I read with interest the debate between Nightingale el al. and Schott
about whether we should routinely test for HIV in patients presenting with
cognitive impairment 1,2 . I assume that while the authors have taken
rather polarized views to state their point, the correct answer lies
somewhere in between. Testing for HIV shall not be the foremost in my
mind in a 75-year-old male presenting with slowly progressive cognitive...
I read with interest the debate between Nightingale el al. and Schott
about whether we should routinely test for HIV in patients presenting with
cognitive impairment 1,2 . I assume that while the authors have taken
rather polarized views to state their point, the correct answer lies
somewhere in between. Testing for HIV shall not be the foremost in my
mind in a 75-year-old male presenting with slowly progressive cognitive
impairment for the past few years accompanied with typical features of a
cortical dementia (aphasia, apraxias and agnosias). In such a patient I
shall rather harness my clinical and diagnostic skills to differentiate
between Alzheimer's disease, frontotemporal dementia and Lewy body
dementia. On the other hand a 45-year-old male presenting with cognitive
impairment accompanied by a movement disorder, certainly HIV testing shall
be included in my diagnostic armamentarium. One must though not forget
that positive HIV serology is not synonymous with HIV encephalopathy or
AIDS dementia complex which is a clinical syndrome comprising of a
combination of cognitive, behavioral and motor dysfunction. Testing a
patient with cognitive impairment for HIV shall have a high positive
predictive value only when the test is carried out after taking the
patient's age at presentation, history (not just of risk factors but also
of the rate of progression of symptoms) and examination findings into
consideration.
References
1. Nightingale S, Michael BD, Defres S, Benjamin LA, Solomon T. Test
them all; an easily diagnosed and readily treatable cause of dementia with
life-threatening consequences if missed. Pract Neurol. 2013;13:354-6.
2. Schott JM. HIV testing in dementia: test some, perhaps more, but
not all. Pract Neurol. 2013;13:357-8.
Can myoclonus involve large muscles like the trunk muscles giving out
just one jerk with a duration of a fraction of a second?Would it be
justified to term this phenomena as a myoclonic seizure or a complex
myoclonus when there is LOC for that fraction of a second;happening while
falling asleep only.Or can it be a sleep disorder,a hypnic jerk?
Can myoclonus involve large muscles like the trunk muscles giving out
just one jerk with a duration of a fraction of a second?Would it be
justified to term this phenomena as a myoclonic seizure or a complex
myoclonus when there is LOC for that fraction of a second;happening while
falling asleep only.Or can it be a sleep disorder,a hypnic jerk?
Conflict of Interest:
without reading the entire text how can I declare any competing interests.
We welcome the article by Jones et al, and in particular the chance
to compare the protocol used in their institution with the one we hope to
implement (1).
In Northern Ireland, we are in the process of drawing up a regional
protocol for the management of status epilepticus, due to wide variation
in current practice. We carried out preliminary work to see where the gaps
in knowledge are, so that we can create a...
We welcome the article by Jones et al, and in particular the chance
to compare the protocol used in their institution with the one we hope to
implement (1).
In Northern Ireland, we are in the process of drawing up a regional
protocol for the management of status epilepticus, due to wide variation
in current practice. We carried out preliminary work to see where the gaps
in knowledge are, so that we can create a relevant protocol to assist
junior staff, hopefully highlighting the need for a protocol.
We surveyed post finals - final year medical students (9 students)
foundation (28 doctors) and core medical trainees (24 doctors) and got 61
responses to a questionnaire (~85% returns). Only 10% of these knew the
appropriate dose and rate of administration of two first line drugs.
Only 54% would have given an initial 4 mg dose of lorazepam, and only
36% knew the correct dose of phenytoin (15-20mg/kg); 44% acknowledged they
were unaware of the dose. One third knew the appropriate initial infusion
rate of phenytoin.
Knowledge of the side effects of phenytoin was generally good,
although worryingly 30% thought sedation was a side effect of phenytoin,
which might lead to complacency in managing the apparently "post ictal"
patient.
