An elderly man who presented with falls
In this week’s episode of the Teaching through Clinical Cases series, Dr. Sneha Mantri returns to comment more about unusual causes of Parkinsonism. She was just on the show two weeks ago discussing the way medications can cause Parkinsonian features. That’s a good one to review if you haven’t already. But today, we’re reviewing the case of a patient who had an interesting constellation of axial rigidity, autonomic disturbances, and ocular dysmotility. Sounds a little Parkinsonian to me, but you’ll have to hear the whole story.
The patient was a 68 year old gentleman. He started to fall about 8 months ago, initially thought he was tripping over things. This started just with going down the stairs, but now is happening even on level ground. In the last six months, he has had trouble reading the newspaper, but no trouble reading on the computer. This is a red flag in the movement disorders world. He denied frank double vision. No tremor. No trouble swallowing. He denied changes in his voice, but his wife thought his voice was a little softer than it had used to be. He was seen by a general neurologist 6 months ago, was worked up for neuropathy (B12 slightly low, other labs normal), and told he had Parkinson Disease (PD). He was started on carbidopa/levodopa which was uptitrated with limited effect.
Sure, this could be on the spectrum of PD. It would be hard to know if trouble descending stairs means this was the story of a patient with progressive proximal weakness involving the hip girdle, as in dermatomyositis or a limb girdle muscular dystrophy—a story of impaired sensation or proprioception of where the feet are in space, so maybe a lower extremity polyneuropathy, radiculopathy, or posterior column process, or if it was a story that maybe has something to do with more than just motor skills and coordination. Maybe the patient had trouble with downgaze, which is slow and progressive in cases of early PSP and rarer conditions like adult-onset Tay Sachs and Wilson’s disease, among others. The patient did have trouble reading the paper, after all–and not reading a computer. But maybe that just meant his visual acuity was poor? To help localize the lesion for this type of complaint, I’d recommend using a book like Localization in Clinical Neurology.
In terms of non motor symptoms, no lightheadedness on standing, no constipation, no hyposmia–some of the autonomic symptoms we look for in synucleinopathies like idiopathic PD. But he did endorse significant dry eyes and occasional dry mouth. He has had dream enactment behavior for the last 6 weeks or so, after reaching a target dose of CD/LD, but wife denies any previous dream enactment. There were vivid dreams. On review of medical history and systems, he had no exposure to neuroleptics–a major cause of drug-induced PD. He denied exposure to pesticides. He was drafted in Vietnam but was never in-country (agent orange exposure is known to cause Parkinsonism).
His examination is notable for the following negative symptoms:
- No orthostasis
- No tachyphemia
- No nystagmus
- No tremor at rest, posture, or with action
The following findings were abnormal:
- Mild-moderate hypophonia
- Moderate facial masking with lid retraction a procerus sign.
- Restriction of voluntary upgaze with a round-the-house sign (eyes kind of looking around as they make their way vertically)
- Impaired vertical optokinetic response
- Square wave jerks are present
- Mild retrocollis
- Axial > appendicular rigidity
- Moderate symmetric bradykinesia
- Gait is quite slow with decreased arm swing bilaterally. Steps are short and shuffling.
For those of you (like me) who don’t have much of a background in optokinetic nystagmus, I should show you what Dr. Mantri means by it. You can use a long red cloth that has alternating red and white stripes, or even a drum that has alternating dark and white stripes that you spin. Either way, the stripes are moved horizontally or vertically across the patient’s visual field at a…pretty slow rate. You should observe the slow phase, or smooth pursuit of the eye movements as they track the colored stripe, followed by the fast corrective saccades as the patient’s eyes move to the next stripe that has entered their field of vision. Normally, the eyes will saccade back to the next stripe without difficulty. However, in conditions like PSP,
the optokinetic response may be slowed in both eyes. This is not usually seen in PD like Dr. Mantri said. When you see asymmetric slowing of a lateral OKN response in patients, this should make you think of an internuclear ophthalmoplegia.
At this point, PSP seems to be mentioned quite a bit. And that’s what our patient ended up having. A brain MRI would confirm this with the classic hummingbird sign–indicative of the pattern of midbrain atrophy seen in this neurodegenerative condition.
On a final note, before the show wraps up, patients with PSP have poorer outcomes when compared to patients with idiopathic PD. The mean age of diagnosis for a patient with PSP is around 65, and most patients only live another 5-8 years. Therapy is often supportive, and patients will benefit from your care, even if there aren’t medications you can prescribe. For the remainder of the episode, we discuss treatment options for these patients and what experts have recommended as far as management.
- Hess CW and Okun MS. Diagnosing Parkinson Disease. Continuum (Minneap Minn). 2016;22:1047-63.
- Garbutt S, Riley DE, Kumar AN, Han Y, Harwood MR and Leigh RJ. Abnormalities of optokinetic nystagmus in progressive supranuclear palsy. Journal of neurology, neurosurgery, and psychiatry. 2004;75:1386-94.
- McFarland NR. Diagnostic Approach to Atypical Parkinsonian Syndromes. Continuum (Minneap Minn). 2016;22:1117-42.
- PW Brazis, Masdeu JC, Biller J. Localization in Clinical Neurology, 6th ed. 2011 Lippincott Williams and Wilkins.