Psychiatric symptoms of children and adolescents with juvenile neuronal ceroid lipofuscinosis

Overlap between ophthalmology and psychiatry - A narrative review focused on congenital and inherited conditions

A number of congenital and inherited diseases present with both ocular and psychiatric features. The genetic inheritance and phenotypic variants play a key role in disease severity. Early recognition of the signs and symptoms of those disorders is critical to earlier intervention and improved prognosis. Typically, the associations between these two medical subspecialties of ophthalmology and psychiatry are poorly understood by most practitioners so we hope to provide a narrative review to improve the identification and management of these disorders. We conducted a comprehensive review of the literature detailing the diseases with ophthalmic and psychiatric overlap that were more widely represented in the literature. Herein, we describe the clinical features, pathophysiology, molecular biology, diagnostic tests, and the most recent approaches for the treatment of these diseases. Recent studies have combined technologies for ocular and brain imaging such as optical coherence tomography (OCT) and functional imaging with genetic testing to identify the genetic basis for eye-brain connections. Additional work is needed to further explore these potential biomarkers. Overall, accurate, efficient, widely distributed and non-invasive tests that can help with early recognition of these diseases will improve the management of these patients using a multidisciplinary approach.

Anesthesia outcomes in lysosomal disorders: CLN3 and GM1 gangliosidosis

Natural history studies of pediatric rare neurometabolic diseases are important to understand disease pathophysiology and to inform clinical trial outcome measures. Some data collections require sedation given participants' age and neurocognitive impairment. To evaluate the safety of sedation for research procedures, we reviewed medical records between April 2017 and October 2019 from a natural history study for CLN3 (NCT03307304) and one for GM1 gangliosidosis (NCT00029965). Twenty-two CLN3 individuals underwent 28 anesthetic events (age median 11.0, IQR 8.4-15.3 years). Fifteen GM1 individuals had 19 anesthetic events (9.8, 7.1-14.7). All participants had the American Society of Anesthesiology classification of II (8/47) or III (39/47). Mean sedation durations were 186 (SD = 54; CLN3) and 291 (SD = 33; GM1) min. Individuals with GM1 (6/19, 31%) were more frequently prospectively intubated for sedation (CLN3 3/28, 11%). Minor adverse events associated with sedation occurred in 8/28 (28%, CLN3) and 6/19 (32%, GM1) individuals, frequencies within previously reported ranges. No major adverse clinical outcomes occurred in 47 anesthetic events in pediatric participants with either CLN3 or GM1 gangliosidosis undergoing research procedures. Sedation of pediatric individuals with rare neurometabolic diseases for research procedures is safe and allows for the collection of data integral to furthering their understanding and treatment.

Parental experiences of having a child with CLN3 disease (juvenile Batten disease) and how these experiences relate to family resilience

BACKGROUND

CLN3 disease is a neurodegenerative condition presenting in the first decade of life typically leading to death in the third decade. The earliest symptom is rapidly progressive visual impairment followed by intellectual and motor impairments, epilepsy and behavioural disturbances. There are limited data on how the condition affects the family system or the role of family resilience in paediatric neurodegenerative diseases.

METHODS

Semi-structured interviews were conducted with eight parents (five mothers and three fathers) of five children with CLN3. Interview questions focused on the experience of having a child with CLN3, its impact on the family system as well as the concept of family resilience. Data were analysed via thematic analysis.

RESULTS

The thematic analysis resulted in four main themes. The theme 'recurring losses' included the feeling of losing a healthy child, the child's loss of abilities and loss of relationships. The theme 'disruption to the family system' included that siblings could be 'side-lined', the potential negative impact on romantic relationships and difficulties finding time to oneself. The theme 'Society is not developed for a progressive disease' highlighted the difficulties parents faced with respect to contacts with the health and/or social insurance system. The paediatric health care system was seen as supportive, but the adult health care system was not seen as fit for the purpose. Regarding family resilience, parents felt that the disease forced them to reconsider what was important in life. Several parents described that they learned to value small moments of joy and create deep connections through involvement in family routines and rituals.

CONCLUSIONS

CLN3 places a very significant burden on the family system including parental feelings of loss, impact on family relationships and lack of understanding within the health/social insurance systems. The concept of family resilience may be useful in understanding the experiences of families affected by paediatric neurodegenerative conditions.

