Dysautonomia in narcolepsy: evidence by questionnaire assessment

Background and Purpose

Excessive daytime sleepiness and sudden sleep attacks are the main features of narcolepsy, but rapid-eye-movement sleep behavior disorder (RBD), hyposmia, and depression can also occur. The latter symptoms are nonmotor features in idiopathic Parkinson's disease (IPD). In the present study, IPD-proven diagnostic tools were tested to determine whether they are also applicable in the assessment of narcolepsy.

Methods

This was a case-control study comparing 15 patients with narcolepsy (PN) and 15 control subjects (CS) using the Scales for Outcomes in Parkinson's Autonomic Test (SCOPA-AUT), Parkinson's Disease Nonmotor Symptoms (PDNMS), University of Pennsylvania Smell Test, Farnsworth-Munsell 100 Hue test, Beck Depression Inventory, and the RBD screening questionnaire.

Results

Both the PN and CS exhibited mild hyposmia and no deficits in visual tests. Frequent dysautonomia in all domains except sexuality was found for the PN. The total SCOPA-AUT score was higher for the PN (18.47±10.08, mean±SD) than for the CS (4.40±3.09), as was the PDNMS score (10.53±4.78 and 1.80±2.31, respectively). RBD was present in 87% of the PN and 0% of the CS. The PN were more depressed than the CS. The differences between the PN and CS for all of these variables were statistically significant (all p<0.05).

Conclusions

The results of this study provide evidence for the presence of dysautonomia and confirm the comorbidities of depression and RBD in narcolepsy patients. The spectrum, which is comparable to the nonmotor complex in IPD, suggests wide-ranging, clinically detectable dysfunction beyond the narcoleptic core syndrome.

Posterior reversible encephalopathy syndrome and stroke after intravenous immunoglobulin treatment in Miller-Fisher syndrome/Bickerstaff brain stem encephalitis overlap syndrome

The association of a posterior reversible encephalopathy syndrome (PRES) without arterial hypertension with autoimmune-mediated inflammatory neuropathies such as Guillain-Barré syndrome (GBS) is a rare and poorly understood phenomenon. To date, PRES has been described as initial manifestation, coincidental finding, or adverse event subsequent to immunomodulatory treatment with intravenous immunoglobulin (IVIG) in cases of axonal and demyelinating GBS as well as in Miller-Fisher syndrome (MFS). We here report a case of MFS/Bickerstaff brain stem encephalitis (BBE)-overlap syndrome and nonhypertensive PRES that occurred in close temporal association with IVIG treatment and caused stroke. Immunoadsorption ameliorated the disease course. Our case supports the notion that in severe cases, immunoadsorption should be considered as first-line therapy instead of IVIG for rapid removal of IgG and thus to hasten recovery and improve functional outcome.

Short and long term outcome of bilateral pallidal stimulation in chorea-acanthocytosis

Background

Chorea-acanthocytosis (ChAc) is a neuroacanthocytosis syndrome presenting with severe movement disorders poorly responsive to drug therapy. Case reports suggest that bilateral deep brain stimulation (DBS) of the ventro-postero-lateral internal globus pallidus (GPi) may benefit these patients. To explore this issue, the present multicentre (n=12) retrospective study collected the short and long term outcome of 15 patients who underwent DBS.

Methods

Data were collected in a standardized way 2-6 months preoperatively, 1-5 months (early) and 6 months or more (late) after surgery at the last follow-up visit (mean follow-up: 29.5 months).

Results

Motor severity, assessed by the Unified Huntington’s Disease Rating Scale-Motor Score, UHDRS-MS), was significantly reduced at both early and late post-surgery time points (mean improvement 54.3% and 44.1%, respectively). Functional capacity (UHDRS-Functional Capacity Score) was also significantly improved at both post-surgery time points (mean 75.5% and 73.3%, respectively), whereas incapacity (UHDRS-Independence Score) improvement reached significance at early post-surgery only (mean 37.3%). Long term significant improvement of motor symptom severity (≥20 % from baseline) was observed in 61.5 % of the patients. Chorea and dystonia improved, whereas effects on dysarthria and swallowing were variable. Parkinsonism did not improve. Linear regression analysis showed that preoperative motor severity predicted motor improvement at both post-surgery time points. The most serious adverse event was device infection and cerebral abscess, and one patient died suddenly of unclear cause, 4 years after surgery.

