Endocrinology Dictionary
A
ACTH (adrenocorticotropic hormone)
A hormone made in the pituitary gland that tells the adrenal gland to make cortisol and androgens.
ACTH stimulation test
One of the laboratory tests used to diagnosis adrenal insufficiency.
Acanthosis nigricans
A gray or black discoloration of the skin usually seen in the neck, the underarms, and the groin. It is a sign of insulin resistance.
Adrenal glands
Located above each kidney, these glands make the hormones: cortisol, aldosterone, and androgens. These hormones help to regulate water balance, blood sugar, blood pressure. They also play a role in male and female changes of puberty.
Addison’s disease
A rare disease where the adrenal glands do not make enough cortisol and/or aldosterone (adrenal hormones). There are different causes of Addison’s disease, but in many cases your body’s immune system may not recognize the adrenal gland and try destroy it.
Adrenal insufficiency
A condition where the adrenal glands do not make enough cortisol and/or aldosterone (adrenal hormones).
Aldosterone
A hormone made in the adrenal gland that helps a person’s body keep nutrients such as sodium and potassium in balance.
Ambiguous Genitalia
A birth defect that causes a baby’s genitals to look different from a typical boy or girl making it hard to tell the sex of the baby. (Additional lab and/or xray testing will be needed to confirm if baby is a boy or a girl.)
Amenorrhea
The lack of menstrual cycles in females. There are two types:
- Primary Amenorrhea: lack of first cycle or period after age 16 years.
- Secondary Amenorrhea: missed cycles or periods for longer than 6 months for girls of any age.
Androgens
Male sex hormones that cause and maintain the male sex changes. The main hormone is testosterone. These hormones are made in the testes and in the adrenal glands.
Antithyroid medications (Methimazole, Tapozole, and PTU)
This medication is used to treat any condition that causes too much thyroid hormone (Graves disease, thyroiditis). It lowers the amount of thyroid hormone produced by the thyroid gland.
Arm span
A measurement of the distance between the middle fingertips of the left and the right hands when arms are spread out as far as possible. This measurement may be used to help your doctor identify growth disorders.
Arginine Clonidine Growth Hormone Stimulation Tests
One of the laboratory tests used to diagnose growth hormone deficiency.
B
Bone age X-ray
An x-ray of the left hand and wrist. This x-ray may be a part of the growth evaluation. The doctor will compare the child’s chronological age (actual age) with their skeleton age (bone maturity). Delays or advancements in skeletal age from the child’s actual age may help support an endocrine diagnosis.
C
Congenital Adrenal Hyperplasia (CAH)
An inherited (born with this condition) disorder of the adrenal glands affecting the ability to make enough of the hormones cortisol and aldosterone, but too much of the androgen hormone. If CAH goes untreated, this condition can lead to death.
- Newborn girls with this disorder have a swelling of the clitoris (ambiguous genitalia).
- Newborn males may have no obvious changes but may enter into puberty as early as age 2-3 years.
- Salt wasting is a lack of aldosterone causing a child to lose large amounts of salt in his/her urine.
- Non salt wasting is a lack of cortisol with enough aldosterone.
Constitutional delay of growth (late bloomer)
A normal variation of growth. A child will grow at a normal rate but appears smaller than children the same age. The bone age and the start of puberty are usually delayed. The child with constitutional delay of growth tends to have a catch up growth spurt at puberty reaching a normal adult height.
Cortisol
A hormone made in the adrenal gland, sometimes called “stress hormone”. Cortisol plays a role in the body’s reaction to stress (ex. injury, illness) by controlling blood pressure and blood sugar.
Cushing disorder
This disorder is caused by problems with the pituitary gland that cause too much ACTH in the body. A person with this condition may have round swollen face, increased weight, weakened muscles, and bruise easily. An increase in blood pressure, blood sugar, and cholesterol may be seen.
D
Desmopressin (DDAVP)
An oral medication that helps to lessen the amount of urine a person will make. This medicine is often used in patients with Diabetes Insipidus.