Sex bias and omission exists in Batten disease research: Systematic review of the use of animal disease models

Batten disease, also known as the neuronal ceroid lipofuscinoses (NCL), is a group of inherited neurodegenerative disorders mainly affecting children. NCL are characterised by seizures, loss of vision, and progressive motor and cognitive decline, and are the most common form of childhood dementia. At least one type of Batten disease and three types of mouse disease models show sex differences in their severity and progression. Scientific research has a recognised prevalent omission of female animals when using model organisms for basic and preclinical research. Sex bias and omission in research using animal models of Batten disease may affect understanding and treatment development. We conducted a systematic review of research publications since the first identification of NCL genes in 1995, identifying those using animal models. We found that <10 % of these papers considered sex as a biological variable. There was consistent omission of female model organisms in studies. This varied over the period but is improving; one third of papers considered sex as a biological variable in the last decade, and there is a noticeable increase in the last 5 years. The wide-ranging reasons for this published sex bias are discussed, including misunderstanding regarding oestrogen, impact on sample size, and the underrepresentation of female scientists. Their implications for Batten disease and future research are considered. Recommendations going forward support requirements by funders for consideration of sex in all stages of experimental design and implementation, and a role for publishers, families and others with a particular interest in Batten disease.

Drug-induced hyperthermia with rhabdomyolysis in CLN3 disease

CLN3 disease (MIM# 204200), the most prevalent of the neuronal ceroid lipofuscinoses (NCL), is an autosomal recessive disorder with juvenile onset characterized by blindness, epilepsy, dementia, psychiatric manifestations, and motor deterioration. Problems related to behavior, emotions and thought are among the main features. Antidepressant and antipsychotic drugs have been employed with variable results. Neuroleptic malignant syndrome (NMS) has previously been described in two patients with NCL, one with CLN3 disease and one with adult onset NCL of unclear genetic origin. Our aims were to describe the occurrence of drug-induced hyperthermia in pediatric patients with CLN3 disease from West and South Sweden and to delineate the range of associated clinical features. Our study identified four patients presenting with seven episodes of severe drug-induced hyperthermia and either NMS-like or Serotonin syndrome (SS)-like features. Possibly provoking drugs were risperidone, clozapine, olanzapine, haloperidol, quetiapine, and sertraline. The course was atypical, frequently prolonged, associated with rhabdomyolysis and status dystonicus, and resulted in the death of three of the patients. Our study points to a vulnerability to drug-induced hyperthermia in patients with CLN3 disease which we believe could be underreported. Interestingly the proposed pathophysiological mechanisms behind NMS and SS on one hand and CLN3 on the other hand seem to converge in a common mechanism involving dysregulation of the sympathetic nervous system.

Towards Understanding Behaviour and Emotions of Children with CLN3 Disease (Batten Disease): Patterns, Problems and Support for Child and Family

The juvenile variant of Neuronal Ceroid Lipofuscinosis (CLN3 disease/Batten disease) is a rare progressive brain disease in children and young adults, characterized by vision loss, decline in cognitive and motor capacities and epilepsy. Children with CLN3 disease often show disturbed behaviour and emotions. The aim of this study is to gain a better understanding of the behaviour and emotions of children with CLN3 disease and to examine the support that the children and their parents are receiving. A combination of qualitative and quantitative analysis was used to analyse patient files and parent interviews. Using a framework analysis approach a codebook was developed, the sources were coded and the data were analysed. The analysis resulted in overviews of (1) typical behaviour and emotions of children as a consequence of CLN3 disease, (2) the support children with CLN3 disease receive, (3) the support parents of these children receive, and (4) the problems these parents face. For a few children their visual, physical or cognitive deterioration was found to lead to specific emotions and behaviour. The quantitative analysis showed that anxiety was reported for all children. The presented overviews on support contain tacit knowledge of health care professionals that has been made explicit by this study. The overviews may provide a lead to adaptable support-modules for children with CLN3 disease and their parents.

Onset of psychiatric signs and impaired neurocognitive domains in inherited metabolic disorders: A case series

Inherited metabolic disorders (IMDs) can present with psychiatric signs that vary widely from one disease to another. This picture is further complicated by the fact that these features occur at very different illness time points, which may further delay appropriate diagnosis and treatment. In this case series of 62 children and adolescents suffering from IMDs, we clustered psychiatric signs (on the basis of the fifth edition of the Diagnostic and Statistical Manual for Mental Disorders classification) as well as impaired cognitive domains (on the basis of the Research Domain Criteriamatrix) according to their mean age of onset (5.7 ± 4 years). We observed consistent patterns of occurrence across disorders. Externalizing symptoms, sleep problems, and cross-domain self-regulation deficits were found to precede the IMD diagnosis. Repetitive thoughts and behaviors as well as emotional dysregulation were found to occur around the disease onset. Finally, late-onset features included dissociative or eating disorders, together with impaired emotion knowledge. Clinicians should specifically look for the co-occurrence of age-specific atypical signs, such as treatment resistance or worsening with psychotropic medication in the earliest stages and symptom fluctuation, confusion, catatonia, or isolated visual hallucinations. We believe that the combined characterizations of psychiatric signs and impaired neurocognitive domains may enable the earliest detection of IMDs and the appropriate care of these particular manifestations.

