Learning Objectives
- Lewy body dementia is a condition of dementia with Parkinsonian features, often with hallucinations and REM sleep behavior disorder
- Patients with this disorder may be sensitive to neuroleptic medications
- If behavior is unsafe or aggressive, treatment with quetiapine or risperidone may be helpful
History
CW, a 68 year old retired factory worker, is brought to the emergency room for behavioral concerns. His son and his wife accompany him. They say he was outside the house with a baseball bat, trying to chase away some intruders he saw. A few days earlier, he lit a pile of garbage on fire in the middle of the street in front of his home. There was no damage in either episode. They say he has been acting erratically, and they fear for his safety. They say he fell a couple of times for no apparent reason. It takes him a long time to get dressed in the morning. When he is asked about these events, he says he is old, and tired, and that he likes to take his time. About the falling, he says, “everyone has accidents” and that he thought there was something toxic in the garbage, which needed to be burned. About the incident with the bat outside the house, he said he saw some grey people looking at him through the bushes, he thought they were juveniles in his neighborhood, and he felt they needed to be chased away.
CW has a history of allergies to penicillin. His medications are aspirin ad lisinopril. He has a past medical history of hypertension.
He has been married for 47 years. He has smoked cigarettes since the age of 16. He has 1-2 beers each day. He has not worked since the age of 62.
His mother died of pneumonia at age 81 and suffered from Alzheimers disease. He did not know his father. He has no brothers or sisters.
Review of systems indicates he has not had chest pain or palpitations. He has not had a fever, coughing or trouble breathing. He has had a good appetite and no changes in his weight. He has not had joint pains. He has not had bleeding or bruising. He has had trouble sleeping, sometimes having violent reenactments of his dreams, causing his wife to move into the living room to sleep. He has not had headaches, trouble with swallowing, or alteration of his vision. His urinary and bowel habits are not changed.
Examination
His temperature is 98.4 F. His blood pressure is 158/92 and his pulse is 82. He is alert, sitting upright on a gurney, and he appears attentive. He is a muscular, thin man appropriate for his age. His heart sounds are present without murmurs. His carotid sounds are normal. His pupils are 3 mm and reactive, and his funduscopic exam is normal. He is alert and he answers questions. He does not appear irritable. He is oriented to person and place, but not to the date. His naming function is normal, but recall is impaired, and awareness of current events is limited. His attention is moderately limited. He follows commands, sometimes with prompting. He is able to write but his drawing is poor. He is unable to draw a clock face. He does not appear to have nystagmus, and eye movements are normal. Facial expression is normal and hearing is normal. Facial sensation is normal. Shoulder shrug and tongue movement are normal. Passive muscle tone is increased in the right arm, but not the left, and there is no tremor. Muscle strength is normal. There is bradykinesia of fine finger movements in the right hand. Reflexes are normal in the biceps, quadriceps and gastrocnemius. Toes are downgoing. Sensation to pinprick is normal. Finger nose finger movements are normal. He has a slow walk, with small steps, and reduced right arm swing. He cannot tandem walk. He falls easily when pulled backwards, but the Romberg exam is not remarkable.
A man with symptoms of Parkinsons disease and dementia may be suspected of having Lewy Body dementia. Other helpful characteristics are the visual hallucination symptoms, especially of white, brown or grey people or animals, in the absence of a dopamine agonist. Dopamine agonists can cause a visual hallucination like these. Another associated symptom is the sleep-related behavior, which is typical of REM sleep behavior disorder, and is often present in this condition. A differential diagnosis includes delirium (which has many causes), Alzheimers disease with Parkinsonism, and cerebrovascular or neoplastic disease.
The first important step in evaluating a person in this condition is to promote personal and family safety and to determine if a medical illness of adverse reaction to medication is present. Keeping the patient under observation with minimal stimulation may help to keep them calm, although this is not always easy to accomplish. In this case, medications do not garner suspicion, because he does not use any. At other times, medicines that affect the CNS, such as pain medicines, mood medicines, and Parkinsons treatments could be potential causes. Testing for medical disorders, such as urinary tract infection, uremia, hyponatremia, and pneumonia is important. It can be surprising how a simple medical illness will masquerade as a cognitive disorder. In this case, it may be expected these tests would be normal, but they should be done as a matter of diligent attention to alternative causes.
A secondary evaluation may include a CT scan or MRI study of the head. The latter is preferred, but it may be limited by movement artifact, depending on the patient’s cooperation with the study. Both tests are helpful for evaluating some of the causes, but the MRI would be preferred, since a small lesion of the midbrain could be found, if any is found at all.
An occult malignancy, such as metastatic lung cancer, may also be a factor in a case like this. A plain chest film with a CT scan or MRI scan result of the brain would be helpful.
If alternative causes of symptoms are not found by a thorough medical exam, and there are sufficient clinical features of Lewy body dementia, this may be the appropriate diagnosis. The key clinical features of Lewy body dementia are variable cognitive difficulty especially with respect to executive function, motor features suggestive of Parkinsons disease, and complex hallucinations, often of a visual origin. Patients with Lewy body dementia also show Lewy body formations within the brain on autopsy. REM sleep behavior disorder is common in this disorder. Patients with LBD tend to be remarkably fragile to neuroleptic medications such as haloperidol, and these should not be used with these patients.
Treatment
When behavioral concerns are present, and safety is an issue, medication other than dopamine antagonists may be helpful. These include quetiapine and risperidone. These may have a side effect of sedation, and this effect may be desirable at certain times of the night, depending on the circumstances.
Medications useful to treat Alzheimer disease may not be effective in LBD. They are often prescribed, with the expectation that there is some overlap in the pathology of the two illnesses. This is controversial and has not been formally established as a standard of care.
There is no cure for Lewy body dementia. Supportive care, safety and quality of life are important issues in handling such a case. Establishing durable power of attorney and living will are important in this type of case as they are in the case of Alzheimer disease.
Review Questions
- Patients with Lewy Body dementia often have dementia and:
a. hallucinations
b. Parkinsonian symptoms
c. REM sleep behavior disorder
d. incontinence
e. A, B, and C - Patients with Lewy Body Dementia should avoid these medications:
a. ciprofloxacin
b. haloperidol
c. chlorpromazine
d. quetiapine
e. All of the above
3. Medical treatment of agitation in a person with Lewy Body dementia could be
a. lorazepam
b. haloperidol
c. chlorperazine
d. quetiapine
e. chlorpromazine
f. All of the above