Bilateral horizontal gaze palsy in an 8‐year‐old girl: A rare case with NDUFS4 gene mutation

We report a patient with complex clinical presentation including multiple neurological symptoms and eye involvement. Upon genetic investigation, the patient was found to carry a novel homozygous mutation in the NDUFS4 gene, thus adding to the heterogeneity of Leigh syndrome clinical presentation.     

一种新的线粒体DNA基因突变:线粒体脑肌病伴高乳酸血症和卒中样发作综合征1例基因与残障特征分析

背景线粒体脑肌病伴高乳酸血症和卒中样发作综合征(MELAS)是线粒体脑肌病中最常见的一种临床类型,多种线粒体基因突变均可导致MELAS.目的探讨1例MELAS患者的临床表现和线粒体基因突变的关系.设计临床、病理和基因分析对照研究.地点和对象实验在解放军济南军区总医院神经内科病房、神经病理实验室和神经分子生物学实验室进行.患者,男,13岁,因发作性头痛、呕吐,肢体抽搐1个月于2001-06-04入院,入院后逐渐出现失明和智能减退.血乳酸和丙酮酸水平升高,临床诊断MELAS.干预对患者行头颅MRI检查、脑活检病理检查和线粒体基因分析.主要观察指标临床表现特点、MRI病变特征、脑组织病理改变特点以及线粒体基因突变类型.结果患者不存在能引起MELAS的较常见的突变,但在线粒体3314～3589之间有276 bp的碱基缺失.结论线粒体DNA 3314～3589位点之间276 bp的碱基缺失可能是能够导致MELAS的一种新的基因突变类型,也是导致患者出现失明、癫痫和痴呆的原因.     

Genetic liver disease in adults. Early recognition of the three most common causes

The most common clinically important genetic diseases leading to liver dysfunction in adults are Wilson's disease, HHC, and alpha 1AT deficiency. Advances in molecular biology have led to the identification and characterization of the genetic defects in these conditions. Consequently, genetic testing for disease-causing mutations is now available for most of these disorders. However, it is important to understand the strengths and limitations of such testing. Genetic testing is probably most helpful in HHC because of the high frequency of the homozygous C282Y mutation among patients of northern European descent and the relatively high penetrance of the mutation with regard to clinical expression. Genetic testing is much less helpful in the other genetic liver diseases because of the high number of possible mutations and variable clinical expression. However, noninvasive phenotype-based screening tests and specific treatments are available for most genetic liver diseases. Appropriate use of screening tests in routine clinical practice can assist in early identification of genetic liver diseases and prevent development of end-organ damage.     

酷似免疫性脑炎的线粒体脑肌病伴乳酸酸中毒及卒中样发作综合征的诊断学特征

目的探讨酷似免疫性脑炎的线粒体脑肌病伴乳酸酸中毒及卒中样发作(MELAS)综合征的临床、神经电生理及影像学改变的诊断学特征,总结诊疗过程。 方法回顾性分析1例酷似免疫性脑炎的MELAS综合征的发病过程及临床资料,并复习相关文献。 结果患儿曾以发热、头痛、恶心、呕吐、视物模糊、眼球阵挛、步态不稳等相似症状分别于3,6个月前误诊为病毒性脑炎、免疫性脑炎两次住院,经治疗症状逐渐好转出院。现以相同症状加重并出现视物不清、行走困难再次入院。检查脑脊液常规及抗N-甲基-D-天冬氨酸受体(NMDA-R)抗体阴性,脑电图显示右侧枕部、后颞部大量散发－阵发性棘波/棘慢复合波、尖波/尖慢复合波,可波及右侧顶部;头颅磁共振(MRI)表现多样,可累及皮质和髓质,以灰质为主,表现为脑回明显肿胀,脑沟变窄、变浅,DWI呈弥散受限高信号,晚期脑组织可出现局部软化、脑萎缩改变,病灶可反复出现,基因检测A3243G位点突变,最终确诊为MELAS综合征。 结论临床症状酷似免疫性脑炎的患儿,遇有病情不稳、症状反复出现,应做进一步检查,排除或确诊是否为MELAS综合征。     

