Giant cell arteritis (GCA) is a nasty inflammatory disorder that affects the large arteries. Because it characteristically involves the temporal artery, this form of vasculitis is also referred to as temporal arteritis. It usually affects people over the age of 50 years and manifests with sudden onset headache, scalp pain, and a thick, tender temporal artery. GCA is often accompanied by polymyalgia rheumatica (PMR) , a painful condition of the joints and muscles. The active systemic inflammation in GCA is often detected by the erythrocyte sedimentation rate (ESR) or C-reactive protein (CRP) tests. These distinguishing features constitute most of the diagnostic criteria for GCA.
Most people with GCA however do not have all the ‘classical’ features of the disease. A high index of suspicion is therefore required to sniff out the duplicitous miscreant. It is particularly imperative to make the diagnosis as early as possible to prevent the dreaded complications of GCA, sudden blindness and stroke. The treatment of GCA, implemented according to established treatment guidelines, involves several months of oral steroids, drugs which cause immune suppression and a host of other side effects. It is therefore essential that the diagnosis of GCA is made correctly to avoid putting the patient on a long, risky, and unnecessary treatment.
What then is the value of the temporal artery biopsy in the diagnosis of GCA? This is the question posed by Bowling et al in their incisive paper titled Temporal artery biopsy in the diagnosis of giant cell arteritis: does the end justify the means?They reviewed 129 temporal artery biopsies and found that the clinical diagnosis of GCA was confirmed in only 13% of cases. Furthermore, the outcome of the biopsy rarely ever influenced the treatment; 87% of those with a normal biopsy result still continued their treatment. The miffed authors therefore rhetorically, and indignantly, asked: “can we justify invasive surgery to all patients on histological grounds when the results may not alter management?”
This is an entirely reasonable question especially because there are other more accurate and less invasive ways of establishing the diagnosis of GCA. These include:
But the answer to the authors’ rhetorical question is anyones guess. It is a sad tradition of medicine that studies such as these take ages to change practice. Indeed I predict the the temporal artery biopsy will sidestep this minor hurdle and simply continue its long and agonising reign. Despair!
Statins are famous, and their fame lies in their ability to bust cholesterol, the villain in many medical disorders such as heart attack (myocardial infarction) and stroke. Some may add that statins are infamous, and this is partly because of their side effects such as muscle pain. Love them or hate them, we can’t get away from statins…even as the debate rages about their benefits and downsides.
It is not surprising therefore that the statin debate will filter into neurology. The sticking point here however has nothing to do with cholesterol busting, but all to do with whether statins increase or reduce the risk of developing Parkinson’s disease (PD). Strange as it may seem, statins and PD have a long history. And a positive one generally, I hasten to add. There is a large body of evidence to suggest a protective effect of statins on PD as reflected in the following studies:
The authors of this paper set out to investigate ‘the controversy surrounding the role of statins in Parkinson’s disease’. In this retrospective analysis of over 2,000 people with PD, and a similar number of control subjects, theauthors found that statins significantly increased the risk of developing PD. This is clearly a conclusion looking for a fight!
I must admit I was totally unaware there was any controversy about statins and PD. I was therefore curious to find out what studies are out there fuelling it. Which other trials have bucked the trend and reported an increased risk of PD from statins? And where best to find the answers but in PubMed, the repository of all human knowledge! And I found that there were only a few studies that did not report a protective effect of statins on PD, and these studies concluded, quite reasonably, that they found no relationship between PD and statins. Here are a few of the studies:
These papers reporting the absence of evidence seem happy to engage in an amicable debate to resolve the question.
One study however stood out like a sore thumb because it positively reported a negative effect of statins on PD (try and work that out!). This 2015 study, also published in Movement Disorders, is titled Statins,plasmacholesterol, and risk of Parkinson’s disease: a prospective study. The paper concludes that “statin use may be associated with a higher PD risk, whereas higher total cholesterol may be associated with lower risk“. Not only are the authors arguing that statins are bad for PD, they are also suggesting that cholesterol is good! This is a paper that was itching for fisticuffs.
What is a jobbing neurologist to do? What are the millions of people on statins to do? Whilst awaiting further studies, I will say stay put. Go with the bulk of the evidence! And keep track of TheSimvastatin Trial, funded by TheCure Parkinson’s Trust. This trial is looking at the benefit of statins in slowing down PD. And surely, very soon, the science will lead to a resolution of the argument-all you need to do is keep track of everything PD in Neurochecklists.
Prophetic it seems, as I am here forced to revisit the topic because I came across a few recent interesting reports on the neurology of gluten.
Take this case report from Nutrients titled gluten psychosis: confirmation of a new clinical entity. The article comes with some good references that suggest it will do no harm to check anti-gliadin antibodies in people with unexplained psychosis. I do wonder how one case report would confirm an entity such as gluten psychosis, but there you are.
Gluten-induced visual impairment
The second item is another case report published in Journal of Neurology titled severe, persistent visual impairment associated with occipital calcification and coeliac disease. The subject of the case report has long-standing coeliac disease and visual impairment. Her brain MRI scan showed calcifications in the visual area, evidence the authors claim, of celiac disease causing brain calcifications …..and thereby causing the patients visual loss. Is it just a case of correlation rather than causation? But there you are.
