Juvenile-onset neuronal ceroid lipofuscinosis with infantile CLN1 mutation and palmitoyl-protein thioesterase deficiency

Accurate diagnosis, especially in progressive hereditary diseases, is essential for the treatment and genetic counseling of the patient and the family. Neuronal ceroid lipofuscinoses (NCL) are amongst the most common groups of neurodegenerative diseases. Infantile, juvenile, and adult-onset types with multiple genotype-phenotype associations have been described. A fluorimetric enzyme assay for palmitoyl protein thioesterase (PPT) from leukocytes and fibroblasts has been previously developed to confirm the diagnosis of infantile NCL. We describe a patient with juvenile-onset NCL phenotype with a new CLN1 mutation and deficient PPT activity. Over 40 different mutations have been found in patients with PPT deficiency, indicating that screening for known mutations is not an efficient way to diagnose this disorder. Therefore, PPT enzyme analysis should precede mutation analysis in suspected PPT deficiency, particularly in patients with granular osmiophilic deposits (GROD) or in patients who have negative ultrastructural data. The use of enzyme assay led to the diagnosis of this patient with juvenile-onset Finnish variant NCL with PPT deficiency, and we expect that greater awareness of the utility of the enzymatic assay may lead to identification of other similar cases awaiting a definitive diagnosis.

Neuroradiological findings (MRS, MRI, SPECT) in infantile neuronal ceroid-lipofuscinosis (infantile CLN1) at different stages of the disease

Infantile neuronal ceroid-lipofuscinosis (infantile CLN1) is a progressive and uniformly fatal lysosomal storage disease of the nervous system. The purpose of this study was to compare the findings of various radiological examinations of the brain in the course of infantile CLN1 in order to evaluate the relative usefulness of the methods and their potential for monitoring therapeutic interventions. We examined eight infantile CLN1 patients, 51 studies, in various stages of the disease--preclinical to late stage--with proton magnetic resonance spectroscopy (1H-MRS), MRI, and perfusion SPECT, and in addition three benzodiazepine (BZ) receptor ligand SPECT studies. Both 1H-MRS and MRI showed abnormal findings before clinical manifestations of the disease. Cortical hypoperfusion and loss of cortical BZ receptors revealed by SPECT appeared simultaneously with clinical signs. After the age of 4 years MRI and SPECT alterations progressed minimally, whereas 1H-MRS showed progressive deterioration of neurometabolism. Of the four methods used in this study, MRI proved to be the most practicable for diagnosing infantile CLN1; the final diagnosis of infantile CLN1 is confirmed by the characteristic clinical picture and DNA or PPT enzyme analysis. The combination of 1H- MRS and MRI could be most useful for monitoring therapeutic interventions.

Enlarged SI and SII somatosensory evoked responses in the CLN5 form of neuronal ceroid lipofuscinosis

OBJECTIVES

To examine in detail the activation of the primary (SI) and secondary (SII) somatosensory cortex in CLN5, the Finnish variant of late infantile neuronal ceroid lipofuscinoses (NCL).

METHODS

Somatory evoked magnetic fields were recorded with a 122-channel planar gradiometer in response to median nerve stimulation in 5 CLN5 patients (aged 8.8-16.7 years) and in 10 healthy age-matched controls.

RESULTS

The first two responses from contralateral SI, N20m and P35m, were 6-20 times stronger in the patients than in the controls. The morphology of the subsequent deflections from SI was abnormal in the patients: a prominent N45m was detected, while the normally present P60m deflection was missing. In 4 patients the contra- and in two patients the ipsilateral SII responses were also enlarged. Furthermore, the SII activation was detected at shorter latency in patients than in controls.

CONCLUSIONS

At SI, CLN5 is associated with a selective enhancement of the early cortical responses. We propose that the enlargement of N20m most likely reflects increased synchronous input from thalamus, whereas the altered morphology of the following responses may reflect defective interneuronal inhibition at the cortex. The enlargement of SII responses shows that the imbalance between excitation and inhibition in CLN5 extends outside the primary somatosensory areas.

Positron emission tomography shows reduced striatal dopamine D1 but not D2 receptors in juvenile neuronal ceroid lipofuscinosis

We studied striatal dopamine D1 and D2 receptors in patients with juvenile neuronal ceroid lipofuscinosis (JNCL) with positron emission tomography (PET) using a dopamine D1 receptor antagonist [11C]NNC 756 and a dopamine D2 receptor antagonist [11C]raclopride as ligands. The mean [11C]NNC 756 uptake value in JNCL was reduced by 15 % from the mean control value in the putamen (p < 0.01) and by 13 % in the caudate nucleus (p < 0.01). The mean [11C]raclopride uptake in JNCL patients was not significantly different from the mean of the control group either in the putamen or the caudate nucleus. Our results show a mild reduction in striatal dopamine D1 but not in D2 receptors in JNCL, indicating slightly impaired striatal neuronal function. The contribution of these changes to the extrapyramidal symptoms of the patients and their treatment deserves further studies.

Hematopoietic stem cell transplantation in infantile neuronal ceroid lipofuscinosis

OBJECTIVE

To study the effect of allogeneic hematopoietic stem cell transplantation (SCT) on the clinical course of infantile neuronal ceroid lipofuscinosis (INCL), a lysosomal storage disease.

BACKGROUND

INCL is a progressive encephalopathy with severe neuronal loss, especially in the cerebral and cerebellar cortex and retina. Autofluorescent lipopigments constitute the typical storage material in INCL. The disease is caused by recessive mutations in the palmitoyl protein thioesterase 1 (PPT1) gene. PPT1 is a depalmitoylating enzyme, which is transported to lysosomes through the mannose-6-phosphate receptor-mediated pathway, and participates in the lysosomal degradation of fatty acylated proteins.

METHODS

Three patients with INCL received transplants and were followed up after SCT at the Hospital for Children and Adolescents at the University of Helsinki. The first patient rejected the first graft at the age of 7 months and had mild symptoms of INCL at the second transplantation at 11 months. The two other patients were asymptomatic when they received their transplants at the age of 4 months.

RESULTS

PPT1 enzyme activity was normalized in peripheral leukocytes, but remained low in the CSF and resulted only in a mild and transient amelioration of the classic INCL. All patients who received transplants developed INCL by the age of 2 or 3 years.

