Diagnosing Late-Onset Psychosis in a Medically Complex Patient: A Diagnostic Challenge.

This case report explores various possible causes of late-onset psychosis and highlights the importance of follow-up care. We report the case of a 65-year-old female with minimal available medical history or contacts, who presented to the hospital after being found unconscious after three weeks of strange behaviors, including partition delusions, multiple phone calls and texts to her friend, and lack of sleep. In the following days, she had various symptoms consistent with delirium, psychosis, and mania. However, she was also found to have a dural calcification and urinary tract infection on imaging and laboratories, respectively. We attempted to distinguish these possible etiologies and understand the best course of action for such a patient with a limited medical history who was subsequently lost to medical follow-up. Utilizing the psychiatric interview, mental status examination, laboratory work, imaging, and available medical and psychiatric history can all help narrow down the most likely etiologies. However, the lack of data given during follow-up visits, regarding patient response to treatment, their full medical and psychiatry history, as well as their understanding of their diagnosis, poses a significant challenge in reaching a definitive diagnosis in such a patient. This underscores the critical need for follow-up care, especially for patients treated for psychosis in acute settings.