Question 1

Can delirium look like schizophrenia?

Accepted Answer

Yes. Delirium can present with paranoia, hallucinations, disorganized speech, and agitation — all features that overlap with schizophrenia. The key differentiating features are the level of consciousness and attention. In delirium, attention is globally impaired, consciousness fluctuates, and onset is acute. In schizophrenia, the sensorium is usually clearer, orientation is generally more preserved, and the onset is typically insidious.

Question 2

Are visual hallucinations always delirium?

Accepted Answer

No. Visual hallucinations should raise suspicion for delirium, substance-related states, or neurologic disease, but they do not rule out primary psychosis. Visual hallucinations can occur in schizophrenia and other psychotic disorders. The modality of hallucination is a probabilistic clue that shifts your differential — it is not a diagnostic rule.

Question 3

Can delirium cause auditory hallucinations?

Accepted Answer

Yes. While visual hallucinations are more characteristic of delirium, auditory hallucinations can occur as well. An acutely confused, disoriented patient with auditory hallucinations should still be evaluated for delirium. Do not assume auditory hallucinations mean psychosis.

Question 4

What is the difference between disorganized thinking and inattention?

Accepted Answer

Disorganized thinking (formal thought disorder) involves abnormalities in the structure and flow of thought — loose associations, tangentiality, derailment, or word salad. The patient may be alert and oriented but their speech does not follow a logical structure. Inattention involves an inability to direct and sustain focus. The patient cannot track a conversation, loses the thread, or cannot complete simple attention tasks. In practice the two can look similar, but inattention with fluctuating awareness points toward delirium, while thought disorder with a clear sensorium points toward psychosis.

Question 5

What is the first step when delirium is suspected?

Accepted Answer

The first step is a medical workup to identify the underlying cause. This commonly includes vital signs, a focused exam, medication reconciliation, and basic laboratory testing guided by the clinical context. Additional testing depends on the presentation. The goal is to find and treat the cause, not just manage the behavioral symptoms.

Question 6

Can a patient with schizophrenia develop delirium?

Accepted Answer

Yes. A preexisting psychotic disorder does not protect against medical illness. Patients with schizophrenia are medically vulnerable populations with elevated rates of metabolic disease, infection, and medication side effects. Any acute change from psychiatric baseline — especially involving new confusion, disorientation, or fluctuating alertness — should prompt delirium screening.

Question 7

Can antipsychotics treat delirium?

Accepted Answer

Antipsychotics may be used in some cases to help manage dangerous agitation in delirium, but they do not treat the underlying syndrome. The essential intervention is identifying and correcting the medical cause. Antipsychotic use in delirium should be judicious, particularly in older adults where risks include QTc prolongation, oversedation, and worsening of hypoactive presentations.

Question 8

Is sundowning specific to delirium?

Accepted Answer

Sundowning — worsening of confusion and behavioral symptoms in the evening and at night — is characteristic of delirium and dementia but is not typical of primary psychotic disorders. Its presence should raise suspicion for a medical or neurocognitive etiology.

Question 9

A 72-year-old man with no psychiatric history is brought to the emergency department by his daughter. Over the past 2 days he has become increasingly confused and agitated. He is pulling at his hospital gown, talking to people who are not in the room, and appears frightened. His daughter says he was completely normal 3 days ago. On examination he is oriented to person only, does not know the date or where he is, and cannot count backward from 20 without losing track. His attention wanders during the interview and he appears more agitated as the evening progresses. Vitals show a low-grade fever of 100.8 F. Which diagnosis is most likely?

Accepted Answer

This presentation has the hallmarks of delirium: acute onset (2 days), fluctuating course with evening worsening, impaired attention (cannot count backward), disorientation (oriented to person only), visual hallucinations (talking to people not in the room), no psychiatric history, and a medical finding (fever) suggesting an underlying cause. Schizophrenia (A) typically presents with insidious onset over weeks to months in younger patients, with relatively preserved orientation. Brief psychotic disorder (B) involves psychotic symptoms lasting 1 day to 1 month, but the disorientation, attentional failure, and acute medical findings point to delirium, not a primary psychotic episode. MDD with psychotic features (D) does not explain the acute confusion, disorientation, or fluctuating consciousness.

