Acute Hepatic Porphyria Presenting as Guillain-Barré Syndrome: Importance of Early Recognition and Screening

Acute hepatic porphyria (HP) often presents with recurrent neurovisceral symptoms in young adults, mimicking more common neurological conditions such as Guillain-Barré Syndrome (GBS) and posing significant diagnostic challenges. We report a case of a 25-year-old male who presented with progressive weakness of all 4 limbs over 4 days, culminating in respiratory paralysis requiring mechanical ventilation. Neurological examination revealed acute flaccid paralysis with areflexia, and nerve conduction studies showed acute motor axonal neuropathy, initially supporting a diagnosis of GBS. However, the patient's young post-pubertal age, onset in the upper limb with proximal weakness, pure motor axonal neuropathy, and presence of hyponatremia due to the syndrome of inappropriate antidiuresis raised suspicion of acute HP. Screening with qualitative urine porphobilinogen testing, followed by quantitative confirmation, diagnosed acute HP. The patient was treated with intravenous dextrose in the absence of hemin, resulting in gradual clinical improvement. This case underscores the importance of distinguishing acute HP from GBS and the need for early recognition and screening to initiate life-saving therapy.