KEY POINTS

Psychiatric signs are common in inherited metabolic disorders (IMDs) and may occur in the same age-range as other clinical manifestations.Three clusters of psychiatric signs and two clusters of neurocognitive domains can be defined according to their mean age of onset.Warning signs to be used in liaison psychiatry should include age-specific cognitive impairments.

Inherited disorders of lysosomal membrane transporters

Disorders caused by defects in lysosomal membrane transporters form a distinct subgroup of lysosomal storage disorders (LSDs). To date, defects in only 10 lysosomal membrane transporters have been associated with inherited disorders. The clinical presentations of these diseases resemble the phenotypes of other LSDs; they are heterogeneous and often present in children with neurodegenerative manifestations. However, for pathomechanistic and therapeutic studies, lysosomal membrane transport defects should be distinguished from LSDs caused by defective hydrolytic enzymes. The involved proteins differ in function, localization, and lysosomal targeting, and the diseases themselves differ in their stored material and therapeutic approaches. We provide an overview of the small group of disorders of lysosomal membrane transporters, emphasizing discovery, pathomechanism, clinical features, diagnostic methods and therapeutic aspects. We discuss common aspects of lysosomal membrane transporter defects that can provide the basis for preclinical research into these disorders.

Novel Mutations in CLN5 of Chinese Patients With Neuronal Ceroid Lipofuscinosis

Neuronal ceroid lipofuscinosis is a hereditary disease, and ceroid-lipofuscinosis neuronal protein 5 (CLN5) has been proved to be associated with neuronal ceroid lipofuscinosis. Here we report 3 patients from 2 families diagnosed with CLN5 neuronal ceroid lipofuscinosis. Whole genome sequencing of DNAs from 3 patients and their families revealed 3 novel homozygous mutations, including 1 deletion CLN5.c718 719delAT and 2 missense mutations c.1082T>C and c.623G>A. We reviewed 278 papers about neuronal ceroid lipofuscinosis resulting from CLN5 mutations and compared Chinese cases with 27 European and American cases. The overall age of onset of European and American patients occur mainly at 3 to 6 years (66%, 18/27), 100% (27/27) of patients had psychomotor regression, 99% (26/27) patients presented vision decline, and 70% (19/27) of patients suffered seizures. In China, the age of onset in 3 patients was 5 years, but for 1 patient it was at 17 months. Four Chinese patients presented psychomotor deterioration and seizures; only 1 had visual problems.

Paroxysmal sympathetic hyperactivity in Juvenile neuronal ceroid lipofuscinosis (Batten disease)

Paroxysmal sympathetic hyperactivity (PSH) is a clinical syndrome of agitation and involuntary motor activity that particularly occurs in patients with severe acquired brain injury. The aim of the present study is to substantiate the assertion that paroxysmal non-epileptic attacks resembling PSH also occur in patients with Juvenile Neuronal Ceroid Lipofuscinosis (JNCL, Batten disease), which is the most common neurodegenerative disease in children. The paper describes a case series of five patients with JNCL which during a period of fifteen years have been followed clinically and by consecutive investigations of the autonomic nervous system using heart rate variability (HRV) investigations. Following adolescence a significant autonomic imbalance with very low parasympathetic activity and an unchanged high sympathetic excitatory activity was documented. In addition, episodes of anxiety and agitation combined with involuntary movements were reported. Beyond the frightened facial expression and involuntary increased motor activity, excessive sweating, increased body temperature, high heart and respiratory rates were reported, and typically, the episodes occurred to stimuli that were either non-nociceptive or only minimally nociceptive. Thus, from a clinical point of view the non-epileptic paroxysmal condition with anxious behavior, agitation and motor hyperactivity seen in patients with JNCL fits to the clinical description of PSH which normally occurs following acutely acquired brain injury, and as the neuropathological basis in JNCL for development of PSH is similar to what is seen in patients with traumatic brain injuries, it seems reasonable to propose that PSH also occurs following adolescence in patients with JNCL.

Inborn errors of metabolism associated with psychosis: literature review and case-control study using exome data from 5090 adult individuals

A literature review was conducted, using the computerized "Online Mendelian Inheritance in Man" (OMIM) and PubMed, to identify inborn errors of metabolism (IEM) in which psychosis may be a predominant feature or the initial presenting symptom. Different combinations of the following keywords were searched using OMIM: "psychosis", "schizophrenia", or "hallucinations" and "metabolic", "inborn error of metabolism", "inborn errors of metabolism", "biochemical genetics", or "metabolic genetics". The OMIM search generated 126 OMIM entries, 40 of which were well known IEM. After removing IEM lacking evidence in PubMed for an association with psychosis, 29 OMIM entries were identified. Several of these IEM are treatable. They involve different small organelles (lysosomes, peroxisomes, mitochondria), iron or copper accumulation, as well as defects in other met-abolic pathways (e.g., defects leading to hyperammonemia or homocystinemia). A clinical checklist summarizing the key features of these conditions and a guide to clinical approach are provided. The genes corresponding to each of these con-ditions were identified. Whole exome data from 2545 adult cases with schizophrenia and 2545 unrelated controls, accessed via the Database of Genotypes and Phenotypes (dbGaP), were analyzed for rare functional variants in these genes. The odds ratio of having a rare functional variant in cases versus controls was calculated for each gene. Eight genes are significantly associated with schizophrenia (p < 0.05, OR >1) using an unselected group of adult patients with schizophrenia. Increased awareness of clinical clues for these IEM will optimize referrals and timely metabolic interventions.

