Parkinson’s disease: a quick one on one

Parkinson’s disease (PD) is a common neurological disease. This disorder of the brain is seen in people of all races and both sexes. PD is caused by the deficiency of a neurochemical called DOPAMINE in the brain. In this blog post I shall discuss the clinical presentation and diagnosis of PD.

Parkinson’s disease is included under the category of neurodegenerative brain disorders. What that means is that the disease is progressive. Once the disease starts, it slowly progresses. The rate of progression though varies from patient to patient. The disease onset is usually insidious. Most people first exhibit signs of the disease after age 60 (in some people the disease may start in the late 40’s or in their 50’s-this is then referred to as Early Onset Parkinson’s).

Disease onset-onset of PD is usually insidious and at times may not be noticed by the patient or the family. Typical first symptom may be a slight tremor (shaking) in the thumb of one hand/finger of one hand, the hand itself or the chin. The tremor is not disabling at onset and hence ignored by the patient/family. It is important to emphasize here that NOT ALL TREMORS ARE PD. There are numerous causes of tremor, many which are benign (do not signify any serious disease). PD tremor has some special characteristics (features) which helps to distinguish it from other types of tremors.

CHARACTERISTICS (FEATURES) OF PD TREMOR

  1. The tremor is usually insidious in onset and of low amplitude.
  2. The tremor is usually asymmetrical at onset (one thumb/one hand). As the disease progresses the tremor becomes more prominent and may involve both the sides of the body.
  3. PD tremor is typically what is referred to as a RESTING TREMOR. What this means is that the tremor is most prominent when the hands are completely at rest (example-the tremor is noted when the patient’s hands are resting on his/her lap, resting on the driving wheel). This is an IMPORTANT distinguishing feature of PD tremor. Tremors which are more prominent when the hands are extended in front (POSTURAL TREMOR) or while in motion are usually not due to PD.

CLINICAL PRESENTATION OF PD (SIGNS AND SYMPTOMS)

PD initially presents with motor symptoms. Patients do not have sensory symptoms such as pain, numbness, tingling. The common motor symptoms of PD are the following:

  1. Tremor: tremor of PD is a resting tremor (see above).
  2. Bradykinesia: the word bradykinesia means “slowness of movement” and is one of the main symptoms of PD. The patient is slow to walk, slow to initiate movement. As PD progresses, the patient becomes more and more bradykinetic (slow). There is loss of spontaneous movements such as facial expressions, gesturing, eye blinks.
  3. Rigidity: rigidity is another cardinal symptom of PD and refers to the stiffness which PD patients feel in their muscles. Rigidity can be detected by the neurologist on clinical examination.
  4. Disturbance of gait and posture: patients with PD experience a disturbance in their gait (how a person walks) and posture. A patient with PD is usually stooped (bent) forwards and walks with short quick steps. This is referred to as the SHUFFLING GAIT OF PD. This disturbance of gait and posture makes PD patients more prone to falls. It is important to emphasize here that FALLS ARE AN INPORTANT CAUSE OF MORBIDITY IN PD PATIENTS.

Photo source: *photo: https://www.labiotech.eu/medical/axovant-parkinsons-disease-gene/ (the above image has been edited)

DIAGNOSIS OF PD

The diagnosis of PD is predominantly clinical and has not changed much since the disease was first described by James Parkinson, an English surgeon in his now famous 1817 work AN ESSAY ON THE SHAKING PALSY.

PD is diagnosed in the following way:

  1. Clinical examination by a neurologist: neurologists are able to diagnose PD after taking a history and doing a neurological examination in which they assess for tremor, bradykinesia, rigidity and gait/posture.
  2. Neuroimaging: it is important to emphasize that neuroimaging studies such as CT scan head and MRI brain are usually reported normal in patients with PD.
  3. New imaging modalities: DaT scan is a new imaging test which uses a small amount of a radioactive tracer drug to determine how much dopamine is available in a patient’s brain. It is important to emphasize that DaT scan is neither needed nor a definitive test for PD diagnosis. It is primarily helpful in differentiating Parkinson like diseases (Parkinsonian syndromes) from a more benign condition called essential tremor (ET).