CONCLUSIONS

More experimental animal and cell culture studies are needed to determine the in vivo function of PPT1. SCT currently cannot be recommended as therapy for INCL.

Sleep and its disturbance in a variant form of late infantile neuronal ceroid lipofuscinosis (CLN5)

To examine the nature of sleep disturbance in patients with a variant form of late infantile neuronal ceroid lipofuscinosis (CLN5), we studied 12 patients (age range 7-32 years). We used a sleep questionnaire to assess sleep and its disturbances quantitatively. To identify the periodicity in the diurnal rest-activity rhythms, the motor activity level was recorded by activity monitors continuously for a 1-week period with concomitant sleep logs. In addition, whole-night polysomnographic recordings were performed. The patients under 20 years of age had an excess of nocturnal sleep (the mean of the usual duration of nighttime sleep was 10.0 hours) and frequent daytime naps. Frequent shifts of the longest sleep period into the daytime hours and fragmented diurnal rest-activity patterns with no distinct rhythm occurred in the older patients. The progressive disease may damage the internal circadian timing system and also impair the ability of patients with variant late infantile neuronal ceroid lipofuscinosis to use external time cues for synchronization of their sleep and environmental time.

A favorable response to antiparkinsonian treatment in juvenile neuronal ceroid lipofuscinosis

To study the effect of dopaminergic drugs on the parkinsonism in juvenile neuronal ceroid lipofuscinosis, the authors conducted an open study of 21 patients. According to the motor Unified PD Rating Scale (UPDRS) score, treatment was initiated with either levodopa (n = 10) or selegiline (n = 6). Five patients served as a control group. The UPDRS score after 1 year was compared with the score at onset. Both in the control group and in the selegiline group, the mean UPDRS score increased, whereas in the levodopa group, the mean UPDRS score decreased. The difference between the levodopa group and the control group was significant.

Clinical and genetic distinction between Walker-Warburg syndrome and muscle-eye-brain disease

BACKGROUND

Three rare autosomal recessive disorders share the combination of congenital muscular dystrophy and brain malformations including a neuronal migration defect: muscle-eye-brain disease (MEB), Walker-Warburg syndrome (WWS), and Fukuyama congenital muscular dystrophy (FCMD). In addition, ocular abnormalities are a constant feature in MEB and WWS. Lack of consistent ocular abnormalities in FCMD has allowed a clear clinical demarcation of this syndrome, whereas the phenotypic distinction between MEB and WWS has remained controversial. The MEB gene is located on chromosome 1p32-p34.

OBJECTIVES

To establish distinguishing diagnostic criteria for MEB and WWS and to determine whether MEB and WWS are allelic disorders.

METHODS

The authors undertook clinical characterization followed by linkage analysis in 19 MEB/WWS families with 29 affected individuals. With use of clinical diagnostic criteria based on Finnish patients with MEB, each patient was categorized as having either MEB or WWS. A linkage and haplotype analysis using 10 markers spanning the MEB locus was performed on the entire family resource.

RESULTS

Patients in 11 families were classified as having MEB and in 8 families as WWS. Strong evidence in favor of genetic heterogeneity was obtained in the 19 families. There was evidence for linkage to 1p32-p34 in all but 1 of the 11 pedigrees segregating the MEB phenotype. In contrast, linkage to the MEB locus was excluded in seven of eight of the WWS families.

CONCLUSION

These results allow the classification of MEB and WWS as distinct disorders on both clinical and genetic grounds and provide a basis for the mapping of the WWS gene(s).

Neuronal ceroid lipofuscinoses in childhood

NCL disorders are progressive brain diseases with an autosomal recessive inheritance in all eleven childhood types. These occur world-wide but may be enriched in some countries. In Finland altogether about 400 patients have been diagnosed during the last forty years. The most common types are the infantile and classic juvenile forms with an incidence of 1: 20,000 and 1: 21,000, respectively Personally followed-up are patients with infantile, classic and Finnish variant late infantile and classic juvenile types. Clinical, neurophysiological and neuroimaging findings in these four NCL forms are reviewed including also management and diagnostic aspects.

A child with muscle-eye-brain disease. Ophthalmological and neurological characteristics

PURPOSE

To describe a child with Muscle-Eye-Brain disease (MEB), one of three types of congenital muscular dystrophy associated with ocular abnormalities.

METHODS

Case report.

RESULTS

The child showed severe visual impairment due to progressive myopia and retinal degeneration, a pachygyria-type of migration disorder of the brain with a nodular cortical surface, i.e. cobblestone cortex, as well as muscular weakness and severe mental retardation.

CONCLUSION

Ophthalmological assessments are important to help to diagnose and follow children with congenital muscular dystrophy.

Neuropsychological test battery in the follow-up of patients with juvenile neuronal ceroid lipofuscinosis

The aim of the present study was to develop a neuropsychological test battery for patients with juvenile neuronal ceroid lipofuscinosis (JNCL) and to study the development of cognitive functions during the first 5 years after diagnosis. Fourteen patients with JNCL entered the study. Nine patients were homozygous for the major mutation, whereas five were compound heterozygotes. All patients were studied annually with a special neuropsychological test battery (NEPSY) adapted from Luria's neuropsychological test, and modified for the visually handicapped; the Wechsler Intelligence Scale for Children - Revised (WISC-R) was also included. The neurological examinations were scored. Furthermore, 1.OT magnetic resonance imaging scan was performed at the beginning of follow-up and after a mean of 5 years. A decline in verbal IQ (WISC-R) during the follow-up period was found in all subjects except one compound heterozygous male. Short-term memory and digit memory span were already impaired at an early stage of the disease. Orientation to time was found to decline more than orientation to person and place. Motor speed usually became impaired after 10 years of age. Spatial orientation was impaired only in the patients homozygous for the major mutation. The test battery was found to be reliable and easy to use, and offered valuable information on the progress of the disease. It also provided important guidelines for rehabilitation.