Defective synaptic transmission causes disease signs in a mouse model of juvenile neuronal ceroid lipofuscinosis

Juvenile neuronal ceroid lipofuscinosis (JNCL or Batten disease) caused by mutations in the CLN3 gene is the most prevalent inherited neurodegenerative disease in childhood resulting in widespread central nervous system dysfunction and premature death. The consequences of CLN3 mutation on the progression of the disease, on neuronal transmission, and on central nervous network dysfunction are poorly understood. We used Cln3 knockout (Cln3^Δex1-6) mice and found increased anxiety-related behavior and impaired aversive learning as well as markedly affected motor function including disordered coordination. Patch-clamp and loose-patch recordings revealed severely affected inhibitory and excitatory synaptic transmission in the amygdala, hippocampus, and cerebellar networks. Changes in presynaptic release properties may result from dysfunction of CLN3 protein. Furthermore, loss of calbindin, neuropeptide Y, parvalbumin, and GAD65-positive interneurons in central networks collectively support the hypothesis that degeneration of GABAergic interneurons may be the cause of supraspinal GABAergic disinhibition.

The value of metaphorical reasoning in bioethics: An empirical-ethical study

Background:

Metaphors are often used within the context of ethics and healthcare but have hardly been explored in relation to moral reasoning.

Objective:

To describe a central set of metaphors in one case and to explore their contribution to moral reasoning.

Method:

Semi-structured interviews were conducted with 16 parents of a child suffering from the neurodegenerative disease CLN3. The interviews were recorded, transcribed, and metaphors were analyzed. The researchers wrote memos and discussed about their analyses until they reached consensus.

Ethical considerations:

Participants gave oral and written consent and their confidentiality and anonymity were respected.

Findings:

A central set of metaphors referred to the semantic field of the hands and arms and consisted of two central metaphors that existed in a dialectical relationship: grasping versus letting go. Participants used these metaphors to describe their child’s experiences, who had to “let go” of abilities, while “clinging” to structures and the relationship with their parent(s). They also used it to describe their own experiences: participants tried to “grab” the good moments with their child and had to “let go” of their child when (s)he approached death. Participants, in addition, “held” onto caring for their child while being confronted with the necessity to “let go” of this care, leaving it to professional caregivers.

Discussion:

The ethical analysis of the findings shows that thinking in terms of the dialectical relationship between “grasping” and “letting go” helps professional caregivers to critically think about images of good care for children with CLN3. It also helps them to bear witness to the vulnerable, dependent, and embodied nature of the moral self of children with CLN3 and their parents.

Conclusion:

Metaphorical reasoning may support the inclusion of marginalized perspectives in moral reasoning. Future studies should further explore the contribution of metaphorical reasoning to moral reasoning in other cases.

Juvenile neuronal ceroid lipofuscinosis (Batten disease): current insights

The present review is focused on juvenile neuronal ceroid lipofuscinosis (JNCL; Batten disease) due to a mutation in CLN3. Functional vision impairment occurring around 5-6 years of age is the first symptom in more than 80% of patients. Approximately 2 years later (though sometimes simultaneously), obvious signs of cognitive impairment appear. Behavior problems can occur in advance, especially in boys. These include anxious and depressed mood, aggressive behavior, and hallucinations, and even psychotic symptoms. Following the teens, severe dementia is present, including loss of memory, attention, and general reasoning abilities, as well as loss of independent adaptive skills such as mobility, feeding, and communicating. Sleep abnormalities, such as settling problems, nocturnal awakenings, and nightmares, are reported in more than half of patients. The vast majority, if not all, patients develop seizures, starting at approximately 10 years of age. Generalized tonic-clonic seizure occurs as the only type of seizure in approximately half of patients, and in combination with partial seizures in a third of patients. There seems to be no difference in seizure severity according to sex or genotype, and there is great variation in seizure activity among patients. Soon after diagnosis, patients begin to have slight ataxic symptoms, and at adolescence extrapyramidal symptoms (rigidity, bradykinesia, slow steps with flexion in hips and knees) occur with increasing frequency. Chewing and swallowing difficulties emerge as well, and food intake is hampered in the late teens. Disabling periodically involuntary movements may occur as well. A progressive cardiac involvement with repolarization disturbances, ventricular hypertrophy, and sinus-node dysfunction, ultimately leading to severe bradycardia and/or other conduction abnormalities, starts in the mid-teens. Patients are usually bedridden at 20 years of age, and death usually occurs in the third decade of life.

