On the seizure-detecting instincts of pets

Like something from a futuristic medical thriller, you have mice diagnosing bladder tumours, and dogs detecting prostate cancer, just by sniffing the urine of patients. And like a plot from a Sci-Fi film, dogs are also trained to smell-out malaria. But we are not forward to the future – we are still in the here and now. And it is not just cats, dogs, and mice; pouched rats and nematodes have staked their claim as well. And the number of diseases that pets can presumably detect grows longer by the day (OK perhaps by the year), and these range from diabetic hypoglycaemia, colorectal cancer and migraine, to infections such as Clostridium difficile and tuberculosis. And whilst there are many animals in on the act, they are just bit players on this set – dogs are by far the superstars of the show.

Baxter gives me the sniff test. VirtKitty on Flickr. https://www.flickr.com/photos/lalouque/3881459268/

As weird as it may sound, many of the reports being anecdotal, there are actually grains of truth and crumbs of evidence supporting the claim that pets are not just for Christmas. For example, there is a trail of research studies confirming the effectiveness of seizure detecting dogs; one paper specifically reports that they enabled 90% of subjects to reduce their seizure frequency by 34-50%. Although the time from seizure-detection to the actually seizure varies wildly, from 10 seconds to 5 hours before the epileptic attack, there seems to be enough time in most cases for the subject to take preventative measures.

Roger Hiorns’ Seizure. Hilary Perkins on Flickr. https://www.flickr.com/photos/cowbite/3781509099

But not all dogs are as skilled in the act as others, and your best bet is on alerting dogs which have a stronger bond with their owners. And if you want to pick a dog for its seizure-detecting skills, go for one that scores high in motivation…and low in neuroticism. This is important because the ability of dogs to detect seizures is not always benign; they are known to respond by attacking the subject or their helpers as part of an untrained fight or flight reaction. It is important therefore that seizure-alerting dogs are trained not to be stressed, and to respond appropriately.

Beware of the angry dog. Julija Rauluševičiūtė on Flickr. https://www.flickr.com/photos/cowbite/3781509099

But what are dogs actually detecting when they detect seizures? The conventional theory is that they are responding to subtle changes in behaviour; this may therefore explain why dogs can also warn of impending non-epileptic attacks, an observation that has been duplicated in another paper. The other possibility however is that the dogs are detecting disease-specific odours. This concept should not be surprising because, for example with infections, it has been shown that endotoxins induce a detectable aversive body odour. Similarly with liver disease, exhaled breath is already being considered in sorting out differential diagnoses. One premise behind the disease-odour hypothesis is the existence of disease-specific volatile organic compounds (VOCs). It feels all so exciting-no wonder there is now a well-developed scientific field of exhaled air analytics.

Breath. Andrea Castelletti on Flickr. https://www.flickr.com/photos/daltraparte/3050309593

But as with all things in life, and particularly in science, here are always the naysayers, the gatecrashers to the party. And so it is that, with the case of seizures, there are those who are not convinced that pets possess the guile to pick up seizures. For example, in a small study of 3 subjects in an epilepsy monitoring unit, Rafael Ortiz and Joyce Liporace, reporting in the journal Epilepsy and Behaviour, found that seizure alert dogs were not effective in predicting seizures. In another paper  published in the journal Epilepsy Research, titled Can seizure-alert dogs predict seizures?, Stephen Brown and Laura Goldstein observed that there is “no rigorous data” to support the assertion that seizure alert dogs accurately predict seizures. Another detailed review in Plos One in 2018, by Amélie Catala and colleagues, concluded that appropriate empirical evidence that dogs can alert or respond to epileptic seizures is still missing

By https://wellcomeimages.org/indexplus/obf_images/3c/f4/5188f74ad62c7b5634b55047ac5d.jpgGallery: https://wellcomeimages.org/indexplus/image/V0016630.htmlWellcome Collection gallery (2018-03-23): https://wellcomecollection.org/works/kbcqbc43 CC-BY-4.0, CC BY 4.0, Link

 

But as the overused cliché goes, absence of evidence is not the evidence of absence. So how can we prove that dogs are indeed detecting seizure-specific odours? This is the task Amélie Catala and her colleagues also set out to accomplish when they made 5 dogs to sniff the odours obtained from 5 people with epilepsy. They tasked the dogs to tell apart the odours obtained around the time of the subjects’ seizures, from the odours obtained at other times when there were no proximate seizures. Reporting their findings in Science Report in 2019, under the title Dogs demonstrate the existence of an epileptic seizure odour in humans, they found that all the 5 dogs easily distinguished the seizure-related odours from the non-seizure related odours. But the small scale of the trial (were there just not enough dogs to go round?) justifies the authors’ call for larger trials to confirm their findings.

 

Big Nose Strikes Again. Bazusa on Flikr. https://www.flickr.com/photos/bazusa/260401471

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This is clearly still a grey area in epilepsy management, but one with a high potential if explored further. Are there any pet-loving neurologists willing to get in on the act? Do come along with your pets!

25 non-eponymous neurological disorders… and the names behind them

Medicine is as much defined by diseases as by the people who named them. Neurology particularly has a proud history of eponymous disorders which I discussed in my other neurology blog, Neurochecklists Updates, with the title 45 neurological disorders with unusual EPONYMS in neurochecklists. In many cases, it is a no brainer that Benjamin Duchenne described Duchenne muscular dystrophy, Charle’s Bell is linked to Bell’s palsy, Guido Werdnig and Johann Hoffmann have Werdnig-Hoffmann disease named after them. Similarly, Sergei Korsakoff described Korsakoff’s psychosis, Adolf Wellenberg defined Wellenberg’s syndrome, and it is Augusta Dejerine Klumpke who discerned Klumpke’s paralysis. The same applies to neurological clinical signs, with Moritz Romberg and Romberg’s sign, Henreich Rinne and Rinne’s test, Jules Babinski and Babinski sign, and Joseph Brudzinski with Brudzinki’s sign.