Studies of homogenous populations: CLN5 and CLN8

Finland and the Finns have been the subject of numerous genetic and genealogical studies, owing to enrichment of certain rare hereditary disorders in the Finnish population. Two types of NCL have so-far been found almost exclusively in Finland: Finnish variant late infantile NCL, vLINCL (CLN5), and the Northern epilepsy syndrome or Progressive epilepsy with mental retardation, EPMR (CLN8). The first symptoms of Finnish vLINCL are concentration problems or motor clumsiness by 3 to 6 years of age, followed by mental retardation, visual failure, ataxia, myoclonus, and epilepsy. Northern epilepsy, the newest member of the NCL family with the most protracted course, is characterized by the onset of generalized seizures between 5 and 10 years of age and subsequent progressive mental retardation. Visual problems are slight and late, while myoclonus has not been observed. Both the Finnish vLINCL and Northern epilepsy are pathologically characterized by intraneuronal cytoplasmic deposits of autofluorescent granules which are Luxol fast blue-, PAS-, and Sudan black B-positive in paraffin sections. In Northern epilepsy the intraneuronal storage process and neuronal destruction are generally of mild degree but highly selective and, in contrast to other forms of childhood onset NCL, the cerebellar cortex is relatively spared. By electron microscopy the storage bodies mainly contain rectilinear complex type and fingerprint profiles in Finnish vLINCL and structures resembling curvilinear profiles in Northern epilepsy. Mitochondrial ATP synthase subunit c is the main stored protein in both disorders. Both the DCLN5 and CLN8 genes encode putative membrane proteins with yet unknown functions. Furthermore, a well studied spontaneously occurring autosomal recessive mouse mutant, motor neuron degeneration (mnd) mouse, is a homolog for CLN8.

Northern epilepsy syndrome (NES, CLN8)--MRI and electrophysiological studies

Northern epilepsy syndrome (NES, EPMR, progressive epilepsy with mental retardation, CLN8), an inherited childhood-onset epilepsy with mental retardation, has been recently characterized to belong to the family of neuronal ceroid lipofuscinoses (NCLs). In this study, four patients (ages 26-44 years) with NES and eight healthy controls underwent magnetic resonance imaging (MRI) and electrophysiological evaluation with somatosensory evoked magnetic field (SEF) studies. The findings in NES were compared with the known findings in juvenile NCL (JNCL, CLN3) and Finnish variant late infantile NCL (vLINCLFIN, CLN5) that manifest around the same age as NES. Also postmortem MRI was performed on one brain. On the MRIs, slight to moderate cerebellar atrophy was seen in all patients, whereas only two patients had slightly enlarged cerebral sulci. None of the MRIs demonstrated signal intensity abnormalities that are commonly seen in JNCL and vLINCLFIN and are considered to reflect the Wallerian degeneration after neuronal death. Generally SEFs in NES were within normal limits, indicating that the disease had not impaired the function of the neurons on the somatosensory pathway. In conclusion, MRI imaging and SEF findings suggest that the cerebral neuronal death and dysfunction in NES are minimal compared with JNCL and vLINCLFIN.

Electroencephalography in juvenile neuronal ceroid lipofuscinosis: visual and quantitative analysis

Fourteen patients with a confirmed diagnosis of juvenile neuronal ceroid lipofuscinosis (JNCL) (aged 6-12.5 years at the beginning of the study) were prospectively followed for 5 years. An electroencephalogram (EEG) was recorded and analysed both visually and quantitatively and a neuropsychological examination was performed once a year. In addition, a cross-sectional EEG study of 32 patients aged 5-27 years was performed. The EEG was often normal before the age of 9 years, and thereafter a progressive background abnormality and increase in paroxysmal activity took place. The EEGs were significantly slower than those of the controls, and the speed of slowing of EEG correlated to the decrease in intelligence quotients (IQ). Quantitative analysis was superior to visual analysis in detecting the deterioration of the background activity. The best parameter describing this was the fast/slow ratio. Peak frequency, percentage of theta and the fast/slow ratio correlated with IQ.

Clinical and neuroradiological diagnostic aspects of neuronal ceroid lipofuscinoses disorders

Early diagnosis is mandatory for avoiding further cases in families with hereditary metabolic brain disorders. This review lists the most important clinical symptoms and neuroradiological findings at the early stage of the seven most common childhood neuronal ceroid lipofuscinoses (NCL) types. In the infantile type the typical magnetic resonance imaging (MRI) findings can be seen even before the clinical signs. In the classic late infantile type (CLN2), MRI is less informative but in this and in the variant late infantile type CLN6 the characteristic neurophysiological findings are present at an early stage, although not in the Finnish variant CLN5. In the latter, the clinical diagnosis depends on ophthalmological and MRI findings. The combination of ophthalmological deficits and vacuolated lymphocytes is highly characteristic of the juvenile type (CLN3). A new NCL type, Northern epilepsy (CLN8), is also briefly reviewed.

Epilepsy and antiepileptic drug therapy in juvenile neuronal ceroid lipofuscinosis

PURPOSE

To survey the characteristics of epilepsy in patients with juvenile neuronal ceroid lipofuscinosis (JNCL) and determine the antiepileptic drug (AED) treatment most suitable for these patients.

METHODS

The study included 60 patients with JNCL; their mean age was 16.5 years (range 5-33). The age at onset of epilepsy, type of seizures, effect of the first AED on seizures, and the current seizure frequency and AED therapy were studied. The side effects of the AEDs were also clarified.

RESULTS

Fifty of the 60 patients had epilepsy. Patients' first epileptic seizure occurred at a mean age of 10.0 years (range 5-16), the most common type being generalized seizures. As the first AED tried, valproate (VPA) and lamotrigine (LTG) appeared equally effective, with 80% of the patients responding to these AEDs. During the study year, the median seizure frequency was four seizures a year (range 0-120), and 72% of the patients had good or satisfactory seizure control (0-6 seizures a year). In the different AED therapy groups, the proportion of patients with good or satisfactory seizure control ranged from 25% to 100%. LTG in monotherapy or in combination with clonazepam (CZP) was superior to other AEDs or combinations, but VPA also seemed effective. Adverse effects leading to the discontinuation of an AED were observed in 25% of the patients, most frequently in patients receiving phenobarbital (PB). No patient receiving LTG had to discontinue the drug due to adverse effects.

