Clinical and genetic characteristics of 9 rare cases with coexistence of dual genetic diagnoses / 中华儿科杂志

Objective: To analyze the clinical and genetic characteristics of pediatric patients with dual genetic diagnoses (DGD). Methods: Clinical and genetic data of pediatric patients with DGD from January 2021 to February 2022 in Peking University First Hospital were collected and analyzed retrospectively. Results: Among the 9 children, 6 were boys and 3 were girls. The age of last visit or follow-up was 5.0 (2.7,6.8) years. The main clinical manifestations included motor retardation, mental retardation, multiple malformations, and skeletal deformity. Cases 1-4 were all all boys, showed myopathic gait, poor running and jumping, and significantly increased level of serum creatine kinase. Disease-causing variations in Duchenne muscular dystrophy (DMD) gene were confirmed by genetic testing. The 4 children were diagnosed with DMD or Becker muscular dystrophy combined with a second genetic disease, including hypertrophic osteoarthropathy, spinal muscular atrophy, fragile X syndrome, and cerebral cavernous malformations type 3, respectively. Cases 5-9 were clinically and genetically diagnosed as COL9A1 gene-related multiple epiphyseal dysplasia type 6 combined with NF1 gene-related neurofibromatosis type 1, COL6A3 gene-related Bethlem myopathy with WNT1 gene-related osteogenesis imperfecta type XV, Turner syndrome (45, X0/46, XX chimera) with TH gene-related Segawa syndrome, Chromosome 22q11.2 microduplication syndrome with DYNC1H1 gene-related autosomal dominant lower extremity-predominant spinal muscular atrophy-1, and ANKRD11 gene-related KBG syndrome combined with IRF2BPL gene-related neurodevelopmental disorder with regression, abnormal movement, language loss and epilepsy. DMD was the most common, and there were 6 autosomal dominant diseases caused by de novo heterozygous pathogenic variations. Conclusions: Pediatric patients with coexistence of double genetic diagnoses show complex phenotypes. When the clinical manifestations and progression are not fully consistent with the diagnosed rare genetic disease, a second rare genetic disease should be considered, and autosomal dominant diseases caused by de novo heterozygous pathogenic variation should be paid attention to. Trio-based whole-exome sequencing combining a variety of molecular genetic tests would be helpful for precise diagnosis.

Analysis of 4 children with DYNC1H1 gene related spinal muscular atrophy with lower extremity predominant 1 / 中华儿科杂志

Objective: To investigate the clinical features and gene variation characteristics of children with dynein cytoplasmic 1 heavy chain 1 (DYNC1H1) gene associated spinal muscular atrophy with lower extremity predominant (SMALED) 1. Methods: The clinical data of 4 SMALED1 children admitted to Peking University First Hospital from December 2018 to May 2021, who were found to have pathogenic variation of DYNC1H1 gene through genetic testing, except for other genes known to be related to motor retardation, were retrospectively summarized to analyze the phenotype and genotype characteristics. Results: There were 3 males and 1 female. The age of onset was 1 year, 1 day, 1 day and 4 months, respectively. The age of diagnosis was 4 years and 10 months, 9 months, 5 years and 9 months, and 3 years and 1 month, respectively. The clinical manifestations were muscle weakness and muscular atrophy of lower limbs, 2 cases with foot deformity, 1 case with early non progressive joint contracture, 1 case with hip dislocation and 1 case with mental retardation. De novo heterozygous missense variations in DYNC1H1 gene were found in all 4 children. According to the rating of American College of medical genetics and genomics, they were all possible pathogenic and pathogenic variations, with p.R598C, p.P776L, p.Y1109D variations had been reported, and p.I1086R variation had not been reported. Conclusions: For those with unexplained lower limb muscle weakness, muscle atrophy, joint contracture and foot deformity, upper limb motor ability related retention, with or without mental retardation, as well as the motor ability progresses slowly, it is necessary to consider the possibility of SMALED1 and the detection of DYNC1H1 gene when necessary.

