Diseases & conditions A-Z List
Diseases & Conditions A-Z List - «H»:
Hyphema is blood in the front area of the eye.
Hyphema is usually caused by trauma to the eye. Other causes of bleeding in the front chamber of the eye include:
Blood vessel abnormality
Cancer of the eye
Severe inflammation of the iris
Bleeding in the front portion of the eye
Hypocalcemia - infants
Hypocalcemia is an abnormally low blood calcium level. This article discusses low blood calcium levels in infants.
Calcium is a salt that helps the heart and muscles work. A healthy baby usually has very careful control of blood calcium levels.
Hypocalcemia is more likely to occur in newborn...
Hypochondria is a belief that physical symptoms are signs of a serious illness, even when there is no medical evidence to support the presence of an illness.
People with hypochondria are overly focused on their physical health. They have an unrealistic fear of having a serious disease. This ...
Hypochromia means that the red blood cells have less color than normal when examined under a microscope. This usually occurs when there is not enough of the pigment that carries oxygen (hemoglobin) in the red blood cells.
The most common cause of hypochromia in the United States is iron deficiency. ...
Hypoglycemia is a condition that occurs when your blood sugar (glucose) is too low.
Blood sugar below 70 mg/dL is considered low. Blood sugars at this level can harm you.
Hypoglycemia occurs when:
Your body's sugar (glucose) is used up too quickly
Glucose is released into the bloodstream to...
Hypogonadism is when the sex glands produce little or no hormones. In men, these glands (gonads) are the testes; in women, they are the ovaries.
The cause of hypogonadism may be "primary" or "central." In primary hypogonadism, the ovaries or testes themselves do not function properly. Some c...
Hypogonadotropic hypogonadism is absent or decreased function of the male testes or the female ovaries. It is considered a form of secondary hypogonadism, which means the condition is due to a problem with the pituitary or hypothalamus gland.
See also: Hypogonadism
Hypokalemia is a lower-than-normal amount of potassium in the blood.
Potassium is needed for cells, especially nerve and muscle cells, to function properly. You get potassium through food. The kidneys remove excess potassium in the urine to keep a proper balance of the mineral in the body.
Hypokalemic periodic paralysis
Hypokalemic periodic paralysis is an inherited disorder that causes occasional episodes of muscle weakness.
It is one of a group of genetic disorders that includes hyperkalemic periodic paralysis and thyrotoxic periodic paralysis.
Hypokalemic periodic paralysis is a condition in which a pers...
Hypomagnesemia means low levels of magnesium in the blood.
Several conditions can cause hypomagnesemia, including:
High blood calcium levels
Use of certain medications including amphotericin, cisplatin, and diure...
Hyponatremia is a metabolic condition in which there is not enough sodium (salt) in the body fluids outside the cells.
Sodium is found mostly in body fluids outside the cells. It is very important for maintaining blood pressure. Sodium is also needed for nerves and muscles to work properly.
Hypophosphatemia is a low level of phosphorus in the blood.
Various conditions may cause hypophosphatemia, including:
Vitamin D deficiency
Anemia due to excess destruction of red blood cells (hemolytic anemia)
Heart muscle damage (cardiomyopathy)...
Hypopituitarism is a condition in which the pituitary gland does not produce normal amounts of some or all of its hormones.
The pituitary gland is a small structure that is located just below the brain. It is attached by a stalk to the hypothalamus, the area of the brain that controls its fu...
Hypoplastic left heart syndrome
Hypoplastic left heart syndrome occurs when parts of the left side of the heart (mitral valve, left ventricle, aortic valve, and aorta) do not develop completely. The condition is congenital (present at birth).
Hypoplastic left heart is a rare type of congenital heart disease. It is more com...
Hypospadias is a somewhat common birth (congenital) defect in which the opening of the urethra is on the underside, rather than at the end, of the penis.
See also: Epispadias
Hypospadias affects up to 4 in 1,000 newborn boys.
Some cases are passed down through families. In other cases the c...