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Larry, I hope this helps to explain PD+ syndromes. Deborah aka Tenacity _________________________________________________ Imitators of Parkinson’s Disease A pamphlet prepared by David E. Riley, M.D. Director Movement Disorders Center Mt. Sinai Medical Center Cleveland, Ohio Imitators of Parkinson’s Disease Parkinson’s disease (PD) is a common nervous system disorder which usually affects people around the age of 60. It causes tremor, muscle rigidity, problems with posture and balance, and difficulty with performing voluntary movements. This last feature (akinesia) causes the greatest problems for most people with PD. Voluntary movements are reduced in speed and size. Consequently, patients tend to move slowly, their stride and handwriting get smaller and they don’t blink as often, or swing their arms when walking. Related symptoms include a softer voice, a lack of facial expression (the ‘masked face’), and difficulty turning over in bed, or getting out of chairs or a car. PD typically starts on one side of the body, and remains worse on that side as it gradually progresses. PD involves the loss of a specific group of nerve cells, known as the substantia nigra, which make and release a chemical called dopamine. We usually treat PD by giving people medications that make up for this decrease in dopamine. Neurologist now recognize that a number of other, less common, diseases cause many of the same problems as PD. Usually we distinguish a PD imitator by additional features that are not found in PD (hence the name ‘Parkinson’s plus’ or ‘a-typical parkinsonian’ syndromes. However, these differences are not always obvious, especially at the beginning. As a result, some patients with other diseases look like they have PD at the outset, and may do so for years. The lack of specific laboratory tests compounds the problem, because there is no way to prove whether someone has PD or not. Often, another disease is only suspected when a person does not improve with treatment for PD. Recent autopsy studies show that up to 1 of 4 people thought to have PD during life, actually have a different disease! One of the most important considerations in people with symptoms that suggest PD is that some drugs can produce all the typical characteristics of PD as a side effect. In particular, many drugs used to treat psychiatric problems, and related drugs for stomach problems, including metoclopramide (Reglan), can do this because they block dopamine, mimicking the chemical effect of PD. It is crucial that a doctor be told about all medications that a person is taking, or has used within the last year. Another condition, which is often mistaken for PD is essential tremor. Essential tremor (ET) usually affects both sides from the start and only causes tremor, not the rigidity or akinesia seen in PD. Shaking of the head is a sign of ET, not PD. ET is usually inherited, and many people thought to have hereditary PD actually have ET. Some people with early PD are thought, by family or friends to have had a stroke. In truth, strokes rarely imitate PD, and then, mainly by causing a shuffling gait. Many other conditions may mimic PD in certain respects, but there are three diseases which are most likely to be mistaken for true PD. They differ from one another in important ways, but they also have features in common. For example, they were all first described in the 1960’s, and have names that are barely pronounceable. They are progressive supranuclear palsy, multiple system atrophy and cortical-basal ganglionic degeneration. How do these imitators resemble PD? They copy PD’s tendency to affect people in the second half of their life, and to cause a gradual disappearance (degeneration) of specific groups of nerve cells that are part of the motor system. In fact, all three can involve the substantia nigra, the same part of the motor system damaged in PD, which is why they produce many similar symptoms and findings on the neurologic examination. They also share the tendency to leave the rest of the brain intact, so that non-motor functions of the nervous system, such as language, are usually undisturbed. We do not know what triggers any of these degenerative diseases of the brain, including PD. The specific features that these diseases have in common are the major features of PD: akinesia (difficulty initiating and performing movements, and movements are reduced in speed and size), rigidity (muscle stiffness), tremor (shaking) and disequilibrium (unsteadiness, falling). Together we know them as parkinsonism. PD can be considered but one cause of parkinsonism which is distinguished by special characteristics with respect to the people it affects, the way it evolves, the additional symptoms it causes, it’s response to medication and the damage it does to the central nervous system. How do they differ from PD? Imitators of PD are less likely to cause tremor, especially the rest tremor so common in PD. All three of these diseases lead to a loss of balance and falling early in their course, whereas falls only occur after many years of PD. Perhaps the most significant way in which they differ from PD is that their response