Factors predictive of the presence of a CSF1R mutation in patients with leukoencephalopathy.

BACKGROUND AND PURPOSE: The purpose was to identify statistically factors that correlate with the presence of a colony-stimulating factor 1 receptor (CSF1R) mutation and to reevaluate the accuracy of the current diagnostic criteria for CSF1R-related leukoencephalopathy. METHODS: CSF1R testing was conducted on 145 consecutive leukoencephalopathy cases who were clinically suspected of having adult-onset leukoencephalopathy with axonal spheroids and pigmented glia. From these, 135 cases whose detailed clinical information was available were enrolled. Forward logistic stepwise regression was performed to generate a probability model to predict a positive CSF1R mutation result. The current diagnostic criteria were also applied to our cohort and their sensitivity and specificity were calculated. RESULTS: Twenty-eight CSF1R-mutation-positive cases and 107 CSF1R-mutation-negative cases were identified. Our probability model suggested that factors raising the probability of a CSF1R-mutation-positive result were younger onset, parkinsonism, thinning of the corpus callosum and diffusion-restricted lesions. It also showed that involuntary movements and brainstem or cerebellar atrophy were negative predictors of a CSF1R-mutation-positive result. In our cohort, the sensitivity and specificity for 'probable' or 'possible' CSF1R-related leukoencephalopathy were 81% and 14%, respectively. CONCLUSIONS: Clinical and brain imaging features predictive of the presence of a CSF1R mutation are proposed. Consideration of these factors will help prioritize patients for CSF1R testing.

Squatting-induced bilateral peroneal nerve palsy in a sewer pipe worker.

Compression neuropathy of the common peroneal nerve (CPN) at the fibula head is a common condition, but it has not attracted attention in working environments. Here, we report a 38-year-old sewer pipe worker who presented with bilateral CPN palsy following 6h working with a squatting posture in a narrow sewer pipe. During the work, he could not stretch his legs sufficiently because of the confined space. His symptoms deteriorated with repetition of the same work for 1 week. Motor nerve conduction study showed conduction block at the fibula head of bilateral CPNs, compatible with compression neuropathy at this lesion. Three months after cessation of work requiring the causative posture, his symptoms and neurophysiological abnormalities had resolved completely. Almost all seven of his co-workers presented transiently with similar and milder symptoms, although one showed CPN palsy for 6 months. Prolonged squatting posture in a confined space causes acute compression neuropathy at the fibula head in the CPN. More attention should be paid to 'confined space worker's compression neuropathy'.

p.E66Q mutation in the GLA gene is associated with a high risk of cerebral small-vessel occlusion in elderly Japanese males.

BACKGROUND AND PURPOSE: GLA is the causative gene of Fabry disease, an X-linked lysosomal storage disorder resulting from α-galactosidase A (α-GAL) deficiency. Stroke is an important manifestation of Fabry disease, and recent epidemiological studies have indicated that up to 4.9% of young male cryptogenic stroke patients have GLA mutations. To determine the importance of GLA mutations in the general stroke population, the frequency of GLA mutations in Japanese male ischaemic stroke (IS) patients with various risk factors and ages was measured. METHODS: A total of 475 male IS patients (mean age 69.7 ± 12.5 years), were enrolled in this study. A blood sample was obtained to produce blood spots for measurement of α-GAL activity. Blood samples with decreased enzymatic activity were reassayed and the entire GLA gene was analyzed by direct DNA sequencing if α-Gal A activity was consistently low. RESULTS: α-Gal A activity was decreased in 10 men, five of whom (1.1%) had the GLA gene mutation, p.E66Q. All IS patients with p.E66Q mutation had substantial residual α-Gal A activity, in contrast to patients with classic-type Fabry disease. Clinically, all patients with p.E66Q mutation were > 50 years old and had multiple small-vessel occlusions (lacunar infarctions). Statistical analysis using Fisher's exact test showed the allele frequency of GLA p.E66Q in patients with small-vessel occlusion to be significantly higher than that in the general Japanese population [odds ratio (OR) = 3.34, P = 0.025). CONCLUSIONS: GLA p.E66Q mutation is a genetic risk factor for cerebral small-vessel occlusion in elderly Japanese males.

Recent progress in the understanding and treatment of transthyretin amyloidosis.