Conclusion

This study shows that bilateral DBS of the GPi effectively reduces the severity of drug-resistant hyperkinetic movement disorders such as present in ChAc.

Hallucinations in neurodegenerative diseases

Patients with neurodegenerative disease frequently experience hallucinations and illusionary perceptions. As early symptoms, hallucinations may even have diagnostic relevance (i.e., for the diagnosis of Lewy Body Dementia). In the later course of the disease, hallucinations may appear as characteristic symptoms and often constitute a particular challenge for therapeutic endeavors. Here, the distinction of disease-inherent hallucinations from medication-associated perceptual disturbances is particularly relevant. Synucleinopathies and tauopathies have different risk profiles for hallucinations. In synucleinopathies hallucinations are much more frequent and phenomenology is characterized by visual, short-lived hallucinations, with insight preserved for a long time. A “double hit” theory proposes that dysfunctionality of both associative visual areas and changes of limbic areas or the ventral striatum are required. In contrast, in tauopathies the hallucinations are more rare and mostly embedded in confusional states with agitation and with poorly defined or rapidly changing paranoia. The occurrence of hallucinations has even been proposed as an exclusion criterion for tauopathies with Parkinsonian features such as progressive supranuclear palsy. To date, treatment remains largely empirical, except the use of clozapine and cholinesterase inhibitors in synucleinopathies, which is evidence-based. The risk of increased neuroleptic sensitivity further restricts the treatment options in patients with Lewy Body Dementia. Coping Strategies and improvement of visual acuity and sleep quality may be useful therapeutic complements.

[Pathogenesis of narcolepsy: from HLA association to hypocretin deficiency]

Narcolepsy is a rare and chronic sleep disorder, characterised by excessive daytime sleepiness. Frequently associated signs are cataplexy, sleep paralysis and hypnagogic or hypnopompic hallucinations. Advances in understanding the pathogenesis of the disease have essentially been elucidated during the last fifteen years. The most significant finding has been the discovery of hypocretin-1 and -2 in 1998. Hypocretin-containing cells have widespread projections throughout the entire CNS and play a crucial role in the regulation of the sleep-wake cycle. They also contribute to olefaction and to the regulation of food intake. Animal models and human studies concordantly show that the disturbed hypocretin system is the probable cause of narcolepsy. However, it remains unclear why there is neuronal death of hypocretin-producing cells in the lateral hypothalamus. As the HLA-allele DQB1*0602 is associated with narcolepsy and hypocretin deficiency, an autoimmune reaction against hypocretin-producing neurons has been vigorously discussed. Newly discovered gene polymorphisms as well as previously unknown pathogenetic mechanisms, linking the sleep-wake cycle with the immune system, may also contribute to the pathogenetic cascade. Worthy of mention in this context is, e.g., the "insulin-like growth factor"-binding protein 3 (IGFBP3), whose overexpression causes a down-regulation of the hypocretin production. Substitution of the deficient neuropeptides by hypocretin agonists may become the causal treatment strategy of the future, if an adequate administration route can be found. Presently, animal trials, including genetic therapy, cell transplantations or the administration of hypocretin receptor agonists, are underway.

Prognostic value of electroencephalography and evoked potentials in the early course of malignant middle cerebral artery infarction

Space-occupying brain edema may lead to a malignant course in patients with large middle cerebral artery infarction. Decompressive hemicraniectomy has to be initiated early to prevent further tissue damage. In this retrospective study, we analyzed electroencephalography (EEG) and evoked potentials (EPs), obtained within 24 h after onset of stroke, in 22 patients suffering from a large middle cerebral artery infarction. Our findings indicate a prognostic value of EEG and brainstem auditory EP (BAEP): the absence of delta activity and the presence of theta and fast beta frequencies within EEG-focus predicted a non-malignant course. In contrast, diffuse generalized slowing and slow delta activity in the ischemic hemisphere pointed to a malignant course. Likewise, pathological BAEP were correlated with a malignant course. The coexistence of background slowing and pathological BAEP showed the highest level of significance. In conclusion, our findings implicate an additional early application of electrophysiological methods in stroke patients. EEG and EP deliver useful information to select those patients who develop malignant edema.

