José M. Polo

Neuroimaging diagnosis of Tolosa-Hunt syndrome : MRI contribution

Objective.—To present our experience in the neuroradiological diagnosis of six patients with Tolosa‐Hunt syndrome.

LRRK2 G2019S is a common mutation in Spanish patients with late-onset Parkinson's disease

Mutations in the leucine-rich repat kinase 2 (LRRK2) gene have been shown to cause both autosomal dominant and sporadic Parkinsons disease (PD). The common G2019S mutation shows wide geographical distribution while R1441G has been only reported in Northern Spain. The overall frequency of these mutations remains to be established. To determine the prevalence of G2019S and R1441G mutations in our population of Cantabria (Northern Spain), we recruited 105 consecutive PD patients and 310 controls and conducted genetic analysis of these mutations. G2019S was detected in eight late-onset patients (7.6%). Five of them had no relevant family history. R1441G was not detected in any of our study subjects. The prevalence of G2019S mutation in unselected late-onset PD patients might be higher than previously reported: 3/16 (18.7%) of familial PD and 5/82 (6.1%) of sporadic PD.

Intravenous Lidocaine for Status Epilepticus

Summary: Intravenous lidocaine successfully controlled convulsive status epilepticus in eight patients. Lidocaine was administered, as a diazepam substitute, to elderly patients with chronic obstructive lung disease and to those patients unresponsive to the stated doses of intravenous diazepam. Although transient disappearance of seizures was noted after an initial dose of 100 mg, infusion of 200 mg was necessary to effectively control status. Continuous lidocaine infusion (3.5 mg/kg/h) was used in one case with good results. Undesirable side effects were not seen. The basic mechanisms for possible anticonvulsant action are reviewed. Lidocaine seems to be an effective and safe drug in convulsive status epilepticus. We suggest that lidocaine may be used as a first‐line drug, as a diazepam substitute, in the treatment of convulsive status epilepticus in patients in whom respiratory depression is undesirable and in those who do not respond to intravenous diazepam.

Spinocerebellar ataxia type 2 with Levodopa-responsive parkinsonism culminating in motor neuron disease.

We describe an exceptional spinocerebellar ataxia type 2 (SCA2) phenotype combining cerebellar ataxia, levodopa‐responsive parkinsonism, and motor neuron symptoms. We conclude that motor neuron symptoms and signs may be a striking manifestation in SCA2, masking pre‐existing cerebellar and extrapyramidal semeiology.

Tolosa-Hunt syndrome: focus on MRI diagnosis.

Experience with modern neuroimaging techniques, computed tomography (CT) and magnetic resonance imaging (MRI) scans, in the diagnosis of Tolosa-Hunt syndrome (THS) is reviewed. Conventional CT scan remains normal in about two-thirds of these patients. In the reported 22 patients meeting the IHS criteria for a THS diagnosis on whom an MRI study was performed, MRI revealed a convex enlargement of the symptomatic cavernous sinus by an abnormal tissue isointense with gray matter on short TR/TE images and isohypointense on long TR/TE images. This abnormal tissue markedly increases in signal intensity after contrast injection. MRI seems also to be the ideal technique to follow progressive resolution of the abnormal tissue after steroids. Therefore, normal MRI would probably exclude THS, whereas in the appropriate clinical setting of steroid-responsive painful ophthalmoplegia, MRI showing the cavernous sinus abnormality described here suggests a diagnosis of THS. From these data, we propose that the fourth IHS criterion for THS diagnosis, “Exclusion of other causative lesions by neuroimaging and (not compulsory) carotid angiogram” should be changed to “Finding by MRI of specific cavernous sinus abnormalities (with the characteristics described herein) which slowly resolve with steroid treatment”.

Progressive multifocal leukoencephalopathy and idiopathic CD4 lymphocytopenia

Idiopathic CD4 lymphocytopenia (ICL) is a syndrome described in patients with low counts of CD4 cells and no other causes for immunosuppression. A few cases of progressive multifocal leukoencephalopathy (PML) have been described in association with this entity. There is no effective treatment for any of them, and the clinical course and outcome are unpredictable. We report on a case of ICL with PML and review the literature, trying to identify the clinical features and the prognosis clues associated to these entities together. A 72-year-old man presented with acute onset gait instability that progressed to a severe cerebellar syndrome with cognitive decline. A cranial MRI showed findings consistent with PML, this diagnosis being confirmed by CSF analyses. Absolute number of CD4+ was 242 cells/μL. An extensive work-up including HIV tests was negative. Ten cases of PML and ICL have previously been reported. Factors contributing to the different outcomes are unknown. Although an effective treatment does not exist for PML, it has been recently demonstrated in vitro that several 5HT2A-receptor antagonists block the JC virus infection. Our patient greatly improved and remains stable 34 months after onset; we describe the potential role of mirtazapine in the treatment of PML.