to medications which promote dopamine within the brain, especially levodopa, is not nearly as pronounced or sustained as in PD. PD imitators affect parts of the brain’s motor system other than the substantia nigra, and sometimes other systems as well. This is why they cause additional symptoms and signs not found in PD, which is how we usually recognize them. We are still learning how to do this accurately and reliably. Why is it important? It is important for physicians to be able to sort out those people affected by PD imitators from those with true PD. As of the writing, there is no specific treatment for the diseases to be discussed below. However, we are at a relatively early stage of understanding these illnesses, and there is a great deal of research activity in this field. If any useful remedy is going to be developed, it’s effectiveness can be properly determined only when we are reasonably sure the people trying it have the disease in question. As always in medicine, a correct diagnosis allows people to avoid repeated consultations, unnecessary laboratory tests and fruitless treatments. It is equally important that we not enroll patients who have other types of parkinsonism into research studies on PD, because the information learned from them may produce misleading conclusions about PD. For example, one of the first patients who underwent a fetal substantia nigra transplant did not respond, suggesting the operation might have a limited value. When the brain was examined at autopsy, however, what was found was not PD at all, but striatonigral degeneration (see below) PROGRESSIVE SUPRANUCLEAR PALSY This disease is called Steele-Richardson-Olszewski syndrome in Europe, after the 3 Toronto physicians who first recognized and reported it in 1964. The name ‘progressive supranuclear palsy’ (PSP) refers to a characteristic disorder of eye movements which results in difficulty looking downward or upward. This frequently causes problems with reading, walking down stairs, or eating. Trouble with opening or closing the eyes is also common. The eye movement disorder is the most distinctive feature of PSP, but is not always present early on. The most common initial symptom is loss of balance and falling. Other early signs of PSP include a strained or soft (often whispered) voice, slurred speech, impaired swallowing, personality changes and forgetfulness. PSP causes more problems than PD because it damages not only general motor centers but also directly involves areas in the brainstem (the part connecting the brain to the spinal cord) that control eye movement, swallowing, and the other functions that are impaired as noted above. PSP tends to involve both sides of the body equally, unlike PD. PSP tends to affect a slightly older age group than PD and men somewhat more than women. Approximately 5% of people with parkinsonism with no obvious cause will turn out to have PSP. If you would like more information, there is a well-organized national foundation devoted to PSP: The Society for Progressive Supranuclear Palsy, Inc. Johns Hopkins Hospital 5065 Outpatient Center 601 N. Caroline Street Baltimore, Md 21287 MULTIPLE SYSTEM ATROPHY The term multiple system atrophy (MSA) encompasses three variations once thought to be separate diseases: striatonigral degeneration (SND), olivopontocerebellar atrophy (OPCA), and Shy-Drager disease (SDD) or syndrome (SDS). SND produces mainly or only parkinsonism, and principally causes trouble in the form of difficulty starting or slowness in performing voluntary movements. This form of MSA is often only distinguished from PD by the lack of benefit that levodopa brings. The brain areas most affected by SND are the substantia nigra and it’s target center, hence the close resmblance of SND to PD. In SDS, there is parkinsonism like SND along with dysfunction of the autonomic nervous system, which governs the nervous systemís operations not normally under conscious control such as regulation of blood pressure, heart rate, bladder function, intestinal function, sexual function, and sweating. Problems stemming from this aspect of MSA include lightheadedness (due to low blood pressure), urinary retention, incontinence and impotence. Autonomic symptoms often help to distinguish people with MSA from those with PD. Although it is never easy to discuss personal bodily functions, problems of this type are vital clues to a correct diagnosis. Degeneration of the cerebellum and brainstem due to OPCA leads to a form of incoordination known as ataxia, as well as speech and eye movement disturbances. Any form of MSA can also cause spasticity. These three variations of MSA can occur in any combination. MSA tends to start slightly younger than PD. Of the three major imitators, it is usually the most difficult to distinguish from PD because people with MSA mimic PD most closely, and many show at least partial improvement from levodopa. This gives a false sense of security that patients do have PD, since we know that almost nothing else responds consistently to levodopa. Our ability to diagnose MSA may turn out to be the most common of these 3 PD imitators. The first symposium devoted exclusively to MSA took place in London, England, in