Mice heterozygous for cathepsin D deficiency exhibit mania-related behavior and stress-induced depression

Mutations in cathepsin D (CTSD), an aspartic protease in the endosomal-lysosomal system, underlie congenital neuronal ceroid-lipofuscinosis (cNCL, also known as CLN10), a devastating neurodegenerative disease. CLN10 patients die within the first few days of life, and in the few patients who live into adulthood psychopathological symptoms have not been reported. Extensive neuropathology and altered neurotransmission have been reported in CTSD-deficient mice; however signs of neuropsychiatric behavior in these mice are not well characterized due to the severe movement disorder and premature death of the animal. In the present study, we show that heterozygous CTSD-deficient (CTSD HET) mice display an overall behavioral profile that is similar to human mania, including hyperlocomotion, d-amphetamine-induced hyperactivity, sleep-disturbance, and reduced anxiety-like behavior. However, under stressful conditions CTSD HET mice manifest depressive-like behavior, including anhedonia, behavioral despair, and enhanced learned helplessness. Chronic administration of lithium chloride or valproic acid, two clinically effective mood stabilizers, reverses the majority of these behavioral abnormalities. In addition, CTSD HET mice display stress-induced hypersecretion of corticosterone. These findings suggest an important role for CTSD in the regulation of mood stabilization.

Neuronopathic lysosomal storage diseases: clinical and pathologic findings

BACKGROUND

The lysosomal-autophagocytic system diseases (LASDs) affect multiple body systems including the central nervous system (CNS). The progressive CNS pathology has its onset at different ages, leading to neurodegeneration and early death.

METHODS

Literature review provided insight into the current clinical neurological findings, phenotypic spectrum, and pathogenic mechanisms of LASDs with primary neurological involvement.

CONCLUSIONS

CNS signs and symptoms are variable and related to the disease-specific underlying pathogenesis. LAS dysfunction leads to diverse global cellular consequences in the CNS ranging from specific axonal and dendritic abnormalities to neuronal death. Pathogenic mechanisms for disease progression vary from impaired autophagy, massive storage, regional involvement, to end-stage inflammation. Some of these features are also found in adult neurodegenerative disorders, for example, Parkinson's and Alzheimer's diseases. Lack of effective therapies is a significant unmet medical need.

Neurobehavioral features and natural history of juvenile neuronal ceroid lipofuscinosis (Batten disease)

Juvenile neuronal ceroid lipofuscinosis is a childhood-onset neurodegenerative disease with prominent symptoms comprising a pediatric dementia syndrome: intellectual decline, mood and behavioral impairments, and loss of adaptive skills. We review the history of neurobehavioral features in juvenile neuronal ceroid lipofuscinosis and the work of the University of Rochester Batten Center to characterize the extent and progression of neurobehavioral symptoms over the disease course, and discuss the relevance of neurobehavioral studies as an aid to understanding the clinical phenotype of juvenile Batten disease and potential targets for intervention.

The neuropsychiatry of inborn errors of metabolism

A number of metabolic disorders that affect the central nervous system can present in childhood, adolescence or adulthood as a phenocopy of a major psychiatric syndrome such as psychosis, depression, anxiety or mania. An understanding and awareness of secondary syndromes in metabolic disorders is of great importance as it can lead to the early diagnosis of such disorders. Many of these metabolic disorders are progressive and may have illness-modifying treatments available. Earlier diagnosis may prevent or delay damage to the central nervous system and allow for the institution of appropriate treatment and family and genetic counselling. Metabolic disorders appear to result in neuropsychiatric illness either through disruption of late neurodevelopmental processes (metachromatic leukodystrophy, adrenoleukodystrophy, GM2 gangliosidosis, Niemann-Pick type C, cerebrotendinous xanthomatosis, neuronal ceroid lipofuscinosis, and alpha mannosidosis) or via chronic or acute disruption of excitatory/inhibitory or monoaminergic neurotransmitter systems (acute intermittent porphyria, maple syrup urine disease, urea cycle disorders, phenylketonuria and disorders of homocysteine metabolism). In this manuscript we review the evidence for neuropsychiatric illness in major metabolic disorders and discuss the possible models for how these disorders result in psychiatric symptoms. Treatment considerations are discussed, including treatment resistance, the increased propensity for side-effects and the possibility of some treatments worsening the underlying disorder.

