Torsade-de-pointes (TdP) syndrome with short coupling interval is a very rare variant of Torsade de pointes, a polymorphic ventricular tachycardia, which is characterized by a short coupling interval of the first TdP beat on electrocardiogram in the absence of any structural heart disease.
Description Torsade de pointes is characterized by an electrocardiographic (ECG) pattern of nonuniform but still-organized electrical activity with progressive changes in morphology, amplitude, and polarity of the QRS complexes, the peaks of which twist around the isoelectric baseline before ending spontaneously. In classic torsade de pointes, the coupling interval of the first beat is long (see LQT1, 192500), whereas in this short-coupled variant, the coupling interval of the first beat is very short (summary by Leenhardt et al., 1994). Clinical Features Leenhardt et al. (1994) described 14 patients, 7 men and 7 women (mean age, 34.6 years) without structural heart disease, who were referred for the evaluation and treatment of severe syncope; each had at least 1 documented episode of ventricular tachyarrhythmia showing the electrical characteristics of torsade de pointes. Syncope was provoked by emotion in 2 patients and by exercise in 1 patient. In 10 of the 14 patients, degeneration of torsade de pointes into ventricular fibrillation was documented, and the patients required resuscitation; 4 patients had a family history of sudden death.
A number sign (#) is used with this entry because autosomal dominant mental retardation syndrome-20 (MRD20) is caused by heterozygous mutation in the MEF2C gene (600662) on chromosome 5q14.3. ... These 2 genes are involved in Rett or Rett syndrome-like phenotypes (312750 and 300672, respectively), which share some features with MRD20.
Hirschsprung disease-deafness-polydactyly syndrome is an extremely rare malformative association, described in only two siblings to date, characterized by Hirschsprung disease (defined by the presence of an aganglionic segment of variable extent in the terminal part of the colon that leads to symptoms of intestinal obstruction, including constipation and abdominal distension), polydactyly of hands and/or feet, unilateral renal agenesis, hypertelorism and congenital deafness.
Santos et al. (1988) described a brother and sister, offspring of first-cousin parents, with a syndrome of Hirschsprung disease, polydactyly, unilateral renal agenesis, hypertelorism, and congenital deafness.
Spastic paraplegia-Paget disease of bone syndrome is an extremely rare, complex form of hereditary spastic paraplegia characterized by a slowly progressive spastic paraplegia (with increased muscle tone, decreased strength in the anterior tibial muscles and hyperreflexia in the lower extremities with Babinski sign) presenting in adulthood, associated with Paget disease of the bone.
Microcephaly-complex motor and sensory axonal neuropathy syndrome is an extremely rare subtype of hereditary motor and sensory neuropathy characterized by severe, rapidly-progressing, distal, symmetric polyneuropathy and microcephaly (which can be evident in utero) with intact cognition.
Lymphedema-atrial septal defects-facial changes syndrome is characterised by congenital lymphoedema of the lower limbs, atrial septal defect and a characteristic facies (a round face with a prominent forehead, a flat nasal bridge with a broad nasal tip, epicanthal folds, a thin upper lip and a cleft chin).
Irons et al. (1996) considered this complex to be a previously unknown syndrome with autosomal recessive inheritance. ... Analysis of several genes known to be involved in syndromes with lymphedema detected no pathogenic mutations.
Metaphyseal dysostosis-intellectual disability-conductive deafness syndrome is characterised by metaphyseal dysplasia, short-limb dwarfism, mild intellectual deficit and conductive hearing loss, associated with repeated episodes of otitis media in childhood.
Rimoin and McAlister (1971) reported 3 brothers, born of consanguineous Sicilian parents, with an apparently autosomal recessive syndrome of metaphyseal dysplasia, short-limb dwarfism that was more apparent in the lower limbs, mild mental retardation, and conductive hearing loss.
A rare, genetic, syndromic intellectual disability disorder characterized by mild to moderate intellectual disability, facial dysmorphism (including a long face, deep-set eyes, narrow-based, broad nose with nostril colobomata, mandibular prognathism), hypergonadotrophic hypogonadism, eunuchoid habitus, diabetes mellitus type 1, and epilepsy.
Fryns et al. (1990) described a family in which 4 (3 males and 1 female) of 12 children from healthy, nonconsanguineous parents had a combination of moderate mental retardation, peculiar craniofacial dysmorphism, hypergonadotropic hypogonadism, eunuchoid habitus, diabetes mellitus, and epilepsy. All were investigated as adults. The diabetes was type I beginning in the teens. The craniofacial features included a narrow-based but broad nose with coloboma of the alae nasi, deep-set eyes, and a long face with relative mandibular prognathism. GU - Hypergonadotrophic hypogonadism Neuro - Moderate mental retardation - Seizures Metabolic - Diabetes mellitus Inheritance - Autosomal recessive Skel - Eunuchoid habitus HEENT - Craniofacial dysmorphism - Narrow-based broad nose - Coloboma of alae nasi - Deep-set eyes - Long face - Relative mandibular prognathism ▲ Close
Cleft lip/palate-intestinal malrotation-cardiopathy is a multiple congenital anomaly syndrome characterized by flat face, hypertelorism, flat occiput, upward slanting palpebral fissures, cleft palate, micrognathia, short neck, and severe congenital heart defects.
