Achondroplasia is the most frequent form of short-limb dwarfism. Affected individuals exhibit short stature caused by rhizomelic shortening of the limbs, characteristic facies with frontal bossing and midface hypoplasia, exaggerated lumbar lordosis, limitation of elbow extension, genu varum, and trident hand
ACTH-independent macronodular adrenal hyperplasia (AIMAH) is an endogenous form of adrenal Cushing syndrome characterized by multiple bilateral adrenocortical nodules that cause a striking enlargement of the adrenal glands. Although some familial cases have been reported, the vast majority of AIMAH cases are sporadic. Patients typically present in the fifth and sixth decades of life, approximately 10 years later than most patients with other causes of Cushing syndrome.
Apert syndrome is a congenital disorder characterized primarily by craniosynostosis, midface hypoplasia, and syndactyly of the hands and feet with a tendency to fusion of bony structures. Most cases are sporadic, but autosomal dominant inheritance has been reported
Atelosteogenesis is a lethal chondrodysplasia characterized by distal hypoplasia of the humeri and femurs, hypoplasia of the midthoracic spine, occasionally complete lack of ossification of single hand bones, and the finding in cartilage of multiple degenerated chondrocytes encapsulated in fibrous tissue.
Beare-Stevenson cutis gyrata syndrome is a genetic disorder characterized by skin abnormalities and the premature fusion of certain bones of the skull (craniosynostosis). This early fusion prevents the skull from growing normally and affects the shape of the head and face.
Camptodactyly is a medical condition that causes one or more fingers to be permanently bent. It involves fixed flexion deformity of the proximal interphalangeal joints. The fifth finger is always affected. Camptodactyly can be caused by a genetic disorder. In that case, it is an autosomal dominant trait that is known for its incomplete genetic expressivity. This means that when a person has the genes for it, the condition may appear in both hands, one, or neither.
Crouzon syndrome is an autosomal dominant disorder characterized by craniosynostosis causing secondary alterations of the facial bones and facial structure. Common features include hypertelorism, exophthalmos and external strabismus, parrot-beaked nose, short upper lip, hypoplastic maxilla, and a relative mandibular prognathism.
Dandy–Walker syndrome (DWS) is a rare group of congenital human brain malformations. There are three subtypes which affect multiple organs to varying degrees, but the fundamental abnormalities involve the cerebellum which controls muscle coordination.
De La Chapelle Dysplasia is a lethal chondrodysplasia characterized by distal hypoplasia of the humeri and femurs, hypoplasia of the midthoracic spine, occasionally complete lack of ossification of single hand bones, and the finding in cartilage of multiple degenerated chondrocytes encapsulated in fibrous tissue.
Diastrophic dysplasia is a disorder of cartilage and bone development. Affected individuals have short stature with very short arms and legs. Most also have early-onset joint pain (osteoarthritis) and joint deformities called contractures, which restrict movement. These joint problems often make it difficult to walk and tend to worsen with age. Additional features of diastrophic dysplasia include an inward- and upward-turning foot (clubfoot), progressive abnormal curvature of the spine, and unusually positioned thumbs (hitchhiker thumbs). About half of infants with diastrophic dysplasia are born with an opening in the roof of the mouth (a cleft palate). Swelling of the external ears is also common in newborns and can lead to thickened, deformed ears.
Hypochondroplasia is a autosomal dominant disorder characterized by short-limbed dwarfism, lumbar lordosis, short and broad bones, and caudad narrowing of the interpediculate distance of the lumbar spine. It shows some resemblance to achondroplasia, but is much milder and can be distinguished on clinical and radiographic grounds.
Hypogonadotropic hypogonadism (HH), also known as secondary or central hypogonadism, as well as gonadotropin-releasing hormone deficiency or gonadotropin deficiency (GD), is a condition which is characterized by hypogonadism due to an impaired secretion of gonadotropins, including follicle-stimulating hormone (FSH) and luteinizing hormone (LH), by the pituitary gland in the brain, and in turn decreased gonadotropin levels and a resultant lack of sex steroid production.
Infectious mononucleosis (IM, mono), also known as glandular fever, is an infection usually caused by the Epstein–Barr virus (EBV). Most people are infected by the virus as children, when the disease produces few or no symptoms. In young adults, the disease often results in fever, sore throat, enlarged lymph nodes in the neck, and tiredness. Most people get better in two to four weeks; however, feeling tired may last for months.The liver or spleen may also become swollen, and in less than one percent of cases splenic rupture may occur.
Intellectual disability is a disability characterized by significant limitations in both intellectual functioning and in adaptive behavior, which covers many everyday social and practical skills. This disability originates before the age of 18.
Jackson-Weiss syndrome is a genetic disorder characterized by foot abnormalities and the premature fusion of certain skull bones (craniosynostosis). This early fusion prevents the skull from growing normally and affects the shape of the head and face.
Kallmann syndrome is a rare genetic hormonal condition that is characterized by a failure to start or a failure to complete puberty. It is also accompanied by a lack of sense of smell (anosmia) or a highly reduced sense of smell (hyposmia). The condition can occur in both males and females but is more commonly diagnosed in males. Left untreated, patients with Kallmann syndrome will almost invariably be infertile. Kallmann syndrome is a form of hypogonadotropic hypogonadism (HH).