CONCLUSION

Epilepsy in JNCL can usually be successfully treated with the current AEDs. In Finnish patients with JNCL, treatment is based on LTG, or, secondarily, VPA. In combination therapy, CZP seems a valuable add-on AED.

Phenotype-genotype correlation in eight patients with Finnish variant late infantile NCL (CLN5)

The authors analyzed the clinical phenotype, including MRI, of eight patients with Finnish variant late infantile neuronal ceroid lipofuscinosis (vLINCLFin; CLN5; MIM256731). Although the four known mutations, including one novel mutation identified in this study, have very different consequences for the predicted polypeptide, none of them results in an atypical phenotype, as has been reported in other forms of NCL. Thus, it seems likely that each mutation severely disturbs the normal function of the CLN5 protein.

CSF insulin-like growth factor-1 in infantile neuronal ceroid lipofuscinosis

BACKGROUND

Infantile neuronal ceroid lipofuscinosis (INCL) is a progressive encephalopathy in which the patients are severely disabled by the age of 3 years. It is characterized by cerebral atrophy, selective loss of cortical neurons, and secondary loss of axons and myelin sheaths of the white matter. INCL has been shown to result from a palmitoyl protein thioesterase deficiency. The authors suggested that insulin-like growth hormones and apoptosis might play a role in the pathogenesis of INCL.

METHODS

The authors measured insulin-like growth factor-1 (IGF-1) and IGF binding protein 3 (IGFBP-3) in the CSF of patients with INCL by radioimmunoassay at an early stage when myelin was starting to diminish.

RESULTS

The authors found low CSF IGF-1 but normal IGFBP-3 in patients with INCL compared with control subjects. Also, they observed apoptotic cell death in biopsies of INCL patients.

CONCLUSIONS

Because the IGF system seems to be important for early brain development, myelination, and neuroprotection, the authors suggest that the pathology in INCL may be associated with low CSF IGF-1.

Sleep alterations in juvenile neuronal ceroid-lipofuscinosis

In juvenile neuronal ceroid-lipofuscinosis (JNCL), sleep disorders are common. The purpose of this study was to investigate the sleep structure of 28 patients with JNCL compared with healthy controls subjects and to clarify the pathophysiology underlying the sleep disturbances in these patients. Each of 28 patients with JNCL (age range = 6-27 years), with or without sleep complaints, underwent one night of polysomnography. Electroencephalographic, electro-oculographic, electromyographic, and electrocardiographic findings were recorded. Sleep was scored and analyzed visually. The sleep parameters of the patients were compared with those of healthy control subjects. In most of the patients, the total sleep time, sleep efficiency, and percentages of rapid eye movement (REM) and non-REM (NREM) stage 2 sleep were significantly decreased, and the percentages of NREM stage 1 and slow-wave sleep and the number of nocturnal awakenings significantly increased. The percentage of NREM stage 1 and the number of awakenings increased with age and clinical stage. Paroxysmal epileptiform activity during light sleep (NREM stages 1-2) and high-amplitude delta-wave activity with intermingled sharp waves during slow-wave sleep were characteristic of the recordings. The present study revealed that in patients with JNCL, sleep is consistently altered.

Decreased striatal dopamine transporter density in JNCL patients with parkinsonian symptoms

OBJECTIVE

To explore whether striatal dopamine transporters are involved in juvenile neuronal ceroid lipofuscinosis (JNCL) with extrapyramidal signs.

METHODS

Seventeen patients with JNCL entered the study (mean age, 15 years; age range, 10 to 31 years). For clinical evaluation, the authors used the motor section of the Unified Parkinson's Disease Rating Scale (UPDRS). For studying the density of dopamine transporters in the striatum, they employed iodine-123-labeled 2beta-carbomethoxy-3beta-(4-iodophenyl) tropane as a SPECT tracer. The SPECT images were evaluated visually, and tracer accumulation was semiquantified from transverse slices as striatum-to-cerebellum activity ratios. MRI (1.5-T) signal intensities of the striatum were measured and compared with those of the thalamus.

RESULTS

The mean UPDRS score was 20 (range, 2 to 41). On SPECT, the mean striatum-to-cerebellum uptake ratio was lower in patients than in control subjects (3.1 +/- 0.6 versus 6.8 +/- 1.0; p < 0.001), with the decrease being more pronounced in the putamen than in the caudate nucleus. On MRI, the mean striatum-to-thalamus signal intensity ratio was higher in patients than in control subjects (1.14 +/- 0.02 versus 1.08 +/- 0.02; p < 0.001). There was a negative correlation between uptake ratios in SPECT and UPDRS scores, and a positive correlation between the MRI ratios and UPDRS. The SPECT and MRI ratios also correlated significantly, providing additional evidence for the contributions of nigrostriatal, striatal, and thalamic dysfunction to the parkinsonian symptoms.

CONCLUSIONS

The observed decrease in the striatal dopamine transporter density in JNCL offers a rational basis for a trial of dopaminergic drugs in this disease.

Muscle membrane-skeleton protein changes and histopathological characterization of muscle-eye-brain disease

Muscle-eye-brain disease belongs to congenital muscular dystrophies with central nervous system abnormalities. The etiology of MEB is still unknown, but abnormal immunoreactivity for laminin-2 has been reported. To evaluate disease progression in muscle tissue, 32 biopsy specimens from 17 muscle-eye-brain patients were analysed. The samples of four patients were studied by immunohistochemical techniques and by quantitative Western blotting. The samples showed a great variation in the muscle pathology. Regenerative fibers and mild fiber size variation were present in over 60%. At infancy, necrotic and regenerative fibers were common, while fat infiltration was the most prominent finding in the age group over five years. In quantitative studies, the amount of laminin alpha 2 chain was clearly reduced to 10-20% of normal. In contrast, laminin beta 2 chain was overexpressed in the Western blotting studies. These findings may reflect a yet unidentified primary disturbance in the basement membrane composition and function.