Kagami-Ogata syndrome: an important differential diagnosis to Beckwith-Wiedemann syndrome

We report the case of a fetus with sonographic characteristics of Beckwith-Wiedemann syndrome (BWS). A 30-year-old gravida 2 para 1 was referred to our fetal medicine unit with an omphalocele. Fetal macrosomia, organomegaly, and polyhydramnios but no macroglossia were detected and BWS was suspected. Genetic testing for BWS did not confirm the suspected diagnosis as the karyotype was normal. Symptomatic polyhydramnios led to repeated amnioreductions. At 35 + 5 weeks of gestation, a female neonate of 3660 g was delivered with APGAR scores of 6/7/8, after 1/5/10 min, respectively. The abnormal shape of the thorax, facial dysmorphism, need for ventilation, and generalized muscular hypotonia led to the suspicion of Kagami-Ogata syndrome (KOS), which was confirmed by genetic testing. KOS in our patient was caused by a large deletion in the MEG3-region on chromosome 14q32 affecting the maternal allele. In this report, we highlight the notion that when sonographic signs suggestive of BWS such as macrosomia, polyhydramnios, and omphalocele are present and genetic testing does not confirm the suspected diagnosis, KOS should be tested for.     

双侧纹状体坏死家系遗传基因研究

目的报道一个双侧纹状体坏死家系的临床特征以及基因学改变特点。方法于中国西北偏远地区收集一个双侧纹状体坏死家系,家系分析显示为常染色体隐性遗传可能性大。该家系3例患者5～7岁发病,隐袭起病,症状缓慢进展,表现全身肌张力障碍,至20岁左右几乎不能下地,呈扭转痉挛状态。头颅磁共振检查提示双侧壳核病变。对该家系进行了NUP62、SLC19A3、SLC25A19、PANK2基因测序以及线粒体基因全长测序。结果该家系临床特点以及影像学表现与目前已知基因的临床表型有一定的差异。PANK2、SLC25A19、SLC19A3基因序列分析均未发现基因突变;NUP62基因发现cDNA337G-A杂合突变(pG113S突变),3个患者以及其正常的妹妹和患者父亲、奶奶携带该突变。线粒体基因全长测序发现43个已经报道的变异。结论该家系为常染色体隐性遗传,一个杂合突变不能解释其表现,且正常个体也携带该突变。因此该家系从临床表型和基因学检查提示有可能为一种新的疾病类型。     

A case of prenatal diagnosis of 16q24.3 microdeletion KBG syndrome and review of the literature

Here we report a case of a 16q24.3 microdeletion KBG syndrome (KBGS) in a fetus. The absence of a well‐defined phenotype poses a challenge for genetic diagnosis. This report demonstrated that the high‐risk chromosome 21 trisomy could be the first manifestation of KBGS, as observed in this case.     

Avoiding pitfalls in molecular genetic testing: case studies of high-resolution array comparative genomic hybridization testing in the definitive diagnosis of Mowat-Wilson syndrome

The molecular testing options available for the diagnosis of genetic disorders are numerous and include a variety of different assay platforms. The consultative input of molecular pathologists and cytogeneticists, working closely with the ordering clinicians, is often important for definitive diagnosis. Herein, we describe two patients who had long histories of unexplained signs and symptoms with a high clinical suspicion of an underlying genetic etiology. Initial molecular testing in both cases was negative, but the application of high-resolution array comparative genomic hybridization technology lead to definitive diagnosis in both cases. We summarize the clinical findings and molecular testing in each case, discuss the differential diagnoses, and review the clinical and pathological findings of Mowat-Wilson syndrome. This report highlights the importance for those involved in molecular testing to know the nature of the underlying genetic abnormalities associated with the suspected diagnosis, to recognize the limitations of each testing platform, and to persistently pursue repeat testing using high-resolution technologies when indicated. This concept is applicable to both germline and somatic molecular genetic testing.     