Lacrimoauriculodentodigital syndrome is a multiple congenital anomaly disorder mainly affecting lacrimal glands and ducts, salivary glands and ducts, ears, teeth, and distal limb segments.
Lissencephaly is a developmental disorder characterized by structural brain anomalies, early-onset intractable seizures, severe psychomotor retardation, and ambiguous genitalia.
The disorder is characterized clinically by the classic triad of polyostotic fibrous dysplasia (POFD), cafe-au-lait skin pigmentation, and peripheral precocious puberty. However, the disorder is clinically heterogeneous and can include various other endocrinologic anomalies such as thyrotoxicosis, pituitary gigantism, and Cushing syndrome.
Muenke syndrome is an autosomal dominant disorder characterized by uni- or bicoronal synostosis, macrocephaly, midfacial hypoplasia, and developmental delay. Other more variable features include thimble-shaped middle phalanges, brachydactyly, carpal/tarsal fusion, and deafness. The phenotype is variable and can range from no detectable clinical manifestations to complex findings
Individuals with trigonocephaly have a keel-shaped forehead with wide biparietal diameter, resulting in a triangular shape of the head. Trigonocephaly results from premature closure of the metopic sutures and usually occurs sporadically.
Osteoglophonic dysplasia is a condition characterized by abnormal bone growth that leads to severe head and face (craniofacial) abnormalities, dwarfism, and other features.
Pfeiffer syndrome is an autosomal dominant craniosynostosis syndrome with characteristic anomalies of the hands and feet. Three clinical subtypes, which have important diagnostic and prognostic implications, have been identified (Cohen, 1993). Type 1, the classic syndrome, is compatible with life and consists of craniosynostosis, midface deficiency, broad thumbs, broad great toes, brachydactyly, and variable syndactyly. Type 2 consists of cloverleaf skull with Pfeiffer hands and feet, together with ankylosis of the elbows. Type 3 is similar to type 2 but without cloverleaf skull. Ocular proptosis is severe, and the anterior cranial base is markedly short. Various visceral malformations have been found in association with type 3. Early demise is characteristic of types 2 and 3.
Progressive osseous heteroplasia is caused by certain mutations that affect the paternal copy of the gene. These mutations disrupt the function of the G protein and impair its ability to regulate osteogenesis. Impaired regulation of osteogenesis results in the ectopic production of bony tissue in the skin and muscles seen in progressive osseous heteroplasia.
In its rare complete form, 'prune belly' syndrome comprises megacystis (massively enlarged bladder) with disorganized detrusor muscle, cryptorchidism, and thin abdominal musculature with overlying lax skin.
Pseudohypoparathyroidism is a term applied to a heterogeneous group of disorders whose common feature is end-organ resistance to parathyroid hormone (PTH; 168450). In addition to PTH resistance, PHP Ia is characterized by resistance to other hormones, including thyroid-stimulating hormone (TSH; see TSHB, 188540) and gonadotropins. PHP Ia is associated with a constellation of clinical features referred to as Albright hereditary osteodystrophy (AHO), which includes short stature, obesity, round facies, subcutaneous ossifications, brachydactyly, and other skeletal anomalies. Some patients have mental retardation.
Patients with pseudopseudohypoparathyroidism do not show resistance to parathyroid hormone (PTH) or other hormones, as is the case with PHP1A, but do manifest the constellation of clinical features referred to as Albright hereditary osteodystrophy (AHO), which includes short stature, obesity, round facies, subcutaneous ossifications, brachydactyly, and other skeletal anomalies. Some patients have mental retardation.
Multiple epiphyseal dysplasia is a disorder of cartilage and bone development primarily affecting the ends of the long bones in the arms and legs.
Saddan Dysplasia (severe achondroplasia with developmental delay and acanthosis nigricans) is a rare disorder of bone growth characterized by skeletal, brain, and skin abnormalities.
Seathre-Chotzen Syndrome is an autosomal dominant disorder characterized by uni- or bicoronal synostosis, macrocephaly, midfacial hypoplasia, and developmental delay. Other more variable features include thimble-shaped middle phalanges, brachydactyly, carpal/tarsal fusion, and deafness. The phenotype is variable and can range from no detectable clinical manifestations to complex findings.
Tetra-amelia syndrome is a very rare disorder characterized by the absence of all four limbs. ("Tetra" is the Greek word for "four," and "amelia" refers to the failure of an arm or leg to develop before birth.) This syndrome can also cause severe malformations of other parts of the body, including the face and head, heart, nervous system, skeleton, and genitalia. The lungs are underdeveloped in many cases, which makes breathing difficult or impossible. Because children with tetra-amelia syndrome have such serious medical problems, most are stillborn or die shortly after birth.
Thanatophoric dysplasia is a severe skeletal disorder characterized by extremely short limbs and folds of extra (redundant) skin on the arms and legs. Other features of this condition include a narrow chest, short ribs, underdeveloped lungs, and an enlarged head with a large forehead and prominent, wide-spaced eyes.