DEXA Scan
A special x-ray that measures the amount of minerals, such as calcium, in your bones. The scan tells your doctor how strong your bones are.
Diabetes Insipidus
This condition is a result of missing antidiuretic hormone (ADH). This hormone is made by the pituitary gland and helps the kidneys balance the fluid in the body. A person with this condition may have a large amount of urine each day and be very thirsty. If untreated, this condition can lead to dehydration, problems with growth, weight gain and appetite.
E
Endocrinologist
A doctor that is a specialist in the function of the endocrine system and treatment of endocrine disorders.
Epiphyseal plate (epiphyses)
The growing ends of the long bones, sometimes called the growth plate.
Estrogen
A “female” hormone that is one of the hormones responsible for breast development, menstrual cycles (periods) and growth in girls. Estrogen is also produced in small amounts in males.
Estrogen Replacement Therapy
A medicine taken by mouth to replace the female hormone that helps to cause the puberty changes in girls. May be given in a oral or patch form.
F
Familial Short Stature
A normal growth pattern that matches closely to the child’s family members. The bone age usually matches the child’s age.
Fanconi Anemia
A rare inherited blood disorder that may lead to bone marrow failure. Children with Fanconi Anemia are at higher risk for having birth defects, kidney problems, growth problems, and cancer.
Fasting
A period of time when a person should stop eating or drinking for several hours. A doctor might ask a person to begin fasting at midnight the day before a test or procedure. Fasting usually includes avoiding everything taken in by mouth, even chewing gum and hard candy. Ask your doctor if you can take any medicines that are due during your fasting period.
Fellow
In the Endocrine program this is a three year training period for a pediatrician to become an endocrinologist.
Florinef
A medication taken by mouth that helps replaced the adrenal hormone, aldosterone.
G
Galactorrhea
Leaking of milk from the breast that can occur in both males and females who are not breastfeeding.
Goiter
Enlargement of the thyroid gland which is located in the front of the neck, behind the trachea (wind pipe).
Growth failure
A term that your doctor might use when your child has not grown at a normal speed (growth velocity) for his/her age.
Growth hormone
Helps with growth, bone and muscle strength, and sugar and fat metabolism.
Growth Hormone Deficiency (GHD)
This condition is due to the pituitary gland not making enough growth hormone for the body. A child with this deficiency will look younger and smaller than children of the same age.
Growth Hormone Replacement Therapy (Genotropin, Humatrope, Norditropin, Nutropin AQ, Saizen, Tev Tropin)
A daily shot that is given for growth hormone deficiency or growth failure.
Growth Velocity
The rate of growth a child experiences over a period of time. Normal growth velocities are based on age.
Gynecomastia
Enlargement of one or both breast in boys. It can be caused by estrogen and androgen hormone imbalance or sometimes from too much fatty tissue in overweight boys.
H
Hirsutism
Excessive growth of facial and body hair (usually in females).
Hyperinsulinism
Above normal levels of insulin in the blood of a person. It is the most common cause of low blood sugars seen in newborn babies. Hyperinsulism can also lead to decreased insulin sensitivity which may lead to high blood sugars. Treatment is aimed at keeping blood sugar levels normal and will be based on the cause of the condition.
Hyperparathyroidism
Overactive parathyroid gland causing too much calcium and low phosphorus levels in the blood. Calcium levels that are too high can cause weakness, dehydration, kidney stones, brittle bones, high blood pressure, seizures, or coma. Treatment is based on the cause of the condition.
Hyperprolactemia
An increase of the hormone prolactin secreted from the pituitary gland. An increased prolactin level can cause breast drainage (galactorrhea), irregular menstrual cycles, or enlarged breasts.
Hyperthyroidism
An increase in the production of thyroid hormone from the thyroid gland, which causes, trouble sleeping, diarrhea, tiredness, goiter, feeling hot, fast heart rate, weight loss, bulging of eyes, or shakiness. Treatment may include antithyroid medications and management of fast heart rates. In some cases radioactive iodine and/or surgery could be necessary.
