Diseases

Hay-Wells syndrome

Hay-Wells syndrome is a form of ectodermal dysplasia, a group of about 150 conditions characterized by abnormal development of ectodermal tissues including the skin, hair, nails, teeth, and sweat glands.

Among the most common features are missing patches of skin (erosions). In affected infants, skin erosions most commonly occur on the scalp. They tend to recur throughout childhood and into adulthood, frequently affecting the scalp, neck, hands, and feet. The skin erosions range from mild to severe and can lead to infection, scarring, and hair loss. Other ectodermal abnormalities in AEC syndrome include changes in skin coloring; brittle, sparse, or missing hair; misshapen or absent fingernails and toenails; and malformed or missing teeth. Affected individuals also report increased sensitivity to heat and a reduced ability to sweat.

Many infants with AEC syndrome are born with an eyelid condition known as ankyloblepharon filiforme adnatum, in which strands of tissue partially or completely fuse the upper and lower eyelids. Most people with AEC syndrome are also born with an opening in the roof of the mouth (a cleft palate), a split in the lip (a cleft lip), or both. Cleft lip or cleft palate can make it difficult for affected infants to suck, so these infants often have trouble feeding and do not grow and gain weight at the expected rate (failure to thrive).

Additional features of AEC syndrome can include limb abnormalities, most commonly fused fingers and toes (syndactyly). Less often, affected individuals have permanently bent fingers and toes (camptodactyly) or a deep split in the hands or feet with missing fingers or toes and fusion of the remaining digits (ectrodactyly). Hearing loss is common, occurring in more than 90 percent of children with AEC syndrome. Some affected individuals have distinctive facial features, such as small jaws that cannot open fully and a narrow space between the upper lip and nose (philtrum). Other signs and symptoms can include the opening of the urethra on the underside of the penis (hypospadias) in affected males, digestive problems, absent tear duct openings in the eyes, and chronic sinus or ear infections.

A condition known as Rapp-Hodgkin syndrome has signs and symptoms that overlap considerably with those of AEC syndrome. These two syndromes were classified as separate disorders until it was discovered that they both result from mutations in the same part of the same gene. Most researchers now consider Rapp-Hodgkin syndrome and AEC syndrome to be part of the same disease spectrum.

Heart tumor

A tumor is any type of abnormal growth, whether cancerous (malignant) or noncancerous (benign). Tumors that originate in the heart are called primary tumors. They may develop in any of the heart tissues and may be cancerous or noncancerous. Primary heart tumors are rare, occurring in fewer than 1 of 2,000 people. In adults, about half of noncancerous primary heart tumors are myxomas. Myxomas usually develop in the heart's left upper chamber (atrium). They may develop from embryonic cells located in the inner layer (lining) of the heart's wall.

Heavy metal poisoning

The body does not handle most heavy metals well, and excess levels are poisonous. Lead poisoning is well-known, but also potentially poisonous are mercury, thallium, arsenic, and even iron (e.g. iron tablets).

HEC syndrome

A very rare syndrome characterized mainly by excess fluid inside the skull, cataracts and thickening of the heart.

Hecht Scott syndrome

A very rare syndrome characterized mainly by heart anomaly and leg and hand malformations involving missing bones.

Hecht syndrome

A rare genetic disorder characterized by the inability to open the mouth due to short muscles as well as hand movement abnormalities also due to shortened muscles.

HELLP syndrome

HELLP syndrome is a life-threatening obstetric complication usually considered to be a variant or complication of pre-eclampsia. Both conditions usually occur during the later stages of pregnancy, or sometimes after childbirth. "HELLP" is an abbreviation of the three main features of the syndrome:

  • Hemolysis
  • Elevated Liver enzymes
  • Low Platelet count

Helminthiasis

Infection of the human body with a parasitic worm such as roundworms and pinworms. The worms usually only involve the intestinal tract but sometimes they may invade other organs. The type and severity of symptoms is determined by the type of worm and the part of the body infected.

HEM dysplasia

A rare disorder characterized by hydrops, dwarfism and abnormal bone calcification. The condition generally results in fetal death.

Hemangioblastoma

Hemangioblastoma of the central nervous system is a benign tumor (WHO grade I) that is typically cystic and can occur throughout the central nervous system. It is a tumor composed of hemangioblasts, a type of stem cell that normally give rise to blood vessels or blood cells. Its name breaks down to Greek roots as follows: Haema (blood), angeion (vessel), blastos (embryonic), oma (tumor).

Hemangioendothelioma

Hemangioendothelioma is used to describe a group of vascular neoplasms that may be considered benign or malignant in their activity.

Hemangioma thrombocytopenia syndrome

A rare condition characterized by a spreading congenital hemangioma (collection of abnormal blood vessels) usually on the skin as well as blood clotting problems.

Hemangioma- capillary infantile

A dull red, firm, dome-shaped hemangioma, sharply demarcated from surrounding skin, usually located on the head and neck, which grows rapidly and generally undergoes regression and involution without scarring. It is caused by proliferation of immature capillary vessels in active stroma, and is usually present at birth or occurs within the first two or three months of life.

Hemangiopericytoma

Hemangiopericytomas are rare vascular tumors that arise from pericytes, which are cells that are associated with capillary walls. These tumors can originate anywhere in the body there are capillaries, which is virtually everywhere. The most common locations reported are the lower extremities, pelvic area, head, and neck. They occur in all ages and equally in both sexes. They can be either benign or malignant, and can metastasize, with the most common sites being the lungs and bones.

Hemeralopia- familial

A rare familial disorder where a person can only see when the light is faint or absent. Sufferers are unable to see in bright light and thus daytime vision is poor but nighttime vision is good.

Hemi 3 syndrome

A very rare syndrome where parts of the body undergo excessive growth give the body an asymmetrical appearance.

Hemifacial hyperplasia strabismus

Hemifacial hyperplasia strabismus is a rare inherited condition characterized mainly by abnormal, asymmetrical facial bone growth and eye problems in some cases.

Hemimegalencephaly

Hemimegalencephaly is a rare neurological condition in which one-half of the brain, or one side of the brain, is abnormally larger than the other. As a consequence of this imbalance, the unusual and enlarged brain tissue causes frequent seizures, usually followed with mental retardation. Hemimegalencephaly may occur as an isolated finding in an infant or it may be associated with other syndromes.

Hemiplegia

Hemiplegia is a condition in which one-half of a patient's body is paralyzed. Hemiplegia is more severe than hemiparesis, wherein one half of the body is weakened but not paralysed