It was also evident that a significant issue for junior doctors is
making the actual diagnosis of status epilepticus. Without clinical
experience junior doctors lack ability in making a confident and accurate
diagnosis, for which they are prepared to give drugs which are sedating
and are perceived to be potentially dangerous. In addition doctors in the
early stages of training had limited appreciation of potentially
discriminant features such as back arching, biting the tip of the tongue,
open eyes during the event and the synchrony of limb movements, in making
a clinical diagnosis of seizure versus non epileptic attack disorder.
Better educational strategies that inform, everyone who manages
status epilepticus, about seizure semiology (2) would go hand in hand
with dissemination of treatment protocols and would therefore be useful.
We wish to add another vitally important point to the protocol by
Jones et al, and that is the clear instruction to seek immediate urgent
advice from the nearest neurology service in all cases of status
epilepticus.
(1) Jones S, Pahl C, Trinka E, et al. A protocol for the inhospital
emergency drug management of convulsive status epilepticus in adults.
Practical neurology 2014;14:194-197
(2) Seneviratne U, Ding C, Bower S et al. Video based training
improves the accuracy of seizure diagnosis. J Neurol Neurosurg Psychiatry
2014;85:466-470
We thank Dr Lilleker for his comments. We agree that use of PCP
prophylaxis must provide benefit that would outweigh any attendant risk.
As suggested in our article, this risk is likely to vary depending on the
dose and duration of steroid therapy, the co-administration of other
biologicals and the systemic health of the patient. A patient with e.g.,
systemic vasculitis-associated mononeuritis multiplex who has also b...
We thank Dr Lilleker for his comments. We agree that use of PCP
prophylaxis must provide benefit that would outweigh any attendant risk.
As suggested in our article, this risk is likely to vary depending on the
dose and duration of steroid therapy, the co-administration of other
biologicals and the systemic health of the patient. A patient with e.g.,
systemic vasculitis-associated mononeuritis multiplex who has also been
treated with cyclophosphamide is likely to be at much higher risk than in
the cited example of an individual with myasthenia. The potential
toxicity of trimethoprim-sulfamethoxazole may be augmented through use of
a lower 80/400mg daily dose; or through use of alternate day 160mg/800mg
dosing. Recent data from the field of rheumatology suggests that the
overall risks of prophylaxis are low and the prophylactic benefit high
[1].
Ultimately, we agree with the correspondent that knowledge of the
incidence for PCP in our immunosuppressed patients would best guide
application of such data in clinical practice. Since publication, others
have shared empiric experience of adverse outcomes in those not placed on
prophylaxis. Awaiting definitive data, the decision remains with the
individual clinician; taking into account the risk factor profile
mentioned above.
Reference
[1] Katsuyama T, Saito K, Kubo S, Nawata M, Tanaka Y. The prophylaxis for
Pneumocystis pneumonia in patients with rheumatoid arthritis treated with
biologics, based on risk factors found in a retrospective study. Arthritis
Res
Ther. 2014 Feb 5;16(1):R43. PubMed PMID: 24495443; PubMed
Central PMCID: PMC3978920.
I thank the authors for highlighting this difficult topic with a very
thought provoking article.
In immunosuppressing a patient with neurological disease, as with
anything a physician does to a patient, there are potential risks to take
into account and to be weighed up against the proposed benefits. Indeed,
this sort of "cost-benefit" analysis is a central tenant of decision
making in much of life outside of me...
I thank the authors for highlighting this difficult topic with a very
thought provoking article.
In immunosuppressing a patient with neurological disease, as with
anything a physician does to a patient, there are potential risks to take
into account and to be weighed up against the proposed benefits. Indeed,
this sort of "cost-benefit" analysis is a central tenant of decision
making in much of life outside of medicine also.
It is generally accepted that in order to proceed, the benefits
should outweigh the "costs". It is clear that PCP prophylaxis is effective
at reducing the incidence of PCP, but at what cost? In patients with solid
-organ transplant for example, this is fairly clear as the incidence
appears high, as noted in the authors references.
The problem is that we have little knowledge of the incidence of PCP
in patients immunosuppressed for myasthenia gravis, for example. My
personal feeling is that this risk is much lower, but there is little
evidence in the literature to support this.
