A 35-year-old woman is brought to the inpatient psychiatric unit by the police after she was found violating the conditions of her restraining order by parking on the side street of her "lover’s" home every night for the past week. Her "lover", a famous hometown celebrity, has adamantly denied any relationship with the patient over the past 6 months. The patient insists that ever since he signed a copy of his album at a local signing, she knew they were in love. Despite him having his own wife and children, the patient insists that he is in love with her and goes to his house to meet in secret. Physical examination of the patient is unremarkable. Urine toxicology is negative. Which of the following statements best describes this patient’s condition?

Symptoms must be present for at least 4 weeks.

The patient will have concurrent psychotic disorders.

The disorder must meet 2 out of the 5 core criteria.

This disorder has a high prevalence rate.

Patients may have a contributing medical condition.

A 26-year-old man is brought to the emergency department by his wife because of bizarre and agitated behavior for the last 6 weeks. He thinks that the NSA is spying on him and controlling his mind. His wife reports that the patient has become withdrawn and at times depressed for the past 3 months. He lost his job because he stopped going to work 4 weeks ago. Since then, he has been working on an invention that will block people from being able to control his mind. Physical and neurologic examinations show no abnormalities. On mental status examination, he is confused and suspicious with marked psychomotor agitation. His speech is disorganized and his affect is labile. Which of the following is the most likely diagnosis?

Schizotypal personality disorder

Two dizygotic twins present to the university clinic because they believe they are being poisoned through the school's cafeteria food. They have brought these concerns up in the past, but no other students or cafeteria staff support this belief. Both of them are average students with strong and weak subject areas as demonstrated by their course grade-books. They have no known medical conditions and are not known to abuse illicit substances. Which statement best describes the condition these patients have?

Can affect two or more closely related individuals.

A trial separation is likely to worsen symptoms.

The disorder is its own disease entity in DSM-5.

Antipsychotic medications are rarely beneficial.

Cognitive behavioral therapy is a good first-line.

A 22-year-old man is brought to the emergency department by his father because he is having bizarre thoughts. The patient says that he is being haunted by aliens from outer space. The father is worried as his son has had these symptoms for the past 7 months and lately, it seems to be getting worse. He has become more self-obsessed and does not seem to have any interest in his favorite activities. He has no plans to harm himself or others but spends a lot of time and energy building ‘defenses’ in and around his room as he is absolutely sure that aliens will come to get him soon. His blood pressure is 121/79 mm Hg, pulse 86/min, respiratory rate 15/min, temperature 36.8°C (98.2°F). Which of the following is correct regarding the patient’s symptoms?

It would benefit from psychosurgery.

It is best treated with cognitive behavioral therapy alone.

It falls under the disorganized thinking domain.

A 21-year-old man presents to the emergency room requesting surgery to remove "microchips," which he believes were implanted in his brain by "Russian spies" 6 months ago to control his thoughts. He also reports hearing the "spies" talk to each other through embedded "microspeakers." You notice that his hair appears unwashed and some of his clothes are on backward. Urine toxicology is negative for illicit drugs. Which of the following additional findings are you most likely to see in this patient during the course of his illness?

Asociality, flat affect, and alogia

Anhedonia, guilty rumination, and insomnia

Grandiose delusions, racing thoughts, and pressured speech

Amnesia, multiple personality states, and de-realization

Intrusive thoughts, ritualized behaviors, and anxious mood

A 23-year-old woman is brought to the physician by her father because of irritability, mood swings, and difficulty sleeping over the past 10 days. A few days ago, she quit her job and spent all of her savings on supplies for a “genius business plan.” She has been energetic despite sleeping only 1–2 hours each night. She was diagnosed with major depressive disorder 2 years ago. Mental status examination shows pressured speech, a labile affect, and flight of ideas. Throughout the examination, she repeatedly states “I feel great, I don't need to be here.” Urine toxicology screening is negative. Which of the following is the most likely diagnosis?

Attention-deficit hyperactivity disorder

A 31-year-old woman comes to the physician because she thinks that her “right wrist is broken.” She says that she has severe pain and that “the bone is sticking out.” She has not had any trauma to the wrist. Her medical records indicate that she was diagnosed with schizophrenia 2 years ago and treated with olanzapine; she has not filled any prescriptions over the past 4 months. Three weeks ago, she stopped going to work because she “did not feel like getting up” in the morning. Vital signs are within normal limits. Physical examination of the right wrist shows no visible injury; there is no warmth, swelling, or erythema. Range of motion is limited by pain. On mental status examination, she has a flat affect. Her speech is pressured and she frequently changes the topic. She has short- and long-term memory deficits. Attention and concentration are poor. There is no evidence of suicidal ideation. Urine toxicology screening is negative. An x-ray of the wrist shows no abnormalities. Which of the following is the most appropriate response to this patient's concerns?

