symptoms of parkinsons disease : Other Parkinsonism Syndromes

The characteristic symptom-complex of Parkinson disease (tremor, rigidity, bradykinesia, postural instability) is termed parkinsonism. This is a general term and not all patients with parkinsonism have typical Parkinson disease. Early in the disease process it may be difficult to know whether a patient has typical Parkinson disease or a syndrome that mimics it. The development of additional symptoms and the subsequent course of the disease generally points to the correct diagnosis.

Recognizing other causes of Parkinsonism

A number of patients with parkinsonism do not have PD. One study of patients with parkinsonism found that 65% had PD, 18% had drug-induced parkinsonism, 7% had vascular parkinsonism (i.e. from blocking-up of the small blood vessels feeding the brain) and 10% had atypical parkinsonism. Atypical parkinsonism should be considered particularly in patients with poor dopaminergic responsiveness, early loss of balance, prominent intellectual changes (dementia), rapid onset or progression, conspicuous postural hypotension, and little or no tremor. The present of neurological findings not associated with classic Parkinson disease, such as myoclonic jerking (shock-like sudden muscle contractions), should also suggest other diagnostic possibilities. The autonomic nervous system regulates the “involuntary” internal functions of the body, such as blood pressure, heart rate, and bladder, rectum, and sexual function. It may be affected in certain atypical parkinsonian syndromes.

Medication-induced Parkinsonism

Although tremor and postural instability may be less prominent, this condition may be indistinguishable from Parkinson disease. Medications frequently associated with the development of parkinsonism include antipsychotics, metaclopramide, reserpine, tetrabenazine and some calcium-channel blockers (especially cinnarizine and flunarizine). The parkinsonism usually resolves within weeks to months after discontinuing the offending medication.

Progressive Supranuclear Palsy (PSP)

Early onset of imbalance, frequent falls, rigidity of the trunk, and (eventually) eye-movement problems characterize PSP. Symptoms usually begin after age 50 and progress more rapidly than with Parkinson disease. The most characteristic eye movement abnormality is a vertical gaze paralysis. Upgaze and downgaze are therefore limited. Patients may present with frequent falls while walking downstairs, because they cannot look down. Dementia develops later in the disease. There is no specific treatment for PSP. Dopaminergic treatment should be tried but often provides little benefit. Supportive measures such as speech therapy, physical therapy, and antidepressants may help.

Corticobasal Degeneration (CBD)

CBD is the least common of the atypical causes of parkinsonism. It often affects patients quite asymmetrically and progresses more rapidly than Parkinson disease. The initial symptoms of CBD usually develop after age 60 and include asymmetric bradykinesia, rigidity, limb dystonia (abnormal postures), postural instability, and disturbances of language (speech expression or comprehension). There is often marked and disabling apraxia, i.e., it becomes difficult or impossible to use the affected limb even though there is no weakness or sensory loss.

There is no specific treatment for CBD. Supportive treatment such as botulinum toxin for dystonia, antidepressant medications and speech and physical therapy may help. Levodopa and dopamine agonists seldom offer benefit.

Multiple System Atrophy (MSA)

MSA is a neurodegenerative disease of unknown cause. Initially it may be difficult to distinguish from Parkinson disease, but it is far less common and progresses more rapidly. The mean age of onset is in the mid-50s. Clinically, it presents with bradykinesia, poor balance, abnormal autonomic function, rigidity, difficulty with coordination, or a combination of these features. Abnormalities of autonomic function include impotence, low blood pressure upon standing, excessive or reduced sweating, and constipation. There are three subtypes of the illness, each affecting different systems.

Striatonigral degeneration (SND) is characterized by parkinsonism, but without much tremor and with poor response to Sinemet. In the Shy-Drager syndrome, parkinsonism and autonomic abnormalities are conspicuous. In olivopontocerebellar atrophy (OPCA), patients have lack of coordination and clumsiness which affect balance and gait.

As MSA progresses, other symptoms and signs develop that reflect involvement of a different system. Patients with the parkinsonian presentation typically have an asymmetrical tremor, bradykinesa, rigidity and postural instability. Men often develop impotence; both men and women often experience urinary urgency and incontinence. Patients with Shy-Drager syndrome present with more prominent symptoms of autonomic dysfunction.

Although 30% of patients with MSA obtain a definite but short-lived benefit from levodopa and dopamine agonists, the parkinsonism is typically poorly responsive to medications. Dyskinesias and dystonia emerge in half of treated patients. There is not much experience of using deep brain stimulators (DBS) for MSA, but some researchers have found a modest benefit of DBS that persisted for over two years in a few patients.

Vascular Parkinsonism

Multiple small strokes can cause parkinsonism. Patients with this disorder are more likely to present with gait difficulty than tremor and are more likely to have symptoms that are worse in the lower than upper limbs. Some will also report the abrupt onset of symptoms or give a history of step-wise deterioration (symptoms get worse, then plateau for a period). Treatment is the same as for Parkinson disease, but the results are often disappointing.

Dementia with Lewy bodies (DLB)

This disorder is characterized by early dementia, prominent hallucinations, fluctuations over the day in cognitive status, and parkinsonism. The neuropsychological profile is characterized by deficits in attention, executive function (problem solving, planning) and visuospacial function (the ability to produce and recognize figures, drawing or matching figures).

Treatment with cholinesterase inhibitors may reduce delusions, apathy, agitation and hallucinations. A severe reaction to antipsychotic medication is another feature of this disease. If behavioral problems do not respond to cholinesterase inhibitors, low-dose treatment with atypical antipsychotic medications (quetiapine, resperidone, or clozapine) may be considered. Although motor symptoms may respond to levodopa, hallucinations may become worse with its use.

The above information was contributed by Mariann Di Minno, RN, MA, and Michael J. Aminoff, MD, DSc, of the Parkinson’s Disease Clinic and Research Center at the University of California, San Francisco.