Bone marrow transplantation in aspartylglucosaminuria--histopathological and MRI study

This study comprised two patients with aspartylglucosaminuria (AGU), who were followed up for 4 and 7 years. The patients underwent allogeneic bone marrow transplantation (BMT) at the ages of 2 and 2.6 years. Both patients had abnormal speech development and gross motor clumsiness. At the time of the BMT, they were mentally retarded. We report on follow-up data of these patients obtained by MRI, in addition to the histopathological, biochemical and clinical investigations. MR images of six non-transplanted patients and seven healthy children served as controls. In the non-transplanted patients, MRI revealed evident delay of myelination in contrast to the two transplanted patients showing fair or evident grey- vs. white matter differentiation on T2-weighted images. The aspartylglucosaminidase (AGA) activity in blood leukocytes reached a heterozygous level. Urinary excretion of aspartylglucosamine and glycoasparagines slowly decreased but remained about a third of the pre-BMT level 5 years after BMT. Storage lysosomes in electron microscopic investigations were not decreased 6 months after BMT, but after 1.5-2 years, rectal mucosa samples showed a decrease in the storage vacuoles of different cells. Three years after BMT, no cells with storage vacuoles were present. Allogeneic BMT slowly normalises the pathological, biochemical and MRI findings in patients with AGU.

Extensive cerebral white matter abnormality without clinical symptoms: a new hereditary condition?

A 30-year-old father and his 2 sons with slight hyperkinesia and mildly dysmorphic features and their close relatives were examined clinically and with computed tomography (CT) and magnetic resonance imaging (MRI). Neurophysiological and biochemical examinations were normal; however, brain MRI of the father and sons revealed extensive cerebral white matter changes. No radiological progression could be detected at a 13-year follow-up examination of the father, and proton magnetic resonance spectroscopy (MRS) of the father at the age of 30 years was normal. MRI findings in the relatives were normal, suggesting an autosomal dominant syndrome due to a new mutation in the father.

Lamotrigine therapy in juvenile neuronal ceroid lipofuscinosis

PURPOSE

To evaluate the effects of lamotrigine (LTG) therapy on epileptic seizures and general well-being in patients with juvenile neuronal ceroid lipofuscinosis (JNCL).

METHODS

LTG was initiated in 28 patients with JNCL. The mean age of the patients at the initiation of LTG was 13.7 years (range, 6.7-28.2 years). LTG was started at a dosage of 0.1-0.5 mg/kg/day and increased every 2 weeks until a maintenance dose of 1.25-15 mg/kg/day was reached. On the basis of the indication for LTG therapy, the patients could be divided into four groups. In the first group, LTG was initiated on an add-on basis; in the second group, LTG was started as the first antiepileptic drug (AED) because of seizures, and in the third group, despite no preceding seizures, because of epileptiform activity in the whole-night polysomnography; in the fourth group, LTG replaced valproate (VPA), which was discontinued because of adverse side effects. The efficacy was assessed after 1 year on LTG. The mean follow-up time was 2.8 years (range, 1.3-5.8).

RESULTS

LTG had a favorable effect in 23 of 28 patients. A decrease in frequency of seizures of > or =50% was observed in 10 and a decrease in severity of seizures in nine of the 22 patients who had preceding seizures. Increases in well-being were found in 18 of 28. During the follow-up, LTG was continued as monotherapy in 13 of 19 patients.

CONCLUSIONS

In light of our experiences, LTG seems to be a valuable drug in JNCL.

A rapid fluorogenic palmitoyl-protein thioesterase assay: pre- and postnatal diagnosis of INCL

A deficiency of palmitoyl-protein thioesterase (PPT) was recently shown to be the primary defect in infantile neuronal ceroid lipofuscinosis (INCL). The available enzyme assays are complicated and impractical for diagnostic use. We have recently developed a new, fluorometric assay for PPT based on the sensitive fluorochrome 4-methylumbelliferone, requiring an overnight incubation to measure PPT. Now we have synthesized an analogue of this substrate which allows PPT determinations in 1 h. This improved PPT assay is simple, sensitive, and robust and will facilitate the definition of the full clinical spectrum associated with a deficiency of PPT. PPT activity was readily detectable in fibroblasts, leukocytes, amniotic fluid cells, chorionic villi, plasma, and cerebrospinal fluid from controls. PPT activity was profoundly deficient in these tissues and fluids from INCL patients. Similarly, a deficiency of PPT activity was demonstrated in patients with the variant juvenile NCL with GROD. These results show the feasibility of rapid pre- and postnatal diagnosis of INCL and its variants.

Melatonin ineffective in neuronal ceroid lipofuscinosis patients with fragmented or normal motor activity rhythms recorded by wrist actigraphy

Melatonin was tested as a sleeping pill in five patients with neuronal ceroid lipofuscinoses. The single-blind, placebo-controlled study consisted of motor activity recordings, sleep logs, and administration of placebo or melatonin (2.5 or 5 mg). Daily motor activity rhythms were measured by wrist actigraphy during four 7-day periods (baseline, placebo, melatonin 2.5 mg, and melatonin 5 mg). The placebo or melatonin was administered in the evenings for 3 weeks, and the recordings were made during the last week of the 3-week treatment. Sleep logs were kept by the caregivers during the recordings. Based on period analyses, the activity recordings were evaluated to display a normal (24-h) or fragmented rhythm. Three patients had normal motor activity patterns during the baseline recordings, and administration of placebo or melatonin did not affect their rest/activity rhythms. Two patients had abnormally fragmented activity rhythms during the baseline periods, and administration of placebo or melatonin did not induce synchronization. According to the actigraphic data, there were no changes in activity rhythms resulting from administration of melatonin. However, based on the observations, three families reported that melatonin slightly improved the sleep quality of the patients. These controversial findings show the difficulties involved in specifying the role of melatonin in modulating sleep. Thus, we conclude that more evidence is required before the significance of melatonin as a sleeping pill is defined.

Delayed classic and protracted phenotypes of compound heterozygous juvenile neuronal ceroid lipofuscinosis

OBJECTIVE

To correlate the phenotypes with the genotypes of 10 Finnish juvenile neuronal ceroid lipofuscinosis (JNCL; late-onset Batten disease) patients who all are compound heterozygotes for the major 1.02-kb deletion in the CLN3 gene.

METHODS

The mutations on the non-1.02-kb deletion chromosomes were screened in 6 patients; in the other 4 patients the mutations were known (one affecting a splice site, two missense mutations, and one deletion of exons 10 through 13). Clinical features were examined, and MRI, MRS, somatosensory evoked magnetic field (SEF), and overnight polysomnography (PSG) studies were performed.

