eLetters

102 e-Letters

  • Insult to injured Montezuma...

    To the Editor

    With respect to the article entitled ‘Montezuma’s revenge’: neurological disorders in the returning traveller, the authors make an important point about the treatment of malaria: hopefully GPs and potential travellers in the UK are always extra-ordinarily careful about malaria prophylaxis.
    However, I believe it worth pointing out that the list of illnesses which may be acquired in certain countries is, unfortunately, simply wrong (Figure 1). The following infectious diseases are not found in South Africa:
    1. Relapsing fever (except described in penguins![1]).
    2. Plague.
    3. African sleeping sickness.
    Following successful treatment of the outbreak in Madagascar perhaps one should also note that the Western half of the United States is historically a region where plague is found (not mentioned by the authors)[2]. I appreciate that the list provided in the article is derived from another source, but I am sure the authors will agree on the importance of avoiding the promulgation of inaccurate information.
    Finally, despite what the authors may maintain, the correct treatment, if any, of cerebral neurocysticercosis does indeed continue to remain controversial, and adequate RCTs have not been performed[3][4]. Decisions on treatment may well need to be made on a case by case basis, and it is important that neurologists should be aware of the dearth of hard evidence concerning the treatment of neurocysticercosis.

    1 Yab...

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  • Re: Lumbar puncture on Direct Oral Anticoagulants (DOACs): a novel, emerging perspective

    We are very grateful to Dr Rota and colleagues for their interest in our guideline.

    In essence, we agree that international consensus on DOAC level measurement and cut-off levels would be welcome.

    The experience reported by Dr Rota and colleagues of their use of idarucizumab for emergency reversal of dabigatran prior to lumbar puncture is reassuring. Our guideline refers to the need to consult a haematologist prior to administration; however, a guideline is for guidance and we recognise that locally agreed protocols may vary. Likewise, the timings mentioned in the guideline relating to the safe reinitiation of DOACs are by necessity pragmatic. Further evidence in this area will of course be very welcome to further inform practice.

  • Lumbar puncture on Direct Oral Anticoagulants (DOACs): a novel, emerging perspective

    Dear Editor,
    We read the article by Dodd et al. (2018) [1] with great interest. The authors provide evidence-based recommendations for the periprocedural management of antithrombotic and anticoagulant treatment in patients who require a lumbar puncture (LP). Indeed, this is a very relevant practical point for neurologists, above all when an urgent diagnostic LP is mandatory to rule out an infectious disease of the central nervous system, or a subarachnoid hemorrhage. The recommendations on adjustment/reversal of warfarin for patients on oral anticoagulants, who require LP, are well known, i.e. long-term LP allowed if INR is < 1.4. Whilst the question of how to manage patients on Direct Oral Anticoagulants (DOACS), a relatively novel pharmacological class, is also to be answered. Dodd et al’s article [1] reports that if a non-urgent LP has to be carried out he these patients, current recommendations vary among different advisory bodies about the time lapse necessary for DOAC withdrawal before the LP, depending on the renal function. The interesting possibility of measuring the drug-specific levels, so as to estimate the anticoagulant effect of a DOAC, is also mentioned, although the authors are of the opinion that routine testing before the LP is not necessary. [1]
    We believe that this is a crucial point, above all in the case of an urgent or emergent LP. Indeed, in our experience, when available, drug-specific levels can be obtained quickly and guide the cl...

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  • Ankle jerks

    Sir,
    I thoroughly enjoyed reading Dr. Allen’s excellent paper on the right way to do the ankle jerk. He is quite right in saying that ‘tendon reflexes’ are not tendon reflexes. Tapping a tendon leads to stimulation of the Golgi tendon organs, which are actually inhibitory to the alpha neurones, so no response should occur. The muscle contraction probably results from the vibrations transmitted to the intrafusal muscle fibres, leading to activation of the anterior horn cells and thus causing muscle contraction in response to the stimulus. The term “deep tendon reflex” is completely inappropriate; which deep tendons can one access? Levator palpebrae superioris? Piriformis? Gluteus medius? The tendons percussed have to be superficial so that we can get at them.

