Diseases

Hantavirus pulmonary syndrome

Mainly occurring in the southwestern United States, but not confined to that area, Hantavirus pulmonary syndrome is a viral disease first reported in May 1993. The syndrome, which rapidly progresses from flulike symptoms to respiratory failure and, possibly, death, is known for its high mortality. The hantavirus strain that causes disease in Asia and Europe — mainly hemorrhagic fever and renal disease — is distinctly different from the one currently described in North America.

Hard skin syndrome Parana type

A rare skin disorder characterized by rigid, thick skin that covers the whole body and affects movement. Tightness of skin over the chest and abdomen can impair breathing and death can result.

HARD syndrome

A rare genetic disorder characterized by a smooth brain surface and eye, genitourinary and other abnormalities.

Hardikar syndrome

A very rare disorder characterized by obstructive liver disease, cleft lip, cleft palate, eye and urogenital abnormalities.

Harding ataxia

A rare neurological disorder primarily involving poor balance and coordination while tendon reflexes are not affected.

Harlequin ichthyosis

Harlequin ichthyosis (Harlequin baby,Harlequin-type ichthyosis,ichthyosis congenita, Ichthyosis fetalis, keratosis diffusa fetalis, Harlequin fetus, and Ichthyosis congenita gravior), is a severe genetic skin disease, which causes the dermis to be around 10 times thicker than normal and grow at an exceptionally fast rate. At birth, the child’s whole body is encased in an ‘armour’ of thick white plates of skin, separated with deep cracks. In addition, the eyes, ears, penis, and the appendages may be abnormally contracted. Because of resultant cracked skin in locations where normal skin would fold, it is easily pregnable by bacteria and other contaminants, which can result in serious risk of fatal infection. Constant care is required to moisturise and protect the skin.

Harlequin syndrome

A rare condition characterized by flushing and sweating that occurs only on one side of the face and may occur for no apparent reason or in response to such things as heat and exercise.

Hartnup disease

A rare metabolic disorder involving an error in the transport of neutral amino acid and characterized by mental retardation, rash due to light sensitivity and cerebellar ataxia.

Hashimoto-Pritzker syndrome

A rare harmless skin disorder characterized by the accumulation of histiocytes (infection-fighting cells) in the skin which forms nodules. The condition occurs at birth or soon after and resolves spontaneously within a month.

Hashimoto’s thyroiditis

Hashimoto's thyroiditis, also known as Hashimoto’s syndrome, or chronic lymphocytic thyroiditis, is an autoimmune disease in which the thyroid gland is attacked by a variety of cell- and antibody-mediated immune processes. It was the first disease to be recognized as an autoimmune disease. It was first described by the Japanese specialist Hakaru Hashimoto in Germany in 1912.

Hawkinsinuria

Hawkinsinuria, also called 4-Alpha-hydroxyphenylpyruvate hydroxylase deficiency, is an autosomal dominant metabolic disorder affecting the metabolism of the sulfur amino acid hawkinsin. It is characterized by transient metabolic acidosis and tyrosinemia. Hawkinsinuria has an autosomal dominant pattern of inheritance. A group of disorders which have in common elevations of tyrosine in the blood and urine secondary to an enzyme deficiency. Type I tyrosinemia features episodic weakness, self-mutilation, hepatic necrosis, renal tubular injury, and seizures and is caused by a deficiency of the enzyme fumarylacetoacetase. Type II tyrosinemia features mental retardation, painful corneal ulcers, and keratoses of the palms and plantar surfaces and is caused by a deficiency of the enzyme TYROSINE TRANSAMINASE. Type III tyrosinemia features mental retardation and is caused by a deficiency of the enzyme 4-HYDROXYPHENYLPYRUVATE DIOXYGENASE.

Hay Wells syndrome recessive type

A rare recessively inherited genetic disorder characterized by ankyloblepharon, ectodermal dysplasia, and cleft lip and/or cleft palate. The recessive form of this condition is distinguished by the presence at birth of adhesions between the upper and lower jaws.

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).