Multifaceted and Age-Dependent Phenotypes Associated With Biallelic PNPLA6 Gene Variants: Eight Novel Cases and Review of the Literature

A wide spectrum of neurodegenerative diseases has been associated with pathogenic variants in the PNPLA6 (patatin-like phospholipase domain-containing protein 6) gene, including spastic paraplegia type 39, Gordon—Holmes, Boucher—Neuhauser, Oliver—Mc Farlane, and Laurence—Moon syndromes. These syndromes present variable and overlapping clinical symptoms, encompassing cerebellar ataxia, hypogonadotropic hypogonadism, chorioretinal dystrophy, spastic paraplegia, muscle wasting, peripheral neuropathy, and cognitive impairment. In the present study, we performed a wide genetic screening in 292 patients presenting with ataxia or spastic paraplegia using a probe-based customized gene panel, covering >200 genes associated with spinocerebellar diseases. We identified six novel and four recurrent PNPLA6 gene variants in eight patients (2.7%). Six patients presented an infantile or juvenile onset (age <18), and two patients had an adult onset. Cerebellar ataxia was observed in seven patients and spastic paraplegia in one patient. Progression of cerebellar symptoms was slow in all patients, who retained ambulation even after a mean disease duration of 15 years. Brain MRI showed cerebellar atrophy in 6/8 patients, more pronounced in superior and dorsal vermis lobules (I to VII). Additional clinical features included hypogonadotropic hypogonadism (5/8), growth hormone deficiency (2/8), peripheral axonal neuropathy (4/8), cognitive impairment (3/8), chorioretinal dystrophy (2/8), and bilateral vestibular areflexia with a reduced visual vestibule-ocular reflex (1/8). In accordance with previous studies, chorioretinal dystrophy was the most frequent presenting symptom in early onset patients, hypogonadotropic hypogonadism in juvenile onset cases, and cerebellar ataxia in adult patients. One patient had an initial clinical presentation compatible with Cerebellar Ataxia with Neuropathy and Vestibular Areflexia Syndrome (CANVAS), but no pathological expansions in the RFC1 gene. In conclusion, patients with PNPLA6 variants present a variable age of onset spanning from infancy to adulthood, and each clinical symptom has an age-dependent manifestation thus requiring a multi-systemic diagnostic approach. The description of patients presenting very late-onset cerebellar ataxia suggests that PNPLA6 genetic screening should also be considered in the diagnostic workout of adult cerebellar ataxia.

A Novel Coq8a Mutation in a Case with Juvenile Onset Coq10d4: Case Report and Literature Review

Primary coenzyme Q10 deficiency-4 (COQ10D4) is an autosomal recessive disorder characterized by childhood-onset of cerebellar ataxia and exercise intolerance. Molecular pathology responsible for clinical findings is mitochondrial respiratory chain dysfunction. The main clinical manifestation involves early onset exercise intolerance, progressive cerebellar ataxia and movement disorders. Some affected individuals develop seizures and have mild mental impairment, indicating variable severity. COQ8A gene mutations are responsible for this disease. Here we present a patient with tremor and cerebellar atrophy in which we detected a new mutation in the COQ8A gene. The patient's clinical findings were compatible with juvenile onset COQ10D4. Therefore, we reviewed the clinical, laboratory and genetic findings of 11 juvenile-onset COQ10D4 patients reported to date, as well as the patient's presentation.

Dysregulation of complement factor H in juvenile-onset systemic lupus erythematosus patients

Objectives: This study aims to evaluate the expression pattern of factor H in peripheral blood and the frequency of factor H autoantibodies in plasma of juvenile-onset systemic lupus erythematosus (jSLE) patients compared to healthy controls. Patients and methods: Between March 2019 and October 2019, a total of 30 healthy individuals (3 males, 27 females; mean age: 26±7.4 years; range, 18 to 40 years) and 65 jSLE patients (age of onset ≤16 years) (2 males, 63 females; mean age: 23.4±7 years; range, 15 to 38 years) were included. Factor H expression pattern was examined in blood of all subjects using quantitative real-time polymerase chain reaction and the frequency of factor H autoantibodies was estimated in plasma using enzyme-linked immunosorbent assay. Results: Factor H expression was significantly downregulated in jSLE patients compared to healthy controls (p<0.01). A significant underexpression of factor H was observed in jSLE patients with nephritis compared to those without nephritis (p<0.03), while there was no association of factor H expression levels with any of the other clinical and serological features, disease activity or disease damage index of patients. Only 5% of jSLE patients were positive for factor H autoantibodies without any correlations with the clinical data or disease activity of patients. Conclusion: Our study results suggest that factor H expression can be dysregulated in jSLE patients.

