Description: 17-hydroxyprogesterone is a test that is measuring the levels of 17-OHP in the blood. 17-OHP is used to detect and monitor the treatment processes for congenital adrenal hyperplasia.
Also Known As: 17-OHP Test, 17-OH Progesterone Test
Collection Method: Blood Draw
Specimen Type: Serum
Test Preparation: No preparation required
When is this test ordered?
The 17-OHP test is regularly ordered as part of a newborn screening and may be repeated if the screening test results are elevated to confirm the initial findings.
When an infant or young kid exhibits signs and symptoms of adrenal insufficiency or CAH, a 17-OHP test may be administered.
When the milder type of CAH is suspected, this test may be ordered in older children or adults. When a girl or woman is having symptoms that could be caused by CAH or another illness, such as PCOS, the 17-OHP test can be used.
Boys and men may be tested if they are experiencing early puberty or infertility.
When a person is diagnosed with 21-hydroxylase deficiency, a 17-OHP test may be ordered on a regular basis to assess treatment effectiveness.
What is being tested?
17-hydroxyprogesterone is a steroid hormone that is created during the cortisol production process. This test detects and/or evaluates congenital adrenal hyperplasia, a hereditary disorder characterized by decreased adrenal cortisol and aldosterone production and increased male sex hormone production.
Cholesterol is the source of 17-OHP. It is a precursor of active steroid hormones, rather than an active steroid hormone.
Cortisol is a hormone produced by the adrenal glands that aids in the breakdown of protein, carbohydrates, and fats, regulates the immune system, and maintains blood pressure. Other steroid hormones produced by the adrenal glands include aldosterone, which helps regulate salt levels and blood pressure, and androgens, which, like testosterone, cause male sexual characteristics and other consequences.
The processes in the synthesis of cortisol necessitate the use of several enzymes. Inadequate levels of cortisol are produced when one or more of these enzymes are insufficient or malfunctioning, as is the case with CAH. CAH is caused by a partial or total loss of the enzyme 21-hydroxylase, which accounts for around 90% of cases.
The adrenal gland grows in size because a low level of cortisol induces an increase in the level of a specific pituitary hormone that drives adrenal growth and hormone production. The increased size and activity, however, are insufficient to overcome the cortisol production bottleneck. Other chemicals that do not require the faulty enzyme, such as 17-hydroxyprogesterone and androgens, are created in excess. This is why 17-OHP testing can aid in the detection of CAH.
CAH is a set of hereditary illnesses characterized by cortisol-related enzyme deficits and caused by particular gene mutations. A mutation in the 21-hydroxylase gene causes around 90% of CAH cases, which can be diagnosed by an increase in 17-OHP in the blood. When both genes, one from each parent, contain mutations that reduce or cease the activity of the enzyme for which the gene codes, the disease is caused. Parents could be carriers, and carriers could not show any symptoms.
CAH with 21-hydroxylase deficiency can be inherited in two forms: severe and mild.
Severe forms can result in kids being born with severe aldosterone and cortisol deficits, necessitating medical treatment. This severe variant is most commonly found in infancy or early childhood through regular newborn screening. It may manifest in early childhood with signs and symptoms such as vomiting, listlessness, lack of energy, not eating properly, failure to thrive, dehydration, and low blood pressure if it is not found through screening, especially with severe sickness.
Excess male sex hormones can cause the development of male characteristics in females. Female babies' sex organs may not be obviously male or female, making it difficult to tell their gender at first. During childhood and adolescence, females may have excessive hair development on the face and body, as well as other male secondary sexual traits such as irregular menstruation. Men with this disorder may not appear different at birth, but they might develop sexual traits early in life, putting them at risk for fertility problems later in life.
Only partial lack of the enzyme may be present in the milder, though more prevalent type of CAH caused by 21-hydroxylase deficiency. This kind of CAH, also known as late-onset or non-classical CAH, can manifest symptoms at any age during childhood, adolescence, or adulthood. Symptoms might be nonspecific, develop slowly over time, and differ from one person to the next. Though this type of CAH is rarely life-threatening, it can cause growth, development, and puberty issues in children, as well as infertility in adults.
Related Tests and Panels:
- Congenital Adrenal Hyperplasia
- Polycystic Ovary Syndrome
- Adrenal Insufficiency
- Addison Disease
- Endocrine Syndromes
How is this test used by my health care provider?
The 17-hydroxyprogesterone test is used to detect congenital adrenal hyperplasia and can be used in the conjunction with other tests to diagnose and track CAH.
In the United States, the 17-OHP test is frequently ordered as part of newborn screening to detect CAH caused by a lack of 21-hydroxylase.
The 17-OHP test can be used to screen for CAH in older children and adults before symptoms develop, or to confirm a CAH diagnosis in persons who are already experiencing symptoms.
The presence of 17-OHP in the blood can help doctors diagnose CAH in older children and people who have a milder, "late-onset" variant of the disease.
A 17-OHP test, along with plasma renin activity, androstenedione, and testosterone assays, may be used to evaluate the success of treatment if someone is diagnosed with 21-hydroxylase insufficiency.
In women with symptoms such as abundant face and body hair and irregular periods, a 17-OHP test, along with other hormone testing, may be done to help rule out CAH. Women with probable polycystic ovarian syndrome and infertility, as well as those with suspected adrenal or ovarian malignancies, fall under this category.
False-positive results have been reported with 17-OHP testing, particularly the newborn screening test. Other tests may be performed if the level is higher but not to the point where it is indicative of CAH.
As a follow-up test, an ACTH test may be ordered. ACTH stimulation causes a significant increase in 17-OHP levels in CAH.
CYP21A2 gene mutations that cause the disorder may be detected by genetic testing.
A karyotype test may be ordered as a follow-up test to discover chromosome problems and to assist in determining the gender of a newborn.
Electrolytes may be ordered to determine the sodium and potassium levels of a person.
What do my 17 Hydroxyprogesterone test results mean?
If a newborn or infant has highly elevated 17-OHP levels, he or she is most likely suffering from CAH. If a person's levels are somewhat elevated, he or she may have a milder case of CAH or an 11-beta-hydroxylase deficiency.
The absence of CAH due to a 21-hydroxylase deficit is most often shown by normal 17-OHP findings.
In a person with CAH, low or declining amounts suggest a positive response to treatment. High or rising levels may suggest that treatment has to be changed.
We advise having your results reviewed by a licensed medical physician for proper interpretation of your results.