Continuous Facial Myokymia in Multiple Sclerosis: Treatment with Botulinum Toxin

Continuous facial myokymia (CFM) is an involuntary undulating, vermicular movement that spreads across facial muscles and is associated with a characteristic electromyographic pattern. It is an infrequent clinical sign that almost always occurs in intrinsic brainstem lesions, particularly in multiple sclerosis (MS). It is usually present for only a few weeks, but it may persist for long periods of time being very troublesome for patients. We report 2 cases with MS and continuous hemifacial myokymia persisting for up to 1 month which disappeared after injection of botulinum toxin. Botulinum toxin A (BTX-A) has been used successfully to treat a variety of focal dystonias and occasionally in orbicularis myokymia, but its use has not been reported in continuous hemifacial myokymia. BTX-A appears to be effective and safe for treating persistent facial myokymia in MS patients.

High frequency and reduced penetrance of LRRK2 G2019S mutation among Parkinson's disease patients in Cantabria (Spain).

The frequency and penetrance of the LRRK2 G2019S mutation varies considerably in different Parkinson disease (PD) populations. This information is essential both for clinical purposes and genetic counseling. The objective of this study was to estimate the prevalence and penetrance of the G2019S mutation of the LRRK2 gene in a small region in northern Spain (Cantabria). The G2019S mutation was tested in 367 consecutive patients with PD attended as outpatients in a tertiary Hospital in Northern Spain, and 126 at‐risk family members of probands were also investigated for G2019S mutation and disease status. The gene penetrance was estimated in terms of cumulative age‐specific incidence of PD by the Kaplan‐Meier method. Thirty‐two PD patients (8.7%) carried the G2019S mutation. Penetrance estimation of the G2019S mutation was 2% at 50 years, 12% at 60 years, 26% at 70 years, and 47% at 80 years. The frequency of the G2019S mutation of the LRRK2 gene in PD patients from Cantabria is among the highest reported so far after North African Arabs and Ashkenazi Jews. At the age of 80 years only one‐half of G2019S mutation carriers manifest motor symptoms of PD.

Friedreich ataxia with minimal GAA expansion presenting as adult-onset spastic ataxia

Around a quarter of Friedreich ataxia (FA) patients, despite being homozygous for GAA expansion within the FRDA gene, show atypical presentations. Our aim is to describe the case of three brothers with long-term follow-up suffering from late onset FA manifested with spastic ataxia. The three patients belong to a family with occipital dysplasia (OD) and Chiari I malformation previously reported by us. We have carried out serial examinations since 1977. Electrophysiological and neuroimaging studies, and molecular genetic analyses of hereditary ataxias are available in all three patients. Onset of symptoms occurred between 25 and 35 years. The clinical picture consisted of progressive spastic gait, truncal and limb ataxia, dysarthria, nystagmus, hyperreflexia with knee and ankle clonus and extensor plantar response, and mild hypopallesthesia. Ages at present vary between 50 and 59. One patient is wheelchair-bound but the other two are able to walk with support. Leaving OD aside, skeletal anomalies are not prominent. All three patients showed cardiomyopathy. MR imaging revealed atrophy of the cerebellum and spinal cord. Motor and sensory nerve conduction velocities were normal. Central conduction time of both motor and sensory pathways was delayed or unobtainable. All three patients were homozygous for the GAA expansion, the smaller expanded allele ranging between 131 and 156 repeats. Four heterozygotic carriers were detected among non-ataxic relatives including one with OD; furthermore, an asymptomatic OD patient showed normal genotype. We conclude that adult onset spastic ataxia is a distinctive FA phenotype associated with minimal GAA expansion. This phenotype represents a new cause of selective distal degeneration of central sensory axons. The present concurrence of OD and FA reflects coincidental cosegregation of two different inherited disorders.

Very late‐onset Friedreich's ataxia with minimal GAA1 expansion mimicking multiple system atrophy of cerebellar type

Very late‐onset Friedreichs ataxia (VLOFA) is characterized by symptomatic onset after 40 years of age and, usually, a benign phenotype. We describe a sporadic case with onset at 53 years of age and a novel VLOFA phenotype mimicking multiple system atrophy (MSA) of cerebellar type associated with minimal GAA1 expansion. We detected several atypical features for a diagnosis of MSA, which should alert to the possibility of an inherited ataxia.