Neurofibromatosis type 1: should we screen for other genetic syndromes? A case report of co‐existence with multiple endocrine neoplasia 2A

Background  NF 1 is a genetic disorder with an autosomal dominant pattern of inheritence. It is associated with neoplastic disorders mainly derived from the neural seath. However, the co-existence of NF1 with the full spectrum of MEN 2A has rarely been reported. The aim of the study was to investigate the presence of secondary neoplasias in a patient with diagnosed NF1, and in particular the presence of hyperparathyroidism and the possible co-existence with another pheochromocytoma-related syndrome.
Methods  We report a case of a 70 years old female patient who had NF1. The patient was referred to our center and was diagnosed with an isolated pheochromocytoma of the right adrenal gland for which she underwent right adrenalectomy. We further investigated for the presence of another pheochromocytoma-related syndrome and in particular for the presence of hyperparathyroidism and medullary thyroid cancer. Molecular screening for germline mutations of the genes NF1, RET and VHL has also been performed.
Results  The patient was further diagnosed with hyperparathyroidism and medullary thyroid cancer, having the full spectrum of the clinical picture of the MEN2A syndrome. The genetic testing revealed the germline mutation for NF1 but not for the RET proto-oncogene which is generally found in MEN2A cases.
Conclusion  To our knowledge this is a rare case of co-existence of two pheochromocytoma-related genetic syndromes, and generates the question of whether all patients with these syndromes should undergo a thorough clinical and laboratory investigation for the possibility of another co-existing pheochromocytoma-related genetic syndrome.     

Pyogenic arthritis,pyoderma gangrenosum,and acne syndrome in a Chinese family: A case report and review of literature

BACKGROUNDPyogenic arthritis, pyoderma gangrenosum, and acne (PAPA) syndrome is a rare autosomal dominant genetic disease characterized by severe autoimmune inflammation, caused by mutations in the PSTPIP1 gene. Due to PAPA heterogeneous clinical manifestation, misdiagnosis or delayed diagnoses are difficult to avoid. With the use of whole-exome sequencing, we identified a missense mutation in the PSTPIP1 gene in a Chinese family. To the best of our knowledge, this is the first case of PAPA reported in China.CASE SUMMARYA 9-year-old boy suffered from recurrent aseptic pyogenic arthritis triggered by minor trauma or few obvious predisposing causes for more than 3 years. Pyogenic arthritis occurred every 3-5 mo, affecting his knees, elbows, and ankle joints. Treatments, such as glucocorticoids, antibiotics, even surgeries could alleviate joints pain and swelling to some extent but could not inhibit the recurrence of arthritis. Similar symptoms were present in his younger brother but not in his parents. According to the whole-exome sequencing, a missense mutation in exon 11 of the PSTPIP1 gene (c.748G>C; p.E250Q) was detected in the boy, his younger brother and his father. Taking into account the similar phenotypic features with PAPA syndrome reported previously, we confirmed a diagnosis of PAPA syndrome for the family.CONCLUSIONIn this case, a missense mutation (c.748G>C; p.E250Q) in PSTPIP1 gene was identified in a Chinese family with PAPA syndrome. Previous studies emphasize the fact that PAPA syndrome is hard to diagnose just through the clinical manifestations owing to its heterogeneous expression. Genetic testing is an effectual auxiliary diagnostic method, especially in the early stages of pyogenic arthritis. Only if we have a deep understanding and rich experience of this rare disease can we make a prompt diagnosis, develop the best clinical treatment plan, and give good fertility guidance.     