This is a quick post to highlight changes and proposed changes to some neurological terms. It is not unusual for such changes to occur every now and then. We have, for example, seen benign intracranial hypertension (BIH) changed to idiopathic intracranial hypertension (IIH), and Hallavorden Spatz disease transformed into pantethonate kinase associated neurodegeneration (PKAN).
There are many sources of neurology information, as I listed in my previous post titled what are the most reliable neurology reference sources? These sources let us know what is in and what is out; what is breaking and what has gone stale. Keeping on top of the ever-shifting information the journals churn out is challenging, but interesting. This information is the life blood of The Neurology Lounge, and keeps neurochecklistscurrent and reliable.
In the task of keeping level with neurological developments, I first go to the journal Neurology, one of the clear leaders of the pack. Check it out on twitter under its handle, @GreenJournal. Browsing through a recent issue, I was struck by a paper titled Population-based risks for cancer in patients with ALS. The authors of this paper report that people with motor neurone disease (MND) appear to be protected from developing many cancers, including the notorious lung cancer. In contrast, they are at a higher risk of testicular and salivary gland cancer.
So, is the latest study bucking the trend? Does MND really protect against some cancers and predispose to others? What does this all mean for people with MND? Or is all this just a quirk of the statistics? Questions, questions. I suspect this paper has just re-opened a can of worms, and more studies will surely follow. And they will refute and confirm the findings in equal measure.
For now, MND remains an enigma. You may explore it a bit more in my previous blog posts on the subject…and leave your thoughts behind in the comments box.
Lyme disease is a well-known infection. It takes its name from Lyme, Connecticut, where it was first recognised as a distinct disease in 1975. The disease is caused by the infamous Borrelia species which get into humans through tick bites. The transmission typically occurs when the victim is taking a gingerly walk in deer-inhabited forests, usually in the pleasant months of May or June. The tick may leave a signature skin rash, erythema migrans. In the ideal situation, the clear history and a positive Lyme serology test make the diagnosis. A short treatment course with an antibiotic such as doxycycline or ceftriaxone and, hey presto, Lyme disease is cured, totally and permanently. And doctor and patient live happily ever after….
The above scenario, unfortunately, only plays out on planet Utopia. On planet earth, things are rarely that straightforward. In reality, the story is often vague and devoid of ticks, deer, and forests. The Lyme blood test is often ambiguous and frequently misleading. And in many cases, the antibiotic only partially improves the symptoms. The end result is a frustrated patient and a baffled doctor. Several Google searches after and the patient is convinced they have chronic Lyme disease, and demanding extended courses of antibiotic treatment. Several PubMed searches later, the doctor finds no scientific evidence to support prolonged antibiotic use, and refuses to acquiesce (apologies to Captain Barbossa). A vicious pantomime then follows.
Neurologists tango with Lyme disease in the form of neuroborelliosis. This form of Lyme disease is a nightmare for neurologists because of the varied ways it may present. This was highlighted by a recent excellent review in the American Journal of Neuroradiology titled Lyme Neuroborreliosis: Manifestations of a Rapidly Emerging Zoonosis. These manifestations include a painful lymphocytic meningoradiculitis, cranial nerve palsies, meningoencephalitis, encephalomyelitis, and transverse myelitis. Then there is the nebulous concept of chronic Lyme neuroborreliosis, something the authors say is ‘a focus of ongoing conjecture and controversy‘. They, however, jumped into this minefield and proposed a set of diagnostic criteria which include characteristic symptoms, specific serum antibodies, spinal fluid inflammation, and spinal fluid antibody production. On Utopia, you might add.
Uncertainty and doubt abound in Neurology. There are many evidence-free areas where experts rub each other the wrong way. These controversies are big and occur in all neurology subspecialties. Controversy-busters have tried for about a decade to iron out these wrinkles on neurology’s face, but the unanswered questions remain. This is why there is a 10th World Congress of Controversies in Neurology (CONy) holding in Lisbon this year.
I want to assure you I have no conflict of interest to declare in this blog. My interest is to explore which questions have plagued this conference over the last 10 years to pick out the most controversial topics in neurology. To do this I reviewed all previous conference programs and focused on the items that were slated for debate. I looked for practical topics that have remained unresolved, or are just emerging. Here are my top controversial neurological questions:
Which should be the first-line therapy for CIDP? Steroids vs. IVIg
Should disease-modifying treatment be changed if only imaging findings worsen in multiple sclerosis?
Should disease-modifying therapies be stopped when secondary progressive MS develops?
Should non-convulsive status epilepsy be treated aggressively?
Does traumatic chronic encephalopathy (CTE) exist?
Does corticobasal degeneration (CBD) exist as a clinico-pathological entity?
Is ß-amyloid still a relevant target in AD therapy?
Will electrical stimulation replace medications for the treatment of cluster headache?
Carotid dissection: Should anticoagulants be used?
Is the ABCD2 grading useful for clinical management of TIA patients?
Do COMT inhibitors have a future in treatment of Parkinson’s disease?
Going through this list, I feel reassured that the experts differ in their answers to these questions? The acknowledgement of uncertainty allows us novices to avoid searching for non-existent black and white answers. It is however also unsettling that I thought some of these questions had been settled long ago. It goes to show that apparently established assumptions are not unshakable?
Do you have the definitive answers to resolve these controversies? Are there important controversies that are missing here? Please leave a comment