“I cannot see any injury of your wrist and the physical exam as well as the x-ray don't show any injury. I imagine that feeling as if your wrist was broken may be very uncomfortable. Can you tell me more about what it feels like?”

“It seems as though you are having a schizophrenia relapse. If you don't follow my recommendations and take your medications, you will most likely have further and possibly more severe episodes.”

I understand your concerns; however, your symptoms seem to be psychological in nature. I would be happy to refer you to a mental health professional.

You are clearly distressed. However, your tests do not suggest a physical problem that can be addressed with medications or surgery. I suggest that we meet and evaluate your symptoms on a regular basis.

I can imagine that you are uncomfortable. That certainly looks painful. Let's take care of this injury first and then we should talk about your problems getting up in the morning.

A 27-year-old woman is brought to the office at the insistence of her fiancé to be evaluated for auditory hallucinations for the past 8 months. The patient’s fiancé tells the physician that the patient often mentions that she can hear her own thoughts speaking aloud to her. The hallucinations have occurred intermittently for at least 1-month periods. Past medical history is significant for hypertension. Her medications include lisinopril and a daily multivitamin both of which she frequently neglects. She lost her security job 7 months ago after failing to report to work on time. The patient’s vital signs include: blood pressure 132/82 mm Hg; pulse 72/min; respiratory rate 18/min, and temperature 36.7°C (98.1°F). On physical examination, the patient has a flat affect and her focus fluctuates from the window to the door. She is disheveled with a foul smell. She has difficulty focusing on the discussion and does not quite understand what is happening around her. A urine toxicology screen is negative. Which of the following is the correct diagnosis for this patient?

Schizotypal personality disorder

Types of delusional disorder (persecutory, jealous, etc.) — USMLE Lesson

Delusional Disorder - Reality's Remix

Core Feature: A fixed, false belief lasting ≥1 month. Crucially, functioning outside the delusion is not markedly impaired, and behavior is not obviously bizarre.
Subtypes:
- Persecutory: Belief of being conspired against, spied on, or harassed. Most common type.
- Jealous: Convinced a partner is unfaithful.
- Erotomanic: Believes another person (often of higher status) is in love with them.
- Grandiose: Inflated sense of worth, power, or identity.
- Somatic: Delusions involving bodily functions or sensations.

⭐ Unlike schizophrenia, hallucinations in delusional disorder are absent or not prominent.

Delusion Flavors - The Who's Who

📌 Mnemonic: "JPEGS"

Jealous: Convinced a partner is unfaithful, despite lack of evidence.
Persecutory: Belief of being plotted against, spied on, or harmed. The most common type.
Erotomanic: Belief that another person (often of higher status) is in love with them.
Grandiose: Inflated sense of worth, power, knowledge, or identity.
Somatic: Preoccupation with having a physical illness or defect.

Mixed Type: Features of more than one type are present, but no single theme dominates.
Unspecified Type: The dominant delusional belief cannot be clearly determined.

⭐ The persecutory type is the most common and may be associated with a higher risk of aggression or violence as the individual attempts to "defend" themselves from perceived threats.

Diagnosis - Spot the Difference

Types of Delusional Disorder and Descriptions

Core Feature: Fixed, false belief lasting ≥1 month without other psychotic symptoms. Functioning is not markedly impaired apart from the delusion's impact.

Type	Core Belief / Delusion
Persecutory	Belief of being conspired against, cheated, spied on, followed, poisoned, or harassed.
Jealous	Conviction that a spouse or lover is unfaithful (without due cause).
Erotomanic	Belief that another person, often of higher status, is in love with them.
Grandiose	Inflated self-worth, power, knowledge, identity, or a special relationship to a deity/famous person.
Somatic	Belief of having a physical defect or medical problem (e.g., infestation, foul odor).

High‑Yield Points - ⚡ Biggest Takeaways

Core feature: ≥1 month of non-bizarre delusions with unimpaired functioning.

Persecutory is the most common type; others include jealous, erotomanic, grandiose, and somatic.

Erotomanic delusion involves a belief that a person, typically of higher status, is in love with them.

Jealous type is a fixed belief in a partner's infidelity.

Somatic type involves delusions about bodily functions or sensations.

Unlike schizophrenia, hallucinations are absent or not prominent, and there are no negative symptoms.

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