When considering that around 15% of patients develop side effects
whilst taking trimethoprim-sulfamethoxazole, and these can (in rare cases)
be fatal, it is not clear in my mind that the cost-benefit analysis for
patients with neurological disease swings in favour of the widespread use
of PCP prophylaxis. Put simply, would enough cases of PCP be prevented to
outweigh the risks posed by the side effect profile of the medication?
To help us make this decision we need clearer data on the incidence
of PCP in patients with neurological diseases who are being prescribed
immunosuppressive medication.
This is a superb book that deserves to be better known, at least on
my side of the Atlantic. In addition to Barker's outstanding depiction of
WW1 Britain, the sympathetic and revealing exploration of the physician-
patient relationship is peerless. Interested readers should know that
Regeneration is the first book in a trilogy, though neither is quite as
good as Regeneration. The second book, The Eye in the Door, is qui...
This is a superb book that deserves to be better known, at least on
my side of the Atlantic. In addition to Barker's outstanding depiction of
WW1 Britain, the sympathetic and revealing exploration of the physician-
patient relationship is peerless. Interested readers should know that
Regeneration is the first book in a trilogy, though neither is quite as
good as Regeneration. The second book, The Eye in the Door, is quite
good. The final book, The Ghost Road, is a bit uneven but the final
section of this book, describing an infantry assault in the closing stages
of the war, is an absolute tour-de-force of sympathetic description.
In a paper published last year in the New England Journal of Medicine
(NEJM), Messerli noted "a surprisingly powerful correlation between
chocolate intake per capita and the number of Nobel laureates in various
countries," which he postulated as "most likely" related to the cognitive
enhancing benefits of chocolate.1 This article in one of the premier
journals in the world received extraordinary press reports around the t...
In a paper published last year in the New England Journal of Medicine
(NEJM), Messerli noted "a surprisingly powerful correlation between
chocolate intake per capita and the number of Nobel laureates in various
countries," which he postulated as "most likely" related to the cognitive
enhancing benefits of chocolate.1 This article in one of the premier
journals in the world received extraordinary press reports around the time
of its release including in television (BBC News, CBC) and print (Time,
Reuters, Associated Press, and Forbes) media.
We found substantial methodological and conceptual errors in the Messerli
article that we brought to the attention of the editor of the NEJM shortly
after its publication. However, much to our surprise and dismay, no letter
to the editor (including ours), note or article addressing these concerns
have appeared in the NEJM since publication of the original article,
although several authors have subsequently brought several statistical
criticisms to light in other journals,2-5 including Practical Neurology.
While several authors who have criticized the Messerli article have done a
wonderful job of highlighting the limitations of association studies, no
one, to date, has addressed two issues we feel are even more important to
the scientific process: 1. Messerli's use of secondary sources (i.e.,
Wikipedia) for his data and 2. Messerli's selective use of data to support
his hypothesis.
In his article, Messerli notes, correlation does not "prove" causation and
he notes he lacks the specific chocolate intake of individual Nobel
Laureates. However, correlation between 2 variables is frequently used for
hypothesis generation and Messerli suggests several hypotheses to account
for his correlation.
First, hypotheses generated from data are, of course, no better than the
data on which they are based. Therefore, it is essential that authors use
primary sources when possible. Messerli used data on Nobel laureates from
Wikipedia6, which were based upon a BBC source, instead of data obtained
directly from the Nobel Prize website7 which is readily available. The
distinction is important and changes the resultant number of awardees
based upon whether one chooses to count a Nobel laureate who is born in a
country or where the person is located at the time of the award. For
example, there are 323 Nobel laureates (1901-2012) who were affiliated
with an organization in the USA at the time they were awarded the Nobel
prize and 247 Nobel laureates who were born in the USA.7
Second, and perhaps even more important than the sources from which data
are drawn, is the use of complete data sets and not just those that
support a hypothesis. The selective use of data from secondary sources has
no place in science to support, refute or generate hypotheses. This is a
serious methodological lapse and is called into question by the following:
1. Wikipedia lists 71 countries with per capita Nobel laureate data6, yet
only 23 were selected for Messerli's analysis; and 2. Data on chocolate
consumption used were from non-contiguous years (2002, 2004, 2010 and
2011) although data from the same sources are available for multiple
intervening years and per capita chocolate consumption for countries also
change from year to year but Messerli chose certain data while excluding
other data. Which data were selected skews the correlation substantially.
