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Currently, in the United States and over 40 other countries, every child born is screened for 21-hydroxylaase CAH at birth. This test will detect elevated levels of 17-hydroxy-progesterone (17-OHP). Detecting high levels of 17-OHP enables early detection of CAH. Newborns detected early enough can be placed on medication and live a relatively normal life.
The screening process, however, is characterized by a high false positive rate. In one study, CAH screening had the lowest positive predictive value (111 true-positive cases among 20,647 abnormal screening results in a 2-year period, or 0.53%, compared with 6.36% for biotinidase deficiency, 1.84% for congenital hypo-thyroidism, 0.56% for classic galactosemia, and 2.9% for phenylketonuria). According to this estimate, 200 unaffected newborns required clinical and laboratory follow-up for every true case of CAH.
Conditions justifying newborn screening for any disorder include (1) a simple test with an acceptable sensitivity and specificity, (2) a dire consequence if not diagnosed early, (3) an effective treatment if diagnosed, and (4) a frequency in the population high enough to justify the expense. In the last decade more states and countries are adopting newborn screening for salt-wasting CAH due to 21-hydroxylase deficiency, which leads to death in the first month of life if not recognized.
The salt-wasting form of CAH has an incidence of 1 in 15,000 births and is potentially fatal within a month if untreated. Steroid replacement is a simple, effective treatment. However, the screening test itself is less than perfect. While the 17α-hydroxyprogesterone level is easy to measure and sensitive (rarely missing real cases), the test has a poorer specificity. Screening programs in the United States have reported that 99% of positive screens turn out to be false positives upon investigation of the infant. This is a higher rate of false positives than the screening tests for many other congenital metabolic diseases.
When a positive result is detected, the infant must be referred to a pediatric endocrinologist to confirm or disprove the diagnosis. Since most infants with salt-wasting CAH become critically ill by 2 weeks of age, the evaluation must be done rapidly despite the high false positive rate.
Levels of 17α-hydroxyprogesterone, androstenedione, and cortisol may play a role in screening.
Genetic analysis can be helpful to confirm a diagnosis of CAH but it is not necessary if classic clinical and laboratory findings are present.
In classic 21-hydroxylase deficiency, laboratory studies will show:
Classic 21-hydroxylase deficiency typically causes 17α-hydroxyprogesterone blood levels >242 nmol/L. (For comparison, a full-term infant at three days of age should have <3 nmol/L. Many neonatal screening programs have specific reference ranges by weight and gestational age because high levels may be seen in premature infants without CAH.) Salt-wasting patients tend to have higher 17α-hydroxyprogesterone levels than non-salt-wasting patients. In mild cases, 17α-hydroxyprogesterone may not be elevated in a particular random blood sample, but it will rise during a corticotropin stimulation test.
If one of these tests shows a deficiency of hormones produced by the pituitary, magnetic resonance imaging (MRI) scan of the pituitary is the first step in identifying an underlying cause. MRI may show various tumors and may assist in delineating other causes. Tumors smaller than 1 cm are referred to as "microadenomas", and larger lesions are called "macroadenomas". Computed tomography with radiocontrast may be used if MRI is not available. Formal visual field testing by perimetry is recommended, as this would show evidence of optic nerve compression by a tumor.
Other tests that may assist in the diagnosis of hypopituitarism, especially if no tumor is found on the MRI scan, are ferritin (elevated in hemochromatosis), angiotensin converting enzyme (ACE) levels (often elevated in sarcoidosis), and human chorionic gonadotropin (often elevated in tumor of germ cell origin). If a genetic cause is suspected, genetic testing may be performed.
Since CAH is an autosomal recessive disease, most children with CAH are born to parents unaware of the risk and with no family history. Each child will have a 25% chance of being born with the disease. Families typically wish to minimize the degree of virilization of a girl. There is no known prenatal harm to a male fetus from CAH, so treatment can begin at birth.
Adrenal glands of female fetuses with CAH begin producing excess testosterone by the 9th week of gestation. The most important aspects of virilization (urogenital closure and phallic urethra) occur between 8 and 12 weeks. Theoretically, if enough glucocorticoid could be supplied to the fetus to reduce adrenal testosterone production by the 9th week, virilization could be prevented and the difficult decision about timing of surgery avoided.
The challenge of preventing severe virilization of girls is twofold: detection of CAH at the beginning of the pregnancy, and delivery of an effective amount of glucocorticoid to the fetus without causing harm to the mother.