DISCLAIMER: The information in this blog is for educational and informational purposes only. It does not constitute medical advice. Use of the site content does not establish any patient-doctor relationship. If you choose to write to me or post a comment on this blog, please do not divulge any personal medical information.

Nitin K Sethi, MD, MBBS, FAAN

Early signs of Parkinson’s disease: making the diagnosis

Early signs of  Parkinson’s  disease: making the diagnosis

Nitin K Sethi, MD

Assistant Professor of Neurology

New York-Presbyterian Hospital

Weill Cornell Medical Center

New York, NY 10065

 

Well it is the start of a new year and a new decade. Welcome twenty ten. I wish all the readers of my blog a very happy new year. Recently I saw a patient in my office and he shall be the subject of my post. He came to see because of his tremor. Actually I should not say he came to see me, the patient infact felt there was nothing wrong with him.

Dr. Sethi, I have noticed a tremor in my right hand for the past 3 months. It does not bother me. I feel fine. It is my wife who wants me to come and get this checked out” he said.

As I examined him I realised his ” hand shakes” problem was something more sinister as I found tell tale signs suggestive of Parkinson’s disease. That is what I shall discuss here, how does one go about making the diagnosis of Parkinson’s disease ? What are the points in the history and examination that make me as a doctor consider this diagnosis?

Parkinson’s disease may start off very innocuously. All my patient had noticed was that for the past3 months he had a tremor in his right hand. The tremor did not bother him and did not interfere with any activity of daily living such as writing, getting dressed, eating and so forth.  He in fact would not have sought a neurological consultation if his wife had not insisted.  That said and done, there are certain characteristics of the tremor which can aid in the diagnosis. The classical tremor described with Parkinson’s disease is what is called a resting tremor. Now pray what does that mean? Simple the tremor is most prominent when the hands are rest. Let me explain with the aid of an example. While I was talking to my patient and eliciting his medical history, my visual attention was focussed at his hands which were at rest on his lap. I noticed his right hand to have a tremor, the tremor became more prominent when he was distracted. If I asked him to look at his right hand, he could stop the tremor for a few seconds but then the tremor came back. He did not have  a tremor in his left hand or in his legs. When the arms were extended (held up in front of him), the tremor  abated.

So point number 1:  Sporadic Parkinson’s disease usually starts of in the sixth to seventh decade of life. The initial presentation may be quite subtle with only a mild tremor. The tremor initially is asymmetrical (that is it may only be in one hand) and classically it is a resting tremor (most prominent when the hands are completely at rest). The tremor becomes less prominent when the hands are doing something (in motion) and completely abates when the patient falls asleep. Remember the tremor at least initially during the disease course may not be bothersome for the patient and may not impair his quality of life. Hence the patient may not seek attention and the diagnosis may be delayed.

There are some other early signs of Parkinson’s disease. On close inspection I was able to document them in my patient too. When he spoke to me, his face lacked the usual emotions. What do I mean by that. Well when we speak our face show a variety of emotions, we frown, we roll our eyes, sometimes our eyes smile and so forth. A Parkinson’s disease patient has what is called a “mask-like” face-there is a paucity of normal facial expressions.

So point number 2.  Mask like face

Parkinson’s disease patients have a characteristic gait. For want of better words, they walk stiffly. The classical gait is described as bent forward, walking with short quick steps (as if they are going to topple over) and the arms are held by the side (they do not have the usual arm swing).

So point number 3. Gait (They walk funny!!!)

So if you or any of your loved ones show these signs, make sure you get a neurological opinion. Your doctor shall be able to elicit further points in the history and examination which shall help secure the diagnosis of sporadic Parkinson’s disease. Remember the diagnosis of Parkinson’s disease remains a clinical diagnosis (one made by a doctor after history and examination). There are no confirmatory tests (at least none that are used in the office setting).