Cognitive impairment before changes appear on [18F]-fluoro-D-glucose positron emission tomography images in a patient with possible early-stage cerebellar-predominant multiple system atrophy.

Multiple system atrophy (MSA) is a sporadic, rapidly progressive neurodegenerative disorder characterized by autonomic dysfunction combined with parkinsonism or cerebellar ataxia. Patients with MSA typically suffer from cognitive disorders and rapid eye movement sleep behaviour disorder. 18 F-fluorodeoxyglucose-positron emission tomography is used to assess MSA. However, the relationship between the clinical features and findings on 18 F-fluorodeoxyglucose-positron emission tomography in patients with MSA has not yet been investigated. Here we report a case of possible early-stage cerebellar-type MSA. We concluded that cerebellar-type MSA or other factors, such as rapid eye movement sleep behaviour disorder or obstructive sleep apnoea cognitive impairment, could appear before changes are visible on 18 F-fluorodeoxyglucose-positron emission tomography images. Additionally, we concluded that the cognitive impairment could derive from cerebellar-type MSA itself, not from other factors such as rapid eye movement sleep behaviour disorder or sleep apnoea syndrome.

[Joubert syndrome diagnosed based on sleep-disordered breathing in a 25-year-old man--case report].

A 25-year-old man was referred to our hospital because of repetitive cessation of breathing during sleep. He had a history of longstanding ataxia, motor delay, and mental retardation and had been diagnosed with cerebral palsy. Neurological examination revealed ataxia, general hypotonia and wide-based, shuffling gait. Magnetic resonance imaging showed vermian aplasia and dilated fourth ventricle, consistent with Joubert syndrome. Polysomnography revealed repetitive tachypnea followed by central apnea. Tachypneic episodes were elicited by brief arousals. Nasal continuous positive airway pressure eliminated neither tachypnea nor apnea. This case indicates that a patient with Joubert syndrome may survive into adulthood and present as a case of sleep-disordered breathing.

[A 62-year-old woman with early-onset Parkinson's disease associated with the PINKi gene deletion].

We report the first case of early-onset Parkinson's disease (EOP) with the PTEN-induced kinase 1 (PINK1) gene deletion in 62 years old Japanese female. The symptoms were started with unstable gait at the age 38. Parkinsonian symptoms became apparent in 45 years old. L-Dopa was markedly effective on her parkinsonian symptoms. However, equinovarus foot induced by L-Dopa intake appeared three months prior to the admission. On admission, she presented with mild cognitive impairment, severe depression, marked retropulsion, resting tremor in the left upper limb and mild hyperreflexia in the four limbs. Rigidity was not present. Mutational analysis revealed homozygous deletion from exon 6 to 8 in the PINK1 gene. An ethnic diversity in PINK1 mutation is suggested.

[A case of myasthenia gravis with anti-MuSK antibodies showing a dramatic improvement with plasma exchange].

A 49-year-old woman with seronegative myasthenia gravis (SNMG) was admitted to our hospital with severe respiratory failure, proximal muscle weakness and bulbar palsy. Permanent tracheostomy and continuous mechanical ventilation were performed. At a previous hospital, she was diagnosed as SNMG on the basis of the positive waning during 3 Hz repetitive stimulation of the ulnar nerve, although no acetylcholine receptor antibodies (Ab) were detected by serological examination. Before admission to our hospital, she was treated with corticosteroids, intravenous immunoglobulin and tryptophan column immuno-adsorption therapy without clinical improvement. At our hospital, serological examination detected muscle-specific receptor tyrosine kinase (MuSK) Ab and plasma exchange was performed as treatment. Plasma exchange and subsequent immunomodulating therapy with corticosteroids and tacrolimus showed a dramatic clinical improvement with a marked decline of MuSK Ab level in the serum. These results suggested that plasma exchange should be considered as first choice to treat patients with refractory MuSK Ab-positive MG.

[Internal ophthalmoplegia in acute oropharyngeal palsy with anti-GQ1b and anti-GT1a IgG antibodies].

A patient with acute oropharyngeal palsy associated with internal ophthalmoplegia was reported. A 13-year-old boy had fever and diarrhea for two days. Ten days after resolution of these symptoms, he noticed difficulty in speaking (day 1). Neurological findings on day 4 included bilateral mydriasis, right abducens nerve palsy, nasal voice with absent pharyngeal reflex. Although superficial sensation was preserved, vibratory sensation was reduced in distal limbs. Tendon reflexes were generally absent. Neither ataxia nor dysautonomia was seen. Serum anti-glycolipid antibody assay on day 4 disclosed elevated IgG antibodies to GQ1b and GT1a. His cerebrospinal fluid on day 21 contained 6 mononuclear cells/microl with 137 mg/dl of total protein. Nerve conduction study on day 5 showed minimal sensory nerve involvement. Quantitative sudomotor axon reflex test was normal in the lower extremities. Low dose pilocarpine eyedrops dilated his pupils. Although mild cerebellar-like ataxia appeared on day 5, intravenous immunoglobulin (0.4 g/kg/day for four days) rapidly improved his neurological abnormalities. IgG anti-GQ1b antibody might contribute not only oropharyngeal weakness but also internal ophthalmoplegia in this patient.

[Syndrome of inappropriate secretion of antidiuretic hormone (SIADH) associated with relapsing multiple sclerosis].

