What is the most likely diagnosis for a 48‑year‑old male senior executive who for the past two weeks has developed paranoid delusions that he is being undermined at work, monitored via cameras and microphones, and that his thoughts are being read?

Acute Psychotic Episode

The most likely diagnosis is D) Acute psychotic episode, as this 48-year-old man presents with the cardinal features of new-onset psychosis: paranoid delusions (being undermined at work, monitored via cameras/microphones) and thought broadcasting (thoughts being read) over a two-week timeframe, with apparently preserved consciousness and awareness. 1

Diagnostic Reasoning

Why This is Psychosis

The clinical presentation demonstrates two cardinal features of psychotic symptomatology: delusions (fixed false beliefs about persecution and surveillance) and what appears to be a first-rank symptom (thought broadcasting). 1 Critically, the guidelines emphasize that in contrast to delirium or other forms of altered mental status, awareness and level of consciousness in patients with psychosis are frequently intact 2. This patient's ability to articulate coherent (albeit delusional) concerns about workplace persecution suggests preserved consciousness.

The two-week duration is consistent with acute psychosis rather than chronic psychiatric illness, and the age of onset (48 years) falls within the range where both primary and secondary causes must be considered. 2

Ruling Out Other Options

Substance-induced psychosis (cocaine or heroin) must be considered as secondary causes, since psychosis can be "directly related to drug/alcohol use, withdrawal, or an underlying medical cause." 1 However, the question stem provides insufficient evidence of substance use. Cocaine can cause paranoid psychosis, but typically presents with additional features like agitation, tachycardia, or recent use history. Heroin withdrawal causes dysphoria and physical symptoms but rarely causes organized paranoid delusions.

Hyperthyroidism can present with psychiatric symptoms including anxiety, agitation, and rarely psychosis, but would typically include physical signs (tremor, tachycardia, weight loss, heat intolerance). 2 The guidelines note that "endocrine disorders" are among medical conditions that may present with psychotic symptoms, but this is uncommon. 1

"All of the above" (Option E) is incorrect because the clinical presentation most parsimoniously fits acute psychosis as the primary diagnosis, though secondary causes must be investigated.

Critical Next Steps: Primary vs. Secondary Psychosis

The immediate diagnostic priority is distinguishing primary from secondary psychosis, as this fundamentally changes management and prognosis. 1, 2, 1, 2, 1

Mandatory Workup

For secondary causes of psychosis, treatment is aimed at the underlying medical cause and control of the psychotic symptoms. 1 The guidelines specify that medical conditions presenting with psychotic symptoms include:

• Substance intoxication/withdrawal: Urine drug screen, alcohol level, detailed substance use history
• Endocrine disorders: TSH, comprehensive metabolic panel (hyperthyroidism, Cushing's, etc.)
• Metabolic derangements: Electrolytes, glucose, renal/hepatic function
• Infections: Consider CNS infections if fever or altered consciousness develops
• Neurologic disorders: Neuroimaging if focal signs, new-onset seizures, or atypical features 1

Common Pitfall

Do not assume this is primary psychiatric illness (schizophrenia, bipolar disorder) without excluding organic causes. 2 Research shows that "paranoid symptoms were found in 40% of patients admitted to a university general hospital psychiatric unit," and "only one half of those who had paranoid delusions had paranoid schizophrenia. A significant number had affective disorders or organic brain disorder." 3 Misdiagnosis leads to inappropriate treatment and missed reversible causes.

Management Algorithm

1. Ensure safety: Assess for danger to self/others given paranoid content
2. Rule out delirium: Verify intact attention, no fluctuating consciousness, no acute medical illness 1
3. Obtain collateral history: Timeline, substance use, medical history, medication changes, stressors
4. Laboratory evaluation: CBC, CMP, TSH, B12, RPR, HIV, urine drug screen
5. Neuroimaging: Consider if age >50, focal neurologic signs, cognitive deficits, or atypical presentation 1
6. Symptom control: Low-dose atypical antipsychotic for acute management while workup proceeds 4
7. Psychiatric consultation: For definitive diagnosis and ongoing management

Treatment Considerations

If no secondary cause is identified, treatment of primary psychosis involves pharmacologic management with antipsychotic medications, psychological therapy, and psychosocial interventions. 1 However, given the acute onset at age 48 in a previously high-functioning executive, maintain high suspicion for an underlying organic etiology throughout the evaluation.

The two-week timeframe is critical: this represents either a first psychotic break (requiring urgent intervention to prevent deterioration) or an undiagnosed medical condition manifesting as psychosis (requiring identification and treatment of the underlying cause). Both scenarios demand immediate comprehensive evaluation rather than premature diagnostic closure.