Do females with juvenile ceroid lipofuscinosis (Batten disease) have a more severe disease course? The Danish experience

BACKGROUND

Juvenile neuronal ceroid lipofuscinosis (JNCL; Batten disease) is characterized by progressive visual failure starting at 4-7 years of age, followed by seizures, dementia as well as a progressive decline in motor function. The patients are typically bedridden in the late teens and death usually occurs in the third decade of life. It has been suggested, that females may have a more precipitous decline than do males.

OBJECTIVE

To compare sex differences in loss of skills and age at death in an unselected population of Danish Adolescents with Batten disease.

METHOD

Review of hospital records of all 35 Danish patients with JNCL born in the period 1971-2003. The records contain a continuously maintained history of the clinical course and first moments for different events, thus eliminating recall bias.

RESULTS

We found that females with JNCL experienced a later age at diagnosis, but showed an earlier loss of independent functions, and died at an earlier age.

CONCLUSION

Females with JNCL have a more precipitous decline than males, and die at an earlier age. Further studies are needed in order to provide possible explanations for this difference.

Juvenile neuronal ceroid lipofuscinosis and education

Juvenile neuronal ceroid lipofuscinosis (JNCL) is characterized by severe visual impairment with onset around age 4-8 years, and a developmental course that includes blindness, epilepsy, speech problems, dementia, motor coordination problems, and emotional reactions. There is presently no cure and the disease leads to premature death. There have been few studies of non-medical intervention for individuals with JNCL, probably because of the negative prognosis. The present chapter discusses the education of children and adolescents with JNCL on the basis of current knowledge about the variation in perceptual, cognitive and language abilities through the course of the disease, and the possibilities that exist for supporting coping and learning within and outside the classroom. Adapted and special needs education may contribute significantly to improved learning conditions, better maintenance of skills and less frustration for individuals with JNCL. This article is part of a Special Issue entitled: The Neuronal Ceroid Lipofuscinoses or Batten Disease.

Large-scale phenotyping of an accurate genetic mouse model of JNCL identifies novel early pathology outside the central nervous system

Cln3^Δex7/8 mice harbor the most common genetic defect causing juvenile neuronal ceroid lipofuscinosis (JNCL), an autosomal recessive disease involving seizures, visual, motor and cognitive decline, and premature death. Here, to more thoroughly investigate the manifestations of the common JNCL mutation, we performed a broad phenotyping study of Cln3^Δex7/8 mice. Homozygous Cln3^Δex7/8 mice, congenic on a C57BL/6N background, displayed subtle deficits in sensory and motor tasks at 10–14 weeks of age. Homozygous Cln3^Δex7/8 mice also displayed electroretinographic changes reflecting cone function deficits past 5 months of age and a progressive decline of retinal post-receptoral function. Metabolic analysis revealed increases in rectal body temperature and minimum oxygen consumption in 12–13 week old homozygous Cln3^Δex7/8mice, which were also seen to a lesser extent in heterozygous Cln3^Δex7/8 mice. Heart weight was slightly increased at 20 weeks of age, but no significant differences were observed in cardiac function in young adults. In a comprehensive blood analysis at 15–16 weeks of age, serum ferritin concentrations, mean corpuscular volume of red blood cells (MCV), and reticulocyte counts were reproducibly increased in homozygous Cln3^Δex7/8 mice, and male homozygotes had a relative T-cell deficiency, suggesting alterations in hematopoiesis. Finally, consistent with findings in JNCL patients, vacuolated peripheral blood lymphocytes were observed in homozygous Cln3^Δex7/8 neonates, and to a greater extent in older animals. Early onset, severe vacuolation in clear cells of the epididymis of male homozygous Cln3^Δex7/8 mice was also observed. These data highlight additional organ systems in which to study CLN3 function, and early phenotypes have been established in homozygous Cln3^Δex7/8 mice that merit further study for JNCL biomarker development.

Females experience a more severe disease course in Batten disease

Juvenile neuronal ceroid lipofuscinosis (JNCL; CLN3 disease; Batten disease) is an autosomal recessive neurodegenerative disease of childhood. Symptoms typically present at school age with vision loss followed by progressive cognitive decline, motor dysfunction, seizures, and behavior problems. Studies on sex differences in JNCL have yielded mixed results, but parent anecdotes suggest that females experience a more precipitous disease course. Therefore, we sought to determine if sex-based differences exist in JNCL. We used data from the Unified Batten Disease Rating Scale (UBDRS), the Batten Disease Support and Research Association (BDSRA) database, and the PedsQL quality of life (QoL) survey to evaluate sex-based differences in functional independence and time from symptom onset to death. On average, females had JNCL symptom onset one year later and death one year earlier than did males. Despite a later age at onset, females had lower functional capability, earlier loss of independent function, and lower physical QoL. Future research in sex differences in JNCL may help to further understand the biological mechanisms underpinning the disease course and may point to targeted therapies.

