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Concept: Syndromes

168

Deletion and duplication of the -3.7-Mb region in 17p11.2 result in two reciprocal syndrome, Smith-Magenis syndrome and Potocki-Lupski syndrome. Smith-Magenis syndrome is a well-known developmental disorder. Potocki-Lupski syndrome has recently been recognized as a microduplication syndrome that is a reciprocal disease of Smith-Magenis syndrome. In this paper, we report on the clinical and cytogenetic features of two Korean patients with Smith-Magenis syndrome and Potocki-Lupski syndrome. Patient 1 (Smith-Magenis syndrome) was a 2.9-yr-old boy who showed mild dysmorphic features, aggressive behavioral problems, and developmental delay. Patient 2 (Potocki-Lupski syndrome), a 17-yr-old boy, had only intellectual disabilities and language developmental delay. We used array comparative genomic hybridization (array CGH) and found a 2.6 Mb-sized deletion and a reciprocal 2.1 Mb-sized duplication involving the 17p11.2. These regions overlapped in a 2.1 Mb size containing 11 common genes, including RAI1 and SREBF.

Concepts: DNA, Genetics, Copy number variation, Genome, Syndromes, Down syndrome, Array comparative genomic hybridization, Comparative genomic hybridization

157

Generalized joint hypermobility (GJH) is highly prevalent among patients diagnosed with chronic pain. When GJH is accompanied by pain in ≥4 joints over a period ≥3 months in the absence of other conditions that cause chronic pain, the hypermobility syndrome (HMS) may be diagnosed. In addition, GJH is also a clinical sign that is frequently present in hereditary diseases of the connective tissue, such as the Marfan syndrome, osteogenesis imperfecta, and the Ehlers-Danlos syndrome. However, within the Ehlers-Danlos spectrum, a similar subcategory of patients having similar clinical features as HMS but lacking a specific genetic profile was identified: Ehlers-Danlos syndrome hypermobility type (EDS-HT). Researchers and clinicians have struggled for decades with the highly diverse clinical presentation within the HMS and EDS-HT phenotypes (Challenge 1) and the lack of understanding of the pathological mechanisms that underlie the development of pain and its persistence (Challenge 2). In addition, within the HMS/EDS-HT phenotype, there is a high prevalence of psychosocial factors, which again presents a difficult issue that needs to be addressed (Challenge 3). Despite recent scientific advances, many obstacles for clinical care and research still remain. To gain further insight into the phenotype of HMS/EDS-HT and its mechanisms, clearer descriptions of these populations should be made available. Future research and clinical care should revise and create consensus on the diagnostic criteria for HMS/EDS-HT (Solution 1), account for clinical heterogeneity by the classification of subtypes within the HMS/EDS-HT spectrum (Solution 2), and create a clinical core set (Solution 3).

Concepts: Collagen, Syndromes, Marfan syndrome, Genetic disorders, Connective tissue, Ehlers-Danlos syndrome, Hypermobility, Diseases involving the fasciae

50

The theory of myofascial pain syndrome (MPS) caused by trigger points (TrPs) seeks to explain the phenomena of muscle pain and tenderness in the absence of evidence for local nociception. Although it lacks external validity, many practitioners have uncritically accepted the diagnosis of MPS and its system of treatment. Furthermore, rheumatologists have implicated TrPs in the pathogenesis of chronic widespread pain (FM syndrome). We have critically examined the evidence for the existence of myofascial TrPs as putative pathological entities and for the vicious cycles that are said to maintain them. We find that both are inventions that have no scientific basis, whether from experimental approaches that interrogate the suspect tissue or empirical approaches that assess the outcome of treatments predicated on presumed pathology. Therefore, the theory of MPS caused by TrPs has been refuted. This is not to deny the existence of the clinical phenomena themselves, for which scientifically sound and logically plausible explanations based on known neurophysiological phenomena can be advanced.

Concepts: Scientific method, Critical thinking, Rheumatology, Science, Syndromes, Pain, Myofascial pain syndrome, Ailments of unknown etiology

37

The boom in computer use and concurrent high rates in musculoskeletal complaints and carpal tunnel syndrome (CTS) among users have led to a controversy about a possible link. Most studies have used cross-sectional designs and shown no association. The present study used longitudinal data from two large complementary cohorts to evaluate a possible relationship between CTS and the performance of computer work.

Concepts: Cross-sectional study, Syndromes, Computer, Computer program, Wrist, Carpal tunnel, Carpal tunnel syndrome, Median nerve

31

Phantom vibration syndrome is a type of hallucination reported among mobile phone users in the general population. Another similar perception, phantom ringing syndrome, has not been previously described in the medical literature.

Concepts: The Canon of Medicine, Avicenna, Syndromes, Mobile phone, Rotary dial, Push-button telephone, Illusion, Hallucinations in the sane

29

We have limited knowledge about the association between the composition of the intestinal microbiota and clinical features of irritable bowel syndrome (IBS). We collected information on the fecal and mucosa-associated microbiota of patients with IBS and evaluated whether these were associated with symptoms.

Concepts: Bacteria, Gut flora, Constipation, Intestine, Gastroenterology, Syndromes, Irritable bowel syndrome, Flatulence

29

Many non-musculoskeletal complaints in EDS-HT may be related to dysautonomia. This study therefore aims to investigate whether dysautonomia is present and to explore the underlying mechanisms.