WHAT IS KNOWN AND OBJECTIVE: Transthyretin (TTR) is a representative amyloidogenic protein in humans. Rate-limiting tetramer dissociation and rapid monomer misfolding and misassembly of variant TTR result in autosomal dominant familial amyloidosis. Analogous misfolding of wild-type TTR results in senile systemic amyloidosis (SSA) presenting as sporadic amyloid disease in the elderly. The objective of this review is to summarize recent progress in our understanding and treatment of TTR amyloidosis. METHODS: Literature searches were conducted on the topics of transthyretin, familial amyloid polyneuropathy and clinical trials, using PubMed, the United States clinical trials directory, pharmaceutical company websites and news reports. The information was collected, evaluated for relevance and quality, critically assessed and summarized. RESULTS AND DISCUSSION: The current standard first-line treatment of familial TTR amyloidosis is liver transplantation. However, large numbers of patients are not suitable transplant candidates. Recently, the clinical effects of TTR tetramer stabilizers, tafamidis and diflunisal, were demonstrated in randomized clinical trials, and tafamidis has been approved for the treatment of FAP in European countries and Japan. In addition, gene therapies with antisense oligonucleotides and small interfering RNAs are promising strategies to ameliorate TTR amyloidoses and are currently in clinical trials. WHAT IS NEW AND CONCLUSIONS: Liver transplantation to treat the familial TTR amyloidosis will likely be replaced by other less invasive therapies, such as TTR tetramer stabilizers and possibly gene therapy approaches. These newly developed therapies are expected to be effective for not only familial TTR amyloidosis but also SSA, based on their mechanisms of action.

Early-onset ataxia with ocular motor apraxia and hypoalbuminemia is caused by mutations in a new HIT superfamily gene.

Friedreich ataxia (FRDA), the most common autosomal recessive neurodegenerative disease among Europeans and people of European descent, is characterized by an early onset (usually before the age of 25), progressive ataxia, sensory loss, absence of tendon reflexes and pyramidal weakness of the legs. We have recently identified a unique group of patients whose clinical presentations are characterized by autosomal recessive inheritance, early age of onset, FRDA-like clinical presentations and hypoalbuminemia. Linkage to the FRDA locus, however, was excluded. Given the similarities of the clinical presentations to those of the recently described ataxia with oculomotor apraxia (AOA) linked to chromosome 9p13, we confirmed that the disorder of our patients is also linked to the same locus. We narrowed the candidate region and have identified a new gene encoding a member of the histidine triad (HIT) superfamily as the 'causative' gene. We have called its product aprataxin; the gene symbol is APTX. Although many HIT proteins have been identified, aprataxin is the first to be linked to a distinct phenotype.

Isolation and characterization of a human alternative complement pathway-inhibiting protein from larval hemolymph of the silkworm, Bombyx mori.

An alternative complement pathway-inhibiting protein (ACPIP), which inhibits the activation of the alternative complement pathway (ACP) of the human serum, was isolated from larval hemolymph of the silkworm, Bombyx mori, by using ammonium sulfate fractionation and column chromatographies to homogeneity. About 400microg of ACPIP was routinely obtained from 20ml hemolymph. The purified ACPIP preparation consisted of two distinct polypeptides (34 and 32kDa) on SDS-PAGE. The amino acid compositions of the two polypeptides were nearly identical; 21% of the amino acid residues were acidic. The amino terminal amino acid sequences up to 20 residues in these two polypeptides were also identical. Addition of the ACPIP to human serum resulted in a dose-dependent inhibition of the hemolysis of intact rabbit erythrocytes via the ACP, whereas in no inhibition of hemolysis of sensitized-sheep erythrocytes (EA) via the classical pathway.

Japanese family with an autosomal dominant chromosome instability syndrome: a new neurodegenerative disease?

We report on a Japanese family having an autosomal dominant neurodegenerative disease with chromosomal instability and radiosensitivity. Clinical manifestations of affected members included short stature, osteoporosis, severe dental caries, and various neurological abnormalities, such as mental retardation, depression, dysarthria, hyperreflexia, and ataxic gait. MRI demonstrated a markedly atrophic spinal cord and degeneration of the white matter. Cytogenetic examination showed spontaneous chromosome rearrangements at 14q11.2 and hypersensitivity to radiation and bleomycin. The degree of these cytogenetic abnormalities was significantly higher in the patients than in normal controls but lower than in patients with ataxia telangiectasia or Nijmegen breakage syndrome. Moreover, genetic anticipation was observed in this family: the age of disease onset became earlier, MRI abnormalities more extensive, and the chromosome hypersensitivity to radiation increased in successive generations. We speculate that a basic defect in this family is a mutation in the gene that is responsible for DNA double-strand breakage repair.