RESULTS

A novel deletion of exons 10 through 13 was found in 6 patients belonging to three families. In the patients carrying the deletions of exons 10 through 13 the clinical course of the disease was fairly similar. Variation was greatest in the time course to blindness. In these patients the mental and motor decline was slower than in classic JNCL, but more severe than in the two patients with missense mutations in exons 11 and 13. MRI showed brain atrophy in 4 patients. One patient had hyperintense periventricular white matter, otherwise brain signal intensities were normal. SEFs were enhanced in patients older than 14 years, whereas in PSG all but the youngest 6-year-old patient showed epileptiform activity in slow-wave sleep.

CONCLUSIONS

JNCL can manifest as at least three different phenotypes: classic, delayed classic, and protracted JNCL with predominantly ocular symptoms. Finnish compound heterozygotes have the delayed classic or the protracted form of JNCL.

Assignment of the muscle-eye-brain disease gene to 1p32-p34 by linkage analysis and homozygosity mapping

Muscle-eye-brain disease (MEB) is an autosomal recessive disease of unknown etiology characterized by severe mental retardation, ocular abnormalities, congenital muscular dystrophy, and a polymicrogyria-pachygyria-type neuronal migration disorder of the brain. A similar combination of muscle and brain involvement is also seen in Walker-Warburg syndrome (WWS) and Fukuyama congenital muscular dystrophy (FCMD). Whereas the gene underlying FCMD has been mapped and cloned, the genetic location of the WWS gene is still unknown. Here we report the assignment of the MEB gene to chromosome 1p32-p34 by linkage analysis and homozygosity mapping in eight families with 12 affected individuals. After a genomewide search for linkage in four affected sib pairs had pinpointed the assignment to 1p, the MEB locus was more precisely assigned to a 9-cM interval flanked by markers D1S200 proximally and D1S211 distally. Multipoint linkage analysis gave a maximum LOD score of 6.17 at locus D1S2677. These findings provide a starting point for the positional cloning of the disease gene, which may play an important role in muscle function and brain development. It also provides an opportunity to test other congenital muscular dystrophy phenotypes, in particular WWS, for linkage to the same locus.

CLN5, a novel gene encoding a putative transmembrane protein mutated in Finnish variant late infantile neuronal ceroid lipofuscinosis

The neuronal ceroid lipofuscinoses (NCLs) represent a group of common recessive inherited neurodegenerative disorders of childhood, with an incidence of 1:12,500 live births. They are characterized by accumulation of autofluorescent lipopigments in various tissues. Several forms of NCLs have been identified, based on age at onset, progression of disease, neurophysiological and histopathological findings and separate genetic loci. All types of NCL cause progressive visual and mental decline, motor disturbance, epilepsy and behavioral changes, and lead to premature death. One of the subtypes, Finnish variant late infantile neuronal ceroid lipofuscinosis (vLINCL; MIM256731) affects children at 4-7 years of age. The first symptom is motor clumsiness, followed by progressive visual failure, mental and motor deterioration and later by myoclonia and seizures. We have previously reported linkage for vLINCL on chromosome 13 (ref. 5) and constructed a long-range physical map over the region. Here, we report the positional cloning of a novel gene, CLN5, underlying this severe neurological disorder. The gene encodes a putative transmembrane protein which shows no homology to previously reported proteins. Sequence analysis of DNA samples from patients with three different haplotypes revealed three mutations; one deletion, one nonsense and one missense mutation, suggesting that mutations in this gene are responsible for vLINCL.

Bright light suppresses melatonin in blind patients with neuronal ceroid-lipofuscinoses

We studied whether light information can reach the pineal glands of clinically blind patients with neuronal ceroid-lipofuscinoses. The suppression of melatonin by light was used as an indicator. Seven patients and seven control subjects were exposed to 3,000-lux light for 60 minutes at the rising phase of the melatonin synthesis. Most patients were not cooperative, and their eyelids were opened by a researcher every 2 minutes for 2 seconds. The control subjects opened and closed their eyes similarly by themselves. Light suppressed melatonin in three of seven control subjects and in all patients. The average postlight levels were 80% (control subjects) and 51% (patients) of the corresponding levels during the dim-light session. Despite degenerated retinas of the blind patients, light can penetrate their visual system to the hypothalamic and pineal levels and regulate neuroendocrine function.

Atypical juvenile neuronal ceroid lipofuscinosis with granular osmiophilic deposit-like inclusions in the autonomic nerve cells of the gut wall

In this 8-year-old boy, who had been exposed to alcohol and oxazepam during pregnancy, visual failure was the first symptom of a neuronal ceroid lipofuscinosis (NCL) disorder, noticed at the age of 5 years. Ophthalmological examinations revealed a cystic type of macular degeneration, which would be more likely to be found in variant late infantile NCL. However, vacuolated lymphocytes were found in peripheral blood films and a diagnosis of the juvenile form of NCL (JNCL) was made. Molecular genetic studies showed the patient to be homozygous for the major mutation of JNCL, a 1.02-kb deletion. In whole-night polysomnography, there was significantly more epileptiform activity than in other JNCL patients under 10 years of age. Using magnetic resonance imaging, the signal intensity of the white matter was increased, especially in the periventricular area. In addition, there were enlarged perivascular spaces in the watershead areas. The corpus callosum was thin. Finally, in the autonomic ganglion cells of the submucosal nerve plexus there were membrane-enclosed homogeneous and granular cytosomes resembling the granular osmiophilic deposits of infantile NCL. However, extraneural cells, including blood capillaries and smooth muscle, showed inclusions with fingerprint and curvilinear profiles. The features of the present case indicated a phenotypic variant of JNCL.

