Category: D

Duane syndrome is a congenital disorder that limits range of eye movement. Sometimes called Duane retraction syndrome, this disorder affects one or both eyes, causing a retraction of the eyeball when it attempts to turn in a particular direction. Eye movement is limited in one of three ways: outward toward the ear (Type 1), inward…

Distal arthrogryposis syndrome (DAS) is a hereditary, congenital neuromuscular disorder. It is distinguished by multiple contractures of the fingers, hands, and feet. Less frequently there may be hip, knee, or shoulder involvement. Two distinct clinical forms exist.  

DiGeorge syndrome (DGS) is a set of phenotypic abnormalities including T cell-mediated immune deficits, thymic aplasia, congenital hypoparathyroidism, mild facial anomalies, developmental delay, and congenital heart defects. The syndrome was initially described in 1965. Simultaneously, other overlapping syndromes were identified, including velocardiofacial syndrome (VCFS). Ultimately, secondary to an overlap of clinical symptoms, as well as…

De Sanctis-Cacchione (DSC) syndrome is a very rare, more severe variant of xerodosa pigmentosum (XP) that also includes mental retardation, numerous neurological abnormalities, dwarfism, and hypogonadism. De Sanctis–Cacchione syndrome is an inheritable disorder that is passed down as an autosomal recessive trait. This condition exhibits unique features including xeroderma pigmentosum, which is an extreme sensitivity…

Early auditory deprivation occurs when auditory stimuli during early childhood are not sufficient for adequate development of the auditory system. Variations in quantity, quality, or timing of exposure can lead to atypical development. In general, the more severe or complete and early the deprivation, the more detrimental the effects. The implications of such deprivation are…

Denys-Drash syndrome, also known as Drash syndrome, is the combination of Wilms tumor (a malignant cancerous tumor of the kidney), pseudohermaphroditism (unambiguous gonadal sex with ambiguous external genitalia), and nephrotic syndrome (the deterioration of the kidney’s renal tubular epithelium). This syndrome is characterized as a rare genetic disorder caused by the mutation of the Wilms…

Dementia refers to a global cognitive decline that impacts more than one component of cognitive functioning and involves a memory impairment. The term decline indicates deterioration in cognitive functioning from a previous higher level of functioning (American Psychiatric Association [APA], 2000). The etiology of dementia may be traced to a general medical condition, persistent effects…

De Barsy syndrome is a heritable disorder characterized by progeria, or accelerated aging, due to loss of dermal elasticity and primarily facial features that give the individual a characteristic aged appearance. In addition to the progeroid aspect, other defining characteristics of De Barsy syndrome include involuntary movements and posturing of the arms and legs (athetosis),…

Darier disease is a skin disorder in which a red rash appears on parts of the body, particularly the forehead, ears, neck, chest, groin, and back. This rash often has a foul odor and is accompanied by weakening of the fingernails causing V-shaped indentations. The rash may also itch. Darier disease is not contagious. Darier…

Degenerative motor diseases refers to a group of central nervous system (CNS) disorders that have an insidious onset and lead to progressive deterioration in motor functioning. These diseases are often transmitted genetically; however, infectious agents have been linked to some conditions (e.g., spongiform encephalopathatic virus causing Cruetzfelt-Jakob disease). Not all movement disorders are progressive; in…