Diagnosing Organic Causes of Schizophrenia Spectrum Disorders: Findings from a One-Year Cohort of the Freiburg Diagnostic Protocol in Psychosis (FDPP)

Dominique Endres; Miriam Matysik; Bernd Feige; Nils Venhoff; Tina Schweizer; Maike Michel; Sophie Meixensberger; Kimon Runge; Simon J Maier; Kathrin Nickel; Karl Bechter; Horst Urbach; Katharina Domschke; Ludger Tebartz van Elst

doi:10.3390/diagnostics10090691

Diagnosing Organic Causes of Schizophrenia Spectrum Disorders: Findings from a One-Year Cohort of the Freiburg Diagnostic Protocol in Psychosis (FDPP)

Diagnostics (Basel). 2020 Sep 14;10(9):691. doi: 10.3390/diagnostics10090691.

Authors

Dominique Endres^{1

2}, Miriam Matysik^{1

2}, Bernd Feige^{1

2}, Nils Venhoff³, Tina Schweizer^{1

2}, Maike Michel², Sophie Meixensberger^{1

2}, Kimon Runge^{1

2}, Simon J Maier^{1

2}, Kathrin Nickel^{1

2}, Karl Bechter⁴, Horst Urbach⁵, Katharina Domschke^{2

6}, Ludger Tebartz van Elst^{1

2}

Affiliations

¹ Section for Experimental Neuropsychiatry, Department of Psychiatry and Psychotherapy, Medical Center-University of Freiburg, Faculty of Medicine, University of Freiburg, 79104 Freiburg, Germany.
² Department of Psychiatry and Psychotherapy, Medical Center-University of Freiburg, Faculty of Medicine, University of Freiburg, 79104 Freiburg, Germany.
³ Department of Rheumatology and Clinical Immunology, Medical Center-University of Freiburg, Faculty of Medicine, University of Freiburg, 79106 Freiburg, Germany.
⁴ Department for Psychiatry and Psychotherapy II, Ulm University, Bezirkskrankenhaus Günzburg, 89312 Günzburg, Germany.
⁵ Department of Neuroradiology, Medical Center-University of Freiburg, Faculty of Medicine, University of Freiburg, 79106 Freiburg, Germany.
⁶ Center for Basics in Neuromodulation, Faculty of Medicine, University of Freiburg, 79106 Freiburg, Germany.

Abstract

Introduction: Secondary schizophrenia spectrum disorders (SSDs) have clearly identifiable causes. The Department for Psychiatry and Psychotherapy at the University Hospital Freiburg has continued to expand its screening practices to clarify the organic causes of SSDs. This retrospective analysis was carried out to analyze whether a comprehensive organic diagnostic procedure could be informative in patients with SSDs. Methods and Participants: The "Freiburg Diagnostic Protocol in Psychosis" (FDPP) included basic laboratory analyses (e.g., thyroid hormones), metabolic markers, pathogens, vitamin status, different serological autoantibodies, rheumatic/immunological markers (e.g., complement factors), cerebrospinal fluid (CSF) basic and antineuronal antibody analyses, as well as cranial magnetic resonance imaging (cMRI) and electroencephalography (EEG). The findings of 76 consecutive patients with SSDs (55 with paranoid-hallucinatory; 14 with schizoaffective; 4 with hebephrenic; and 1 each with catatonic, acute polymorphic psychotic, and substance-induced psychotic syndromes) were analyzed. Results: Overall, vitamin and trace element deficiency was identified in 92%. Complement factor analyses detected reduced C3 levels in 11%. Immunological laboratory alterations were detected in 76%. CSF analysis revealed general alterations in 54% of the patients, mostly with signs of blood-brain barrier dysfunction. cMRI analyses showed chronic inflammatory lesions in 4%. Combination of EEG, cMRI, and CSF revealed alterations in 76% of the patients. In three patients, autoimmune psychosis was suspected (4%). Discussion: On the basis of these findings, we conclude that a comprehensive diagnostic procedure according to the FDPP in patients with SSD is worthwhile, considering the detection of secondary, organic forms of SSDs, as well as alterations in "modulating factors" of the disease course, such as vitamin deficiency. Larger studies using comprehensive diagnostic protocols are warranted to further validate this approach.

Keywords: EEG; MRI; antibody; autoimmune psychosis; cerebrospinal fluid; psychosis; schizophrenia; screening.

Grants and funding

n.a./The article processing charge was funded by the Baden-Wuerttemberg Ministry of Science, Research and Art and the University of Freiburg in the funding programme Open Access Publishing.