The description of the clinical case refers to analysis of the dynamics of psychopathological picture in a patient hospitalized in the Department of Adolescence Psychiatry in the context of spontaneous creation and also creation inspired during individual art therapy classes. The process of re-diagnosis – from bipolar affective disorder to schizoaffective disorders – was initiated within the discussion about the patient’s artistic works. Her artistic works during a consecutive depressive phase without psychotic symptoms exhibited: considerable disorganization features, symbols, figure deformation, contaminations, space divisions unjustified by the contents, and unstable perspectives, which for a few months preceded the development of full-symptom psychosis exhibiting all criteria of schizophrenia. The 18-year-old patient, ill for a year, was first treated for mania in the course of bipolar affective disease. She exhibited raised spirits and drive, fast train of thought; she uttered delusions of grandeur and missionary delusions; she shortened the distance, reported “enhanced sensual perception” and “increased awareness”, and wanted to “bring beauty to the world”. She said that she had experienced swinging mood for a long time – from “depression” with sadness, exhaustion, anhedonia, hypersomnia, considerably decreased activity, suicidal thoughts to states of “euphoria” and “hyperactivity”. Soon after being discharged from hospital the patient discontinued medication and several months later was admitted to the ward again, with symptoms of depression episode and suicidal tendencies. During this hospitalization the patient jawas offered to participate in individual art therapy classes because of her spontaneous artistic creativity (including painting on walls) and to refuse to take part in group classes. The therapeutic team to which the art therapist belonged determined the following objectives of art therapy: diagnostic, communicative, integrative and cathartic. An additional role of the art therapist was to initiate changes in the patient’s functioning and individual creative process.