Question 10

A 24-year-old man is brought in by his roommate for evaluation. Over the past 3 months he has become increasingly withdrawn, stopped attending classes, and started talking about government surveillance of his apartment. He believes his phone is tapped and that his professors are part of a conspiracy. His roommate reports hearing him talking to himself in his room at night. On examination he is alert and oriented to person, place, and date. He makes eye contact intermittently and his affect is flat. He describes hearing a voice that comments on his actions throughout the day. Vital signs are normal. He denies substance use and his urine drug screen is negative. Which diagnosis is most likely?

Accepted Answer

This patient has a 3-month history of progressive social withdrawal, paranoid delusions (surveillance beliefs), auditory hallucinations (a voice commenting on his actions), and functional decline — all developing insidiously in a young adult with clear sensorium and preserved orientation. This is consistent with a schizophrenia spectrum presentation. Delirium (A) is not supported — there is no attentional impairment, no fluctuating consciousness, no disorientation, and no acute onset. Substance-induced psychotic disorder (C) is less likely given a negative drug screen and denial of use, though longitudinal follow-up would strengthen this determination. Delirium tremens (D) typically presents with acute-onset confusion, autonomic instability, visual hallucinations, and tremor in the context of alcohol withdrawal — none of which are described here.

Question 11

A 68-year-old woman with a 30-year history of schizoaffective disorder is admitted to the psychiatric unit for a psychotic exacerbation. Her baseline includes persistent auditory hallucinations and paranoid ideation managed with clozapine. Three days after admission, nursing reports that she has become newly confused, is not oriented to date or location, is picking at invisible objects on her bedsheets, and alternates between somnolence and agitation over the course of each shift. Her auditory hallucinations are unchanged, but staff note she is now reporting seeing insects on the walls, which is not part of her typical presentation. Which is the most appropriate next step?

Accepted Answer

This patient has a known psychotic disorder but has developed new symptoms that are not part of her baseline: new disorientation, fluctuating consciousness (alternating somnolence and agitation), visual hallucinations (insects on walls, not present at baseline), and psychomotor changes (picking at invisible objects). This pattern is consistent with delirium superimposed on her psychiatric illness. The most appropriate next step is a medical workup — basic labs, urinalysis, medication review (including clozapine levels and metabolic panel), vitals trend, and infectious screening. Increasing clozapine (A) assumes the worsening is psychiatric, which is the dangerous error this question tests. Adding haloperidol (B) may address agitation but does not identify the cause. A neurology consult for seizures (D) is a possible consideration but is not the most appropriate first step when a broader medical workup is indicated.

Question 12

Which of the following clinical features, when present in an acutely psychotic patient, most strongly suggests delirium rather than a primary psychotic disorder?

Accepted Answer

Waxing and waning consciousness with disorientation is the hallmark of delirium and is not characteristic of primary psychotic disorders, in which consciousness and orientation are usually more preserved. Command auditory hallucinations (A) are more commonly associated with schizophrenia spectrum disorders. Paranoid delusions (B) can occur in both conditions and do not reliably distinguish them. Flat affect with social withdrawal (D) is more characteristic of the negative symptom dimension of schizophrenia.

Question 13

A 55-year-old man with alcohol use disorder is admitted to the medical floor 48 hours after his last drink. He is tremulous, diaphoretic, tachycardic, and reports seeing small animals crawling on the bed. He is oriented to person only and cannot sustain attention during the interview. His nurse reports that he was calmer this morning but has become progressively more agitated since mid-afternoon. Which condition best explains this presentation?

Accepted Answer

This is a classic presentation of alcohol withdrawal delirium (delirium tremens). The patient has a known alcohol use history, is 48 hours from last drink (within the typical DT window), and presents with autonomic instability (tremor, diaphoresis, tachycardia), visual hallucinations (animals on the bed), impaired orientation, attentional failure, and a fluctuating course with afternoon worsening. Schizophrenia (A) typically presents with insidious onset, predominantly auditory hallucinations, relatively clearer sensorium, and no autonomic instability. Brief psychotic disorder (C) does not account for the autonomic findings or the temporal relationship to alcohol cessation. Panic disorder (D) does not produce visual hallucinations, disorientation, or this pattern of autonomic instability.

Psychosis vs Delirium

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