Biallelic SHQ1 variants in early infantile hypotonia and paroxysmal dystonia as the leading manifestation.

Biallelic SHQ1 variant-related neurodevelopmental disorder is extremely rare. To date, only six affected individuals, from four families, have been reported. Here, we report eight individuals, from seven unrelated families, who exhibited neurodevelopmental disorder and/or dystonia, received whole-genome sequencing, and had inherited biallelic SHQ1 variants. The median age at disease onset was 3.5 months old. All eight individuals exhibited normal eye contact, profound hypotonia, paroxysmal dystonia, and brisk deep tendon reflexes at the first visit. Varying degrees of autonomic dysfunction were observed. One individual had cerebellar atrophy at the initial neuroimaging study, however, three individuals showed cerebellar atrophy at follow-up. Seven individuals who underwent cerebral spinal fluid analysis all had a low level of homovanillic acid in neurotransmitter metabolites. Four individuals who received 99mTc-TRODAT-1 scan had moderate to severe decreased uptake of dopamine in the striatum. Four novel SHQ1 variants in 16 alleles were identified: 9 alleles (56%) were c.997C > G (p.L333V); 4 (25%) were c.195T > A (p.Y65X); 2 (13%) were c.812T > A (p.V271E); and 1 (6%) was c.146T > C (p.L49S). The four novel SHQ1 variants transfected into human SH-SY5Y neuronal cells resulted in a retardation in neuronal migration, suggestive of SHQ1 variant correlated with neurodevelopmental disorders. During the follow-up period, five individuals still exhibited hypotonia and paroxysmal dystonia; two showed dystonia; and one had hypotonia only. The complex interactions among movement disorders, dopaminergic pathways, and the neuroanatomic circuit needs further study to clarify the roles of the SHQ1 gene and protein in neurodevelopment.

Genotype-Phenotype Dissociation in Two Taiwanese Children with Molybdenum Cofactor Deficiency Caused by MOCS2 Mutation.

BACKGROUND: To describe the genotype-phenotype dissociation in two Taiwanese patients with molybdenum cofactor deficiency (MoCoD) caused by MOCS2 gene mutations. PATIENT DESCRIPTION: Patient 1 exhibited early-onset neurological symptoms soon after birth, followed by subsequent myoclonic seizures and movement disorder. The brain magnetic resonance imaging (MRI) showed diffuse brain injury with cystic encephalomalacia along with bilateral globus pallidi involvement, hypoplasia of corpus callosum, and cerebellar atrophy. Patient 2 had a mild phenotype with prominent movement disorder after intercurrent illness, and the brain MRI showed selective injury of the bilateral globus pallidi and the cerebellum. Both patients had markedly low levels of plasma uric acid and harbored the same MOCS2 homozygous c.16C > T mutation. Patient 1 showed chronic regression of developmental milestones and died of respiratory failure at the age of 8 years, whereas patient 2 demonstrated improvement in motor function. CONCLUSION: Genotype-phenotype dissociation could be noted in patients with MoCoD due to MOCS2 mutation. Patients with neonatal seizures, developmental delay, movement disorder, and motor regression after an illness, as well as focal or bilateral involvement of the globus pallidi on the neuroimages, should undergo biochemical testing of plasma uric acid. A pronounced plasma uric acid level is a good indicator of MoCoD. Early diagnosis can allow early provision of adequate genetic counseling.

Prenatal brain disruption in isolated sulfite oxidase deficiency.

BACKGROUND: Isolated sulfite oxidase deficiency (ISOD) is a very rare autosomal recessive inherited neurometabolic disease. The most striking postnatal neuroimaging finding is multicystic encephalomalacia, which occurs rapidly within days to weeks after birth and mimics severe hypoxic-ischemic encephalopathy. The aim of this study was to describe the prenatal neuroimaging features in a neonate and a fetus diagnosed with ISOD. RESULTS: We report an 11-day-old female neonate who presented with feeding difficulties, decreased activity, neonatal seizures, and movement disorders within a few days after birth. Brain MRI at 9 days of age showed cystic lesions over the left frontal and temporal areas, diffuse and evident T2 high signal intensity of bilateral cerebral cortex, and increased T2 signal intensity of the globus pallidi. A pronounced low level of plasma cysteine and normal level of plasma uric acid were noted. Mutation analysis of SUOX revealed homozygous c.1200C > G mutations, resulting in an amino acid substitution of tyrosine to a stop codon (Y400X). The diagnosis of ISOD was made. The brain MRI of a prenatally diagnosed ISOD fetus of the second pregnancy of the mother of the index case showed poor gyration and differentiation of cortical layers without formation of cystic lesions at gestational age 21 weeks. CONCLUSION: Cystic brain destruction might occur prenatally and neurodevelopment of gyration and differentiation of the cortical layers in the developing brain could be affected by sulfite accumulation early during the second trimester in ISOD patients. This is the first description of the prenatal neurodevelopment of brain disruption in ISOD.

Epileptic seizure in primary intracranial sarcoma: a case report and literature review.