Hypopituitary
A condition resulting from decreased secretion of pituitary hormones.
Hydrocortisone
A medication that replaces the hormone cortisol. It is taken by patients who have conditions of adrenal insufficiency.
Hypothyroid, Congenital
A condition found in 1 out of every 4000 newborns. All babies are tested for congenital hypothyroidism within the first week of life. When a baby has this condition, his/her thyroid gland is not producing enough hormone for the brain and body to grow and develop.
Hypothyroid, Acquired
A disorder that does not allow the thyroid gland to make enough thyroid hormone for the brain and body to grow and develop normally. Although, the condition is more common in teen girls, it can be found in boys and girls of any age.
I
Idiopathic Short Stature
Children presenting with <3rd percentile for height on standard growth chart. After evaluation by an endocrinologist, no medical conditions which cause growth failure are found. Patients may be candidates for growth hormone therapy.
IGF-1
A hormone that plays an important role in growth. IGF-1 is influenced by growth hormone and nutritional status. The amount of hormone found in the blood is useful in screening for growth hormone deficiency. .
IGF-1 deficiency
A condition in which the body does not make enough IGF-1. Usually this condition causes short stature.
Insulin
A hormone made in the pancreas that has many functions. One important function is helping your body control your blood sugar.
Insulin Resistance
A condition the body needs more insulin than normal to control the blood sugar that increases a person’s risk of diabetes and heart disease. Usually associated with obesity.
J
K
Kallmann’s Syndrome
A syndrome in which the body makes low levels of the puberty hormones. People with this syndrome have poor or absent ability to smell. An evaluation by pediatric endocrinologist is recommended at time of puberty to assist with medications to promote puberty.
Karyotype
A test that looks at the genetic make-up of a person. The test looks at the number, shape and size of the chromosomes (cell structures that carry DNA or genes). Extra, missing or abnormal chromosomes can explain problems with growth, and development.
Klinefelters Syndrome
This condition occurs in 1 out of 500-1000 male births. Boys are born with an extra X chromosome. Boys may present with tall, slim stature and delayed puberty. May also experience behavior problems and delayed language skills. Testosterone therapy recommended for boys age 11-12 after evaluation by pediatric endocrinologist. See support group at Klinefeltersyndrome.org.
L
Leuprolide Stim Test
Specialized blood test used for diagnosing early or delayed puberty. See leuprolide stim test.
Levothyroxine
Generic name for thyroid replacement hormone. Brand names may include Synthroid, Levoxyl.
Luteinizing Hormone (LH)
A puberty hormone that stimulates the body to produce testosterone or estrogen.
Lupron Depot
A medication used to suppress puberty. Given by an injection or shot.
M
Marfan syndrome
Marfan syndrome is a genetic disorder with an incidence rate of 1 in 5,000 individuals that affects the body's connective tissues, or the tissues in between the main cells of each organ of the body. A person with Marfan syndrome will usually be tall, slender and somewhat loose jointed or limber. The arms, legs, fingers and toes may be disproportionately long when compared to the trunk. See health topic Marfan Syndrome.
McCune Albright Syndrome: A genetic condition affecting bone health, puberty and thyroid. Characteristics may include early puberty, bone fracture, and café au lait spots (irregular brown spots on the skin). Evaluation by endocrinology to determine medications required to optimize bone health and monitoring of pubertal advancement.
Metformin
An oral medication that has been shown to improve the body's use of insulin. This medication is often used in patients with Type 2 Diabetes Mellitus, polycystic ovary syndrome and obesity. Brand name glucophage.
Methimazole
A generic name for Tapazole. Used as an anti-thyroid agent in the treatment of hyperthyroidism.
N
Noonan Syndrome
Occurs in about 1 in 1,000 to 1 in 2,500 live births. The actual genetic abnormality has not yet been discovered. The adolescent growth spurt is often blunted or delayed and 60 percent of males have undescended testes. In addition to delay in growth, sexual development is variable and may also be delayed. See Noonan Syndrome.
