The classical triad of symptoms that defines<unk>  includes certain heart defects, hypoplasia (underdevelopment) of the cerebellum, and cranial dysmorphisms, which can take various forms. The heart defects and cranial dysmorphisms are heterogeneous in individuals who are all classed as having Ritscher-Schinzel syndrome. Heart defects commonly seen with Ritscher-Schinzel syndrome are associated with the endocardial cushion and are the most important factor in determining a diagnosis. The mitral valve and tricuspid valve of the heart can be malformed, the atrioventricular canal can be complete instead of developing into the interatrial septum and interventricular septum, and conotruncal heart defects, which include tetralogy of Fallot, double outlet right ventricle, transposition of the great vessels, and hypoplastic left heart syndrome. Aortic stenosis and pulmonary stenosis have also been associated with<unk> . The cranial dysmorphisms associated with<unk>  are heterogeneous and include a degree of macrocephaly, a large anterior fontanel, a particularly prominent occiput and forehead, ocular hypertelorism (wide-set eyes), slanted palpebral fissures, cleft palate, a depressed nasal bridge, cleft palate with associated bifid uvula, low-set ears, micrognathia (an abnormally small jaw), brachycephaly (flattened head), and ocular coloboma. Low-set ears are the most common cranial dysmorphism seen in<unk> , and ocular coloboma is the least common of the non-concurrent symptoms (cleft lip co-occurring with cleft palate is the least common). Cranial dysplasias associated with<unk>  are also reflected in the brain. Besides the cerebellar hypoplasia, cysts are commonly found in the posterior cranial fossa, the ventricles and the cisterna magna are dilated/enlarged, and Dandy-Walker malformation is present. These are reflected in the developmental delays typical of the disease. 75% of children with<unk>  have Dandy-Walker malformation and hydrocephalus. Signs and symptoms in other body systems are also associated with<unk> . In the skeletal system, ribs may be absent, and hemivertebrae, syndactyly (fusion of fingers together), and clinodactyly (curvature of the fifth finger) may be present. In the GI and genitourinary systems, anal atresia, hypospadia (misplaced urethra), and hydronephrosis may exist. Adrenal hypoplasia and growth hormone deficiency are associated endocrine consequences of Ritscher-Schinzel syndrome. Some immunodeficiency has also been reported in connection with<unk> . Many children with the disorder die as infants due to severe congenital heart disease. The proband of Ritscher and Schinzel's original study was still alive at the age of 21. A fetus with<unk>  may have an umbilical cord with one umbilical artery instead of two.
3C syndrome
CAMFAK syndrome
3-M syndrome
TEMPI syndrome
TAN syndrome
WAGR syndrome
RIDDLE syndrome
VEXAS syndrome