New Study: Pain in HNPP: An Association with Fibromyalgia Syndrome

I think this study is very important, and raises many questions about HNPP, the diagnosis rates, misdiagnosis, and how pain in HNPP has been left unreported over the years due to ascertainment bias, and by poor diagnostic criteria.

Unfortunately, like so many abstracts found on PUBMED, the full article is only available on payment of a pay-per-view fee, or by subscription to the journal in question. However, our great and wonderful neurologists (in the UK) should have access to all these articles via the Athens/Ovid database, and being NHS employees this should mean that all articles should be viewable free of charge. So there really should be no excuse for our neurologists not to read this article.

Although the title suggests a link between HNPP and FMS, the summarised discussion seems to suggest that in the authors opinion that HNPP is being misdiagnosed as FMS, especially in cases where the pain reported is mostly musculoskeletal.

It is also significant that these authors have fully accepted that pain, both neuropathic , Musculoskeletal or mixed can be an initial presentation of HNPP. It is also clear that with acceptance of pain as one of the initial symptoms, then one would expect diagnostic rates to improve.

Doctors who maintain that HNPP does not cause pain, and only look for painless pressure palsies appear to have a very poor diagnostic rate for HNPP. Estimates suggest that this is around 15-20% of the predicted figure for HNPP, in comparison with CMT1a incidence rates.

There is probably much more that can be discussed from this study, a full copy would enhance that greatly, I just hope some of our esteemed neurologists make the effort to read this. Sarcasm intended and implied.

Edit: I’ve just remembered something else about this study that I felt was quite significant. When looking at the numbers of those who had pain as a symptom and those who had pain as an initial symptom, the figures appear to be in the region of 79% of the sample group. Which as it happens tallies fairly well with Pain and HNPP polls taken on the onlne support groups, actually it’s a bit lower but support groups might have a slightly skewed group sample. But the figures are very similar, suggesting the the online group polls are representative of HNPP as a whole.



1. Muscle Nerve. 2014 Jul 5. doi: 10.1002/mus.24331. [Epub ahead of print]

Pain in hereditary neuropathy with liability to pressure palsy: An association
with fibromyalgia syndrome?

Yilmaz U(1), Bird TT, Carter GT, Wang LH, Weiss MD.

Author information:
(1)Department of Neurology, University of Washington School of Medicine, Seattle,

INTRODUCTION: This study characterizes the nature of pain in hereditary
neuropathy with liability to pressure palsy (HNPP).
METHODS: This retrospective study was performed to assess duration, nature,
location, and intensity of pain on initial presentation of subjects with HNPP,
including the degree and type of analgesic medication use and electrodiagnostic
characteristics. Subjects who met the American College of Rheumatology criteria
for fibromyalgia syndrome (FMS) were also identified.
RESULTS: Of 32 HNPP subjects, 24 (75%) had symptoms of pain, and 4 (12%) had pain
as an initial symptom. Of subjects who described pain, 9 (28%) reported only
musculoskeletal pain, 10 (31%) only neuropathic pain, and 5 (16%) both
musculoskeletal and neuropathic pain. All 9 subjects with only musculoskeletal
pain met criteria for FMS.
DISCUSSION: Neuropathic and musculoskeletal pain occur commonly in HNPP and may
be a presenting symptom. Additionally, HNPP with predominantly musculoskeletal
pain may meet criteria for FMS and potentially delay the diagnosis. © 2014 Wiley
Periodicals, Inc.

Copyright © 2014 Wiley Periodicals, Inc., a Wiley company.

PMID: 25042093 [PubMed – as supplied by publisher]




Leave a Reply

Fill in your details below or click an icon to log in: Logo

You are commenting using your account. Log Out /  Change )

Google+ photo

You are commenting using your Google+ account. Log Out /  Change )

Twitter picture

You are commenting using your Twitter account. Log Out /  Change )

Facebook photo

You are commenting using your Facebook account. Log Out /  Change )


Connecting to %s