Clinical, skeletal muscle pathological and genetic characteristics of fatal infantile hypertonic myofibrillar myopathy / 中华实用儿科临床杂志

Objective:To investigate the clinical, skeletal muscle pathological, and genetic characteristics of fatal infantile hypertonic myofibrillar myopathy (FIHMM).Methods:The clinical manifestations, laboratory assessments data and gene sequencing results of 10 patients diagnosed with FIHMM in Shenzhen Children′s Hospital from February 2017 to April 2021 were retrospectively analyzed.Magnetic resonance imaging (MRI) of both musculoskeletal system and the brain, and electromyogram (EMG) were performed in 3 cases, while muscle biopsy was performed in 2 cases.Results:Among these 10 cases, 1 case was from Northeast China and 1 case from East China, while the rest 8 cases were from South China.Eight of the 10 patients were male, and the other 2 cases were female.They were all born normal and not related to each other.The age of onset varied from 2 to 12 months.The main clinical manifestations for all the patients were progressive rigidity of the rectus abdominis (8 cases), neck muscles (7 cases), rectus abdominis (2 cases) and intercostal muscles (1 case), resulting in respiratory failure.Mildly to moderately elevated serum creatine kinase level was detected (436-5 804 IU/L) (reference range: 24-229 IU/L). Complex repetitive discharges can be seen in the EMG, without any myotonic potential.Muscle fiber degeneration, necrosis, and vacuolar degeneration were noted in the histopathological examination of the vastus lateralis and rectus abdominis.An abnormal red granular deposit was observed in a portion of the field of the modified Gomory Trichrome staining.Immunohistochemistry showed substantial deposition of desmin.Under the electron microscopy, the sarcomere structure of the muscle fibers was seriously disordered, with the destruction of Z-bands and the presence of granular deposits.The whole-exome sequencing identified the same homozygous variation c. 3G>A, p.Met1? of CRYAB gene in all the patients, but heterozygous variation in their parents. Conclusions:Axial muscles involvement, such as rectus abdominis rigidity, is the main clinical characteristic of FIHMM.c.3G>A, p.Met1? mutation in the CRYAB gene is a hotspot mutation in Chinese children.

Clinical, myopathological and genetic research of a patient with mitochondrial encephalomyopathy, lactic acidosis and stroke-like episodes/Leigh syndrome overlap syndrome caused by m.10158 T>C mutation / 中华神经科杂志

Objective To report the clinical, myopathological and genetic features of a patient with mitochondrial encephalomyopathy, lactic acidosis and stroke-like episodes (MELAS)/Leigh syndrome (LS) overlap syndrome who carried m.10158 T>C mutation. Methods The patient′s clinical and imaging materials were collected. An open biopsy of right biceps brachii was performed. DNA samples were prepared from the patient and her mother′s blood. Direct sequencing of the complete mitochondrial genome was performed to detect the mtDNA mutation.Western blotting was used to estimate the content of respiratory complexes in the patient′s muscle. Results The patient was a 40-year-old female. She had seizures and lost consciousness for 9 months. Brain MRI findings consisted of asymmetrical lesions in the cerebral cortex of the frontal and temporal lobes, as well as symmetrical lesions bilaterally in the basal ganglia. Muscle biopsy showed typical ragged red fibers. Direct sequencing of the complete mitochondrial genome from blood and muscle of the patient revealed the T-to-C transition at nucleotide position 10158 in the MT-ND3 gene.The mutation rate was 9.31% and 70.0%, respectively.Western blotting demonstrated that the contents of complexes Ⅰ and Ⅳ were significantly lower in the patient′s muscle mitochondria compared with the normal controls (53.1%±1.2% vs 88.6%±1.7%, t=4.08, PC mutation in MT-ND3 gene and DNA test is very important for the diagnosis of the disease.