The first problem has not yet been entirely solved, but it has been shown that if dexamethasone is taken by a pregnant woman, enough can cross the placenta to suppress fetal adrenal function.
At present no program screens for risk in families who have not yet had a child with CAH. For families desiring to avoid virilization of a second child, the current strategy is to start dexamethasone as soon as a pregnancy has been confirmed even though at that point the chance that the pregnancy is a girl with CAH is only 12.5%. Dexamethasone is taken by the mother each day until it can be safely determined whether she is carrying an affected girl.
Whether the fetus is an affected girl can be determined by chorionic villus sampling at 9–11 weeks of gestation, or by amniocentesis at 15–18 weeks gestation. In each case the fetal sex can be determined quickly, and if the fetus is a male the dexamethasone can be discontinued. If female, fetal DNA is analyzed to see if she carries one of the known abnormal alleles of the "CYP21" gene. If so, dexamethasone is continued for the remainder of the pregnancy at a dose of about 1 mg daily.
Most mothers who have followed this treatment plan have experienced at least mild cushingoid effects from the glucocorticoid but have borne daughters whose genitalia are much less virilized.
Growth hormone deficiency is almost certain if all other pituitary tests are also abnormal, and insulin-like growth factor 1 (IGF-1) levels are decreased. If this is not the case, IGF-1 levels are poorly predictive of the presence of GH deficiency; stimulation testing with the insulin tolerance test is then required. This is performed by administering insulin to lower the blood sugar to a level below 2.2 mmol/l. Once this occurs, growth hormone levels are measured. If they are low despite the stimulatory effect of the low blood sugars, growth hormone deficiency is confirmed. The test is not without risks, especially in those prone to seizures or are known to have heart disease, and causes the unpleasant symptoms of hypoglycemia. Alternative tests (such as the growth hormone releasing hormone stimulation test) are less useful, although a stimulation test with arginine may be used for diagnosis, especially in situations where an insulin tolerance test is thought to be too dangerous. If GH deficiency is suspected, and all other pituitary hormones are normal, two different stimulation tests are needed for confirmation.
If morning cortisol levels are over 500 nmol/l, ACTH deficiency is unlikely, whereas a level less than 100 is indicative. Levels between 100-500 require a stimulation test. This, too, is done with the insulin tolerance test. A cortisol level above 500 after achieving a low blood sugar rules out ACTH deficiency, while lower levels confirm the diagnosis. A similar stimulation test using corticotropin-releasing hormone (CRH) is not sensitive enough for the purposes of the investigation. If the insulin tolerance test yields an abnormal result, a further test measuring the response of the adrenal glands to synthetic ACTH (the ACTH stimulation test) can be performed to confirm the diagnosis. Stimulation testing with metyrapone is an alternative. Some suggest that an ACTH stimulation test is sufficient as first-line investigation, and that an insulin tolerance test is only needed if the ACTH test is equivocal. The insulin tolerance test is discouraged in children. None of the tests for ACTH deficiency are perfect, and further tests after a period of time may be needed if initial results are not conclusive.
Symptoms of diabetes insipidus should prompt a formal fluid deprivation test to assess the body's response to dehydration, which normally causes concentration of the urine and increasing osmolarity of the blood. If these parameters are unchanged, desmopressin (an ADH analogue) is administered. If the urine then becomes concentrated and the blood osmolarity falls, there is a lack of ADH due to lack of pituitary function ("cranial diabetes insipidus"). In contrast, there is no change if the kidneys are unresponsive to ADH due to a different problem ("nephrogenic diabetes insipidus").
Like the other forms of CAH, suspicion of severe 3β-HSD CAH is usually raised by the appearance of the genitalia at birth or by development of a salt-wasting crisis in the first month of life. The diagnosis is usually confirmed by the distinctive pattern of adrenal steroids: elevated pregnenolone, 17α-hydroxypregnenolone, DHEA, and renin. In clinical circumstances this form of CAH has sometimes been difficult to distinguish from the more common 21-hydroxylase deficient CAH because of the 17OHP elevation, or from simple premature adrenarche because of the DHEA elevation.
For the diagnosis of hyperpituitarism it depends on the cell type(s) affected, clinical manifestations of hormone excess may include, gigantism or acromegaly, which can be identified by clinical and radiographic results. Cushing's disease diagnosis is done with a physical examination, laboratory tests and X rays of the pituitary glands (to locate tumors) For prolactinoma, diagnosis comes in the form of the measurement of serum prolactin levels and x-ray of pituitary gland.