[Anti-NMDA receptor encephalitis: a neurological and psychiatric emergency]

Anti-NMDA receptor encephalitis is a severe autoimmune disease, first described in 2007.  Since then a number of cases have been published, suggesting that to date the disease is a considerably underdiagnosed entity. The clinical picture develops over a relatively long period of time and is initially characterised by psychiatric symptoms such as decreased levels of consciousness and hallucinations as well as paranoid behaviour. In the course of the disease neurological symptoms occur, in particular, seizures, autonomic dysfunction and dyskinesias. Due to the young age of many patients, the symptoms are often mistaken as to result from drug-induced psychosis. Anti-NMDA receptor Encephalitis was first described in young women with teratomas. In the past few years the disorder has also been reported in men and children and without any detectable neoplasia. The diagnosis is based on the characteristic clinical picture and supportive findings in MRI, EEG and the cerebrospinal fluid. Hereby, highly specific autoantibodies directed against the NR1 subunit of the NMDA-type glutamate receptors in the CSF (or serum) play an important role and should be sought specifically in any case of an "encephalitis of unknown cause". The prognosis of the disease is favourable, even when autonomic disorders entail ventilation and/or prolonged intensive care treatment is necessary. Nonetheless, the clinical outcome is highly dependent on an early diagnosis and immunotherapy without delay. In the case of a malignancy, tumour removal is also crucial. Taken together, an interdisciplinary approach including neurologists, psychiatrists, oncologists and gynaecologists is essential in order to detect and effectively treat this disorder.

Immunoadsorption in patients with chronic inflammatory demyelinating polyradiculoneuropathy with unsatisfactory response to first-line treatment

BACKGROUND/AIMS

First-line treatment options for chronic inflammatory demyelinating polyradiculoneuropathy (CIDP) are corticosteroids, intravenous immunoglobulin, and plasma exchange. In a significant number of patients, first-line therapy fails, and long-term maintenance treatment still remains a therapeutic challenge. Immunoadsorption (IA) may be an alternative to classical plasma exchange in the therapy of immune-mediated neurologic diseases. The aim of this investigation was to evaluate efficacy and safety of IA in patients with CIDP with unsatisfactory response to first-line treatment options.

METHODS

CIDP patients received adjunct IA treatment using tryptophan-immune adsorbers. The inflammatory neuropathy cause and treatment disability (INCAT) score was used to grade disability and monitor treatment effects.

RESULTS

In total, 14 CIDP patients were analyzed. Ten patients were treated in hospital. After one IA treatment series, the INCAT score decreased significantly in all 10 patients. Four of these 14 patients were treated in outpatient clinics using long-term maintenance IA with 1-2 treatments per week. In these 4 patients, effects of long-term maintenance IA resulted in an improvement of overall disability. In all patients, IA was safe, well tolerated, and no severe adverse effects occurred.

CONCLUSION

IA could be an effective and safe option for CIDP patients with unsatisfactory response to first-line treatment options and for long-term maintenance treatment.

[Diagnostic work-up in Whipple's disease with cerebral involvement]

The diagnostic work-up in the case of a suspected cerebral involvement of Whipple's disease involves neuroimaging and analysis of cerebrospinal fluid (CSF) including polymerase chain reaction (PCR) assays for Tropheryma whipplei. As neurological findings may be complex and unspecific, extracerebral symptoms often lead to the suspicion of Whipple's disease. We report the cases of two patients in whom the suspected diagnosis of Whipple's disease could not be proved either by endoscopy or by the analysis of CSF. Only by means of a cerebral biopsy was the diagnosis assumed and specific therapy was initiated.

[Acute headache: limitations of cerebral computed tomography and analysis of cerebrospinal fluid in the diagnosis of subarachnoid haemorrhage]

Subarachnoid haemorrhage constitutes a neurological emergency. In most cases the diagnosis is easy to establish by cerebral computed tomography or cerebrospinal fluid tap. However, in rare cases verification of the diagnosis is more difficult and a residual uncertainty remains. We describe three patients supposed to have a subarachnoid haemorrhage without pathological findings in both cerebral computed tomography and cerebrospinal fluid. In these cases vasospasm or cerebral aneurysm were detected by means of transcranial Doppler sonography and/or conventional angiography. We comment on the special features of this rare presentation of a severe acute neurological emergency, and we discuss diagnostic work-up and differential diagnoses.