    Although Dr. Allen’s method is absolutely appropriate in patients who are confined to bed, those patients who are mobile can, I suggest, be better examined if you ask them first to kneel on the seat of the chair on which they were sitting, grasping its back with their hands. They are thus unconsciously performing a Jendrassik manoeuvre, augmenting any response that their bodies might make. Their ankles, projected out behind the seat, can be tapped easily, and the response noted with equal facility.

    Now in my 80s, I cannot remember whether it was Erb or Westphal or Romberg or somebody else who first suggested this method; but after 55 years in Neurology, I still find it the best way to asse...

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  • Reply to Graham Warner’s e-letter
    It is interesting that Graham Warner mentions the sound of absent ankle reflexes. I remember discussing the thud of an absent ankle with Michael Harrison, who was my greatest clinical guru, when I was his registrar at the Middlesex Hospital in London. I have also mentioned it to my students but tended to get the l look back that tells me politely that I might not come from the same planet as them. I suspect this is because learning to examine patients involves learning novel complex perceptions. Much of this is honed over many years and like all complex perceptions involves more than one sensory modality. As neurologists, we all know that appreciating a subtle flavour involves lot more than the sensory information from the tongue; it is mostly olfactory but also involves texture and temperature as well as context and expectation. This is why to many of us the discussions of wine buffs about the subtle flavours of different vintages sound like the ramblings of someone from an alien world. Thus when teaching students one has to realise that they are learning complex perceptions in unfamiliar contexts and may not be able to appreciate subtleties such as the sound of reflexes. So their “what planet is he from?” look is appropriate because perceptually they are in a different world to that of an experienced clinician. As teachers, we need to guide them to our world of complex perceptions and not all can follow, just as I would never succeed as a wine-taster (not that I don’t like...Show More
  • Reflection on reflexes

    Chris Allen’s series on neurological examination offers huge relief to fellow experts who execute it incorrectly, such as the “ankle jerks”. I too use the plantar method although caution Juniors/Students to do it the right way (tendon method) when non-neurologists assess in osce’s/finals. But in teaching them how to tick the boxes I have questioned why I do what I do (self-questioning being one of the reasons I seize the opportunity to train others). I then recall as an SHO Simon Nurick (one of the people who inspired me) tellinging me to listen to the reflexes, in that when absent one hears a dull thud (rather like that of a pleural effusion, so it is interesting to learn that neurological hammers evolved from those used for respiratory examination). And it sounds more resonant when present, all akin to how taught a violin string might be, I tell them. In fact not only do I listen, as well as observe (visual observation is all that generalists teach Medical Students), but also feel. I believe this most useful when the tension in the “strings” are greatest in hypertonic such that there may be no apparent movement nor sound, but one gets tactile feed back. Hence where possible I always strike the hammer against my own hand placed carefully to achieve best transmission of the force. I suspect all “experts” draw the greater data without knowing and can so better analyse the clinical situation.
    I’m confident too that they like me may even apply varying non-standard force...

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  • Pure Autonomic Failure: the importance of waiting to confirm the diagnosis

    Dear Editor,
    Thomas Brown provided a helpful recent review of pure autonomic failure (PAF) in this journal1. However, there is one very important point which I would wish to add. The diagnosis of this rare condition should be made with extreme caution in the early years of presentation. The first case in the review had a diagnosis of PAF made just two years after symptoms began. In fact, other commoner causes of primary autonomic failure may declare themselves many years after the symptoms first begin, and I have seen a number of such cases during my time at the autonomic unit in Queen Square. A rough rule of thumb used to be that at least five years should pass before making a definitive diagnosis of PAF2. More recent evidence suggests that even longer may be required. A third of cases already with symptoms suggestive of PAF for an average of 5 years were found to have an alternative diagnosis with subsequent follow up for a further four years3. Alternative diagnoses included other synucleinopathies such as Parkinson’s disease, dementia with Lewy bodies or multiple system atrophy.
    For many years attempts have been made to find reliable ways to distinguish PAF from other causes of primary autonomic failure. PAF is seen classically as a post-ganglionic disorder whilst multiple system atrophy is seen as a pre-ganglionic form of primary autonomic failure. Utilising this pathophysiological difference, a variety of differentiating tests have been attempted....