Pituitary incidentalomas are pituitary tumors that are characterized as an incidental finding. They are often discovered by computed tomography (CT) or magnetic resonance imaging (MRI), performed in the evaluation of unrelated medical conditions such as suspected head trauma, in cancer staging or in the evaluation of nonspecific symptoms such as dizziness and headache. It is not uncommon for them to be discovered at autopsy. In a meta-analysis, adenomas were found in an average of 16.7% in postmortem studies, with most being microadenomas (<10mm); macrodenomas accounted for only 0.16% to 0.2% of the decedents. While non-secreting, noninvasive pituitary microadenomas are generally considered to be literally as well as clinically benign, there are to date scant studies of low quality to support this assertion.
It has been recommended in the current Clinical Practice Guidelines (2011) by the Endocrine Society - a professional, international medical organization in the field of endocrinology and metabolism - that all patients with pituitary incidentalomas undergo a complete medical history and physical examination, laboratory evaluations to screen for hormone hypersecretion and for hypopituitarism. If the lesion is in close proximity to the optic nerves or optic chiasm, a visual field examination should be performed. For those with incidentalomas which do not require surgical removal, follow up clinical assessments and neuroimaging should be performed as well follow-up visual field examinations for incidentalomas that abut or compress the optic nerve and chiasm and follow-up endocrine testing for macroincidentalomas.
An adrenal "incidentaloma" is an adrenal tumor found by coincidence without clinical symptoms or suspicion. It is one of the more common unexpected findings revealed by computed tomography (CT), magnetic resonance imaging (MRI), or ultrasonography.
In these cases, a dexamethasone suppression test is often used to detect cortisol excess, and metanephrines or catecholamines for excess of these hormones. Tumors under 3 cm are generally considered benign and are only treated if there are grounds for a diagnosis of Cushing's syndrome or pheochromocytoma. Radiodensity gives a clue in estimating malignancy risk, wherein a tumor with 10 Hounsfield units or less on an unenhanced CT is probably a lipid-rich adenoma.
Hormonal evaluation includes:
- 1-mg overnight dexamethasone suppression test
- 24-hour urinary specimen for measurement of fractionated metanephrines and catecholamines
- Blood plasma aldosterone concentration and plasma renin activity, "if hypertension is present"
On CT scan, benign adenomas typically are of low radiographic density (due to fat content) and show rapid washout of contrast medium (50% or more of the contrast medium washes out at 10 minutes). If the hormonal evaluation is negative and imaging suggests benign, followup should be considered with imaging at 6, 12, and 24 months and repeat hormonal evaluation yearly for 4 years
Early histological features expected to be seen on examination of gynecomastic tissue attained by fine-needle aspiration biopsy include the following: proliferation and lengthening of the ducts, an increase in connective tissue, an increase in inflammation and swelling surrounding the ducts, and an increase in fibroblasts in the connective tissue. Chronic gynecomastia may show different histological features such as increased connective tissue fibrosis, an increase in the number of ducts, less inflammation than in the acute stage of gynecomastia, increased subareolar fat, and hyalinization of the stroma. When surgery is performed, the gland is routinely sent to the lab to confirm the presence of gynecomastia and to check for tumors under a microscope. The utility of pathologic examination of breast tissue removed from male adolescent gynecomastia patients has recently been questioned due to the rarity of breast cancer in this population.
The spectrum of gynecomastia severity has been categorized into a grading system:
- Grade I: Minor enlargement, no skin excess
- Grade II: Moderate enlargement, no skin excess
- Grade III: Moderate enlargement, skin excess
- Grade IV: Marked enlargement, skin excess
Hormonal assay : there may be low level of T4, TSH, Estrogen, Gonadotropin, Cortisol and ACTH depending on the extent of necrosis
MRI of the pituitary and hypothalamus: this helps to exclude tumor or other pathologies.
A doctor will test for prolactin blood levels in women with unexplained milk secretion (galactorrhea) or irregular menses or infertility, and in men with impaired sexual function and milk secretion. If prolactin is high, a doctor will test thyroid function and ask first about other conditions and medications known to raise prolactin secretion. While a plain X-ray of the bones surrounding the pituitary may reveal the presence of a large macro-adenoma, the small micro-adenoma will not be apparent. Magnetic resonance imaging (MRI) is the most sensitive test for detecting pituitary tumours and determining their size. MRI scans may be repeated periodically to assess tumour progression and the effects of therapy. Computed Tomography (CT scan) also gives an image of the pituitary, but it is less sensitive than the MRI.