Late-onset Leigh syndrome without delayed development in China: A case report

BACKGROUNDLeigh syndrome (LS) is one of the most common mitochondrial diseases in infants and children. LS often manifests as early-onset with delayed phenotypic development. However, late-onset LS with normal development and white matter lesions in the brain is rarely reported, thereby highlighting the phenotypic variability of LS expression. CASE SUMMARYWe report a 12-year-old boy who presented with an unusual late-onset and fulminant form of LS that is maternally inherited without developmental delay. The patient was admitted to the hospital with symptoms of ptosis and somnolence, and died within 2 mo. Analysis of peripheral blood leukocytes showed a homoplasmic m.9176T>C mutation in the patient. Magnetic resonance imaging also revealed lesions in bilateral white matter as well as symmetrical lesions in the basal ganglia and brain stem. The patient was diagnosed with LS. The patient was treated with vitamin C, vitamin D, and adenosine-triphosphate. The patient died within 2 mo of hospital admission.CONCLUSIONLS can present in both infants and older children with different phenotypes.     

MELAS误诊为单纯疱疹病毒性脑炎一例

线粒体脑肌病伴高乳酸血症和卒中样发作（MELAS）是母系遗传性线粒体疾病,临床表现多样,易与单纯疱疹病毒性脑炎（HSE）混淆。该文报道1例初诊时误诊为HSE的MELAS患者,该例患者因反复发热、头痛、肢体抽搐1个月,再发头痛1周就诊,入院时初步疑诊为HSE,予以抗病毒治疗无效,进一步行血液和尿液基因检测确诊为MELAS。MELAS可与不典型的HSE表现相似,应谨慎鉴别。脑脊液和（或）血清乳酸升高和基底节钙化有助于诊断MELAS,MELAS的线粒体DNA突变可通过血液和尿液基因检测,而不需要采用肌肉活组织检查这样的有创检查。     

儿童进行性家族性肝内胆汁淤积症3型一例并文献复习

目的 探讨进行性家族性肝内胆汁淤积症3型（PFIC3）的临床及遗传学特点。方法 报道1例PFIC3病例。以“儿童”“进行性家族性肝内胆汁淤积症3型”（包括中英文）为检索词,对以下数据库的相关论文进行检索：PubMed、中国生物医学文献服务系统（SinoMed）、CNKI、万方数据知识服务平台、维普中文科技期刊数据库,收...     

Complications after cardiovascular surgery in a case of undiagnosed spinal-bulbar muscular atrophy (Kennedy disease)

Neurodegenerative diseases are often associated with life-threatening declines in respiratory and swallowing mechanisms. We report the case of a 70-year-old man who had postoperative dysphagia and respiratory failure that required reintubation after coronary artery bypass surgery. Impairment of the patient's speech, swallowing, and respiratory mechanisms identified during postoperative clinical and instrumental examinations was suggestive of a neurodegenerative disease. Genetic testing confirmed a diagnosis of spinal-bulbar muscular atrophy (Kennedy disease). This case report aims to highlight increased morbidity in patients with undiagnosed neuromuscular disorders in the critical care setting and the benefits of vigilant postoperative monitoring and multidisciplinary involvement throughout the care of complex patients.     

Multiple endocrine neoplasia type 2; MEN 2

Multiple endocrine neoplasia type 2 (MEN 2) is an inherited disorder as an autosomal dominant trait, characterized by medullary thyroid carcinoma (MTC). MEN 2 is classified with associated diseases into three subtypes: MEN 2A, MEN 2B and familial MTC. It has recently been shown to be associated with germline mutation in the RET proto-oncogene. Genetic testing allows easily for accurate diagnosis of presymptomatic gene carriers and surgical treatment at an early stage of the disease. In this review we delivered the classification, clinical feature, mutation in RET, mutation analysis, and management of MEN 2, and we discuss recent progress of research on the molecular basis and how genetic testing could be used for clinical management of affected patients or individuals in at-risk families.     