O
Obesity
Too much fat in the body caused by eating more calories than you use. Obesity increases your risk of diabetes, and heart disease.
P
Pelvic Ultrasound
See health topic.
Pituitary gland
Located at the bottom of the brain, this pea-sized gland helps to control many endocrine functions. The pituitary gland plays an important role in growth, fluid balance, thyroid function and puberty, just to name a few.
Precocious Puberty
See health topic.
Premature Adrenarche
The early growth of pubic hair before the age of 8 years in girls and the age of 9 years in boys.
Premature Thelarche
The early appearance of breast development in females who show no other signs of puberty.
Prolactin
A hormone released by the pituitary gland that controls the milk production in the breast tissue.
PTU (Propylthiouracil)
A medication used to treat hyperthyroidism. This medicine slows or stops the thyroid gland from making too much thyroid hormone.
Puberty
A time during which a child’s reproductive system matures, body changes and growth increases.
Q
R
Radioactive iodine (RAI)
Radioactive iodine is a medication that is given safely by mouth to stop the thyroid gland from making too much thyroid hormone in a patient with an overactive gland.
Rickets
A disorder that causes softening and weakening of the bone in children who have low levels of vitamin D.
S
Septo-optic dysplasia
A rare condition in which there is abnormal development in part of brain that can cause changes in a child’s eyes and also problems in the pituitary gland.
Small for gestational age (SGA)
SGA is a term used in newborns that are smaller than the 3rd percentile for height and weight for age. The newborn baby’s age is determined by counting the number of weeks since the mothers last menstrual period.
Short stature
See Health Topic.
Solu-cortef
A medicine given to children with adrenal hyperplasia in times of illness. This medicine is given by a shot when a child is vomiting. Solu-cortef prevents a child from a life-threatening condition called shock.
Steroids
Medication, such as cortef or prednisone that is taken to replace cortisol hormones.
Subcutaneous injection
Some medications are to be given into subcutaneous tissue, which is the fatty layer of tissue just under the skin. They are sometimes called 'Sub-Q' injections.
Supprelin
A medication used to stop precocious puberty that comes in a device that can be placed underneath the skin.
T
Tanner Stage
Medical term used for stages of puberty ranging on scale of 1-5.
Tapazole
A medication used to treat hyperthyroidism. This medicine slows or stops the thyroid gland from making too much thyroid hormone; also called methimazole.
Testosterone
A “male” hormone that is made by the testes in males and by the ovaries in females. Normal levels of testosterone are important for energy and bone strength.
Testosterone Replacement Therapy
This is a male hormone replacement medicine given either by applying to the skin every day or by a shot every 2 to 4 weeks in the muscle. This will help start puberty or maintain the male sex changes of adults.
Thyroid gland
A small butterfly shaped gland of the endocrine system located in the neck area that makes thyroid hormone.
Thyroid scan
Nuclear scan used to evaluate the function of thyroid and or thyroid nodules.
Thyroid nodule
A lump or swelling felt in the neck in the area of the thyroid gland.
Thyroidectomy
Surgical removal of the thyroid gland.
Thyroid Stimulating Hormone (TSH)
Hormone made in the brain that tells the thyroid gland to make thyroid hormone. The amount of TSH in your brain is making can be checked with a blood test.
Turner Syndrome
A genetic condition affecting girls with an incidence of 1 in 2500 female births. These girls need screening for possible problems related to heart, kidneys, growth, pubertal development and developmental delays. See Turner Clinic at Cincinnati Children’s and the support group at Turnersyndrome.org.
Type1 Diabetes Mellitus
See Health Topic.
Type 2 Diabetes Mellitus
See Health Topic.
U
V
Vitamin D
Vitamin that helps the body absorb nutrients such as calcium and phosphorus that makes the bones stronger.
W
Water deprivation test
Test used to check the ability of kidneys to concentrate urine
X
Y
Z