In addition to assessing the size of the pituitary tumour, doctors also look for damage to surrounding tissues, and perform tests to assess whether production of other pituitary hormones is normal. Depending on the size of the tumour, the doctor may request an eye exam with measurement of visual fields.
The hormone prolactin is downregulated by dopamine and is upregulated by oestrogen. A falsely-high measurement may occur due to the presence of the biologically-inactive macroprolactin in the serum. This can show up as high prolactin in some types of tests, but is asymptomatic.
Diagnosis is made first by diagnosing Cushing's syndrome, which can be difficult to do clinically since the most characteristic symptoms only occur in a minority of patients. Some of the biochemical diagnostic tests used include salivary and blood serum cortisol testing, 24-hour urinary free cortisol (UFC) testing, the dexamethasone suppression test (DST), and bilateral inferior petrosal sinus sampling (BIPSS). No single test is perfect and multiple tests should always be used to achieve a proper diagnosis. Diagnosing Cushing's disease is a multidisciplinary process involving doctors, endocrinologists, radiologists, surgeons, and chemical pathologists.
Once Cushing's syndrome has been diagnosed, the first step towards finding the cause is measuring plasma corticotropin concentrations. A concentration consistently below 1.1 pmol/L is classified as corticotropin-independent and does not lead to a diagnosis of Cushing's disease. In such cases, the next step is adrenal imaging with CT. If plasma corticotropin concentrations are consistently above 3.3 pmol/L, then corticotropin-dependent Cushing's syndrome is most likely. Any intermediate values need to be cautiously interpreted and a corticotropin-releasing hormone (CRH) test is advised in order to confirm corticotropin dependency. If corticotropin-dependent Cushing's syndrome is determined then the next step is to distinguish between Cushing's disease and ectopic corticotropin syndrome. This is done via a combination of techniques including CRH, high-dose DST, BIPSS, and pituitary MRI.
Two dexamethasone suppression tests (DSTs) are generally used, the overnight and 48-h DSTs. For both tests, a plasma cortisol level above 50 nmol/L is indicative of Cushing's disease. However, 3-8% of patients with Cushing's disease will test negative due to a retention of dexamethasone suppression abilities. For non-Cushing or healthy patients, the false-positive rate is 30%. The 48-h DST is advantageous since it is more specific and can be done by outpatients upon proper instruction. In the high-dose 48-h DST, 2 mg of dexamethasone is given every 6 hours for 48 hours or a single dose of 8 mg is given. This test is not needed if the 48-h low-dose DST has shown suppression of cortisol by over 30%. These tests are based on the glucocorticoid sensitivity of pituitary adenomas compared to non-pituitary tumors.
Administration of corticotropin releasing hormone (CRH) can differentiate this condition from ectopic ACTH secretion. In a patient with Cushing's disease, the tumor cells will be stimulated to release corticotropin and elevated plasma corticotropin levels will be detected. This rarely occurs with ectopic corticotropin syndrome and thus is quite useful for distinguishing between the two conditions. If ectopic, the plasma ACTH and cortisol levels should remain unchanged; if this is pituitary related, levels of both would rise. The CRH test uses recombinant human or bovine-sequence CRH, which is administered via a 100μg intravenous bolus dose. The sensitivity of the CRH test for detecting Cushing's disease is 93% when plasma levels are measured after fifteen and thirty minutes. However, this test is used only as a last resort due to its high cost and complexity.
A CT or MRI of the pituitary may also show the ACTH secreting tumor if present. However, in 40% of Cushing's disease patients MRI is unable to detect a tumor. In one study of 261 patients with confirmed pituitary Cushing's disease, only 48% of pituitary lesions were identified using MRI prior to surgery. The average size of tumor, both those that were identified on MRI and those that were only discovered during surgery, was 6 mm.
A more accurate but invasive test used to differentiate pituitary from ectopic or adrenal Cushing's syndrome is inferior petrosal sinus sampling. A corticotropin gradient sample via BIPSS is required to confirm diagnosis when pituitary MRI imaging and biochemical diagnostic tests have been inconclusive. A basal central:peripheral ratio of over 3:1 when CRH is administered is indicative of Cushing’s disease. This test has been the gold standard for distinguishing between Cushing's disease and ectopic corticotropin syndrome. The BIPSS has a sensitivity and specificity of 94% for Cushing's disease but it is usually used as a last resort due to its invasiveness, rare but serious complications, and the expertise required to perform it.