Risk factors for progression of juvenile-onset non-radiographic axial spondyloarthritis to juvenile-onset ankylosing spondylitis: a nested case–control study

ObjectiveTo evaluate the clinical characteristics of juvenile-onset non-radiographic axial spondyloarthritis (nr-axSpA) and to investigate risk factors associated with progression to juvenile-onset ankylosing spondylitis (JoAS).MethodsA nested case–control study was conducted using the retrospectively collected data of 106 patients with juvenile-onset nr-axSpA (age at disease onset, <16 years) in the Clinical characteristic and Outcome in Chinese Axial Spondyloarthritis study cohort. Baseline demographic and clinical characteristics and prognosis were reviewed. Logistic regression analyses were performed to investigate risk factors associated with progression to JoAS.ResultsOverall, 58.5% of patients with juvenile-onset nr-axSpA presented with peripheral symptoms at disease onset. In 82.1% of these patients, axial with peripheral involvement occurred during the disease course. The rate of disease onset at >12 years and disease duration of ≤10 years were significantly higher in those with progression to JoAS than in those without progression to JoAS (83.0% vs 52.8%, p=0.001; 92.5% vs 56.6%, p<0.001, respectively). Multivariable logistic regression analysis revealed that inflammatory back pain (IBP) (OR 13.359 (95% CI 2.549 to 70.013)), buttock pain (OR 10.171 (95% CI 2.197 to 47.085)), enthesitis (OR 7.113 (95% CI 1.670 to 30.305)), elevated baseline C reactive protein (CRP) levels (OR 7.295 (95% CI 1.984 to 26.820)) and sacroiliac joint-MRI (SIJ-MRI) positivity (OR 53.821 (95% CI 9.705 to 298.475)) were significantly associated with progression to JoAS.ConclusionPeripheral involvement was prevalent in juvenile-onset nr-axSpA. IBP, buttock pain, enthesitis, elevated baseline CRP levels and SIJ-MRI positivity in patients with the disease are associated with higher risk of progression to JoAS.

Clinical and Genetic Aspects of Juvenile Onset Pompe Disease

Little is known about clinical symptomatology and genetics of juvenile onset Pompe disease (JOPD). The aims of this study were to analyze how these children are diagnosed, what clinical problems they have, and how phenotype is related to genotype. To accomplish this, we analyzed retrospectively data of 34 patients diagnosed after their first and before completion of their 18th birthday. Median age at diagnosis was 3.9 (range 1.1–17) years. Eight patients (23.5%) developed initial symptoms in the first year, 12 (35%) between 1 and 7 years, and 6 (18%) thereafter. Eight (23.5%) had no clinical symptoms at the time of diagnosis. Indications for diagnostics were a positive family history in three (9%), hyperCKemia in eight (23.5%), motor developmental delay in three (9%), and muscle weakness and/or pain in 17 (50%). Rare clinical signs were failure to thrive, recurrent diarrhea, and suspected hepatopathy with glycogen storage. Thirty-two different mutations were identified. Twenty-seven patients (79.5%) carried the milder c.32–13T > G mutation, known to be associated with a broad range of phenotypes. Three out of eight patients manifesting within the first year of life showed generalized muscle weakness, hypertrophic cardiomyopathy, and had to be ventilated during the course of disease, thereby demonstrating clinical overlap with infantile onset Pompe disease.These findings demonstrate that the phenotype of JOPD is broad and that the differential is not only restricted to neuromuscular disorders. Genotypic analysis was useful to delineate subjects with early onset JOPD from those with IOPD, but overall genotype–phenotype correlation was poor.

Difference in clinical profile between juvenile onset and adult-onset systemic lupus erythematosus: a meta-analysis

The aim was to systematically review the studies that compared clinical and serological variation between adult-onset systematic lupus erythematosus (aSLE) andjuvenile-onset systematic lupus erythematosus (jSLE). A comprehensive literature search was done, in various available electronic databases for relevant publication that compared juvenile onset SLE and adult onset SLE. The data of adverse clinical features, serological profile and mortality were extracted. Juvenile onset was defined as <18 years and adult onset was defined as >18 years. The methodological quality of study was assessed by Newcastle Ottawa scale (NOS) criteria and R version 3.3.1 was used for analysis and ORs and 95% CIs, were used as statistical parameter. A total of 14,920 patients; (12,230: aSLE, and 2,690: jSLE) were included. Renal involvement especially nephritis was significantly more in j-SLE OR: 2.18, 95% CI: [1.81;2.62]; I2=10.8% whereas musculoskeletal was significant in aSLE O.R: 0.64; C.I: [0.44; 0.93]; I2=83.4%. Seizure and malar rash were significantly higher in J-SLE OR:1.69, CI: [1.31; 2.18]; I2=31.1%,1.43; C.I [1.04; 1.97]; I2=82%, respectively. Raynaud’s phenomenon and pleuritis were significantly higher in adult onset SLE. Anemia and thrombocytopenia were significantly higher in juvenile onset SLE. Anti-ds DNA, anti-histone, and anti-ribosomal-P were more frequent in juvenile-onset SLE while, anti-Ro was more common in adult-onset disease. The cause of mortality was not significantly different in both groups. Renal biopsy of class III and IV combined and class V were significantly more in adult-onset SLE. SLEDAI was higher in j-SLE. Meta-analysis indicated that, regardless of many similar clinical and serological manifestations, there is still some variation between adult-onset SLE and juvenile-onset SLE. Although, SLE disease is continuum from juvenile to adult but disease aggressive in juvenile onset SLE.