Serum transthyretin monomer in patients with familial amyloid polyneuropathy.

Although dissociation of the transthyretin (TTR) tetramer is suspected of being the first step in amyloid fibril formation in hereditary TTR amyloidosis, including familial amyloid polyneuropathy (FAP), the TTR monomer has never been examined in vivo. Therefore, we analyzed the TTR monomer in the serum of FAP patients and normal individuals. Free TTR monomer was detected in both groups using gel filtration chromatography and immunoblotting. Both the mean concentration of free TTR monomer and the total serum TTR were significantly lower in FAP patients than in normal individuals. Moreover, in FAP patients, mass spectrometry showed that the variant TTR monomer was markedly decreased compared with the wild-type TTR monomer. These findings suggest that the free variant TTR monomer is unstable in serum, and that it aggregates in deposits in various organs or is adsorbed by preexisting amyloid fibrils before it is degraded

Presenilin-1 exists in the axoplasm fraction in the brains of aged Down's syndrome subjects and non-demented individuals.

Missense mutations in the presenilin-1 (PS-1) gene are known to be responsible for early-onset familial Alzheimer's disease (AD). The normal physiological functions of PS-1 are still incompletely understood, although data on the intracellular localization of PS-1 are accumulating, indicating that it exists mainly in endoplasmic reticulum and Golgi compartments. To investigate the localization and functions of PS-1 in the human brain, we separated axoplasm fractions from the cerebral white matter of Down's syndrome (DS) subjects with AD pathology and non-demented individuals using the axonal flotation method, and analyzed them immunocytochemically. All axoplasm fractions contained the 28-34 kDa amino-terminal fragment and the 18 kDa carboxy-terminal fragment of PS-1, although there was no specific abnormality of this protein in the DS brains with AD pathology. This finding indicates that there is intracellular trafficking of PS-1 through the axons in the human brain, and thus provides new information about the physiology of PS-1.

No association between apolipoprotein E epsilon4 allele and the age of onset in type I familial amyloid polyneuropathy.

It has been shown that the Apolipoprotein E (ApoE) epsilon4 allele increases the risk of developing Alzheimer's disease (AD) and lowers the age of its onset. ApoE has also been suggested to be a common facilitating factor in the different types of amyloidoses. However, the association of ApoE epsilon4 with the onset of disease in various types of amyloidoses has not been extensively investigated. Type I familial amyloid polyneuropathy (FAP) is one form of systemic amyloidosis in which ApoE co-localizes with amyloid deposits. We examined 54 patients with type I FAP and found that there was no significant effect of either ApoE epsilon2 or epsilon4 allele on the age at onset. Our results suggest that ApoE4 is not a facilitating factor in the development of FAP, transthyretin amyloidosis.

Hereditary motor and sensory neuropathy associated with cerebellar atrophy (HMSNCA): clinical and neuropathological features of a Japanese family.

We report clinicopathological features of a Japanese family with hereditary motor and sensory neuropathy associated with cerebellar atrophy (HMSNCA). Four affected members from a single generation were examined. They shared common clinical features, including insidious onset in teenage, slowly progressive cerebellar ataxia, amyotrophy, sensory disturbance, and dementia. In addition, all the patients showed hypoalbuminemia and hyperlipidemia and a marked atrophy of the cerebellum on magnetic resonance images. Autopsy of the proband revealed a severe loss of Purkinje cells, degeneration of posterior columns and spinocerebellar tracts of the spinal cord, and a marked loss of myelinated and unmyelinated fibers in the peripheral nerves. We consider that HMSNCA is a distinct form of hereditary multisystem neuronal degeneration.

Remitting seronegative symmetrical synovitis with pitting edema (RS3PE) syndrome in Nagano, Japan: clinical, radiological, and cytokine studies of 13 patients.