We report a 47-year-old man with multiple sclerosis (MS) with previous history of recurrent sensorimotor disturbance and visual deficit. The patient developed bilateral motor weakness in the upper limbs, and systemic malaise. An administration of 20 mg/day of prednisolone was ineffective for his symptoms and he complained dyspnea a week later. On admission, his clinical findings included brainstem dysfunction with optic nerve atrophy, motor disturbance in the bilateral upper limbs, hyperreflexia, and superficial sensory disturbance. Biochemical examination revealed marked reduction in serum Na (117 mEq/l) and C1 (85 mEq/l) with increased urinary Na excretion. Although his plasma osmotic pressure decreased to 233 mOsm/kg, urinary osmotic pressure increased to 409 mOsm/kg. Serum antidiuretic hormone (ADH) concentration was 26.1 pg/ml and plasma renin activity was 0.1 ng/ml/ hour. Renal function and adrenal function were normal. Cerebrospinal fluid contained increased protein concentration, IgG, and myelin basic protein. Syndrome of inappropriate secretion of antidiuretic hormone (SIADH) associated with MS was diagnosed. Intravenous Na infusion with restricted supplemental fluid and serial administration of methylprednisolone (1,000 mg/day for three days) improved his neurological abnormalities and normalized his serum serum Na level and plasma osmotic pressure. This suggests that demyelinating lesions in the hypothalamus due to MS may cause the transient increased ADH secretion.

[A variant of Guillain-Barré syndrome with prominent bilateral peripheral facial nerve palsy--facial diplegia and paresthesias].

A patient with Facial diplegia and paresthesias, a rare regional variant of Guillain-Barré syndrome (GBS), is described. A 37-year-old woman developed paresthesias in the distal limbs and subsequently bifacial weakness. She had had a preceding episode of laryngitis. Neurological examination showed severe facial diplegia with loss of taste sensation on the tip of the tongue. Limb muscle power was preserved. Deep tendon reflexes were generally absent. She complained of paresthesias in the distal limbs, but sensory examination was normal. Cerebrospinal fluid showed albuminocytological dissociation. Electrophysiological studies revealed severe facial nerve involvements and demyelinative findings in her limbs. Intravenous immunoglobulin rapidly improved the abnormal sensation in her limbs. Although facial diplegia gradually lessened after the therapy, mild residual weakness was noted 6 months after the neurological onset. To diagnose facial diplegia and paresthesias, it is important to clarify the findings common to typical GBS such as the antecedent illness, acute and monophasic course, distal paresthesias, areflexia, cerebrospinal fluid albuminocytological dissociation, and demyelinative conduction abnormalities in the limbs.

[Cerebral embolism associated with Becker muscular dystrophy-related dilated cardiomyopathy].

A 65-year-old man with previous history of congestive heart failure and genetically proven Becker muscular dystrophy (BMD) was suddenly suffered from aphasia and right hemiplegia. Physical examination showed severe motor aphasia, right hemiplegia, and signs of left heart failure. An echocardiogram before the onset of aphasia showed markedly dilated left ventricle and decreased ventricular contraction. Intracardiac thrombus was not detected. Although his electrocardiogram on admission showed sinus rhythm, atrial fibrillation was noted at the time of neurological deterioration. MRI of the brain revealed acute infarction in the territory of the left middle cerebral artery and the left anterior inferior cerebellar artery. MR angiography showed vascular occlusion at the left M2 segment. Cerebral embolism due to atrial fibrillation associated with BMD-related DCM was diagnosed. While an administration of anti-coagulant, diuretics, and dopamine relieved his respiratory distress and right hemiplegia, severe motor aphasia persisted. Cerebral embolism may be a notable complication in patients with BMD presenting with late-life expression of skeletal muscular weakness and antecedent cardiac involvement.

[Head retraction reflex-like movements with severe bulbar symptoms in a patient with stiff-person syndrome].

A 57-year-old woman developed muscular stiffness and painful cramps, which were relieved by administration of dantrolene sodium. Her serum level of antibodies to glutamic acid decarboxylase (GAD) was markedly elevated and continuous muscular activities were observed on resting surface EMG. These features were compatible with those in stiff-person syndrome (SPS). She was found to have thymoma on CT scan. Immediately after thymomectomy, which was histologically diagnosed as a benign hyperplasia, she developed head retraction reflex-like movements evoked by sensory stimulation to the face, which were followed by severe bulbar symptoms with dysphagia and respiratory arrest. Postoperative myasthenia gravis was excluded clinically. While somatosensory evoked EMG on splenius muscle initially showed biphasic responses with latency of 15 msec and 55 msec, respectively after oral angle non-painful electric stimulation, the late potential phase disappeared after the patient recovered from bulbar symptoms. This suggests that head retraction reflex-like movements of this patient reflected the attenuation of inhibitory potentials from the brainstem.

[Ataxic Guillain-Barré syndrome with delayed facial diplegia].

We described a patient with ataxic Guillain-Barré syndrome who subsequently developed facial diplegia. A 38-year-old man developed ataxia, distal limb paresthesias, mild dysphagia, urinary retention and orthostatic hypotension a week after an episode of laryngitis. He had high titers of serum anti-GQ1b, anti-GD1b, anti-GM1b, anti-GT1a, and anti-GD1a IgG antibodies during the acute phase. Although the initial symptoms markedly improved by intravenous immunoglobulin therapy, asymmetric facial diplegia subsequently occurred and remained longer than ataxia. Similar course of facial nerve palsy has been reported in patients with Fisher syndrome. Common pathophysiological mechanism may function in the development of delayed facial diplegia in Fisher syndrome and ataxic Guillain-Barre syndrome.