JAK2 V617F in myeloid disorders: molecular diagnostic techniques and their clinical utility: a paper from the 2005 William Beaumont Hospital Symposium on Molecular Pathology

In early 2005, several groups of investigators studying myeloid malignancies described a novel somatic point mutation (V617F) in the conserved autoinhibitory pseudokinase domain of the Janus kinase 2 (JAK2) protein, which plays an important role in normal hematopoietic growth factor signaling. The V617F mutation is present in blood and marrow from a large proportion of patients with classic BCR/ABL-negative chronic myeloproliferative disorders and of a few patients with other clonal hematological diseases such as myelodysplastic syndrome, atypical myeloproliferative disorders, and acute myeloid leukemia. The JAK2 V617F mutation causes constitutive activation of the kinase, with deregulated intracellular signaling that mimics continuous hematopoietic growth factor stimulation. Within 7 months of the first electronic publication describing this new mutation, clinical molecular diagnostic laboratories in the United States and Europe began offering JAK2 mutation testing on a fee-for-service basis. Here, I review the various techniques used by research groups and clinical laboratories to detect the genetic mutation underlying JAK2 V617F, including fluorescent dye chemistry sequencing, allele-specific polymerase chain reaction (PCR), real-time PCR, DNA-melting curve analysis, pyrosequencing, and others. I also discuss diagnostic sensitivity, performance, and other practical concerns relevant to the clinical laboratorian in addition to the potential diagnostic utility of JAK2 mutation tests.     

Molecular genetic analysis of long QT syndrome in Norway indicating a high prevalence of heterozygous mutation carriers

Mutations in the KCNQ1, HERG, SCN5A, minK and MiRP1 genes cause long QT syndrome (LQTS), of which there are two forms: the Romano Ward syndrome and the Jervell and Lange-Nielsen syndrome. We have performed DNA sequencing of the LQTS-associated genes in 169 unrelated patients referred for genetic testing with respect to Romano Ward syndrome and in 13 unrelated patients referred for genetic testing with respect to Jervell and Lange-Nielsen syndrome. A total of 37 different mutations in the 5 genes, of which 20 were novel, were identified. Among patients with the most stringent clinical criteria of Romano Ward syndrome, a mutation was identified in 71%. Twelve of the 13 unrelated patients referred for genetic testing with respect to Jervell and Lange-Nielsen syndrome were provided with a molecular genetic diagnosis. Cascade genetic screening of 505 relatives of index patients with molecularly defined LQTS identified 251 mutation carriers. The observed penetrance was 41%. Although caution must be exerted, the prevalence of heterozygotes for mutations in the LQTS-associated genes in Norway could be in the range 1/100-1/300, based on the prevalence of patients with Jervell and Lange-Nielsen syndrome.     

Mechanisms of mitochondrial diseases

Mitochondria are essential organelles with multiple functions, the most well known being the production of adenosine triphosphate (ATP) through oxidative phosphorylation (OXPHOS). The mitochondrial diseases are defined by impairment of OXPHOS. They are a diverse group of diseases that can present in virtually any tissue in either adults or children. Here we review the main molecular mechanisms of mitochondrial diseases, as presently known. A number of disease-causing genetic defects, either in the nuclear genome or in the mitochondria's own genome, mitochondrial DNA (mtDNA), have been identified. The most classical genetic defect causing mitochondrial disease is a mutation in a gene encoding a structural OXPHOS subunit. However, mitochondrial diseases can also arise through impaired mtDNA maintenance, defects in mitochondrial translation factors, and various more indirect mechanisms. The putative consequences of mitochondrial dysfunction on a cellular level are discussed.     

Recurrent Near-syncope with Flushing

Episodic vasomotor instability with flushing is an uncommon presentation that is suggestive of an endocrine etiology. This report is the case of a 42-year-old woman who presented to the ED 5 times in a 2-week period for recurrent, self-limited episodes of light-headedness associated with tachycardia, hypertension, and flushing. The patient's diagnosis eluded detection in both the outpatient and the inpatient settings for several months. The clinical diagnosis was ultimately confirmed by biochemical test samples obtained in the ED during a subsequent symptomatic event. The differential diagnosis of this patient's presentation includes pheochrom-ocytoma, carcinoid syndrome, medullary thyroid carcinoma, systemic mastocytosis, and other endocrine and toxicologic diseases. ED management of the patient with transient yet significant vasomotor changes includes a workup for syncope, initiation of focused biochemical investigations, referral to the appropriate consultant, and consideration for admission.