A family of hereditary protein S deficiency with the onset of pulmonary embolism and literature review / 中华儿科杂志

Objective: To explore the clinical characteristics and genotype of PROS1 gene related hereditary protein S deficiency (PSD) with the onset of pulmonary embolism in children. Methods: A family with pulmonary embolism was diagnosed as hereditary PSD in the Department of Pediatrics of Peking University First Hospital in November 2020, and the clinical data, including clinical manifestations, laboratory tests, imaging and genetic results, were collected for a retrospective research. The family members were also screened for protein S activity and PROS1 gene mutations. A literature search with "PROS1" "protein S deficiency" "homozygous" and "complex heterozygous" as key words was conducted at PubMed, China National Knowledge Infrastructure, and Wanfang Data Knowledge Service Platform (up to October 2021). Case reports of patients with PROS1 gene homozygous or complex heterozygous variants and related clinical features, protein S activity, and genotype were reviewed and analyzed. Results: The proband, a 14-year-old girl, was admitted to the hospital for a 9-day history of coughing and a 4-day history of chest pain in November 2020. After admission, laboratory tests showed that D-dimer was 8.38 mg/L (reference:<0.24 mg/L). An urgent CT pulmonary angiography confirmed bilateral pulmonary embolism and right lower pulmonary infarction, while an ultrasonography showed deep vein thrombosis in her left leg. Further examination revealed that protein S activity was less than 10%. The proband's second sister, a 12-year-old girl, was admitted to the hospital in December 2020. Her protein S activity was 8% and an ultrasonography showed deep vein thrombosis in her right leg. The protein S activity of the proband's father and mother were 36% and 26%, respectively. Trio-whole-exome sequencing detected compound heterozygous PROS1 gene variants (c.-168C>T and c.200A>C (p.E67A)) for the proband and her second sister, that were inherited from her father and mother, respectively. The proband's third sister's protein S activity was 28%; she and the proband's grandfather both carried c.200A>C (p.E67A) variants. The proband and her younger sister were treated with rivaroxaban and responded well during the 3-month follow-up. A total of 1 Chinese report in literature and 18 English literature were retrieved and 14 patients with protein S deficiency caused by homozygous or complex heterozygous variants of PROS1 gene were enrolled, including 8 male and 6 female patients. The ages ranged from 4 days to 35 years. Three patients experienced fulminant purpura or severe intracranial hemorrhage in early neonatal-period, while the remaining 11 patients developed venous thromboembolism in adolescence. Protein S activity was examined in 11 patients, and all showed less than 10% of activity. Missense variants was the most common type of gene variants. Conclusions: For children with pulmonary embolism, if there are no clear risk factors for thrombosis, hereditary protein S deficiency should be considered, and protein S activity should be examined before oral anticoagulant drugs. If protein S activity is less than 10%, protein S deficiency caused by homozygous or complex heterozygous variants should be considered.

Long-term rituximab treatment of refractory idiopathic inflammatory myopathy: A report of 3 cases / 北京大学学报(医学版)

Idiopathic inflammatory myopathies are a group of rare but serious diseases. The treatment of refractory idiopathic inflammatory myopathy is always challenging, especially in children. Three cases of refractory idiopathic inflammatory myopathy treated by rituximab were reported and discussed with the review of relevant literature. All were female with on-set age of 8 years and 6 months, 11 years and 7 months, 4 years and 2 months old, respectively. All had acute onset, presenting with progressive and severe muscle weakness. All lost ambulation within 1 or 2 months, with difficult swallowing and low voice. Respiratory distress occurred in case 2 after an attack of asphyxia due to an aspiration of sputum, and ventilator support was required for 1 month. Rashes were detected at the initial stage of the disease in cases 2 and 3. Patient 2 showed facial erythematous papules, spreading to her neck and hands. Patient 3 showed purplish eyelids with peri-orbital swelling, generalized edema involving all her limbs. Creatine kinase (CK) levels were markedly elevated in all the patients, ranging from 6 000 IU/L to 28 819 IU/L. Anti-SRP antibody was identified in cases 1, and anti-NXP2 antibodies were confirmed in cases 2 and 3. MRI of both thighs in all the patients showed profound muscle and fascial edema. Muscle pathology of patient 1 showed prominent fiber variation and endomysial fibrosis, with overexpression of MHC-Ⅰ. While muscle pathology in patients 2 and 3 showed scattered fiber necrosis, regeneration, endomysial edema without inflammatory cell infiltration. All the patients were diagnosed with idiopathic inflammatory myopathy and failed to the initial treatment including adequate glucocorticoids and high-dose immunoglobulin therapy. Other immunosuppressants (methotrexate, cyclophosphamide) were also tried in cases 2 and 3 with poor response. Then all the patients were treated with rituximab combined with glucocorticoids. Patient 1 regained normal strength and discontinued rituximab at the end of her last follow-up (2 years and 7 mouths). Though calcinosis developed during the follow-up period, significant improvement was noticed in cases 2 and 3 (both regained the ability to walk independently) at the end of their last follow-up after 2 years and 8 months, 3 years and 2 months respectively. Long-term rituximab therapy may improve the prognosis of refractory idiopathic inflammatory myopathy, especially with positive anti-SRP and anti-NXP2 antibodies.

