Hyperreflexia and Preserved Reflexes in Pediatric Guillain-Barré Syndrome: A Case Report and Literature Review

Abstract

Guillain-Barré syndrome (GBS) is the most prevalent cause of acute flaccid paralysis, often following an antecedent illness such as upper respiratory infections. Acute motor axonal neuropathy (AMAN), a subtype of GBS, predominantly affects motor axons, resulting in significant motor impairment, and is frequently associated with Campylobacter jejuni infection. We present a case of a three-year-old female patient who developed AMAN, a subtype of Guillain-Barré Syndrome (GBS). Approximately 10 days prior to admission, she had a history of fever, sore throat, and cough, which slightly improved for one day following a five-day course of antibiotics. However, her condition then worsened, and she began experiencing vomiting of gastric contents and occasional sputum production. Despite initial improvement, her condition deteriorated, leading to decreased muscle strength, exaggerated reflexes, and progressive respiratory failure. Neurophysiological studies, including nerve conduction studies (NCSs) and imaging, were consistent with AMAN. The patient was treated with intravenous immunoglobulin (IVIG) therapy and required endotracheal intubation for respiratory support. Over the course of her hospitalization, her neurological status improved significantly, and by day 9, she was able to walk with assistance, marking a successful recovery. This case highlights the importance of early diagnosis and intervention in managing GBS in pediatric patients, particularly in the context of atypical presentations, including hyperreflexia.

Keywords: acute motor axonal neuropathy; aman; atypical presentation; guillain-barré syndrome; hyperreflexia.

Figure 1. Brain MRI of the patient on admission

Axial FLAIR brain MRI showing multiple nonspecific periventricular white matter hyperintense foci (red arrows). No diffusion restriction or abnormal enhancement is seen. The absence of central nervous system lesions helps exclude differential diagnoses such as ADEM, supporting a peripheral etiology consistent with the AMAN subtype of GBS. FLAIR: fluid-attenuated inversion recovery, MRI: magnetic resonance imaging, ADEM: acute disseminated encephalomyelitis, AMAN: acute motor axonal neuropathy, GBS: Guillain-Barré syndrome

Figure 2. Spinal MRI of the patient on admission

T1-weighted MRI of the lumbar spine demonstrating smooth thickening and enhancement of spinal nerve roots within the cauda equina and conus medullaris region (red arrows) in sagittal view, findings consistent with Guillain-Barré syndrome. MRI: magnetic resonance imaging