OBJECTIVE: Remitting seronegative symmetrical synovitis with pitting edema (RS3PE) has so far been reported almost exclusively from the USA and Europe. We carried out this study to define the clinical characteristics of this syndrome in Japanese patients. METHODS: Prospectively, we identified 13 Japanese patients with RS3PE (5 men and 8 women, age 72.7 +/- 11.8 years (mean +/- SD)) without underlying neoplasm. Their clinical features were summarized, pertinent laboratory data including serum/synovial interleukin-6 (IL-6) concentrations were obtained, and extensive radiologic studies using magnetic resonance imaging and 67gallium-citrate (67Ga) whole body scintigram were performed. RESULTS: All patients suffered from proximal arthralgia/myalgia in addition to typical distal symptoms of RS3PE, and all experienced systemic symptoms such as fever, malaise, and weight loss. In laboratory examinations, anemia and elevated inflammatory markers were often remarkable. Magnetic resonance imaging showed severe tenosynovitis of the hands. 67Ga-scintigram revealed radioisotope accumulation in both proximal and distal joints of the extremities. IL-6 activity was markedly elevated both in the serum (mean 82.4 +/- 62.1 (SD) pg/ml, normal range 0.157-2.94) and in the synovial fluid (mean 3350 +/- 633 (SD) pg/ml). CONCLUSION: Compared with cases reported previously from the USA/Europe, Japanese patients with RS3PE are characterized by more prominent systemic symptoms/signs associated with marked inflammatory responses including elevated IL-6 activity. All patients had proximal as well as distal synovitis which could be demonstrated by 67Ga-scintigram. These clinical features were very similar to those of polymyalgia rheumatica, suggesting that RS3PE and polymyalgia rheumatica are closely related disorders which may have a common pathogenesis.

Three patients with isolated adrenocorticotropin deficiency presenting with neuroleptic malignant syndrome-like symptoms.

We report 3 patients with isolated adrenocorticotropin (ACTH) deficiency presenting with neuroleptic malignant syndrome (NMS)-like symptoms. All patients were in their 60's or 70's and showed consciousness disturbance, a high-grade fever, extrapyramydal signs, and muscle enzyme elevations, which met the criteria for NMS. Also, they all showed hyponatremia induced by isolated ACTH deficiency. In addition to the standard therapy for NMS, corticosteroid supplement therapy was effective in all patients. There thus appear to be subjects with isolated ACTH deficiency among patients presenting with NMS-like symptoms, and adrenal and pituitary function should be checked in NMS patients with hyponatremia.

Cytoplasmic body myopathy with hypertrophic cardiomyopathy.

A patient with cytoplasmic body myopathy presented muscle hypotonia from birth and developed progressive muscular atrophy and weakness, scoliosis, contracture of joints and cardiorespiratory failure. At the age of 17, he died of heart failure. Post mortem examination revealed severe hypertrophy of cardiac walls and generalized muscular atrophy. Microscopic examination showed many cytoplasmic bodies in skeletal muscle fibers and myofiber disarray in myocardium. No cases of cytoplasmic body myopathy with hypertrophic cardiomyopathy have been reported previously. It is suggested that the Z-line component is related to the formation of the cytoplasmic body in skeletal muscle and disarray in the cardiac muscle.

Sleep apnoea of central origin in a case of myotonic dystrophy.

We report the case of a 46-year-old male with myotonic dystrophy who developed daytime hypersomnia and dyspnoea. After a therapeutic tracheostomy, overnight polysomnographic studies were performed under three different ventilatory conditions. When the patient breathed spontaneously through a tracheal cannula, abnormal cyclical sleep increased and rapid eye movement (REM) sleep decreased markedly. The apnoea and hypopnoea index (AH index) was 35.1. When breathing spontaneously through his normal airway, there were many instances of cyclical sleep, but few instances of deep sleep and no episodes of REM sleep. The AH index was 58. Under assisted ventilation the patient's sleep pattern was normal. Our conclusion, therefore, is that these studies demonstrate the patient had sleep apnoea of central origin.

[A case of chronic inflammatory demyelinating polyradiculoneuropathy complicated by phrenic nerve palsy].

We report on a patient with chronic inflammatory demyelinating polyradiculoneuropathy (CIDP) complicated by phrenic nerve palsy. A 50-year-old man was admitted to our hospital due to dyspnea and numbness in his limbs. On admission, severe muscle atrophy, weakness, and sensory disturbance were seen in the distal part of his extremities. Deep tendon reflexes were absent in all the limbs. Routine blood examinations showed no abnormal findings except for mild hyperglycemia (fasting blood sugar 145 mg/dl). Right phrenic nerve palsy was observed on a chest roentgenogram and % vital capacity (%VC) was 56%. Cerebrospinal fluid showed elevated levels of total protein (116 mg/dl) and IgG (16.9 mg/dl). Sural nerve biopsy revealed severe loss of myelinated fibers with demyelination and onion-bulb formation. After immunoadsorption plasmapheresis, the phrenic nerve palsy improved rapidly and %VC recovered to 76%. Although phrenic nerve palsy is rare in patients with CIDP, it is important to take notice of this condition, because phrenic nerve palsy is critical when it occurs bilaterally or when it develops in patients who have suffered from respiratory diseases. Immunoadsorption plasmapheresis is one of the effective treatments for CIDP, especially in patients with serious complications such as phrenic nerve palsy.