Clinical, myopathological and genetic research of a patient with distal myopathy caused by caveolin-3 deficiency / 中华神经科杂志

Objective To report the clinical,myopathological and genetic features of a patient with distal myopathy caused by caveolin-3 (CAV3) deficiency.Methods The patient was a 27-year-old female.She had an onset symptom of asymmetric lower extremities weakness.The proximal limb-girdle muscles were involved subsequently.Clinical data of this patient were collected.The leg muscle magnetic resonance imaging (MRI) and an open biopsy of left tibialis anterior muscle were performed.In addition to histological,enzyme histochemical staining and ultrastructural examination,immunohistochemical staining with antibody against CAV3 was done.CAV3 gene was analyzed in the patient and her parents.Results Tl-weighted enhanced skeletal muscle MRI of the lower limbs showed the abnormal signal in distal and proximal muscles.Muscle biopsy showed moderate dystrophic changes and immunostaining for CAV3 showed reduced plasmalemma in the muscle fibers.Gene analysis disclosed a heterozygous c.136G ＞ A (p.Ala46Thr)mutation in the CAV3 gene,and the patient's parents did not have this mutation.Conclusions We report a distal myopathy case caused by c.136G ＞ A (p.Ala46Thr) mutation in the CAV3 gene,who had an onset symptom of asymmetric lower extremities weakness.The proximal limb-girdal muscles were also involved.This would help clinical doctors to know more about this rare myopathy.

Progress of Spinal muscular atrophy with respiratory distress type 1 / 中华实用儿科临床杂志

Spinal muscular atrophy with respiratory distress type 1 (SMARD1) is a rare autosomal recessive neuromuscular disease.It is caused by mutations in the gene immunoglobulin μ-binding protein 2 which resides on chromosome 11 q13.3 and encodes the immunoglobulin μ-binding protein 2.This disorder is characterized by degeneration of anterior horn α-motoneurons and manifesting as irreversible diaphragmatic paralysis,respiratory distress associated with progressive symmetrical muscular weakness,distal lower limbs mainly involved,and muscle atrophy between the first 6 weeks and 6 months of life.Overall,SMARD1 is a poor-prognosis disease that artificial ventilation is needed for the whole life.

A novel mutation in GCH1 gene causes dopa-responsive dystonia / 中华医学遗传学杂志

<p><b>OBJECTIVE</b>To identify potential mutation of the GCH1 gene in a Chinese family affected with dopa-responsive dystonia.</p><p><b>METHODS</b>Genomic DNA of patients was extracted from peripheral blood samples. The 6 exons of the GCH1 gene and at least 100 bp of flanking intronic sequences were amplified with PCR. Potential mutations were screened by direct sequencing. Identified mutation was verified with denaturing high performance liquid chromatography (DHPLC) in 100 healthy controls.</p><p><b>RESULTS</b>All patients were found to be heterozygous for a novel c.597delT (p.Ala200LeufsX5) deletion in the exon 5 of the GCH1 gene. The deletion of T has resulted in formation of a shorter (203 amino acids) truncated non-functional guanosine triphosphate cyclohydrolase I. The same mutation was not found in the 100 controls.</p><p><b>CONCLUSION</b>A novel GCH1 gene frameshifing mutation probably underlies the dopa-responsive dystonia in this Chinese family.</p>

Electroencephalography and follow-up of 128 cases of infantile convulsions with mild gastroenteritis / 中国小儿急救医学