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  • SUDEP: The thing we fear more than death

    We came across the pages of the article of Nashef and Leach recently released to the scientific community through the Practice Neurology with a great enthusiasm.1 The authors have not only had courage, but have had special ability in touching on such an important matter in a scientific and subtle manner simultaneously. As we know, along the past twenty years there has been exponential growth in the number of articles published on SUDEP with a triple increase in this scientific production in the last ten years.2 Therefore a great scientific breakthrough in SUDEP has been established with regard to epidemiological aspects, specific risk factors, mechanisms involved and possible preventive measures (if they really exist) 3. And yet, it is very well defined that the main risk factor for SUDEP is the presence and number of generalized tonic-clonic seizures (GTCS)3 and the best way to avoid a tragic event is to control these GTCS. In parallel, there is also an imperative issue in relation to all these aspects: how, when, where, why and what patients should we address on SUDEP? Despite the great effort of epileptologists and elegant studies already published, the discussion on SUDEP with patients is still a matter of debate among experts.4 In order to enable this debate, we will have to somehow let the conservative side and consider the current numbers that demonstrate that 1 in every 1000 young adults and 1 in every 4500 children with epilepsy may suddenly die. 5 And more, accor...

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  • ‘Organic’ and ‘non-organic’

    Stone and Carson(1) say:
    ‘Non-organic refers to things unrelated to living matter,… This is a word that cannot be used to describe conditions suffered by living human beings.’ They refer ‘to the OED sense: “something characterised by structural or other pathological change in an organ or organs”. They acknowledge it was useful ‘in the 19th century when neurologists first saw the pathology of multiple sclerosis or motor neurone disease. But what about genetic generalised epilepsy or migraine—pathological, but not necessarily structural, or at least no more so than, for example, unipolar depression where there is quite substantial evidence for structural changes. ’(2)

    They are right to point out the difficulties in separating ‘functional and non-organic’ disorders from those with structural or ultrastructural abnormalities but they should not be ‘blackballed from the club of legitimate conditions because of the difficulty in establishing their veracity.’

    Most of us understand that epilepsy, migraine and spasmodic torticollis, for example, have underlying structural or other subtle abnormalities; the fact that modern techniques don't always disclose the organic basis does not mean they are psychogenic, do not exist, or are illegitimate.

    Functional was originally the result of altered function (rather than structure) of an organ, system, etc.; but its meaning confusingly changed to a psychological cause as opposed to a physical one. The term...

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  • Authors response to Dr Hughes' comments

    We thank Dr Hughes for his thoughtful letter and his previous extensive comments as part of the reviewing process.

    The main issue Dr Hughes has raised is the possibility of another local structural lesion. He asks that “Some cross checking with digital examination of the floor of the mouth, palpation of the tongue, or the results of attempts by a clinician to correct the position of the tongue may be all that is required to confirm or refute the working diagnosis.

    We had already addressed this in our paper “The ENT and oral maxillofacial surgeons had noted a small post-traumatic neuroma/granuloma at the left retromolar space but with no other oral structural abnormality “. And expanded on this in response to the query in Dr Hughes’s first review, “No structural lesion to the tongue muscle or its attachments was observed on clinical examination by an experienced ENT surgeon or on independent examination by an oral maxillofacial surgeon”.

    We feel our explanation as outlined in our paper remains the most plausible.

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