MedGen

A sudden movement downward, usually resulting in injury. [from NCI]

Lethal multiple pterygium syndrome has many of the same signs and symptoms as the Escobar type. In addition, affected fetuses may develop a buildup of excess fluid in the body (hydrops fetalis) or a fluid-filled sac typically found on the back of the neck (cystic hygroma). Individuals with this type have severe arthrogryposis. Lethal multiple pterygium syndrome is associated with abnormalities such as underdevelopment (hypoplasia) of the heart, lung, or brain; twisting of the intestines (intestinal malrotation); kidney abnormalities; an opening in the roof of the mouth (a cleft palate); and an unusually small head size (microcephaly). Affected individuals may also develop a hole in the muscle that separates the abdomen from the chest cavity (the diaphragm), a condition called a congenital diaphragmatic hernia. Lethal multiple pterygium syndrome is typically fatal in the second or third trimester of pregnancy.

In people with multiple pterygium syndrome, Escobar type, the webbing typically affects the skin of the neck, fingers, forearms, inner thighs, and backs of the knee. People with this type may also have arthrogryposis. A side-to-side curvature of the spine (scoliosis) is sometimes seen. Affected individuals may also have respiratory distress at birth due to underdeveloped lungs (lung hypoplasia). People with multiple pterygium syndrome, Escobar type usually have distinctive facial features including droopy eyelids (ptosis), outside corners of the eyes that point downward (downslanting palpebral fissures), skin folds covering the inner corner of the eyes (epicanthal folds), a small jaw, and low-set ears. Males with this condition can have undescended testes (cryptorchidism). This condition does not worsen after birth, and affected individuals typically do not have muscle weakness later in life.

The two forms of multiple pterygium syndrome are differentiated by the severity of their symptoms. Multiple pterygium syndrome, Escobar type (sometimes referred to as Escobar syndrome) is the milder of the two types. Lethal multiple pterygium syndrome is fatal before birth or very soon after birth.

Multiple pterygium syndrome is a condition that is evident before birth with webbing of the skin (pterygium) at the joints and a lack of muscle movement (akinesia) before birth. Akinesia frequently results in muscle weakness and joint deformities called contractures that restrict the movement of joints (arthrogryposis). As a result, multiple pterygium syndrome can lead to further problems with movement such as arms and legs that cannot fully extend. [from MedlinePlus Genetics]

An eyebrow that extends laterally beyond the orbital rim rather than turning gently downward at that location. [from HPO]

Downward movement of the trachea during inspiration due to downward traction on the tracheobronchial tree. [from HPO]

In primary position, the eyes drift slowly downward and then spontaneously beat upward. Upward gaze accentuates the nystagmus. The associated oscillopsias are often very irritating, but the symptoms are usually transient. [from HPO]

Downbeat nystagmus is a type of fixation nystagmus with the fast phase beating in a downward direction. It generally increases when looking to the side and down and when lying prone. [from HPO]

Carpenter syndrome is a condition characterized by the premature fusion of certain skull bones (craniosynostosis), abnormalities of the fingers and toes, and other developmental problems.

Craniosynostosis prevents the skull from growing normally, frequently giving the head a pointed appearance (acrocephaly). In severely affected individuals, the abnormal fusion of the skull bones results in a deformity called a cloverleaf skull. Craniosynostosis can cause differences between the two sides of the head and face (craniofacial asymmetry). Early fusion of the skull bones can affect the development of the brain and lead to increased pressure within the skull (intracranial pressure). Premature fusion of the skull bones can cause several characteristic facial features in people with Carpenter syndrome. Distinctive facial features may include a flat nasal bridge, outside corners of the eyes that point downward (down-slanting palpebral fissures), low-set and abnormally shaped ears, underdeveloped upper and lower jaws, and abnormal eye shape. Some affected individuals also have dental abnormalities including small primary (baby) teeth. Vision problems also frequently occur.

Abnormalities of the fingers and toes include fusion of the skin between two or more fingers or toes (cutaneous syndactyly), unusually short fingers or toes (brachydactyly), or extra fingers or toes (polydactyly). In Carpenter syndrome, cutaneous syndactyly is most common between the third (middle) and fourth (ring) fingers, and polydactyly frequently occurs next to the big or second toe or the fifth (pinky) finger.

People with Carpenter syndrome often have intellectual disability, which can range from mild to profound. However, some individuals with this condition have normal intelligence. The cause of intellectual disability is unknown, as the severity of craniosynostosis does not appear to be related to the severity of intellectual disability.

Other features of Carpenter syndrome include obesity that begins in childhood, a soft out-pouching around the belly-button (umbilical hernia), hearing loss, and heart defects. Additional skeletal abnormalities such as deformed hips, a rounded upper back that also curves to the side (kyphoscoliosis), and knees that are angled inward (genu valgum) frequently occur. Nearly all affected males have genital abnormalities, most frequently undescended testes (cryptorchidism).

The signs and symptoms of Carpenter syndrome are similar to another genetic condition called Greig cephalopolysyndactyly syndrome. The overlapping features, which include craniosynostosis, polydactyly, and heart abnormalities, can cause these two conditions to be misdiagnosed; genetic testing is often required for an accurate diagnosis.

