[Autoimmune encephalitis-Diagnostic and therapeutic decision tree from a psychiatric, neurological and ethico-legal point of view : Approach in cases of lack of ability to give consent and permissibility of compulsory treatment].

Patients with severe mental illnesses who are unable to give consent often need a rapid diagnosis and treatment but due to the psychiatric symptoms they often reject such measures. In the routine practice, the question arises to what extent the patient's expressed will should dictate the treatment steps and whether a decision against the patient's will is medically reasonable, ethically justifiable or even demanded and legally permissible. Autoimmune encephalitides, such as N‑methyl-D-aspartate receptor (NMDAR) encephalitis, have recently become important differential diagnoses due to their relative frequency, manifold symptoms and good treatability, as the underlying autoantibodies frequently cause organic psychoses. Using a complex case of a patient with NMDAR encephalitis, which was confirmed in the course of treatment, this article discusses the ethical and legal issues that are relevant in practice, from initial invasive diagnostics to involuntary confinement and compulsory treatment. The article discusses how physicians can respect the autonomy of such patients in the best way and how they can identify and resolve potential contradictions between the free will and the expressed will. Various convictions of physicians about autonomy and coercive treatment are discussed on the basis of the legal situation. Finally, it is discussed how the indications for a short compulsory treatment can be justified before the court of protection on the grounds of an analogy of autoimmune encephalitis to other severe brain diseases.