Epilepsy and trimethylaminuria: A new case report and literature review

Trimethylaminuria is a metabolic disorder characterized by the excessive excretion of trimethylamine in bodily secretions, which confers a very unpleasant odour resembling that of dead fish. Literature reports only two cases affected by trimethylaminuria and epilepsy. We describe a third patient who, from the age of seven, was affected by temporal focal seizures with nocturnal episodes of nausea, vomiting, anxiety and autonomic activation followed by headache. EEG showed focal paroxysmal abnormalities prevailing on the right temporo-parieto-occipital regions. We began administering levetiracetam and seizures stopped. Our patient also showed learning disabilities despite a normal intelligence quotient (IQ), while another described patient had an IQ varying from borderline to mild mental retardation. We discuss the association between trimethylaminuria and epilepsy, and formulate some hypotheses on the relationship between trimethylamine convulsive effect and the anticonvulsive role of levetiracetam.