Abstract
We describe a case of mitochondrial myopathy, encephalopathy, lactic acidosis and stroke-like episodes (MELAS) [1] with psychiatric symptoms successfully treated with coenzyme Q10 (CoQ) [2].
A 48-year-old right-handed woman of short stature and small build (142.2 cm, and 37.6 kg) experienced a sudden onset of stroke-like episode with symptoms such as dropping things and experiencing paralysis and pain in her left hand while shopping. Within 1 month, her paralysis and pain abated, but she started to show aggression toward her husband.
Five months later, the patient developed sudden cognitive deterioration and memory disturbance. Subsequently, she experienced a sudden retrogression of hearing loss. Gradually, paranoid ideation and the aggressive attitude toward her husband became more severe: she believed that her husband had stolen her bag. Three days later, she was hospitalised in our psychiatric ward.
The patient had a history of hearing loss, beginning when she was 30 years old, and diabetes mellitus, for which she had taken insulin therapy (30 U/day), beginning at age 40. Her father, her mother and her younger sister had a history of hearing loss.
Muscle atrophy or limb weakness were not found on examination. Her electroencephalogram (EEG) was normal. T1-weighted magnetic resonance imaging (MRI) hyperintensities of the bilateral temporo-parietal lobe, and cerebral calcifications at the heads of the bilateral caudate nucleus were detected. These areas of hyperintensity predominated in the cortex and were not limited to a specific vascular territory. Single photon emission computed tomography (SPECT, 99mTc-ECD) revealed right temporo-parietal hypoperfusion and left temporo-basal hypoperfusion. No increase of lactic acid or pyruvate was detected by blood test. On analysis of the cerebrospinal fluid (CSF), a slightly increased pyruvate level of 204.48 μmol/L (normal range, 42.03–85.20 μmol/L) and an increased lactic acid level of 4.77 mmol/L (normal range, 0.97–1.50 mmol/L) were disclosed. An adenine (A) to guanine (G) mitochondrial DNA (mtDNA) point mutation at nucleotide 3243 coding for the transfer ribonucleic acid (tRNALeu(UUR)) gene [3] was detected. A muscle biopsy specimen to determine the ragged red fibers was not obtained.
A regimen of CoQ was subsequently initiated: 30 mg/day increased to 70 mg/day. The patient was seen in follow up 3 months after her last stroke-like episode and reported no new stroke-like episodes. She had improved auditory comprehension and fluency of speech. The delusions of persecution as well as the suspicious and aggressive attitude toward her husband had also improved. Eight weeks after CoQ treatment started, she was discharged and was able to move back to her home and live with her family. Along with the improvement of psychiatric symptoms, CSF lactic acid levels decreased down to 3.57 mmol/L (6 weeks after CoQ treatment was started).
In the present case, the CSF lactic acid levels decreased after CoQ treatment was started along with the improvement in psychiatric symptoms such as delusions of persecution. In addition, no antipsychotic drug was used during the therapy. Thus, the patient's psychiatric symptoms may be due to MELAS, at least in part, and these symptoms might have responded to CoQ.