Guillain-Barré Syndrome (AIDP Variant) Temporally Associated With Purified Vero Cell Rabies Vaccination (Rabivax-S) in a 23-Year-Old Male: A Case Report

Background: Guillain-Barré Syndrome (GBS), particularly the Acute Inflammatory Demyelinating Polyneuropathy (AIDP) variant, is a rare but serious immune-mediated polyradiculoneuropathy. While most cases follow infections, vaccination is a recognized, albeit uncommon, trigger. This report describes a case of AIDP following administration of purified Vero cell rabies vaccine (PVRV, Rabivax-S) and tetanus toxoid as post-exposure prophylaxis, highlighting the need for continued pharmacovigilance with modern cell-culture rabies vaccines in rabies-endemic regions. Case Presentation: A previously healthy 23-year-old male developed acute ascending flaccid quadriparesis 11 days after receiving the first three doses of purified Vero cell rabies vaccine (Rabivax-S) along with tetanus toxoid following a monkey bite. He presented with severe symmetric weakness (Medical Research Council grade 2/5 in upper limbs, 1/5 in lower limbs), generalized hypotonia, and areflexia, without autonomic instability or respiratory compromise (diaphragmatic excursion ~4 cm). Nerve conduction studies performed on day 6 of weakness revealed markedly reduced compound muscle action potential amplitudes, prolonged distal motor latencies, severely slowed conduction velocities, and conduction block — most strikingly a 99% CMAP amplitude reduction in the right peroneal nerve — with preserved sensory responses, fulfilling electrodiagnostic criteria for AIDP. Cerebrospinal fluid analysis revealed albuminocytologic dissociation (protein 231 mg/dL, 4 cells/µL). The patient received intravenous immunoglobulin (0.4 g/kg/day for 5 days), supportive care, and physiotherapy. After three weeks of hospitalization and six months of rehabilitation, he achieved partial recovery with residual moderate weakness. Conclusion: This case illustrates a temporal association between purified Vero cell rabies vaccination (administered concurrently with tetanus toxoid) and AIDP. While causality cannot be proven, clinicians should maintain a high index of suspicion for GBS in patients developing acute flaccid paralysis after rabies post-exposure prophylaxis. Early nerve conduction studies and prompt immunomodulatory therapy are essential. The overwhelming life-saving benefits of rabies vaccination continue to far outweigh this rare potential risk.