Yes, it could become rather tiresome. But not when it comes to diseases which, for some reason, never had any names attached to them. Whilst we can celebrate Huntington, Alzheimer, Parkinson, and Friedreich, who defined narcolepsy and delirium tremens? This blog is therefore a chance to celebrate the lesser known history of neurology, and to inject some fairness into the name game. Here then are 25 non-eponymous neurological diseases and the people who discovered, fully described, or named them.

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Amyotrophic lateral sclerosis (ALS)

Jean-Martin Charcot

Készítette: Unidentified photographerhttp://resource.nlm.nih.gov/101425121, Közkincs, Hivatkozás

Aphantasia

Francis Galton (and Adam Zeman)

By Eveleen Myers (née Tennant) – http://www.npg.org.uk/collections/search/portrait/mw127193, Public Domain, Link

Chronic inflammatory demyelinating polyneuropathy (CIDP)

Peter J Dyck

By Dr. Jana – http://docjana.com/#/saltatory ; https://www.patreon.com/posts/4374048, CC BY 4.0, Link

Corticobasal degeneration (CBD)

WRG Gibb, PJ Luthert, C David Marsden

https://upload.wikimedia.org/wikipedia/commons/c/cd/ProteineTau.jpg

Epilepsy

Hippocrates

Hippocrates. Eden, Janine and Jim on Flickr. https://www.flickr.com/photos/edenpictures/8278213840

Essential tremor

Pietro Burresi

By UndescribedOwn work, CC BY-SA 4.0, Link

Frontotemporal dementia (FTD)

Arnold Pick

By Unknown authorhttp://www.uic.edu/depts/mcne/founders/page0073.html, Public Domain, Link

Inclusion body myositis (IBM)

E J Yunis and F J Samaha

CC BY-SA 3.0, Link

Meningitis

Vladimir Kernig and Jozef Brudzinski

By A. F. Dressler – Festschrift zum 70. Geburtstag Dr. Woldemar Kernig’s: Von Verehrern und Schülern herausgegeben als Festnummer der St. Petersburger medicinischen Wochenschrift St. Petersburger medizinische Wochenschrift, Bd. 35, Nr. 45. (1910), Public Domain, Link

Migraine

Aretaeus of Cappadocia

By Cesaree01Own work, CC BY-SA 4.0, Link

Multiple sclerosis (MS)

Jean-Martin Charcot

Journal.pone.0057573.g005http://www.plosone.org/article/info:doi/10.1371/journal.pone.0057573#pone-0057573-g005. Licensed under CC BY 2.5 via Wikimedia Commons.

Multiple system atrophy (MSA)

Milton Shy and Glen Drager

By Kenneth J. Nichols,Brandon Chen, Maria B. Tomas, and Christopher J. Palestro – Kenneth J. Nichols et al. 2018. Interpreting 123I–ioflupane dopamine transporter scans using hybrid scores., CC BY 4.0, Link

Myasthenia gravis (MG)

Samuel Wilks

By Unknown authorhttp://ihm.nlm.nih.gov/images/B25782, Public Domain, Link 

Myotonic dystrophy

Hans Gustav Wilhelm Steinert

By Unknown author – reprinted in [1], Public Domain, Link 

Neurofibromatosis

Friedreich Daniel von Recklighausen

By Unknown authorIHM, Public Domain, Link 

Narcolepsy

Jean-Baptiste-Edouard Gélineau

https://upload.wikimedia.org/wikipedia/commons/7/74/Jean_Baptiste_Edouard_G%C3%A9lineau.jpg

Poliomyelitis

Michael Underwood

By Manuel Almagro RivasOwn work, CC BY-SA 4.0, Link

Progressive supranuclear palsy (PSP)

John Steele, John Richardson, and Jerzy Olszewski

By Dr Laughlin Dawes – radpod.org, CC BY 3.0, Link

Restless legs syndrome (RLS)

Karl Axel Ekbom

By Peter McDermott, CC BY-SA 2.0, Link

Stiff person syndrome (SPS)

Frederick Moersch and Henry Woltmann

By PecatumOwn work, CC BY-SA 4.0, Link

Synesthesia

Georg Sachs and Gustav Feschner

Synaesthesia. aka Tman on Flickr. https://www.flickr.com/photos/rundwolf/7001467111/

Stroke

Hippocrates

By editShazia Mirza and Sankalp GokhaleSee also source article for additional image creators. – editShazia Mirza and Sankalp Gokhale (2016-07-25). Neuroimaging in Acute Stroke.Attribution 4.0 International (CC BY 4.0), CC BY 4.0, Link

Tabes dorsalis

Moritz Romberg

By https://wellcomeimages.org/indexplus/obf_images/39/1d/edecf5a530781f5c10603a50fa35.jpghttps://wellcomecollection.org/works/gctr3stg CC-BY-4.0, CC BY 4.0, Link

Trigeminal neuralgia

John Fothergill

By Gilbert Stuarthttp://www.pafa.org/Museum/The-Collection-Greenfield-American-Art-Resource/Tour-the-Collection/Category/Collection-Detail/985/mkey–1923/, Public Domain, Link

Tuberous sclerosis

Désiré-Magloire Bourneville

By Unknown author – Bibliothèque Interuniversitaire de Médecine – http://www.bium.univ-paris5.fr/images/banque/zoom/CIPB0452.jpg, Public Domain, Link

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Reunion of neurologists at the Salpêtrière hospital. Photograph, 1926 https://commons.wikimedia.org/w/index.php?curid=36322408

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Let us then celebrate the pioneers…

Eponymous and anonymous alike