Muscle-eye-brain disease: clinical features, visual evoked potentials and brain imaging in 20 patients

Clinical features, magnetic resonance imaging and visual evoked potentials were analysed and correlated in 20 Finnish patients with muscle-eye-brain disease. Significantly enhanced visual evoked potentials were found in 15 patients (giant in 14 of them). Magnetic resonance images were available in 17 cases. The images of 12 patients with giant visual evoked potentials showed typical brain malformation pachygyria with a nodular cortical surface i.e. cobblestone cortex, midline defect and hypoplastic pons but no significant abnormalities in the grey-white matter. One male had typical structural changes but flat visual evoked potentials. His extreme hydrocephalus with optic nerve compression may explain the findings. No structural changes on magnetic resonance images were found in the remaining four patients; however, in two of them marked alterations in the white matter were found. Three of these patients showed normal and one flat visual evoked potentials. Only one patient with giant visual evoked potentials and typical structural findings on magnetic resonance imaging had changes in a large area in the white matter (several attacks of status epilepticus might have caused the alterations in the white matter). Thus, the combination of giant visual evoked potentials and typical structural changes on magnetic resonance imaging with normal intensities of white matter and deep grey matter seems to be a good marker for patients with muscle-eye-brain disease.

Clinical and magnetic resonance imaging findings in Batten disease: analysis of the major mutation (1.02-kb deletion)

A total of 36 patients with Batten disease (juvenile-onset neuronal ceroid lipofuscinosis), homozygous or heterozygous for the major mutation, a 1.02-kb deletion, in the CLN3 gene, were studied to relate their genotype to their clinical phenotype. The onset of visual failure and epilepsy was highly concordant in both groups. Great inter- and intrafamilial heterogeneity was demonstrated in the development of mental and physical handicap and in magnetic resonance imaging findings among both homozygous and heterozygous patients. The 1.02-kb deletion in homozygous form was always associated with mental and physical handicap, whereas the heterozygous phenotype could be extremely benign without affecting the intellectual level of the patient. Our data suggest that genetic background, modifying genes, and environmental factors all influence the final phenotype of Batten disease.

Aspartylglucosaminuria: radiologic course of the disease with histopathologic correlation

Twelve living patients (aged 19 months to 32 years) with aspartylglucosaminuria were examined by magnetic resonance imaging (MRI), and the magnetic resonance (MR) images of 16 health volunteers (aged 4 to 32 years) were used as controls. One patient was examined twice. Postmortem MRI and histopathologic analysis were done on the brains of four additional adult patients. Signal intensities determined quantitatively on T2-weighted images differed significantly between patients and controls, being higher from the white matter (P < .0002) and lower from the thalami (P < .03) in the patients. The generally increased signal intensity of the white matter was most obvious in the young patients, with many focal areas of very high signal intensity in the subcortical white matter. The subcortical white matter showed a somewhat increased signal intensity even at the age of 32 years. In two of the four postmortem MR images, the distinction between the gray and white matter was still poor. At histopathologic analysis, the basic cortical cytoarchitecture was generally preserved but most neurons contained vacuoles, which were also found in the neurons of the deep gray matter. In two of the four autopsy cases the white matter showed diffuse pallor of myelin staining and some gliosis. Thus aspartylglucosaminuria is primarily a gray-matter disease also affecting white matter by delaying myelination.

Somatosensory evoked magnetic fields from primary sensorimotor cortex in juvenile neuronal ceroid lipofuscinosis

The present study evaluated neurophysiologic function of the primary sensorimotor cortex in juvenile neuronal ceroid lipofuscinosis. A 122-channel magnetometer, which allowed studies of the somatosensory system in millimeter and millisecond precision, was used to record somatosensory evoked magnetic fields to median nerve stimulation from 10 patients and their matched control subjects. In both patients and controls, the somatosensory evoked magnetic fields from primary sensorimotor area typically consisted of N20m, P35m, and P60m deflections. In the patients, N20m was significantly delayed, whereas P35m peaked earlier than in the control subjects. The source strengths for N20m and P35m were greater in the patients than in the controls. Both deflections showed a significant positive correlation with the disease duration: the sources were stronger in the older patients than in the younger ones. P60m deflections were normal or reduced in the patients. The results indicated increased thalamocortical excitability in the sensorimotor cortex in juvenile neuronal ceroid lipofuscinosis.

EEG and evoked potentials in infantile neuronal ceroid-lipofuscinosis

Sixteen children with infantile neuronal ceroid-lipofuscinosis (INCL), age range 0.5 to 5.4 years, were studied using EEG, electroretinograms (ERG), visual evoked potentials (VEP) and somatosensory evoked potentials (SEP). Electroencephalography was the first of these examinations to reveal abnormalities, however the EEG may be normal at the preclinical stage. The first abnormality to appear was an attenuated reaction to passive eye opening and closing which was followed by disturbances in background activity and diminution in amplitude, and by disappearance of sleep spindles. The gradual disappearance of posterior rhythm reactivity and of sleep spindles suggests that thalamic dysfunction progresses with time. EEG inactivity appeared by the age of 3 years. Evoked potentials were normal in the early stages of the disease. SEP showed abnormalities at Stage 2 (1.7 years), while ERG and VEP abnormalities appeared at Stage 3 (by the age of 2.5 years). All neurophysiological reactions examined were abolished by the age of 4 years. Follow-up EEG gives important hints as to the early diagnosis of INCL. Progression of the disease can be followed by evoked potentials which may also be helpful in the differential diagnostics.

[18F]fluorodopa PET shows striatal dopaminergic dysfunction in juvenile neuronal ceroid lipofuscinosis

OBJECTIVES

To investigate whether nigrostriatal dopaminergic hypofunction is related to the extrapyramidal symptoms in patients with juvenile neuronal ceroid lipofuscinosis (JNCL).

METHODS

Nine patients with JNCL and seven healthy controls were studied using [18F]fluorodopa PET.

RESULTS

In the patients with JNCL [18F]fluorodopa uptake (K[i][occ]) in the putamen was 60% of the control mean and the corresponding figure in the caudate nucleus was 79%. There was a weak correlation between putamen K(i)(occ) values and extrapyramidal symptoms of the patients evaluated by the motor part of the unified Parkinson's disease rating scale (r = -0.57, P < 0.05). The overall severity of the disease also displayed a negative correlation with the K(i)(occ) values in the putamen (r = -0.71, P < 0.05).

CONCLUSION

In patients with JNCL there was reduced striatal [18F]fluorodopa uptake, which had a modest correlation with extrapyramidal symptoms. Dysfunction of nigrostriatal dopaminergic neurons is therefore not the only cause of the patients' extrapyramidal symptoms, but degenerative changes in other brain areas are also contributory.

