Differential Diagnosis

• Single most likely diagnosis
  • A) Bipolar disorder: The patient's symptoms of grandiosity (believing she owns the store), decreased need for sleep, rapid speech, labile affect, and impulsive behavior (shoplifting) are consistent with a manic episode, which is a hallmark of bipolar disorder.
• Other Likely diagnoses
  • C) Brief psychotic disorder: The patient's visions of a "higher being" and delusional thoughts (believing she is the prophet of a new religion) could indicate a brief psychotic disorder, although the presence of manic symptoms makes bipolar disorder more likely.
  • B) Borderline personality disorder: The patient's impulsive behavior and labile affect could be consistent with borderline personality disorder, but the presence of clear manic symptoms and delusions makes this diagnosis less likely.
• Do Not Miss
  • F) Schizophrenia: Although less likely given the patient's age and lack of prior psychiatric history, schizophrenia is a "do not miss" diagnosis due to its potential for severe impairment and treatment resistance. The patient's delusional thoughts and visions could be indicative of schizophrenia, but the presence of manic symptoms and lack of negative symptoms makes this diagnosis less likely.
  • Toxicity or substance-induced psychosis: Although the urine toxicology screening is negative, it is essential to consider the possibility of substance-induced psychosis, especially given the patient's age and behavior.
• Rare diagnoses
  • E) Kleptomania: The patient's shoplifting behavior could be consistent with kleptomania, but this diagnosis is less likely given the presence of other manic and psychotic symptoms.
  • D) Delusional disorder: The patient's delusional thoughts could be indicative of delusional disorder, but the presence of manic symptoms and other psychotic features makes this diagnosis less likely.