CASE: Seeing things
Family members bring Mrs. L, age 82, to the emergency room (ER) because she is agitated, nervous, and carries a knife “for protection.” In the past few months, she has been seeing things her family could not, such as bugs in her food and people trying to break into her house. Mrs. L becomes increasingly frightened and angry because her family denies seeing these things. Her family is concerned she might hurt herself or others.
Despite some hearing loss, Mrs. L had been relatively healthy and independent until a few years ago, when her vision decreased secondary to age-related macular degeneration and diabetic retinopathy. In addition to sensory impairment and diabetes mellitus, her medical history includes mild hypothyroidism and intervertebral disc herniation. She has no history of liver disease or alcohol or substance abuse. A few weeks ago Mrs. L’s primary care physician began treating her with donepezil, 5 mg/d, because he suspected dementia was causing her hallucinations. Otherwise, she has no psychiatric history.
On exam, Mrs. L is easily directable and cooperative. She seems angry because no one believes her; she reports seeing a cat that nobody else could see in the ER immediately before being evaluated. She is frightened because she believes her hallucinations are real, although she is unable to explain them. Mrs. L reports feeling anxious most of the time and having difficulty sleeping because of her fears. She also feels sad and occasionally worthless because she cannot see or hear as well as when she was younger.
A mental status examination shows partial impairment of concentration and short-term memory, but Mrs. L is alert and oriented. No theme of delusions is detected. She has no physical complaints, and physical examination is unremarkable.
The authors’ observations
Mrs. L presented with new-onset agitation, visual hallucinations, and mildly decreased concentration and short-term memory. Our next step after history and examination was to perform laboratory testing to narrow the diagnosis ( Table 1 ).
A basic electrolyte panel including kidney function can point toward electrolyte imbalance or uremia as a cause of delirium. Mrs. L’s basic metabolic panel and liver function were normal. Urinalysis ruled out urinary tract infection.
Mrs. L’s thyroid-stimulating hormone (TSH) level was mildly elevated at 5.6 mU/L (in our laboratory, the upper normal limit is 5.2 mU/L). Hypothyroidism and hyperthyroidism are not associated with hallucinations, but hyperthyroidism is an important medical cause of anxiety and hypothyroidism can cause a dementia-like presentation. CT of the head to rule out a space-occupying lesion or acute process—such as cerebrovascular accident—shows only chronic vascular changes.
Based on Mrs. L’s history, physical examination, and lab results, we provisionally diagnose dementia, Alzheimer’s type with psychotic features, and prescribe quetiapine, 25 mg at bedtime. We offer to admit Mrs. L, but she and her family prefer close outpatient follow-up. After discussing safety concerns and pharmacotherapy with the patient and her family, we discharge Mrs. L home and advise her to follow up with the psychiatric clinic.
Table 1
Suggested workup for elderly patients with hallucinations
| History and physical exam |
| History of dementia, mood disorder, Parkinson’s disease, or drug abuse |
| Presence of delusions or mood/anxiety symptoms |
| Detailed medication history |
| Level of consciousness, alertness, and cognitive function assessment (eg, MMSE) |
| Vital signs (instability may reflect delirium, meningitis/encephalitis, or intoxication) |
| Physical exam (may confirm acute medical illness causing delirium) |
| Neurologic exam (may show focal neurologic signs reflecting space-occupying lesion, signs of Parkinson’s disease, vitamin B12 deficiency) |
| Ophthalmologic history/exam |
| Investigations |
| Electrolyte imbalance, especially calcium |
| Glucose level |
| Uremia, impaired liver function, and increased ammonia |
| CBC |
| Urine drug screen |
| Urinalysis, culture, and sensitivity |
| Additional tests |
| VDRL |
| Arterial blood gas |
| ECG and cardiac enzymes |
| Chest radiography |
| Vitamin B12/folate |
| TSH |
| EEG |
| Serum drug levels |
| CT/MRI of the head |
| Lumbar puncture and cerebrospinal fluid analysis |
| Heavy metal screen |
| HIV screen |
| CBC: complete blood count; CT: computed tomography; ECG: electrocardiography; EEG: electroencephalography; HIV: human immunodeficiency virus; MMSE: Mini-Mental State Exam; MRI: magnetic resonance imaging; TSH: thyroid-stimulating hormone; VDRL: venereal disease research laboratory |
EVALUATION: Lasting hallucinations
Quetiapine improves Mrs. L’s sleep and agitation but does not reduce her hallucinations. She sees a helicopter planting wires on a tree next to her house, a snake in the house, children in her room (some are “beautiful”), fire, and creatures with scary faces. These hallucinations occur mostly when she is alone. She denies hearing or touching the things she sees but continues to feel fear and anxiety when she sees them, although this diminishes with education and reassurance.
The authors’ observations
In Mrs. L’s subsequent psychiatry clinic visits, we gather additional information that helped us rule out several differential diagnoses ( Table 2 ).