A few people with Carpenter syndrome have organs or tissues within their chest and abdomen that are in mirror-image reversed positions. This abnormal placement may affect several internal organs (situs inversus); just the heart (dextrocardia), placing the heart on the right side of the body instead of on the left; or only the major (great) arteries of the heart, altering blood flow.

The signs and symptoms of this disorder vary considerably, even within the same family. The life expectancy for individuals with Carpenter syndrome is shortened but extremely variable. [from MedlinePlus Genetics]

Asymmetry observed in the face of a neonate or infant whose face appears symmetric at rest and asymmetric during crying as the mouth is pulled downward on one side while not moving on the other side. [from HPO]

An ophthalmologic sign in young children resulting from upward-gaze paresis. In this condition, the eyes appear driven downward, the sclera may be seen between the upper eyelid and the iris, and part of the lower pupil may be covered by the lower eyelid. [from HPO]

A shape created by an acute downward arching of the upper eyelid and upward arching of the lower eyelid, toward the medial canthus, which gives the outline of the palpebral fissures the configuration of an almond. Thus, the maximum distance between the fissures is offset from, and medial to, the center point. [from HPO]

The physical features of FG syndrome include weak muscle tone (hypotonia), broad thumbs, and wide first (big) toes. Abnormalities of the tissue connecting the left and right halves of the brain (the corpus callosum) are also common. Most affected individuals have constipation, and many have abnormalities of the anus such as an obstruction of the anal opening (imperforate anus). People with FG syndrome also tend to have a distinctive facial appearance including small, underdeveloped ears; a tall, prominent forehead; and outside corners of the eyes that point downward (down-slanting palpebral fissures).

FG syndrome affects intelligence and behavior. Almost everyone with the condition has intellectual disability, which ranges from mild to severe. Affected individuals tend to be friendly, inquisitive, and hyperactive, with a short attention span. Compared to people with other forms of intellectual disability, their socialization and daily living skills are strong, while verbal communication and language skills tend to be weaker.

FG syndrome is a genetic condition that affects many parts of the body and occurs almost exclusively in males. "FG" represents the surname initials of the first family diagnosed with the disorder.

Additional features seen in some people with FG syndrome include widely set eyes (hypertelorism), an upswept frontal hairline, and a large head compared to body size (relative macrocephaly). Other health problems have also been reported, including heart defects, seizures, undescended testes (cryptorchidism) in males, and a soft out-pouching in the lower abdomen (an inguinal hernia). [from MedlinePlus Genetics]

Congenital fibrosis of the extraocular muscles (CFEOM) is a disorder of the nervous system that affects use of the muscles that surround the eyes (extraocular muscles). These muscles control eye movement and the direction of the eyes (for example, looking straight ahead). CFEOM impairs control of these muscles. As a result, affected individuals are unable to move their eyes normally. Most people with this condition have difficulty looking upward, and their side-to-side eye movement may also be limited. The eyes may look in different directions (strabismus). Instead of moving their eyes, affected individuals may need to turn their head to track moving objects. Additionally, most people with CFEOM have droopy eyelids (ptosis), which further limits their vision.

Researchers have identified several forms of CFEOM, designated CFEOM1, CFEOM2, CFEOM3, and Tukel syndrome (sometimes called CFEOM4). The specific problems with eye movement vary among the types, and some types are associated with additional signs and symptoms. People with CFEOM1 and CFEOM2 have only the eye problems described above. In CFEOM1, the eyes typically point downward, whereas in CFEOM2, the eyes usually turn outward.

CFEOM3 can include additional neurological problems, such as intellectual disability; difficulty with social skills; a smaller-than-normal head size (microcephaly); muscle weakness in the face; nonfunctioning vocal cords; and a set of symptoms called Kallmann syndrome, which features delayed or absent puberty and an impaired sense of smell. Some affected individuals develop pain, weakness, or a decreased ability to feel sensations in the limbs (peripheral neuropathy), which can begin in childhood or adulthood.

Brain abnormalities can also occur in people with CFEOM3. Some have abnormal development of the white matter, which is brain tissue containing nerve cell fibers (axons) that transmit nerve impulses. A particular form of CFEOM3, known as CFEOM3 with polymicrogyria, is characterized by abnormal development of the brain, in which the folds and ridges on the surface of the brain are smaller and more numerous than usual.

Tukel syndrome is characterized by missing fingers (oligodactyly) and other hand abnormalities in addition to problems with eye movement. [from MedlinePlus Genetics]

PPP2R5D-related intellectual disability is a neurological disorder characterized by moderate to severe developmental delay and intellectual disability. Affected individuals have weak muscle tone (hypotonia); delayed development of motor skills, such as sitting, standing, and walking; and delayed speech development. Recurrent seizures (epilepsy) and autism spectrum disorder, which is characterized by impaired communications and social interaction, can also occur in affected individuals. Most people with PPP2R5D-related intellectual disability have an unusually large head size (macrocephaly), and some have other unusual facial features, including a prominent forehead (frontal bossing), widely spaced eyes (hypertelorism), and eyes that slant downward (downslanting palpebral fissures). [from MedlinePlus Genetics]

Mitochondrial complex V deficiency is a shortage (deficiency) of a protein complex called complex V or a loss of its function. Complex V is found in cell structures called mitochondria, which convert the energy from food into a form that cells can use. Complex V is the last of five mitochondrial complexes that carry out a multistep process called oxidative phosphorylation, through which cells derive much of their energy.