A new alkaloid from Alstonia yunnanensis / 药学学报

Four alkaloids were isolated from the total alkaloids of the twigs and leaves of Alstonia yunnanensis (Apocynaceae) by using silica gel, ODS, Sephadex LH-20, and HPLC chromatography. Structures were determined by physical, chemical and spectroscopic methods and identified as N4-methylpseudoakuammigine (1), pseudoakuammigine (2), vinorine (3), picraline (4). Among them, compound 1 is a new monoterpenoid indole alkaloid.

Clinical and molecular genetic analysis of a family with normokalemic periodic paralysis / 中华儿科杂志

<p><b>OBJECTIVE</b>Periodic paralysis (PP) is one type of skeletal muscle channelopathies characterized by episodic attacks of weakness. It is usually classified into hyperkalemic periodic paralysis (HyperPP), hypokalemic periodic paralysis (HypoPP) and normokalemic periodic paralysis (NormoPP) based on the blood potassium levels. HypoPP is the most common type of these three and NormoPP is the rarest one. The aim of this study was to explore the clinical and genetic features of a Chinese family with normokalemic periodic paralysis (NormoKPP).</p><p><b>METHOD</b>Clinical features of all patients in the family with NormoKPP were analyzed. Genomic DNA was extracted from peripheral blood leukocytes and amplified with PCR. We screened all 24 exons of SCN4A gene and then sequence analysis was performed in those who showed heteroduplex as compared with unaffected controls.</p><p><b>RESULT</b>(1) Fifteen members of the family were clinically diagnosed NormoKPP, and their common features are: onset within infacy, episodic attacks of weakness, the blood potassium levels were within normal ranges, high sodium diet or large dosage of normal saline could attenuate the symptom. One muscle biopsy was performed and examination of light and electronic microscopy showed occasionally degenerating myofibers. (2) Gene of 12 patients were screened and confirmed mutations of SCN4A genes--c. 2111 T > C/p. Thr704Met.</p><p><b>CONCLUSION</b>The study further defined the clinical features of patients with NormoKPP, and molecular genetic analysis found SCN4A gene c. 2111 T > C/p. Thr704Met point mutation contributed to the disease. In line with the autosomal dominant inheritance laws, this family can be diagnosed with periodic paralysis, and be provided with genetic counseling. And the study may also help the clinical diagnosis, guide treatment and genetic counseling of this rare disease in China.</p>

Stevens-Johnson syndrome induced by sodium valproate:a case report and literatures review / 中华实用儿科临床杂志

Objective To explore the clinical diagnosis and treatment of Stevens-Johnson syndrome induced by sodium valproate.Methods The clinical manifestations,investigation findings and treatment of 1 patient with Stevens-Johnson syndrome induced by sodium valproate,and the related literatures were reviewed.Results The patient was a 3.5-year-old girl who was initially diagnosed with epilepsy.After 14 days of monotherapy with oral sodium valproate,an erythematous rash appeared on the face,and gradually spread to her trunk and limbs with severe itching.The rash rapidly got worsened,and developed flakiness and herpetic lesions that involved swelling and ulceration of the lip mucosa.Two days after the rash appeared,she became febrile with body temperature up to 39.5 ℃.Lymphadenectasis and a palpable 2 cm liver edge were found on examination.Her glutamate pyruvate transaminase was 139 IU/L and the concentration of blood ammonia was 108 μmol/L.The administration of sodium valproate was discontinued imme-diately and methylprednisolone intravenous pulse therapy [15 mg/(kg · d)] was administered.Two days later,she was afebrile and the rash gradually resolved within 7 days of treatment.Her liver function also returned to normal.Conclusions A high degree of vigilance against sodium valproate-induced Stevens-Johnson syndrome was crucial to the early clinical diagnosis and successful treatment of this patient.The prompt discontinuation of the causative medication and sufficient corticosteroid hormone therapy can achieve a good outcome.