March 1997. Unfortunately, there is no national association for MSA patients like there is for PSP, however, there is a support group for people with Shy-Drager syndrome, with an emphasis on dealing with the autonomic disturbances caused by MSA. They can be reached at the following address and phone number: Shy-Drager Syndrome Support Group 1607 Silver Ave. S.E. Albuquerque, NM 87106 Tel: 800-SDS-4999 CORTICAL-BASAL GANGLIONIC DEGENERATION This disease, known as corticobasal degeneration in Europe, was first described in Boston in 1968. No further cases were reported until 1985, but since that time cortical-basal ganglionic degeneration (CBGD) has been recognized as another, though less common, imitator of PD. Like PSP, it tends to occur in a slightly older population than PD. The name derives from the fact that both the cerebral cortex (outer gray matter) and the basal ganglia are involved in this disease. The term ‘basal ganglia’ refers to clusters of nerve cells deep in the brain that are components of the motor system. One of the basal ganglia is the substantia nigra, the part of the brain that degenerates in PD. It is also involved in CBGD, so patients have some symptoms and signs similar to those with PD. However, the degeneration of additional parts of the brain causes problems not usually encountered in PD, such as abnormal limb postures (dystonia), loss of sensation of position or movement, arm or leg jerking (myoclonus), and a peculiar disorder of voluntary movement (apraxia) in which people’s ability to transform thoughts into coordinated movements is impaired. Another striking manifestation of CBGD is the alien limb phenomenon, where a person’s limb makes complex movements without their knowledge or despite attempts to refrain from doing so. CBGD shares with PD the tendency to involve just one side of the body at the beginning, and remain worse on that side. Because of a late start, comparatively less is known about CBGD than some other PD imitators. However, we are starting to catch up. A symposium devoted exclusively to CBGD was held in Washington, DC in October 1995. There is no foundation yet established to serve the needs of patients and families with CBGD. CONCLUSION People with a diagnosis of PD often come to see a movement disorders specialist because they are not doing well. One of the most common reasons is that they actually don’t have PD. Medicine is rather late in coming to recognize and distinguish the principal imitators of PD. In part, this is because of the nature of the nervous system. Understanding of neruologic diseases often lags behind developments in other medical fields because the brain is more complex than other organs, and we have less access to it. For example, biopsy of the brain areas involved in these diseases is usually out of the question because it is simply too risky. Since there are no other tests available, we can’t be entirely certain which of these diseases someone had until we examine their brain after they die. Most of the major PD imitators can be identified by proper autopsy studies, but during life, there is no laboratory test that can conclusively distinguish between them. What can you do? Our most pressing need is simply more knowledge. Doctors don’t learn anything new about the symptoms and other effects of a disease unless those who live with it share their experiences with their physicians. If you have any questions or make any new observations about your illness, write them down so you will be sure to mention them at your next visit. Learn as much as you can about your condition and stay informed. What does the future hold? Coping with PD imitators is often difficult. One of the drawbacks to our relatively recent recognition of these diseases is the lack of knowledge about how to treat them effectively. Consequently, PD imitators usually lead to a disabled state more rapidly than PD itself, where treatment can maintain a normal lifestyle for many years. Fatal complications are rare in PD, but more frequent with it’s imitators. However, the outlook is not entirely bleak. Many of the symptoms of PD imitators can be treated individually, and various forms of supportive care often help where medication is lacking. It is important to involve physical therapists, occupational therapists, speech therapists and often dietitians as soon as warranted. There is clearly a great need for more research in this area. The good news is that there is currently a tremendous amount of interest in PD imitators among neurologists. It is hoped that this attention and research activity will lead to meaningful improvements in our ability to more accurately identify and help people with PD imitators in the near future. Acknowledgement: I am indebted to Irene Litvan, M.D., Niall Quinn, M.D. and Steven Reich, M.D. for their helpful comments. _________________________________________________________________ MSN Photos is the easiest way to share and print your photos: http://photos.msn.com/support/worldwide.aspx ---------------------------------------------------------------------- To sign-off Parkinsn send a message to: mailto:[log in to unmask] In the body of the message put: signoff parkinsn