Rare Abdominal Pain Onset in Guillain-Barré Syndrome: A Case Report of Acute Motor Sensory Axonal Neuropathy

BACKGROUND Guillain-Barre syndrome (GBS) typically presents with ascending weakness and sensory disturbances. However, initial symptoms like abdominal pain are rare and can make diagnosis more challenging, as this is not a common feature of GBS. This diagnostic delay can be particularly significant in severe GBS subtypes like acute motor and sensory axonal neuropathy (AMSAN), with only a few reported cases presenting in this atypical manner. CASE REPORT A 42-year-old man experienced 3 days of persistent abdominal pain that progressively disrupted his normal activities. Soon after, he developed weakness and loss of sensation, beginning in his lower limbs and eventually spreading to the upper limbs. His condition rapidly deteriorated, resulting in respiratory failure that required intubation. Upon examination, muscle weakness and sensory loss were noted, leading to a diagnosis of AMSAN. This was confirmed by nerve conduction studies, MRI, and cerebrospinal fluid analysis. The patient initially received intravenous immunoglobulin (IVIG) but showed minimal improvement after 8 days. He then underwent plasma exchange, consisting of 5 treatment cycles. After 64 days in the hospital, including 39 days in the intensive care unit (ICU), he was discharged and able to walk with assistance. CONCLUSIONS This case highlights the importance of recognizing the atypical presentations of GBS, particularly the AMSAN subtype. The patient's initial presentation of severe abdominal pain, followed by rapid neurological deterioration, underscores the need for clinicians to maintain a high index of suspicion for GBS even when symptoms diverge from the classic ascending paralysis.