Category: H

Hermansky-Pudlak syndrome (HPS), which was first described in 1959 and is named after its discoverers, is characterized by a rare form of albinism that is associated with low visual acuity, bruising and prolonged bleeding, lung fibrosis, and occasionally inflammatory bowel disease and reduced kidney function (National Institute of Child Health and Development [NICHD], 2002). A…

Hereditary spastic paraplegia (HSP; also known as hereditary spastic paraparesis, Strumpell disease, Striimpell- Lorrain disease, hereditary Charcot disease, hereditary progressive spastic paraplegia, and French settlement disease) is a label used to represent a group of inherited degenerative spinal cord disorders characterized by a slow, gradual, progressive weakness and spasticity (stiffness) of the legs.  

Hemophilia is a bleeding disorder in which there is a deficiency of selected proteins in the body’s blood-clotting system. “Clotting is the process by which your blood changes from a liquid to a solid state in order to stop bleeding”. There are three main types of hemophilia in which a different clotting factor is missing…

Hemophilia is a sex-linked inherited disorder in which the individual lacks the necessary blood-clotting factors to stop bleeding. The condition is transmitted via the X chromosome, but it is believed that some individuals are affected by hemophilia due to mutation of the genes on that chromosome. There are two forms of hemophilia: Type A (with…

Hemispherectomy is a surgical procedure involving the removal of “a cerebral hemisphere, including the frontal, temporal, parietal, and occipital lobes while leaving intact parts of the thalamus and basal ganglia”. A hemispherectomy may be performed as a treatment for severe seizure disorders, fatal tumors, hemiplegia, and Rasmussen encephalitis. The procedure is usually reserved as a…

Hecht syndrome (HS) is a rare, hereditary disorder of muscle development and mechanics. The first case report appeared in 1968. Subsequently, several affected individuals in an extended family group were described.  

Hearing impaired is a term used to describe individuals who have a significant hearing loss. Hearing loss can be classified into four types: conductive, sensorineural, mixed, or central. Sensorineural loss, or nerve deafness, is the most common hearing impairment (Better Hearing Institute, 1999). Hearing impairment can also be defined by severity of loss. A decibel…

Hay-Wells syndrome (H-WS) is a disorder of ectodermal dysplasia (malformation of skin, hair, nails, and teeth) in association with cleft lip, cleft palate, or both, and string-like, fibrous band between the upper and lower eyelids (ankyloblepharon). H-WS is a congenital, hereditary condition with the previously listed abnormalities present at birth.  

Hand-foot-mouth disease is a childhood illness caused by various members of the enterovirus family. The most common cause is Coxsackie A16. Other common causes include other strains of Coxsackie A and enterovirus 71 (Ministry of Health, 2000). The virus is commonly recognized by a blister-like rash that appears most commonly on the hands, feet, and…

Hallucinogens, also known as psychedelics, cause the distortion of a person’s senses, emotions, perceptions, thinking, and self-awareness. These distortions are known as hallucinations. For example, vision can be perceived as sound, and smell can be perceived as vision. Pseudohallucinations are also possible; in these, the user knows that the perceptions are not reality and are…