Mitochondrial complex V deficiency can cause a wide variety of signs and symptoms affecting many organs and systems of the body, particularly the nervous system and the heart. The disorder can be life-threatening in infancy or early childhood. Affected individuals may have feeding problems, slow growth, low muscle tone (hypotonia), extreme fatigue (lethargy), and developmental delay. They tend to develop elevated levels of lactic acid in the blood (lactic acidosis), which can cause nausea, vomiting, weakness, and rapid breathing. High levels of ammonia in the blood (hyperammonemia) can also occur in affected individuals, and in some cases result in abnormal brain function (encephalopathy) and damage to other organs.

Another common feature of mitochondrial complex V deficiency is hypertrophic cardiomyopathy. This condition is characterized by thickening (hypertrophy) of the heart (cardiac) muscle that can lead to heart failure. People with mitochondrial complex V deficiency may also have a characteristic pattern of facial features, including a high forehead, curved eyebrows, outside corners of the eyes that point downward (downslanting palpebral fissures), a prominent bridge of the nose, low-set ears, thin lips, and a small chin (micrognathia).

Some people with mitochondrial complex V deficiency have groups of signs and symptoms that are classified as a specific syndrome. For example, mitochondrial complex V deficiency can cause a condition called neuropathy, ataxia, and retinitis pigmentosa (NARP). NARP causes a variety of signs and symptoms chiefly affecting the nervous system. Beginning in childhood or early adulthood, most people with NARP experience numbness, tingling, or pain in the arms and legs (sensory neuropathy); muscle weakness; and problems with balance and coordination (ataxia). Many affected individuals also have cognitive impairment and an eye disorder called retinitis pigmentosa that causes vision loss.

A condition called Leigh syndrome can also be caused by mitochondrial complex V deficiency. Leigh syndrome is characterized by progressive loss of mental and movement abilities (developmental or psychomotor regression) and typically results in death within 2 to 3 years after the onset of symptoms. Both NARP and Leigh syndrome can also have other causes. [from MedlinePlus Genetics]

Ebstein anomaly is characterized by downward displacement of variable severity of the tricuspid valve into the right ventricle. The valve leaflets may be dysplastic, and a variable portion of the proximal part of the right ventricle is in continuity with the right atrium ('atrialized'), because of the abnormally positioned tricuspid valve. The severity of this defect includes a spectrum ranging from severe disturbance in fetal and neonatal life to virtually asymptomatic survival to adult life. Associated extracardiac anomalies in the setting of chromosomal or mendelian disorders occur in about 20% of patients with Ebstein anomaly. Nonsyndromic Ebstein anomaly can occur as a sporadic or a familial defect (summary by Digilio et al., 2011). [from OMIM]

Confluent and reticulated papillomatosis is a dermatologic disorder characterized by onset in the teenage or young adult years of hyperkeratotic 1- to 2-mm papules that increase in size to 4 to 5 mm and coalesce to form a reticular pattern peripherally and a confluent pattern centrally. Early papules can be erythematous and later turn brown. Affected individuals are usually otherwise asymptomatic. The condition is distinct from acanthosis nigricans and tinea versicolor (infection with the yeast Pityrosporum), but can appear similar. Microscopic examination of skin biopsy shows epidermal undulation with hyperkeratosis, squat papillomatosis, and occasional acanthotic downward projections from the bases of the dells between papillomatous areas. Antibacterial agents such as minocycline and azithromycin are effective, perhaps due to their antiinflammatory and immunomodulatory properties (summary by Scheinfeld, 2006). [from OMIM]

Thakker-Donnai syndrome is a rare, genetic, lethal, multiple congenital anomalies/dysmorphic syndrome characterized by facial dysmorphism (including long, downward slanting palpebral fissures, hypertelorism, posteriorly rotated ears, broad nasal bridge, short nose with a bulbous tip and anteverted nares, downturned corners of the mouth) as well as vertebral (occult spina bifida, hemivertebrae), brain (ventricular dilatation, agenesis of corpus callosum), cardiac (tetralogy of Fallot, ventricular septal defect) and gastrointestinal (short esophagus with intrathoracic stomach, small intestine, spleen and pancreas, anal atresia) malformations. There have been no further descriptions in the literature since 1991. [from ORDO]

This is a postural deformity in which the foot is positioned up against the tibia. The heel (calcaneus) is positioned downward (that is, the ankle is flexed upward), and the heel is turned outward (valgus). [from HPO]

A laryngo-tracheo-esophageal cleft (LC) is a congenital malformation characterized by an abnormal, posterior, sagittal communication between the larynx and the pharynx, possibly extending downward between the trachea and the esophagus. [from ORDO]