For example, if one selects the top 10 chocolate consuming countries and
using Messerli's data, the correlation is non-existent (r2= 0.04).
It is important to remember in any hypothesis generating study that bias
is easily introduced into that study through design flaws (e.g., selective
use of data or use of secondary sources) as well as known statistical
artifacts (e.g., ecological analysis2). Such bias can render the study
completely useless or, worse, damages the integrity of the scientific
process and the peer-review process of publication. As with others in the
medical and scientific community2-5 and the press, we did not see
Messerli's article as a joke intended by the author and the NEJM. However,
we assert that if an article is published in a medical journal draws
widespread publicity and is interpreted inappropriately as a valid
scientific study, it is the responsibility of the editors of that journal
to clarify the misinterpretation. Otherwise, the integrity of all
scientific journals may become suspect. This will be the subject of an
editorial in Practical Neurology.
Competing Interests: None
Contributorship statement: This article was originally conceived by BDP
and was discussed with the other two authors who helped in the analysis
and writing of the original article and its reviews. Each author
contributed to the writing and revision of this revised article and
approved the final version.
References
1. Dunstan, F. Nobel Prizes, Chocolate and Milk: The Statistical View
Pract Neurol 2013;13:206-207.
2. Messerli, F.H. Chocolate Consumption, Cognitive Function, and Nobel
Laureates N Engl J Med 2012;367:16:1562-4.
3. Maurage, P., Heeren, A., Pesenti, M. Does Chocolate Consumption Really
Boost Nobel Award Chances The Peril of Over-Interpreting Correlations in
Health Studies" J Nutr 2013;143:931-933.
4. Kayser, M. Editor's pick: Christmas is coming-time for chocolate to get
ready for your Nobel Prize Investigative Genetics 2012;3:26.
5. Linthwaite, S., Fuller, G.N., Milk, chocolate and Nobel prizes Pract
Neurol 2013;13:63.
6. List of countries by Nobel laureates per capita [Internet]. San
Francisco: Wikipedia.-[accessed 2012 October 25]. Available from:
http://en.wikipedia.org/wiki/List_of_countries_by_Nobel_laureates_per_capita
7. The Official Website of the Nobel Prize [Internet]. [accessed 2013 May
30]. Available from www.nobelprize.org.
Sir, the report on "spontaneously resolving cerebellar syndrome as a
sequelae of dengue viral infection" is very interesting [1]. In fact,
neurological complication of dengue is not common but it can be detectable
[2]. The spontaneously resolving cerebellar syndrome in this report is
questionable for the relationship to dengue. Based on the previous study
from Thailand, the spontaneously resolving pathology of cerebellum...
Sir, the report on "spontaneously resolving cerebellar syndrome as a
sequelae of dengue viral infection" is very interesting [1]. In fact,
neurological complication of dengue is not common but it can be detectable
[2]. The spontaneously resolving cerebellar syndrome in this report is
questionable for the relationship to dengue. Based on the previous study
from Thailand, the spontaneously resolving pathology of cerebellum was not
detected [3]. Although virus can be detected at cerebellum it is usually
identified in death cases [3 - 4].. The case of spontaneously resolving
cerebellar syndrome is usually identified in the patients with concurrent
infection between dengue and Epstein-Barr virus infection [5]. The
interesting topic is whether there is any interaction during co-infection
that contribute to observed cerebellar pathology.
References
1. Weeratunga PN, Caldera HP, Gooneratne IK, Gamage R, Perera WS,
Ranasinghe GV, Niraj M. Spontaneously resolving cerebellar syndrome as a
sequelae of dengue viral infection: a case series from Sri Lanka. Pract
Neurol. 2013 Jul 9. [Epub ahead of print]
2. Wiwanitkit V. Dengue fever: diagnosis and treatment. Expert Rev Anti
Infect Ther. 2010 Jul;8(7):841-5.
3. Wiwanitkit V. Magnitude and pattern of neurological pathology in fatal
dengue hemorrhagic fever: a summary of Thai cases. Neuropathology. 2005
Dec;25(4):398.
