Background: Psychiatric problems, including bipolar affective disorder (BD) and schizophrenia, are common in mitochondrial diseases (MD) and frequently precede the diagnosis of mitochondrial dysfunction. However, they are rarely the only persistent manifestation of a MD and they are usually associated with other neurological or non-neurological features.
Case report: Here, we describe an Italian family with multiple deletions of mtDNA in muscle, in which BD, schizophrenia, and depression recurred over several generations in the absence of other major signs of mitochondrial dysfunction.
Conclusion: In patients with positive family history of psychiatric problems, the possibility of MD should be kept in mind, even in absence of other canonical features of mitochondrial encephalomyopathies.