[Thrombolytic therapy in conversion disorder with sensorimotor hemisyndrome]

We here report on a 43-year-old man who was repeatedly admitted to our stroke unit with acute onset of sensorimotor hemisyndrome of acute onset. In most cases symptoms ceased shortly after admission, but twice when symptoms persisted thrombolytic therapy was applied. This case demonstrates that in emergency situations a rare differential diagnosis like conversion disorder with sensorimotor deficits may be hard to establish even if the patient presents to the same emergency unit.

[Mistaking a long QT syndrome for epilepsy: does every seizure call for an ECG?]

Syncope is a common and difficult differential diagnosis for epilepsy. One possible cause for a cardiac syncope is a long QT syndrome (LQTS). LQTS with torsade de pointes tachycardia can lead to lethal ventricular fibrillation and cardiac arrest. Patients with LQTS when first diagnosed as suffering from epileptic fits often experience a particularly long diagnostic delay which may even take years. In some cases, the diagnosis of LQTS is not made until the patient needs resuscitation due to a cardiac arrest. Therefore, ECG recording should be performed for every patient presenting with a seizure considered to be of epileptic origin not only at the beginning of the disease but also when fits occur in spite of antiepileptic treatment in order to prevent an incorrect diagnosis and delay in making the correct diagnosis.

[Detection of aneurysm by 3 Tesla MRA in third cranial nerve palsy]

The diagnostic work-up of patients with third cranial nerve palsy includes neuroimaging because the lesion of the oculomotor nerve may result from compression due to an aneurysm. The advantages and disadvantages of different neuroimaging techniques, i. e. magnetic resonance angiography (MRA), computed tomography angiography (CTA) and intra-arterial digital subtraction angiography (DSA), are still under debate. In this context, the present case report demonstrates that the application of 3 Tesla-MRA may help to detect an aneurysm of the internal carotid artery which had remained undetected by non-invasive standard methods applied before. Therefore 3 Tesla-MRA may help to fill a gap in diagnostic approaches between non-invasive (MRA, CTA) and invasive (DSA) neuroimaging techniques.

Patient-tailored, imaging-guided, long-term temozolomide chemotherapy in patients with glioblastoma

We present two patients with glioblastoma with an unusually stable clinical course and long-term survival who were treated after surgery and radiotherapy with adjuvant temozolomide (TMZ) chemotherapy for 17 and 20 cycles, respectively. Afterward, adjuvant TMZ chemotherapy was discontinued in one patient and the dosage of TMZ was reduced in the other. In addition to clinical status and magnetic resonance imaging, the biologic activity of the tumors was monitored by repeated methyl-11C-l-methionine (MET) and 3'-deoxy-3'-18F-fluorothymidine (FLT) positron emission tomography (PET) studies in these patients. In these patients, repeated MET- and FLT-PET imaging documented complete response to the initial treatment regimen, including resection, radiation, and TMZ, and during the course of the disease, recurrent, uncontrollable tumor activity. Continuation or dose escalation of TMZ in both patients was shown to be ineffective to overcome the metabolic activity of the tumor. Our data suggest that repeated MET- and FLT-PET imaging provide information on the biologic activity of a tumor that is highly useful to monitor and detect changes in activity.

[Cerebrotendinous xanthomatosis]

HISTORY AND CLINICAL FINDINGS

A 43-year-old woman had since childhood suffered from progressive dementia. Gait ataxia and mild polyneuropathy were noted in the neurological examination. She also had painful xanthomas of the achilles tendons. A bilateral cataract operation had been performed during adolescence.

INVESTIGATIONS

An elevated concentration of cholestanol and a normal cholesterol level were found in the blood samples. The cerebral computed tomography revealed slight cerebral atrophy, predominantly affecting the cerebellum. Neurophysiological tests detected a sensory polyneuropathy in the legs. In addition the electroencephalogram showed a generalized slowing of electrical activity.

DIAGNOSIS, TREATMENT AND COURSE

Clinical findings and laboratory values indicated the diagnosis of a cerebrotendinous xanthomatosis. After initiation of a drug therapy, based on a combination of an HMG-CoA-reductase inhibitor (simvastatin 20 mg/day) and a bile acid, chenodeoxycholic acid (15 mg/kg/day), further progression of the disease was prevented.

CONCLUSION

The diagnosis of cerebrotendinous xanthomatosis is easily made in patients presenting all clinical symptoms expected in the disease. However, up to 30% of the patients do not show severe xanthomas. Especially in early stages of the disease the diagnosis may be difficult. Treatment can be efficacious and should be started as early as possible to prevent irreversible damage, particularly in the nervous system.