[A case of idiopathic brain calcification associated with dyschromatosis symmetrica hereditaria, aplasia of dental root, and aortic valve sclerosis].

The patient was a 23-year-old woman. She was the product of a full-term pregnancy and normal delivery. At age 3, she was observed to have eruptions on the face and extremities. Gait disturbance and abnormal posture appeared when she was 17-year-old. Mental deterioration followed several years later, and these symptoms progressed gradually. On examination at age 23, mixture of hyperpigmented and hypopigmented macules were observed on the face and the dorsal aspects of the extremities. We diagnosed her skin lesion as dyschromatosis symmetrica hereditaria (DSH) based on dermatological findings, normal minimal erythema dose and normal unscheduled DNA synthesis of her skin fibroblasts. Neurologically, she showed moderate mental deterioration, dystonic posture, dystonic and spastic gait, and generalized hyperreflexia. Laboratory examinations, including parathyroid function, were normal. Brain CT scan revealed severe symmetrical calcifications in the basal ganglia, cerebral white matter, and dentate nucleus. She also showed aplasia of dental root and aortic valve sclerosis. Her father also revealed the same clinical features including skin lesion, movement disorder, mental deterioration, and severe aortic valve calcification. So we diagnosed this patient as familial idiopathic brain calcification associated with DSH, aplasia of dental root, and aortic valve sclerosis. Constellation of these clinical features does not match any previously established type of familial idiopathic brain calcification or hereditary dystonia. However, Patrizi et al reported a patient with DSH associated with torsion dystonia who was very similar to our patient. We propose that our patient and the patient reported by Patrizi et al construct a distinct clinical entity in familial idiopathic brain calcification or hereditary dystonia.

[A case of severe status epilepticus of frontal lobe origin successfully treated with corticosteroids].

A 17-year-old girl was admitted to our hospital due to low-grade fever, confusion, numbness in her right hand and automatism. On admission, she was slightly disoriented but there were no meningeal signs. Weakness and sensory disturbance were observed in her right hand. Automatism and clonic seizures frequently appeared. Electroencephalography revealed frequent delta bursts in her left frontal lobe. 123I-IMP-SPECT study showed abnormally increased isotope uptake in the left cerebral hemisphere. She was diagnosed as status epilepticus of left frontal lobe origin and treated with anti-convulsants including carbamazepine, phenytoin, diazepam, phenobarbital, and thiopental, which were not effective. Then we started corticosteroid therapy. Three cycles of intravenous injections of methylprednisolone, followed by oral prednisolone led to marked improvement in her symptoms. It is known that corticosteroid decreases the threshold of seizure, so we do not use it for idiopathic epilepsy. On the other hand, in some secondary epilepsy due to vasculitis in the brain, corticosteroid is very effective for seizures. It is still unclear whether our patient actually had vasculitis or not. However, it is important to recognize that steroid therapy might be effective in a certain portion of epilepsies resistant to anti-convulsants, especially in young patients with non-infectious fever.

[A case of severe sarin poisoning in the sarin attack in Matsumoto--one-year follow-up of clinical findings, and laboratory data].

A patient severely poisoned with sarin in the Sarin Attack in Matsumoto is described. A 19-year-old man was exposed to sarin at 23:00 on 27 June, 1994. At 1:00 of the following day, a rescue team found and brought him to the hospital. His blood pressure was 150-80mmHg and the heart rate was 120/min with frequent premature ventricular contractions (PVC). His respiration was shallow and copious salivation and excretion from the respiratory tract were observed. Consciousness disturbance, generalized convulsion, severe miosis and fasciculation of tongue, facial muscle and extremities were also marked. Serum cholinesterase was 21 U/l (normal 109-249) and acetylcholinesterase in erythrocyte (E-AchE) was 0.1U/l (normal 1.2-2.0). Electroencephalogram (EEG) 30 hours after exposure showed polispike and wave complexes. Ventilatory assistance, forced urination and injection of diazepam and atropin improved his general condition and he was discharged 18 days after exposure. Three months after exposure, E-AchE was normalized and there was no complaint. But one year after exposure, EEG showed epilecpic discharges during sleep, and Holter electrocardiogram showed frequent PVC. As no clinical cases of severe sarin poisoning like this patient was reported, a longterm follow-up of this patient is very important.