The boy was initially thought to have Simpson-Golabi-Behmel syndrome (SGBS; 312870) on the basis of macrosomia, cleft lip and palate, tongue anomaly, short broad hands, and visceromegaly with hypertrophic pancreatic islets. After the birth of the severely affected sister, SGBS seemed unlikely because that condition is X-linked. Fryns syndrome (229850) was considered unlikely because diaphragmatic hernia is found in over 90% of patients with that syndrome. Robinow syndrome (180700) was also considered, but the severity of the heart defects was considered atypical and neither patient had hemivertebrae or short arms.
A rare, genetic, syndromic intellectual disability disorder characterized by severe psychomotor development delay (without development of primary motor abilities and speech) and sever intellectual disability, associated with marfanoid habitus, joint laxity, bilateral hip luxation, hypotonia, scoliosis, and characteristic facial dysmorphism (i.e. high nasal bridge, sharp nose, short philtrum, large mouth, full lips and maxillary hypoplasia).
Dysmorphism-short stature-deafness-disorder of sex development syndrome is characterized by dysmorphism (including facial asymmetry, arched eyebrows, hypertelorism, broad and flat nasal bridge, microtia, small nose with anteverted nostrils, micrognathia), deafness, cleft palate, male pseudohermaphroditism, and growth and psychomotor retardation.
Idiopathic uveal effusion syndrome is a rare acquired eye disease characterized by uni- or bilateral abnormal fluid accumulation within the suprachoroidal space, resulting in internal choroidal elevation, in the absence of any known cause, such as decreased intraocular tension, intraocular tumor, intraocular inflammation or nanophtalmos.
Cataract-aberrant oral frenula-growth delay syndrome is characterized by cataracts and short stature associated with variable anomalies, including aberrant oral frenula, a characteristic facial appearance (posteriorly angulated ears, upslanting palpebral fissures, small nose, ptosis and epicanthal folds) cavernous hemangiomas and hernias.
Clinical Features Wellesley et al. (1991) described a mother and 2 children, a boy and a girl, with short stature, cataracts, and aberrant oral frenula. The mother was 150 cm tall (less than the 3rd centile) and had had cataracts removed in early adulthood. The boy had left ptosis with hypermetropia, and bilateral posterior polar cataracts were removed at the age of 3 years. His facial changes consisted of epicanthal folds. There were numerous aberrant frenula of the upper alveolar margin. He had a small umbilical hernia and had had bilateral inguinal herniorrhaphies.
Deafness-genital anomalies-metacarpal and metatarsal synostosis syndrome is characterised by sensorineural deafness, bilateral synostosis of the 4th and 5th metacarpals and metatarsals, genital anomalies (hypospadias in males), psychomotor delay and abnormal dermatoglyphics.
A rare genetic multiple congenital anomalies/dysmorphic syndrome characterized by the association of Pierre Robin Sequence (congenital micrognathia and glossoptosis with airway obstruction and a U-shaped cleft of the soft palate) with joint contractures and developmental delay.
A rare, X-linked syndromic intellectual disability disorder characterized by non-progressive ataxia, apraxia, variable intellectual disability and/or visuospatial, visuographic and visuoconstructive dysfunctions in male patients.
A rare genetic syndromic intellectual disability characterized by moderate to severe intellectual deficiency, language deficit (completely absent or significantly impaired speech), and distinctive facial dysmorphism (long face, straight eyebrows, and, less frequently, low-set ears and café-au-lait spots).
SETBP1 disorder is a condition that involves speech and language problems, intellectual disability, and distinctive facial features. In people with SETBP1 disorder, problems with expressive language skills (vocabulary and the production of speech) are generally more severely affected than receptive language skills (the ability to understand speech). Speech development may be limited to a few words or no speech. Affected individuals often communicate using gestures or by mimicking the expressions of others. Individuals with SETBP1 disorder have intellectual disability that can range from mild to moderate. They may also have behavioral problems, such as attention-deficit/hyperactivity disorder (ADHD) or autistic behaviors that affect communication and social interaction.
A number sign (#) is used with this entry because autosomal dominant mental retardation-29 (MRD29) is caused by heterozygous mutation in the SETBP1 gene (611060) on chromosome 18q12. Clinical Features Coe et al. (2014) reported 9 patients, including 1 reported by Rauch et al. (2012), with frameshift or nonsense mutations in SETBP1 who had a cognitive phenotype ranging from normal with impaired speech to profound intellectual disability (ID). The majority of patients had speech and motor delays, mild dysmorphic features, and behavioral difficulties. Two of the patients had seizures or EEG abnormalities. In addition, the authors reported 1 patient with a deletion encompassing the SETBP1 gene. Coe et al. (2014) also reported on 1 patient studied by Marseglia et al. (2012) and 2 patients studied by Filges et al. (2011).