4. Ramos C, S?nchez G, Pando RH, Baquera J, Hern?ndez D, Mota J, Ramos J,
Flores A, Llaus?s E. Dengue virus in the brain of a fatal case of
hemorrhagic dengue fever. J Neurovirol. 1998 Aug;4(4):465-8.
5. Karunarathne S, Udayakumara Y, Fernando H. Epstein-Barr virus co-
infection in a patient with dengue fever presenting with post-infectious
cerebellitis: a case report. J Med Case Rep. 2012 Jan 30;6(1):43.
I really enjoyed Dr. Fuller's wonderful article on a likely emerging
public and professional fascination with neurology. The bad news, however,
is humankind's perpetual fascination with phobias; a fascination with
'death' being but one example. I'd perhaps say that neurology has joined
some rather elite company.
I would postulate that neurophobia, rather than neurophilia, drives
the impetus to produce copious ar...
I really enjoyed Dr. Fuller's wonderful article on a likely emerging
public and professional fascination with neurology. The bad news, however,
is humankind's perpetual fascination with phobias; a fascination with
'death' being but one example. I'd perhaps say that neurology has joined
some rather elite company.
I would postulate that neurophobia, rather than neurophilia, drives
the impetus to produce copious articles and books on neurology. I am still
hopeful that all the books I have purchased on neurology will miraculously
cure me of my phobia (notwithstanding the fact that reading neurology
texts convinces me that I have alexia).
Medscape's 2012 Physician Lifestyle Report by Dr. Carol Peckam has
neurologists tied for first place as the most unhappy of campers. So, no
cigar there either.
I applaud Dr. Fuller again for the propaganda piece on neurology: I
hope it works.
We enjoyed the review by our colleagues Finlayson et al 1 from the
United Kingdom, Congenital Myasthenic service, covering all aspects of the
congenital myasthenic syndromes. We would, however, suggest that the
section on neurophysiology could have been expanded and elaborated more.
To state that the neurophysiological findings in congenital myasthenic
syndromes are similar to those in autoimmune myasthenia gravis is corr...
We enjoyed the review by our colleagues Finlayson et al 1 from the
United Kingdom, Congenital Myasthenic service, covering all aspects of the
congenital myasthenic syndromes. We would, however, suggest that the
section on neurophysiology could have been expanded and elaborated more.
To state that the neurophysiological findings in congenital myasthenic
syndromes are similar to those in autoimmune myasthenia gravis is correct
perhaps with respect to repetitive nerve stimulation but when talking
about single fibre EMG (SFEMG) it should be emphasised for accuracy that
it is stimulated single fibre EMG (StimSFEMG) that should be used in
children, certainly under the age of eight years or in the intensive care
setting, and not the voluntary SFEMG technique, which requires significant
levels of patient cooperation. Furthermore, with most congenital
myasthenic syndromes (CMS) having symptoms at birth, which do not always
include ptosis, the use of StimSFEMG should be encouraged as it has
superior sensitivity in comparison to repetitive nerve stimulation, which
makes it the better screening test. The test is well tolerated and is
usually performed in the outpatient setting with the child awake. The
problem of the specificity of StimSFEMG can be addressed if the technique
is used as part of a more wide-ranging neurophysiological examination
including nerve conduction studies and EMG examination of limb and bulbar
muscles. As an example, demonstration of significant myopathic changes in
other muscles will direct the clinician more to the diagnosis of a
myopathy with associated secondary neuromuscular transmission defect
rather than a primary myasthenic syndrome.
We do not hesitate to use Stim SFEMG, which is well tolerated even by the
youngest of infants, and consequently we have seen a decrease in both the
age at referral for investigation and subsequent diagnosis over the years.
This approach has to be encouraged as in several studies it is clear that
in many children with CMS, symptoms have been present from birth, which
are often non-specific, such as feeding difficulties 2 or stridor 3. Many
of us have experienced the consequences of delayed diagnosis, regrettably
including sibling death, and we feel that the liberal use of this
excellent technique has been a major factor in preventing this by
providing an early diagnosis. In an article for a wide readership it is
perhaps an omission not to use this opportunity to advertise this
technique, available at many Neurophysiological centres (including those
of the authors). Hopefully this letter will in part address this
oversight.
