Paraneoplastic, Neoplastic, and Paraproteinemic Polyneuropathy

Name: Paraneoplastic, Neoplastic, and Paraproteinemic Polyneuropathy
Uploaded: 2022-05-05
Duration: 6 min 14 s
Description: The lecture Paraneoplastic, Neoplastic, and Paraproteinemic Polyneuropathy by Roy Strowd, MD is from the course Other Non-inflammatory Neuropathies.

by Roy Strowd, MD

Ask Questions

Take Notes

Download Slides

Report Mistake

Comments

show all Show less

My Notes

show all

Learning Material 2

PDF

Slides Other Non-inflammatory Neuropathies.pdf
PDF

Download Lecture Overview

show all

Report mistake

Transcript

00:00 Now let's talk about some of the paraneoplastic or paraproteinemic neuropathies. We see two broad categories of cancer or cancer-associated conditions that can cause neuropathy. The first are the paraproteinemias. These are disorders like multiple myeloma, monoclonal gammopathy of undetermined significance, Waldenstrom's macroglobulinemia, and lymphoid or lymphomatous neuropathy and that is infiltration of the nerves from lymphoma or neurolymphomatosis. In addition, we can see paraneoplastic etiologies where there is an underlying cancer that is revved up the immune system and the immune system is attacking the nerves. And the most common and classic presentation is anti-Hu antibody syndrome, which presents with a prominent sensory ganglionopathy. Let's talk about a couple of these conditions and start with anti-Hu antibody polyneuropathy. This is a sensory predominant polyneuropathy associated with systemic anti-Hu antibodies, and it results in a sensory ganglionapathy. Patients have predominant sensory symptoms in the absence of motor symptoms. Importantly, the sensory afferents are important in the reflex arc. So we do see reduced or absent deep tendon reflexes with a predominance of sensory abnormalities with normal motor strength. Some important presentations of anti-Hu antibody polyneuropathy include a pure sensory ganglionopathy, this is associated with small cell lung cancer, somewhere around 25% of patients with small cell lung cancer will develop anti-Hu antibodies, and in a subset of those patients they will become pathologic and result in damage to the sensory ganglion the dorsal root ganglion, presenting with prominent vibration proprioception and in some cases pain and temperature dysfunction as well as light touch a sensory ganglionopathy. The second presentation is a sensorimotor polyneuropathy. Patients have sensory predominance but there is associated motor findings on EMG nerve conduction study or on clinical exam. And then the last, we can see a sensory ataxic neuropathy where patients have severe proprioceptive loss to the point that there is prominent sensory ataxia. They do not know where their fingers are in space, a sensory choreoathetosis, where the fingers will move on their own can occur and significant difficulty with dysmetria and coordination of both the appendicular function and truncal coordination. To make a diagnosis of anti-Hu antibody polyneuropathy and other paraneoplastic polyneuropathies, the LP is critically important. We're looking for evidence of inflammation, elevated protein often with normal cell counts no pleocytosis. And we do antibody testing looking for those paraneoplastic antibodies, including the anti-Hu antibody. To look for paraneoplastic antibodies, we often start our diagnostic investigation in the serum. These are antibodies, they circulate around in the serum before gaining access to the nerve, the spinal fluid or other parts of the nervous system. But we can do CSF testing, particularly when serum testing is negative. And the presence in the CSF of a paraneoplastic antibody is essentially diagnostic of an underlying pathologic process. When we treat these patients, we're managing the immune system. So there's two parts in managing a paraneoplastic process. The first is to treat the underlying cancer, that's the nidus for revving up the immune system, the activation of the immune system. And by treating the cancer, we remove that stimulus of the immune system. While patients are undergoing cancer treatment or at the initial presentation or in patients where the cancer is unable to be treated. We think about immunomodulating therapy suppressing the immune system so that the immune response and attack on the nerves is subsided. IV steroids methylprednisolone as well as IVIG and plasmapheresis can be used in those settings. Now let's talk about some of the paraproteinemic polyneuropathies. These are polyneuropathies occurring in patients with a paraproteinemia. We see neuropathy with an increased M-spike or an increased in a monoclonal paraprotein that can occur in multiple myeloma which is a plasma cell disorder with monoclonal gammopathy of undetermined significance, or Waldenstrom's macroglobulinemia. In these patients, we're looking for an elevation in a pair of protein or an M-spike either in the blood or urine, which would warrant further hematologic evaluation in these patients. Neuropathy is a common presenting symptom. And so sometimes neuropathy is the first sign of an underlying paraproteinemia that would require further evaluation and potentially management. The etiology and pathophysiology of the paraproteinemic neuropathies is increased protein. As a result of this increase in immunoglobulins, which is composed of a heavy and light chain, we see increased protein circulating in the blood. This can cause deposition in small vascular beds, we can see kidney dysfunction, as well as deposition of proteins in the nervorum, the small vascular beds around the nerve, and this can result in neuropathy in these patients. Though a differential diagnosis for a paraproteinemic neuropathy includes POEMS: Polyneuropathy, Endocrinopathy, Ophthalmoplegia, M-spike and skin findings, that's a patient with neuropathy with an M-spike. But the presence of these other organ involvements would point towards POEMS, as opposed to an underlying multiple myeloma or MGUS. Neuropathy with M-spike can be seen. Lymphomatous neuropathy is a neuropathic condition where we can see an M-spike and maybe similar to Waldenstrom's as well as amyloid neuropathy, cryoglobulinemia. These are all conditions where patients present with neuropathy in association with M-spike and our diagnostic work up should include evaluation of these conditions.

About the Lecture

The lecture Paraneoplastic, Neoplastic, and Paraproteinemic Polyneuropathy by Roy Strowd, MD is from the course Other Non-inflammatory Neuropathies.

Included Quiz Questions

Which of the following laboratory findings would be consistent with a paraneoplastic polyneuropathy?

Anti-Hu antibodies in the CSF
Numerous WBCs in the CSF
M spike in the urine
M spike in the blood
Glucosuria

Which finding is most likely to be seen with a polyneuropathy associated with small cell lung cancer?

Prominent vibration and proprioception dysfunction
Prominent sensory ataxia
Ascending flaccid paralysis
Prominent motor dysfunction with multifocal sensory loss
Unilateral upper extremity sensory loss

Which of the following conditions is most likely to cause polyneuropathy associated with a serum M spike?

Amyloidosis
Diabetes mellitus
HIV
Cirrhosis
Campylobacter infection

Author of lecture Paraneoplastic, Neoplastic, and Paraproteinemic Polyneuropathy

Roy Strowd, MD

Customer reviews

(1)
5,0 of 5 stars

5 Stars		5
4 Stars		0
3 Stars		0
2 Stars		0
1 Star		0

Playlist

Show Playlist

Hide Playlist