Recurrent posterior reversible encephalopathy syndrome in mitochondrial disorder

Objectives. Recurrent posterior reversible encephalopathy syndrome (PRES) has not been reported in association with multi-system mitochondrial disorder (MID). Case report. In a 60-year-old HIV-negative, Caucasian female with short stature, double vision, struma, memory impairment, chronic renal failure requiring hemodialysis, seizures, intermittent atrial fibrillation, arterial hypertension, hyperlipidemia, anemia, hypacusis, tinnitus, and a daughter with multiple sclerosis, short stature and hypothyroidism, another daughter with schizophrenia, and a son who died from encephalopathy at age 3 months, an MID was suspected. At age 53 years, she experienced sudden, transient blindness for 2 days bilaterally during an episode of high blood pressure with complete recovery within 2 weeks. At age 60 years, a similar episode occurred. Four weeks later, she experienced a third PRES episode with high blood pressure, seizures, impaired consciousness and reversible blindness for 2 days. MRI at the second episode was indicative of a PRES, and MRI at the third episode additionally revealed occipital bleedings, acute embolic stroke and features indicating PRES. Conclusions. This case indicates that MID may be associated with recurrent PRES, triggered by recurrent episodes of high blood pressure. Whether high blood pressure was a manifestation of the MID or related to other causes remains speculative. PRES does not seem to be a primary but is rather a secondary manifestation of an MID.