 mg/kg daily for 2 days. The patient's respiratory status was monitored and without complication, and her symptoms steadily improved over the next 10 days. By hospital discharge, the patient appeared to smile with present bilateral nasolabial folds. Her cry was less hoarse, and she was able to eat soft foods. Reflexes remained absent throughout, and she continued to have mild ataxic gait requiring intermittent assistance. The patient was discharged to inpatient rehabilitation with ongoing physical, occupational, and speech therapy. On three-month follow-up, the patient was back to her normal self, with intact facial strength, fluent speech with normal pitch and no dysarthria, and normal reflexes. No ataxia was observed, as she was able to run, skip, and jump up and down without difficulty. This was the youngest patient in the literature to date who developed the acute bulbar palsy-plus (ABPp) variant of GBS. It was suspected that her influenza vaccine most likely contributed to her development of GBS, given her onset of symptoms just hours after vaccine administration and lack of other known risk factors. This short latency is unusual given that the risk for GBS is expected in the 8 to 21 day window after vaccinations. Additional supportive information: The article corresponding to this case is not available for regulatory submission due to copyright restriction.