Objective In present study,we aimed to investigate the ictal and interictal electroencephalography (EEG) changes in patients with infantile convulsions with mild gastroenteritis,to understand the evolution of EEG and recurrence of convulsion by follow-up.Methods In this retrospective study,all patients with infantile convulsions with mild gastroenteritis visited our hospital from January 2005 to December 2009 were included,and were followed up for 3 to 7 years.All their clinical data were summarized and analyzed.Results Fist of all,we collected 128 interictal EEGs and 4 ictal (5 episodes) reports.Based on interictal EEGs,no discharge was observed in 63 subjects,and epileptic waves were discovered in other 65 patients.In most cases (48/65) epileptic waves were found to be located in the central area.For all 5 recorded ictal EEGs (2 were from same patient),epileptic waves were originated from different regions.Two months later,epileptic waves disappeared in 52/57 cases,but there were still discharge in 5 cases.Secondly,in the 103 cases who were successfully followed up,96 were seizure free,5 had recurrence during fever (3 cases) or gastroenteritis (2 cases),but remained seizure free for last 1.5 to 3.0 years.Overall,convulsion was recurred in 2 cases and finally diagnosed as epilepsy and then treated with antiepileptic drug,keeping seizure free for recent 1.5 to 2.5 years.Conclusion (1) Discharge can be found in nearly half of interictal EEGs in cases with infantile convulsion with mild gastrocnteritis,and most of them are located in central region.(2) All discharge come from local origin in ictal EEGs.(3) Seizure may recur in cases with infantile convulsion with mild gastroenteritis,especially in the presence of causative factors.Some children have risk of developing epilepsy.

Efficacy of levetiracetam on improving abnormal EEG in seizure-free epileptic children / 中国小儿急救医学

ObjectiveThis clinical study is aimed to investigate whether levetiracetam (LEV) can improve electrocorticogram (EEG) in epileptic children epilepsy patients with better clinical manifestation but abnormal EEG findings.MethodsTotally 39 children from our neurological clinic with partial or complex partial epilepsy seizure were included in present study and assigned equally into three groups receiving different treatment:control group,sodium valproate (VPA) group,and LEV group.Their clinical symptoms had been controlled for over one year by carbamazepine ( CBZ),but EEG results showed clearly abnormal.Epileptiform discharges were observed in routine EEG exams half a month before recruiting.After recruiting,they continued to receive CBZ alone (control group) or co-treated with VPA ( VPA group) or LEV (LEVgroup),respectively.Six months later,EEG was taken again and results were analyzed.ResultsImprovement rate were 9.1％ ( control group),23.1％ ( VPA group),and 66.7％ (LEV group),respectively;Overall statistical difference was reached among three groups ( P＜0.01 ) and between control group and LEV group( P＜0.012 5 ),but no statistical difference between control group and VPA group was reached ( P＞0.0125).ConclusionCo-treatment of LEV in child epilepsy patients receiving CBZ can significantly decrease abnormal EEG discharge frequency during interictal period.

The detection of Rotavirus and Norwalkvirus in stool and cerebrospinal fluid of children with infantile convulsions associated with mild gastroenteritis / 中国小儿急救医学

Objective To explore the common pathogen of infantile convulsions associated with mild gastroenteritis, and to study the differences between the seizures caused by the two kinds of virus.Methods RT-PCR was used to detect Rotavirus (RV) and Norwalkvirus (NoV) in stool and cerebrospinal fluid of 30 cases with infantile convulsions associated with mild gastroenteritis. The differences between the frequency of seizures caused by two kinds of virus were analyzed by statistical methods (two-sample t-test).Results 17/30 (56. 7%) were RV-positive in stool and 3/17 (17. 7%) in cerebrospinal fluid; 6/30 (25.0%) were NoV-positive in stool and 1/6 (16. 7%) in cerebrospinal fluid. The seizure frequency with NoV infection was (4. 33 ± 1.75) times, and RV infection patients was (2. 53 ± 1.12) times (P ＜ 0. 01).The seizure frequency of CSF virus-positive children was (4. 75 ± 1.71) times compared to (2. 63 ± 1.21)times in virus-negative children (P ＜ 0.01). Conclusion The common pathogens causing infantile convulsions associated with mild gastroenteritis were RV and NoV. The degree of NoV infection affecting the central nervous system may be greater than RV. The presence of the virus in cerebrospinal fluid may lead to higher incidence of seizures,but their exact roles related to the occurrence of seizures remain to be further studied.