Reference List
1 Finlayson S, Beeson D, Palace J. Congenital myasthenic syndromes:
an update. Pract Neurol 2013;13:80-91.
2 Kinali M, Beeson D, Pitt MC, et al. Congenital Myasthenic
Syndromes in childhood: Diagnostic and management challenges 1. J
Neuroimmunol 2008 15;201-202:6-12.
3 Jephson CG, Mills NA, Pitt MC, et al. Congenital stridor with
feeding difficulty as a presenting symptom of Dok7 congenital myasthenic
syndrome. Int J Pediatr Otorhinolaryngol 2010;74:991-994.
I read with interest the debate between Nightingale el al. and Schott about whether we should routinely test for HIV in patients presenting with cognitive impairment 1,2 . I assume that while the authors have taken rather polarized views to state their point, the correct answer lies somewhere in between. Testing for HIV shall not be the foremost in my mind in a 75-year-old male presenting with slowly progressive cognitive...
sir/madam,
Can myoclonus involve large muscles like the trunk muscles giving out just one jerk with a duration of a fraction of a second?Would it be justified to term this phenomena as a myoclonic seizure or a complex myoclonus when there is LOC for that fraction of a second;happening while falling asleep only.Or can it be a sleep disorder,a hypnic jerk?
Conflict of Interest:
...We welcome the article by Jones et al, and in particular the chance to compare the protocol used in their institution with the one we hope to implement (1).
In Northern Ireland, we are in the process of drawing up a regional protocol for the management of status epilepticus, due to wide variation in current practice. We carried out preliminary work to see where the gaps in knowledge are, so that we can create a...
We thank Dr Lilleker for his comments. We agree that use of PCP prophylaxis must provide benefit that would outweigh any attendant risk. As suggested in our article, this risk is likely to vary depending on the dose and duration of steroid therapy, the co-administration of other biologicals and the systemic health of the patient. A patient with e.g., systemic vasculitis-associated mononeuritis multiplex who has also b...
I thank the authors for highlighting this difficult topic with a very thought provoking article.
In immunosuppressing a patient with neurological disease, as with anything a physician does to a patient, there are potential risks to take into account and to be weighed up against the proposed benefits. Indeed, this sort of "cost-benefit" analysis is a central tenant of decision making in much of life outside of me...
This is a superb book that deserves to be better known, at least on my side of the Atlantic. In addition to Barker's outstanding depiction of WW1 Britain, the sympathetic and revealing exploration of the physician- patient relationship is peerless. Interested readers should know that Regeneration is the first book in a trilogy, though neither is quite as good as Regeneration. The second book, The Eye in the Door, is qui...
In a paper published last year in the New England Journal of Medicine (NEJM), Messerli noted "a surprisingly powerful correlation between chocolate intake per capita and the number of Nobel laureates in various countries," which he postulated as "most likely" related to the cognitive enhancing benefits of chocolate.1 This article in one of the premier journals in the world received extraordinary press reports around the t...
Sir, the report on "spontaneously resolving cerebellar syndrome as a sequelae of dengue viral infection" is very interesting [1]. In fact, neurological complication of dengue is not common but it can be detectable [2]. The spontaneously resolving cerebellar syndrome in this report is questionable for the relationship to dengue. Based on the previous study from Thailand, the spontaneously resolving pathology of cerebellum...
I really enjoyed Dr. Fuller's wonderful article on a likely emerging public and professional fascination with neurology. The bad news, however, is humankind's perpetual fascination with phobias; a fascination with 'death' being but one example. I'd perhaps say that neurology has joined some rather elite company.
I would postulate that neurophobia, rather than neurophilia, drives the impetus to produce copious ar...
We enjoyed the review by our colleagues Finlayson et al 1 from the United Kingdom, Congenital Myasthenic service, covering all aspects of the congenital myasthenic syndromes. We would, however, suggest that the section on neurophysiology could have been expanded and elaborated more. To state that the neurophysiological findings in congenital myasthenic syndromes are similar to those in autoimmune myasthenia gravis is corr...
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