👤 Jennifer Vermilion

CLN3 disease, or Juvenile Neuronal Ceroid Lipofuscinosis (JNCL), is a rare, genetic neurodegenerative condition, typically manifesting in the first decade of life and progressing in severity, with death typically occurring in early adulthood. Despite two decades of natural history research, a clear timeline of CLN3 disease symptom onset and progression remains poorly defined, limiting optimal patient management and therapeutic development. We conducted a literature review and analysed the natural history data to better understand the age of core symptom onset and chronological disease progression. A literature review was undertaken using a pre-defined search strategy focused on CLN3 disease natural history studies, where age at onset for one or more core symptoms was reported in cohorts of ≥ 15 subjects. For each symptom, weighted mean age at onset and weighted standard deviation were calculated, with 95% confidence intervals derived from the weighted standard error. Symptom onset ages were compared using ANOVA. We identified nine natural history studies that met our pre-defined criteria. In total, 423 discrete patients aged between 4 and 39 years were reported. Thirteen core symptoms and a weighted average age at onset and weighted standard deviation were (in years): vision loss (6.1 ± 1.6, This comprehensive summary of available natural history data illustrates mean age at onset of 13 core symptoms of CLN3 disease, and characterises a chronological timeline of disease progression. These results provide much-needed practical, anticipatory guidance to those involved in caring for individuals with CLN3 disease, and serve to highlight the critical importance of collecting globally standardised, quantifiable, longitudinal data for optimising patient management and advancing therapeutic approaches for CLN3 disease. The online version contains supplementary material available at 10.1186/s13023-025-04174-5. Show less

There is currently limited information about sensory and perceptual abilities across the progression of CLN3 disease (Juvenile Neuronal Ceroid Lipofuscinosis; Batten disease), a recessively inherited lysosomal storage disorder and a leading cause of childhood neurodegeneration. Clinical symptoms include vision loss, motor impairments, and cognitive challenges, making it difficult to accurately assess neurocognitive and perceptual abilities. Thus, there is a critical need to identify objective biomarkers that can be used to inform disease progression and track treatment response in this population. This exploratory study investigates longitudinal changes in auditory sensory perceptual processing in a small sample of individuals with genetically confirmed CLN3 disease (N=4; 3 male) compared to a cross-sectional sample of 60 neurotypical (NT) controls using high-density electroencephalography (EEG). We utilized a duration mismatch negativity (MMN) paradigm, identical to what has been used in our previous cross-sectional study. We examined the auditory evoked potentials (AEPs) of the standard tones across three different stimulus onset asynchrony conditions and examined the N1 and P2 components of the AEP. We found age related differences in the amplitudes of the N1 and P2 components in individuals with CLN3 disease relative to NT controls. These amplitude differences were most notable in CLN3 disease when participants were presented with standard tones that had the slowest presentation rate. Specifically, N1 and P2 amplitudes were more negative than NT controls in childhood and adolescence and as CLN3 disease participants aged, the amplitude of the AEPs was greater than controls. Further, a more positive N1 amplitude during the longest stimulus presentation condition was associated with both reduced verbal intelligence and working memory abilities in CLN3 disease participants. Our preliminary findings parallel recently published work in a mouse model of CLN3 disease that showed both sex- and age-dependent disruptions in central auditory processing. Taken together, we demonstrate the utility of auditory EEG measures as a sensitive, objective and translational measure in CLN3 disease that may serve as a potential outcome measure useful in tracking disease progression. Continued work is needed in humans focused on sex-based differences and longitudinal changes of auditory processing in CLN3 disease. Show less

CLN3 disease is a rare inherited neurodegenerative disease that typically starts in childhood. Given the progressive nature of the disease, it likely affects the health-related quality of life (HRQOL) of both the child and the family unit. In this study, we evaluated HRQOL and family function in individuals with CLN3 disease and their families. Data were obtained from longitudinal observational studies on CLN3 disease at the University of Rochester Batten Center. Assessments were completed at variable intervals from 2006 to 2024. Parents completed the PedsQL, which assesses child HRQOL, and the PedsQL FIM, which assess family impact. In a subset of participants, we concurrently administered the Unified Batten Disease Rating Scale, a global assessment of CLN3 disease. Data from 71 participants were included in this study, of which 21 participants had concurrent Unified Batten Disease Rating Scale data. Mean (SD) PedsQL Total (48.2 (19.7)) and PedsQL FIM Total (51.2 [16.5]) scores were low. Worse child HRQOL was associated with physical impairment from more severe CLN3 disease (r Children with CLN3 disease and their families are at high risk of impaired HRQOL and function. This information may provide important information for clinical care and trial design in CLN3 disease. Show less

Over the past 20 years, diagnostic testing for genetic diseases has evolved, leading to variable diagnostic certainty for individuals included in long-term natural history studies. Using genotype and phenotype data from an ongoing natural history study of CLN3 disease, we developed a hierarchical diagnostic confidence scheme with three major classes: Definite, Probable, or Possible CLN3 disease. An additional level, CLN3 Disease PLUS, includes individuals with CLN3 disease plus an additional disorder with a separate etiology that substantially affects the phenotype. Within the Definite and Probable CLN3 disease classes, we further divided individuals into subclasses based on phenotype. After assigning participants to classes, we performed a blinded reclassification to assess the reliability of this scheme. A total of 134 individuals with suspected CLN3 disease were classified: 100 as Definite, 21 as Probable, and 7 as Possible. Six individuals were classified as CLN3-PLUS. Phenotypes included the classical juvenile-onset syndromic phenotype, a "vision loss only" phenotype, and an atypical syndromic phenotype. Some individuals were too young to fully classify phenotype. Test-retest reliability showed 96% agreement. We created a reliable diagnostic confidence scheme for CLN3 disease that has excellent face validity. This scheme has implications for clinical research in CLN3 and other rare genetic neurodegenerative disorders. Show less

To develop a disease-specific staging system for CLN3 disease and to test the hypothesis that salient and discrete clinical features of CLN3 disease may be used to define disease stages by analyzed data from an 18-year-long natural history study. A proposed staging system, the CLN3 Staging System (CLN3SS), was based on salient and clinically meaningful endpoints. The relationships between stage and age, stage and Unified Batten Disease Rating Scale (UBDRS) physical severity score, and stage and UBDRS capability impairment subscale scores were determined. We used Data were analyzed from 322 evaluations in 108 individuals. There were significant differences among the stages based on age and severity scores. For individuals with longitudinal data, no individual reverted to a less severe stage over time. The CLN3SS is a disease-specific staging system that can be used to classify individuals into specific strata based on age and disease severity. The CLN3SS has potential applications in clinical trials for cohort stratification. Show less