Differential Diagnosis

The patient's presentation suggests a complex psychiatric history with multiple symptoms and factors to consider. Here's a differential diagnosis organized into the requested categories:

• Single Most Likely Diagnosis

  • Schizophrenia: This diagnosis is considered the most likely due to the patient's long history of hearing voices since age 7, which is a hallmark symptom of schizophrenia. The patient's history of antipsychotic medication use, periods of hyperarousal and agitation, and reports of seeing things (visual hallucinations) further support this diagnosis. The patient's functioning, although currently part-time, indicates some level of social and occupational functioning, which can be seen in schizophrenia, especially with treatment.

• Other Likely Diagnoses

  • Schizoaffective Disorder: Given the patient's history of mood disorder and the presence of psychotic symptoms (hearing voices, seeing things), schizoaffective disorder is a plausible diagnosis. This condition combines symptoms of schizophrenia with a major mood episode (depressive or manic).
  • Bipolar Disorder with Psychotic Features: The patient's agitation, history of mood disorder, and psychotic symptoms (hallucinations) could also suggest bipolar disorder with psychotic features, especially if the patient's mood symptoms have been prominent and the psychotic symptoms occur primarily during mood episodes.
  • ADHD with Psychotic Symptoms: Although less common, the patient's history of ADHD and the presence of psychotic symptoms could suggest a complex neurodevelopmental disorder. However, ADHD itself does not typically include psychotic symptoms, making this a less likely but still possible diagnosis if considering comorbid conditions.

• Do Not Miss Diagnoses

  • Substance-Induced Psychotic Disorder: Despite the patient's denial of drug use, substance-induced psychosis is a critical diagnosis not to miss, as it can present similarly to primary psychotic disorders. Certain substances can induce psychotic symptoms that are indistinguishable from those of schizophrenia or other psychotic disorders.
  • Neurosyphilis: This is a rare but potentially deadly condition if missed. Neurosyphilis can present with psychiatric symptoms, including psychosis, and is a diagnosis that requires consideration, especially in patients with high-risk behaviors or untreated syphilis.
  • Temporal Lobe Epilepsy: This condition can cause hallucinations, including auditory and visual, and can sometimes be mistaken for a primary psychiatric disorder. It's crucial to consider neurological causes of psychotic symptoms, especially if there are other suggestive signs or symptoms.

• Rare Diagnoses

  • Brief Psychotic Disorder: This is characterized by a sudden onset of psychotic symptoms that last for more than a day but less than a month, followed by a full return to premorbid functioning. Given the patient's long history of symptoms, this diagnosis seems less likely.
  • Psychotic Disorder Due to Another Medical Condition: Various medical conditions can cause psychotic symptoms. While this is a broad category, specific conditions such as thyroid disorders, autoimmune diseases, or certain infections could potentially cause the patient's symptoms, making it a rare but possible diagnosis to consider with appropriate medical evaluation.