PURPOSE: The aim of this study is to describe epileptic seizures in patients with primary intracranial sarcomas. METHODS: We report a 17-year-old girl diagnosed with primary high-grade intracranial sarcoma with initial clinical manifestation of nonconvulsive status epilepticus. Literature reports between 2000 and 2014, relevant to primary intracranial sarcomas in children, were reviewed. The clinical presentations and neurological outcomes were analyzed. RESULTS: Eleven of 29cases (38 %), 8 males and 3 females, who exhibited epileptic seizures as one of the initial symptoms and diagnosed with primary intracranial sarcomas were collected. The median age of disease onset was 5 years. The two most common seizure types were generalized seizures (45 %) and status epilepticus (36 %). Nine of 11 patients (82 %) had tumor growth involving the frontal lobe. Nine cases had the median duration of follow-up 1.7 years, of which 6 cases showed tumor recurrence and 3 cases died during the period of follow-up. CONCLUSIONS: Epileptic seizures as one of the clinical manifestations are uncommon. The two most common seizure types were generalized seizures and status epilepticus. The most frequent location of primary intracranial sarcoma-related seizures was the frontal lobe. The clinical outcome varied.

Lactate peak on brain MRS in children with syndromic mitochondrial diseases.

BACKGROUND: Brain magnetic resonance spectroscopy (MRS) has been reported to be a valuable noninvasive tool in the diagnosis of some rare diseases. In this study, our aim was to assess lactate peak on single-voxel proton MRS in children with syndromic mitochondrial diseases (MDs). METHODS: From March 2004 to November 2010, 14 patients who were diagnosed with syndromic MDs underwent single-voxel proton MRS examination. The volume of interest was positioned on axial magnetic resonance imaging (MRI), and voxels were sampled using short (35 milliseconds), intermediate (144 milliseconds), or long (288 milliseconds) echo times for determination of lactate at 1.33 parts/million. RESULTS: Twelve of fourteen patients (85.7%) exhibited lactate peaks on the initial single-voxel proton MRS, and all of them showed abnormal MRI findings. The correlations of lactate level in blood and lactate peak on single-voxel proton MRS were inconsistent. Among the 12 patients, eight (66.7%) had corresponding elevated levels of blood lactate, and four (33.3%) had normal levels of blood lactate. Compared with a positive rate of 85.7% for patients with lactate peaks on the single-voxel proton MRS, the positive rates for diagnosing syndromic MDs by using electron microscopic examination of muscle biopsy, oral glucose lactate stimulation test, and blood lactate level were 100%, 91.7%, and 71.4%, respectively. CONCLUSION: Lactate acquisition on single-voxel proton MRS provides a noninvasive and complementary tool for the diagnosis of syndromic MDs, especially in children with abnormal signal changes on the brain MRI or a normal blood lactate level.

Obscure manifestations of Salmonella subdural empyema in children: case report and literature review.

PURPOSE: Salmonella intracranial infections, including subdural empyema and brain abscess, are rare clinical manifestations in children. The aim of this study is to investigate the clinical course of Salmonella subdural empyema in infants and children. METHODS: We report a 9-month-old female infant diagnosed as Salmonella subdural empyema with clinical features of prolonged fever for more than 2 months and episodic focal seizures. Literature published between 1986 and 2010 relevant to Salmonella subdural empyema in children were reviewed. The clinical presentations and laboratory findings were analyzed. RESULTS: Seventeen cases with Salmonella subdural empyema, including our index case, has been reported with detailed clinical presentation. Fever (17/17; 100%), symptoms and signs of increased intracranial pressure (8/17; 47%), seizures (8/17; 47%), and limb paralysis (8/17; 47%) were the most frequent clinical features. Among these cases, unknown causative organism prior to surgery (11/17; 65%) and prolonged fever for more than 3 weeks (5/17; 29%) were also noticed. Sixteen out of 17 patients (94%) required surgical intervention for treatment. The morbidity rate and mortality rate were 29% (5/17) and 6% (1/17), respectively. CONCLUSION: Subdural empyema is considered to be a disease with rapid progression. However, the cases caused by Salmonella species may present a slow disease course. Surgical intervention is sometimes the only way to detect the pathogen.

Corneal clouding: An infrequent ophthalmic manifestation of mitochondrial disease.

Corneal clouding is uncommon in infants and children but when present in this age group, it is often associated with mucopolysaccharidoses or Fabry disease. This report describes the case of an 11-year-old male who demonstrated poor weight gain, short stature, segmental myoclonus, and learning problems from 5 years of age followed by general weakness and extremely poor balance. Corneal clouding was evident as a result of a blurred vision complaint at 9 years of age. Both urine metabolic screening for mucopolysaccharidoses and analysis of lysosomal enzymes displayed negative findings. Clinical conditions worsened, including ptosis, progressive weakness, and positive Gowers' sign. Oral glucose lactate stimulation test was positive, therefore a muscle biopsy was performed at 11 years of age. Light microscopy of muscle biopsy disclosed abundant ragged red fibers; electron microscopy revealed abnormal mitochondria in terms of tubular cristae, concentrated cristae, stacking cristae, and round granular patterns of inclusion bodies in the matrix. Thus mitochondrial disease was diagnosed. We conclude that mitochondrial disease should be added to the list of differential diagnosis of corneal clouding in children, especially in cases with normal urine metabolic screening for mucopolysaccharidoses or when assays of lysosomal enzymes appear normal.