Juvenile neuronal ceroid-lipofuscinosis: clinical and molecular investigation in a large family in Brazil

OBJECTIVE

Juvenile Neuronal Ceroid-Lipofuscinosis (JNCL, CLN 3, Batten Disease) (OMIM #204200) belongs to the most common group of neurodegenerative disorders of childhood. We report the clinical data and molecular analysis of a large Brazilian family.

METHOD

Family composed of two consanguineous couples and thirty-two children. Clinical data of ten JNCL patients and molecular analyses on 13 participants were obtained.

RESULTS

The large 1.02 kb deletion was detected. The most severe phenotype, with autistic behavior, tics and parkinsonism was seen in a 12-year-old female and a milder phenotype in a 14-year-old male. Nyctalopia was the first symptom in one deceased child. The visual loss of six patients has been first observed in the school and not at home.

CONCLUSION

The report highlights the phenotypical intrafamily variation in 10 affected children of this family. The molecular investigation of this large family in our metabolic center turned possible the diagnosis, right approach and genetic counseling.

[Juvenile neuronal ceroid lipofuscinosis. Ophthalmologic findings and differential diagnosis]

Neuronal ceroid lipofuscinoses (NCL) are a heterogeneous group of neurodegenerative diseases with mostly autosomal recessive inheritance whose common feature is the intralysosomal accumulation of ceroid lipofuscin. With varying manifestation ages the diseases result in cognitive and motor deterioration, epilepsy, diffuse retinal degeneration, and eventually death. Juvenile ceroid lipofuscinosis (JNCL, CLN3, Batten disease) has the distinctive feature that the ophthalmologic symptoms precede the neurologic symptoms by several years, and thus the ophthalmologist plays a central role in early diagnosis. Important clinical signs of JNCL include bull's eye maculopathy, severely reduced Ganzfeld ERG already at initial presentation, and unusually rapid progression of the functional decline. If JNCL is clinically suspected the diagnosis can be made by means of a standard blood smear and confirmed by genetic detection of the mutation. Although causal therapeutic options are currently only in the developmental stage, early diagnosis by the ophthalmologist is of utmost importance to allow for medical and educational support of the affected child and for adequate counseling of the parents.

Psychiatric and behavioral manifestations of lysosomal storage disorders

The different lysosomal storage disorders (LSDs) manifest with a wide spectrum of clinical presentations. Most of these disorders are typically diagnosed early in life, due to the severity of the associated phenotypes. However, it is important to appreciate that some of the LSDs present later in adolescence or adulthood. The diverse findings triggering the initial diagnosis, as well as the range of manifestations arising later during the disease course, contribute to the complexity of these issues. Clinical presentations occurring at a more advanced age, especially psychiatric and behavioral manifestations, can be overlooked or misdiagnosed. This review describes different psychiatric and behavioral manifestations encountered in individuals with LSDs, including psychosis, schizophrenia, mood disorders, aggressiveness, early-onset dementia, and conduct disorder. Twelve different disorders are presented, including descriptions of their associated biochemical abnormalities, clinical presentations, pathology, epidemiology, and genetics. In addition, discussions of neurocognitive, behavioral, and psychiatric findings are outlined for each disorder. A greater awareness of these features may help to reduce missed diagnoses, to avoid unnecessary, invasive and expensive testing, and to facilitate an earlier detection of these rare disorders. Earlier diagnosis can enable the implementation of appropriate interventions and improve genetic counseling.

CLN5 mutations are frequent in juvenile and late-onset non-Finnish patients with NCL

OBJECTIVES

To explore a potential expansion of the phenotypic and genotypic characteristics of Finnish variant late-infantile neuronal ceroid lipofuscinosis (NCL), we screened a collection of 47 patients with clinically diagnosed NCL in whom no molecular diagnosis had been made.

METHODS

We used PCR amplification of genomic DNA, followed by fluorescent-labeled dideoxy-nucleotide chain termination sequencing and multiplex ligation-dependent probe amplification, to screen our cohort of patients for mutations in CLN5. We collected ethnic background, clinical, and pathologic information, as available, to clarify the breadth of CLN5 disease expression and to explore possible genotype-phenotype correlations.

RESULTS

We identified 10 patients with pathogenic CLN5 mutations, including 11 mutations not previously described: 4 missense, 5 out-of-frame insertion/deletion mutations, and 2 large intragenic deletions. We also documented 3 previously reported CLN5 mutations. The age at disease onset in this cohort is predominantly juvenile rather than late infantile. Importantly, we have identified 2 adult-onset patients who share a common pathogenic allele. The majority of patients presented with motor and visual impairments and not seizures. In those patients with available longitudinal data, most had progressed to global neurodevelopmental and visual failure with seizures within 1 to 4 years.