Concepts: Syndromes, Marfan syndrome, Ehlers-Danlos syndrome

29

Context: Recently, new clinically important information regarding Klinefelter syndrome (KS) has been published. We review aspects of epidemiology, endocrinology, metabolism, body composition, and neuropsychology with reference to recent genetic discoveries. Evidence Acquisition: PubMed was searched for “Klinefelter,” “Klinefelter’s,” and “XXY” in titles and abstracts. Relevant papers were obtained and reviewed, as well as other articles selected by the authors. Evidence Synthesis: KS is the most common sex chromosome disorder in males, affecting one in 660 men. The genetic background is the extra X-chromosome, which may be inherited from either parent. Most genes from the extra X undergo inactivation, but some escape and serve as the putative genetic cause of the syndrome. KS is severely underdiagnosed or is diagnosed late in life, roughly 25% are diagnosed, and the mean age of diagnosis is in the mid-30s. KS is associated with an increased morbidity resulting in loss of approximately 2 yr in life span with an increased mortality from many different diseases. The key findings in KS are small testes, hypergonadotropic hypogonadism, and cognitive impairment. The hypogonadism may lead to changes in body composition and a risk of developing metabolic syndrome and type 2 diabetes. The cognitive impairment is mainly in the area of language processing. Boys with KS are often in need of speech therapy, and many suffer from learning disability and may benefit from special education. Medical treatment is mainly testosterone replacement therapy to alleviate acute and long-term consequences of hypogonadism as well as treating or preventing the frequent comorbidity. Conclusions: More emphasis should be placed on increasing the rate of diagnosis and generating evidence for timing and dose of testosterone replacement. Treatment of KS should be a multidisciplinary task including pediatricians, speech therapists, general practitioners, psychologists, infertility specialists, urologists, and endocrinologists.

Concepts: Medicine, Endocrinology, Syndromes, Klinefelter's syndrome, Aneuploidy, Y chromosome, X chromosome, Mosaic

29

Introduction.  Persistent genital arousal disorder (PGAD) is a potentially debilitating disorder of unwanted genital sensation and arousal that is generally spontaneous and unrelenting. Since its first description in 2001, many potential etiologies and management strategies have been suggested. Aim.  To review the literature on PGAD, identify possible causes of the disorder, and provide approaches to the assessment and treatment of the disorder based on the authors' experience and recent literature. Methods.  PubMed searches through July 2012 were conducted to identify articles relevant to persistent sexual arousal syndrome and PGAD. Main Outcome Measures.  Expert opinion was based on review of the medical literature related to this subject matter. Results.  PGAD is characterized by persistent sensations of genital arousal in the absence of sexual stimulation or emotion, which are considered unwanted and cause the patient at least moderate distress. The proposed etiologies of PGAD are plentiful and may involve a range of psychologic, pharmacologic, neurologic, and vascular causes. PGAD has been associated with other conditions including overactive bladder and restless leg syndrome. Assessment should include a through history and physical exam and tailored radiologic studies. Treatment should be aimed at reversible causes, whether physiologic or pharmacologic. All patients should be considered for cognitive therapy including mindfullness meditation and acceptance therapy. Conclusions.  PGAD likely represents a range of conditions manifesting in unwanted genital sensations. Successful treatment requires a multidisciplinary approach and consideration of all reversible causes as well as cognitive therapy. Facelle TM, Sadeghi-Nejad H, and Goldmeier D. Persistent genital arousal disorder: Characterization, etiology, and management. J Sex Med **;**:**-**.

Concepts: Medicine, Sexual intercourse, Causality, The Canon of Medicine, Syndromes, Sexual arousal, Restless legs syndrome, Persistent genital arousal disorder

29

JAGGED1 mutations cause Alagille syndrome, comprising a constellation of clinical findings, including biliary, cardiac and craniofacial anomalies. Jagged1, a ligand in the Notch signaling pathway, has been extensively studied during biliary and cardiac development. However, the role of JAGGED1 during craniofacial development is poorly understood. Patients with Alagille syndrome have midface hypoplasia giving them a characteristic ‘inverted V’ facial appearance. This study design determines the requirement of Jagged1 in the cranial neural crest (CNC) cells, which encompass the majority of mesenchyme present during craniofacial development. Furthermore, with this approach, we identify the autonomous and non-autonomous requirement of Jagged1 in a cell lineage-specific approach during midface development. Deleting Jagged1 in the CNC using Wnt1-cre; Jag1 Flox/Flox recapitulated the midfacial hypoplasia phenotype of Alagille syndrome. The Wnt1-cre; Jag1 Flox/Flox mice die at postnatal day 30 due to inability to masticate owing to jaw misalignment and poor occlusion. The etiology of midfacial hypoplasia in the Wnt1-cre; Jag1 Flox/Flox mice was a consequence of reduced cellular proliferation in the midface, aberrant vasculogenesis with decreased productive vessel branching and reduced extracellular matrix by hyaluronic acid staining, all of which are associated with midface anomalies and aberrant craniofacial growth. Deletion of Notch1 from the CNC using Wnt1-cre; Notch1 F/F mice did not recapitulate the midface hypoplasia of Alagille syndrome. These data demonstrate the requirement of Jagged1, but not Notch1, within the midfacial CNC population during development. Future studies will investigate the mechanism in which Jagged1 acts in a cell autonomous and cell non-autonomous manner.

Concepts: Gene, Liver, Syndromes, Alagille syndrome, JAG1, NOTCH2, Recap, Recapitulation