Pyruvate dehydrogenase-E1α deficiency presenting as recurrent acute proximal muscle weakness of upper and lower extremities in an 8-year-old boy.

The mitochondrial pyruvate dehydrogenase enzyme complex (PDHC) plays an important role in aerobic energy metabolism and acid-base equilibrium. PDHC contains of 5 enzymes, 3 catalytic (E1, E2, E3) and 2 regulatory, as well as 3 cofactors and an additional protein (E3-binding protein) encoded by nuclear genes. The clinical presentation of PDHC deficiency ranges from fatal neonatal lactic acidosis to chronic neurologic dysfunction without lactic acidosis. Paroxysmal neurologic problems such as intermittent ataxia, episodic weakness, exercise-induced dystonia and recurrent demyelination may also be seen although they are rare. Here, we present an 8-year-old boy complaining of acute proximal muscle weakness of upper and lower extremities with normal mental status. He had a history of Guillain-Barré-like syndrome at the age of 2 years. Electrophysiologic studies showed sensorial polyneuropathy findings in the first attack and sensorimotor axonal polyneuropathy findings in the last attack. The genetic analysis revealed a previously reported hemizygote novel mutation of the PDHA1 gene (p.A353T/c.1057G > A), which encodes the E1α subunit of PDHC. Thiamine was ordered (15 mg/kg/day), dietary carbohydrates were restricted and clinical findings improved in a few weeks. This rare phenotype of PDHC deficiency is discussed.

Positive impact of levetiracetam on emotional learning and memory in naive mice.

AIMS: The effect of an antiepileptic drug on cognitive function is of primary importance with respect to the patient's quality of life. Levetiracetam (LEV) is a novel antiepileptic drug used to treat epilepsy, but its effects on spatial and emotional learning and memory are not yet well understood. The goal of our study was to establish the effects of LEV (17 and 54 mg/kg, intraperitoneally (IP)) on spatial memory retrieval in the Morris water maze test and on acquisition and memory formation in the passive avoidance (PA) test in naive mice. MAIN METHODS: The subjects were adult male BALB/c mice. Spatial learning and memory was established with the Morris water maze (MWM) test. The 'time spent in escape platforms quadrant' and the 'distance to platform' analyses were measured using a video tracking system to determine spatial memory function. Emotional learning and memory were determined with a one-trial, step-through passive avoidance test. KEY FINDINGS: In the MWM test, LEV (17 and 54 mg/kg) neither affected the time spent in the target quadrant nor altered the distance to platform. Moreover, LEV had no effect on swim speed. In the PA task, LEV (17 and 54 mg/kg) significantly prolonged retention latency. SIGNIFICANCE: Our results indicate that LEV did not alter spatial memory retrieval in the MWM test, but it did show some ameliorating effects on acquisition and memory formation in the PA test in naive mice.