Guillain-Barré Syndrome Following SARS-CoV-2 Pneumonia in a Patient Receiving Adjuvant Chemotherapy for Gastric Cancer: A Case Report

Guillain-Barré Syndrome (GBS) is an acute, progressive inflammatory polyneuropathy characterized by muscle weakness and distal sensory deficits. In the context of SARS-CoV-2 infection, GBS most commonly presents as a sensorimotor variant, frequently associated with facial paralysis and a demyelinating electrophysiological pattern. We report the case of a 47-year-old female diagnosed with stage IIb (T3, N1, M0) gastric adenocarcinoma who underwent gastrectomy followed by five cycles of adjuvant chemotherapy. During the fifth cycle, she developed SARS-CoV-2-associated pneumonia involving 30% of lung parenchyma and required hospitalization. Following recovery and discharge, the patient experienced progressive lower limb weakness and sensory disturbances. Electro Neuro Myo Graphy (ENMG) demonstrated mixed sensory and motor nerve involvement in both upper and lower extremities predominantly on the left consistent with a combined axonal-demyelinating neuropathy.This case illustrates a rare occurrence of GBS in an immunocompromised individual recovering from COVID-19. It is hypothesized that SARSCoV-2 contributed to autoimmune activation via systemic inflammation and cytokine release, ultimately triggering GBS. Clinicians should maintain a high index of suspicion for post-infectious neuropathies such as GBS, particularly in oncology patients recovering from SARS-CoV-2 infection.