MRI of neuronal ceroid lipofuscinosis. II. Postmortem MRI and histopathological study of the brain in 16 cases of neuronal ceroid lipofuscinosis of juvenile or late infantile type

Postmortem MRI was carried out on the formalin-fixed brains of 14 patients with juvenile (JNCL) and two with late infantile neuronal ceroid lipofuscinosis, one of variant and the other of classical type. Two patients with JNCL had also undergone MRI during life. After MRI, specimens for histopathological analysis were taken from standard areas of the cerebral cortex, deep nuclei and white matter. The signal intensity of the periventricular white matter was usually higher than that of the peripheral white matter, a finding which correlated with the severe periventricular loss of myelin and gliosis observed histologically. The signal intensity was usually lower in the thalamus than in the putamen; in some patients the signal intensity of the thalamus was equal to or even lower than that of the white matter. However, myelin loss, gliosis, the storage process or neuronal loss in the thalamus did not correlate with the MRI findings. Since in one patient with JNCL the ante- and postmortem MRI did not differ basically, it appears probable that the periventricular changes detected in vivo on MRI are due to the severe loss of myelin and gliosis observed in this study. However, changes resulting from the fixation process must be considered, when postmortem and in vivo MRI are correlated.

Variant late infantile neuronal ceroid-lipofuscinosis: pathology and biochemistry

The neuronal ceroid-lipofuscinoses (NCL) are among the most common inherited neurodegenerative disorders of childhood. The genomic defect causing a variant late infantile neuronal ceroid-lipofuscinosis (vLINCL, also called CLN-5 or variant Jansky-Bielschowsky disease) has recently been localized to chromosome 13q22, thus delineating this disease as a separate entity. This particular form of NCL is clinically well defined, but lacks pathomorphological and biochemical description. The present analyses indicate that subunit c of the mitochondrial ATP synthase is the major protein in vLINCL brain storage cytosomes. These cytosomes also contain minor amounts of sphingolipid activator proteins (SAPs). The immunohistological distribution of subunit c and SAPs in the central nervous system (CNS) and visceral tissues closely resembles that of classical LINCL. Thus, despite clinical differences and the fact that various forms of NCL are caused by different genetic defects, variant and classical LINCL as well as juvenile NCL are all characterized by pronounced lysosomal accumulation of the same hydrophobic protein, subunit c of the mitochondrial ATP synthase.

Sumatriptan for migraine attacks in children: a randomized placebo-controlled study. Do children with migraine respond to oral sumatriptan differently from adults?

Oral sumatriptan is an effective acute treatment for migraine in adults, but its efficacy in children is still undetermined. Twenty-three children, aged 8.3 to 16.4 years, took both sumatriptan and placebo in a randomized, double-blind, placebo-controlled, crossover trial. The primary endpoint was a > or = 50% decrease in pain intensity on a 100-mm visual analogue scale at 2 hours. Other endpoints of efficacy were pain intensity difference (PID), showing pain relief at each time point; summed pain intensity differences (SPIDs), estimating overall pain relief; and preference. Two hours after sumatriptan, 7 of 23 reached the primary endpoint, and after placebo, 5 of 23 (difference 9%, 95% CI for difference, -21 to 38%; p = ns). Within 2 hours, the headache disappeared completely in 5 of 23 children after sumatriptan and in 2 of 23 children after placebo (p = ns). Median PIDs were slightly better for sumatriptan between 0.5 and 4 hours (p = ns). Median SPIDs increased almost identically up to 2 hours. Thereafter, median SPIDs for placebo remained practically constant, whereas for sumatriptan, the improvement continued. At 4 hours, the median SPID for sumatriptan was 2.4 times as high as for placebo. However, the maximum differences between median SPIDs at 4 hours (38.5, 95% CI, -75.8 to 57.5; Wilcoxon signed rank test, p = 0.4) or at any other point were not statistically significant. Of the 23 children, 13 preferred sumatriptan and 2 placebo (sign test, p = 0.004). The failure of this and previous controlled studies suggests that the response of children to sumatriptan may be different from adults.

Brain perfusion SPECT abnormalities in neuronal ceroid lipofuscinoses

Brain perfusion was studied with the Tc-99m-HMPAO SPECT method in 19 INCL patients, 21 JNCL patients and 5 patients with Jansky-Bielschowsky variant disease (JBVD). The typical SPECT findings at an early stage of INCL were bilateral anterior frontal, posterior temporoparietal and occipital hypoperfusion, whereas reduction in cerebellar perfusion appeared later. However, perfusion of basal ganglia and thalami, although atrophic on MRI, was usually well preserved up to the terminal stage. All JNCL patients except one had at least one hypoperfused area. Mild hypoperfusion was usually located in the parietal and occipital lobes and cerebellum, whereas more severe hypoperfusion was observed in the temporal lobes. In JNCL, SPECT revealed lesions not detected on CT. All JBVD patients had supra- and infratentorial hypoperfusion, which was usually bilateral. This study shows that although in NCLs brain hypoperfusion can appear prior to structural abnormalities seen on MRI or CT, such abnormalities are not always associated with significant hypoperfusion.

Strategy for mutation detection in CLN3: characterisation of two Finnish mutations

A strategy for detection of mutations in CLN3, the gene for Batten disease or juvenile onset neuronal ceroid lipofuscinosis, has been devised using a technique which detects conformation polymorphisms and direct sequencing of genomic DNA fragments. We define two mutations found uniquely in Finnish patients, one a large deletion (2.8 kb), the other a point mutation affecting the 5'splice donor site of an intron.

Lamotrigine therapy in infantile neuronal ceroid lipofuscinosis (INCL)

Since 1990, altogether 16 INCL patients received lamotrigine (LTG) because of intractable epilepsy. The response to LTG was favorable in 15/16 children. The severity of seizures decreased significantly in 15/16 patients, the frequency of seizures decreased in 14/16, and the effects were maintained. In addition, LTG had a beneficial effect on the well-being of 14/16 children. LTG failed to maintain it's efficacy in monotherapy. No severe side effects were found.