CONCLUSIONS

Our study suggests that CLN5 mutations 1) are more common in patients with neuronal ceroid lipofuscinosis (NCL) than previously reported, 2) are found in non-Finnish NCL patients of broad ethnic diversity, and 3) can be identified in NCL patients with disease onset in adult and juvenile epochs. CLN5 genetic testing is warranted in a wider population with clinical and pathologic features suggestive of an NCL disorder.

Juvenile neuronal ceroid lipofuscinosis (JNCL) and the eye

Juvenile neuronal ceroid lipofuscinoses, or Batten disease, is the most common type of NCL in the United States and Europe. This devastating disorder presents with vision failure and progresses to include seizures, motor dysfunction, and dementia. Death usually occurs in the third decade, but some patients die before age twenty. Though the mechanism of visual failure remains poorly understood, recent advances in molecular genetics have improved diagnostic testing and suggested possible therapeutic strategies. The ophthalmologist plays a crucial role in both early diagnosis and documentation of progression of juvenile neuronal ceroid lipofuscinoses. We update Batten disease research, particularly as it relates to the eye, and present various theories on the pathophysiology of retinal degeneration.

Neuropsychological symptoms of juvenile-onset batten disease: experiences from 2 studies

Juvenile neuronal ceroid lipofuscinosis (Batten disease) is a progressive and fatal autosomal-recessive inherited lysosomal storage disorder of childhood. Core symptoms include vision loss, seizures, and mental and motor decline. This article presents data from 2 studies of neuropsychological function in juvenile neuronal ceroid lipofuscinosis. In the first cross-sectional pilot study, 15 children with genetic or clinicopathologic confirmation of juvenile neuronal ceroid lipofuscinosis completed a brief test of attention (mean age = 14.3 +/- 2.9 years, range = 8.75-18.74 years; 7 males, 8 females). Average attention performances were significantly below age-expected normative data. A second longitudinal study was then initiated to study neuropsychological function in greater depth, including change in function over time. The authors have enrolled 18 children to date (mean age = 12.88 +/- 3.59 years, range = 6.26-18.65; 11 males, 7 females). Of these, 5 children have completed a second (annual) re-evaluation. Results thus far indicate significant impairment in domains of auditory attention, memory, estimated verbal intellectual function, and verbal fluency. Neuropsychological impairment was significantly correlated with disease duration and with motor function as assessed by a disease-specific clinical neurologic rating scale. There was no significant difference between males and females in neuropsychological test performance. Neuropsychological function was worse among children with a positive seizure history. Juvenile neuronal ceroid lipofuscinosis-affected children exhibited significant and pervasive impairments on tests of auditory attention, verbal memory and repetition, verbal fluency, and an estimate of verbal intellectual ability. Preliminary follow-up data from an annual reassessment showed progressive declines in cognitive function, in particular on a task of working memory. Neuropsychological deficits are pervasive and progressive. Future research will focus on clarifying the relationship among disease duration, motor function, and neuropsychological performances, including the relative sensitivity of neuropsychological testing at different stages of motor impairment or disease duration.

Diagnosis of the neuronal ceroid lipofuscinoses: An update

For the majority of families affected by one of the neuronal ceroid lipofuscinoses (NCLs), a biochemical and/or genetic diagnosis can be achieved. In an individual case this information not only increases understanding of the condition but also may influence treatment choices and options. The presenting clinical features prompt initial investigation and also guide clinical care. The clinical labels "infantile NCL", "late infantile NCL" and "juvenile NCL", therefore remain useful in practice. In unusual or atypical cases ultra-structural analysis of white blood cells or other tissue samples enables planning and prioritisation of biochemical and genetic tests. This review describes current methods available to achieve clinical, pathological, biochemical and genetic diagnosis in children presenting with symptoms suggestive of one of the NCLs.

Standardized assessment of behavior and adaptive living skills in juvenile neuronal ceroid lipofuscinosis

We obtained information about the behavioral, psychiatric, and functional status of 26 children (13 males, 13 females) with juvenile neuronal ceroid lipofuscinosis (JNCL; mean age 12y 3mo [SD 3y 4mo]; range 6y 9mo to 18y 8mo). Twenty-five children had visual impairment and 18 were known to have a positive seizure history before enrollment. Parents completed the Child Behavior Checklist, Scales of Independent Behavior - Revised, and a structured interview to assess obsessive-compulsive symptoms. Participants exhibited a broad range of behavioral and psychiatric problems, rated as occurring frequently and/or as severe in more than half of the sample. Males and females did not differ with regard to the number of behavioral and psychiatric problems. Children were also limited in their ability to perform activities of daily living, including self-care, hygiene, socialization, and other age-appropriate tasks. Results provide a quantitative baseline for behavioral and psychiatric problems and functional level in JNCL, against which further decline can be measured. Longitudinal assessment of behavioral and psychiatric symptoms and functional abilities is continuing and will provide much-needed data on the natural history of JNCL.