Acute Porphyria Presenting as Epilepsia Partialis Continua
A 49-year-old right-handed man with a past medical history of Berger's disease presented to the emergency room on December 13, 2009, for a 1-min-long tonic-clonic seizure and increasing confusion over the past week. He was immediately started on acyclovir and phenytoin. The initial EEG, brain MRI and lumbar puncture were normal. Within 2 days, he developed continuous right hand myoclonic jerks compatible with epilepsia partialis continua (EPC). Repeat brain MRI performed 3 days after admission disclosed non-enhancing high T2 and FLAIR signal changes over the bilateral temporal lobes (fig. ). Brain PET revealed focal hypermetabolism over the bilateral frontal and temporal lobes, predominantly over the left side. Repeat EEG revealed left frontotemporal periodic lateralized epileptiform discharges (fig. ). A repeat lumbar puncture at day 3 was within normal limits. Bacteriological, viral serological (including herpes simplex virus PCR) workup, immunologic parameters as well as toxicology screen revealed no abnormal findings. While the confusion progressively waned, EPC persisted despite several antiepileptic drug trials (phenytoin, valproic acid, carbamazepine, clobazam, lamotrigine). A probable diagnosis of HPC was eventually made when urine coproporphyrins and fecal total porphyrins returned to twice the normal range (even when testing was made 9 days after admission while the patient was improving). These abnormal results could not be explained by other conditions which have previously been associated with secondary coproporphyrinurias such as abuse of toxic substances, liver diseases, malignancies, diverse hematological diseases, etc. []. Over the last 3 years, the patient has continued to present non-disabling EPC (manifesting only as very low-amplitude right hand myoclonic jerks) and has had a total of four tonic-clonic seizures in the context of alcohol consumption. He remains with mild memory problems and is currently treated with levetiracetam. On the last brain MRI (2 years after initial setting), T2 signal changes had decreased significantly (fig. ).