In the clinical practice we encounter different clinical situations that require precise differential diagnosis and special treatment. This poster reviews the diagnosis and pharmacotherapy of two cases that points out how likely is to confuse the diagnosis of two apparently different pathologies, as are bipolar disorder and frontotemporal dementia. We study and compare two cases that were hospitalised in the psychiatric ward of Sant Joan's Hospital. Following their treatment and evolution. The first case is a 75-years-old man that presented behavioural changes, hypomania, and insomnia without previous known psychiatric history other than alcoholism. The family explained a history of episodes of mood changes going from depression to mania, compatible with a bipolar diagnosis never diagnosed, and the neuropsychological exam that was performed did not show any cognitive impairment finally receiving a diagnosis of bipolar disorder after the good response to the lithium treatment. In the second case we have a 58-years-old man with behavioural disturbances and mood fluctuation that changes from short periods of hypomania with disinhibition and insomnia to a predominance of hypothymia, apathy and self-care negligence, which received at the beginning a diagnosis of bipolar disorder and that after the proper complementary tests was shown to be a frontotemporal dementia.

When facing behavioural and mood changes in advance age in the absence of psychiatric history we should take into account the considerable percentage of patients with a final diagnosis of frontotemporal dementia that received previously a mistaken diagnosis of bipolar disorder and vice versa.

The authors have not supplied their declaration of competing interest.