Acute Intermittent Porphyria: Flaccid Quadriplegia and Encephalopathy due to Posterior Reversible Encephalopathy Syndrome (PRES)

Abstract

A deficiency of the enzyme HMB Hydroxymethylbilane synthase function, also known as porphobilinogen deaminase, leads to the emergence of acute intermittent porphyria (AIP). AIP is an uncommon form of hepatic porphyria inherited in an autosomal dominant fashion. We present a case involving a young girl who experienced a sudden onset of quadriparesis, a severe neurological condition that necessitated ventilator support due to respiratory distress. Her condition was consistent with motor axonal neuropathy, which is a characteristic feature of Acute Intermittent Porphyria (AIP). During her last hospital admission, she developed new-onset generalized tonic-clonic seizures, and MRI findings at that time indicated the presence of hyperintense lesions in the posterior parietal region, likely attributed to Posterior Reversible Encephalopathy Syndrome (PRES). To manage her symptoms, she received Dextrose saline due to the elevated levels of urinary porphobilinogen. This case underscores the significance of recognizing two alarming complications associated with porphyria, namely PRES and acute motor axonal neuropathy. Despite an appropriate and timely diagnosis, our efforts were unsuccessful in averting these complications. The unavailability of Hematin, a vital treatment for acute porphyria attacks, was the primary reason for her unfortunate demise.