Another diagnostic test used is the urinary free cortisol (UFC) test, which measures the excess cortisol excreted by the kidneys into the urine. Results of 4x higher cortisol levels than normal are likely to be Cushing's disease. This test should be repeated three times in order to exclude any normally occurring periods of hypercortisolism. The UFC test has a specificity of 81% and thus has a high rate of false-positives that are due to pseudo-Cushing states, sleep apnea, polycystic ovary syndrome, familial glucocorticoid resistance, and hyperthyroidism.
The late-night or midnight salivary cortisol test has been gaining support due to its ease of collection and stability at room temperature, therefore it can be assigned to outpatients. The test measures free circulating cortisol and has both a sensitivity and specificity of 95-98%. This test is especially useful for diagnosing children.
Treatment (for hyperpituitarism) in the case of prolactinoma consists of long-term medical management. Dopamine agonists are strong suppressors of PRL secretion and establish normal gonadal function. It also inhibits tumor cell replication (in some cases causes tumor shrinkage) Treatment for gigantism begins with establishing target goals for IGF-1, transsphenoidal surgery (somatostatin receptor ligands- preoperatively) and postoperative imaging assessment. For Cushing's disease there is surgery to extract the tumor; after surgery, the gland may slowly start to work again, though not always.
Evaluation of growth hormone hyper-secretion cannot be excluded with a single normal GH level due to diurnal variation. However, a random blood sample showing markedly elevated GH is adequate for diagnosis of GH hyper-secretion. Additionally, a high-normal GH level that fails to suppress with administration of glucose is also sufficient for a diagnosis of GH hyper-secretion.
Insulin-like Growth Factor-1 (IGF-1) is an excellent test for evaluation of GH hyper-secretion. It does not undergo diurnal variation and will thus be consistently elevated in GH hyper-secretion and therefore patients with gigantism. A single normal IGF-1 value will reliably exclude GH hyper-secretion.
Hypertension and mineralocorticoid excess is treated with glucocorticoid replacement, as in other forms of CAH.
Most genetic females with both forms of the deficiency will need replacement estrogen to induce puberty. Most will also need periodic progestin to regularize menses. Fertility is usually reduced because egg maturation and ovulation is poorly supported by the reduced intra-ovarian steroid production.
The most difficult management decisions are posed by the more ambiguous genetic (XY) males. Most who are severely undervirilized, looking more female than male, are raised as females with surgical removal of the nonfunctional testes. If raised as males, a brief course of testosterone can be given in infancy to induce growth of the penis. Surgery may be able to repair the hypospadias. The testes should be salvaged by orchiopexy if possible. Testosterone must be replaced in order for puberty to occur and continued throughout adult life.
The best diagnostic tool to confirm adrenal insufficiency is the ACTH stimulation test; however, if a patient is suspected to be suffering from an acute adrenal crisis, immediate treatment with IV corticosteroids is imperative and should not be delayed for any testing, as the patient's health can deteriorate rapidly and result in death without replacing the corticosteroids.
Dexamethasone should be used as the corticosteroid if the plan is to do the ACTH stimulation test at a later time as it is the only corticosteroid that will not affect the test results.
If not performed during crisis, then labs to be run should include: random cortisol, serum ACTH, aldosterone, renin, potassium and sodium. A CT of the adrenal glands can be used to check for structural abnormalities of the adrenal glands. An MRI of the pituitary can be used to check for structural abnormalities of the pituitary. However, in order to check the functionality of the Hypothalamic Pituitary Adrenal (HPA) Axis the entire axis must be tested by way of ACTH stimulation test, CRH stimulation test and perhaps an Insulin Tolerance Test (ITT). In order to check for Addison’s Disease, the auto-immune type of primary adrenal insufficiency, labs should be drawn to check 21-hydroxylase autoantibodies.
If acromegaly is suspected, medical imaging and medical laboratory investigations are generally used together to confirm or rule out the presence of this condition.
IGF1 provides the most sensitive lab test for the diagnosis of acromegaly, and a GH suppression test following an oral glucose load, which is a very specific lab test, will confirm the diagnosis following a positive screening test for IGF1. A single value of the GH is not useful in view of its pulsatality (levels in the blood vary greatly even in healthy individuals). GH levels taken 2 hours after a 75- or 100-gram glucose tolerance test are helpful in the diagnosis: GH levels are suppressed below 1 μg/l in normal people, and levels higher than this cutoff are confirmatory of acromegaly.
Other pituitary hormones must be assessed to address the secretory effects of the tumor, as well as the mass effect of the tumor on the normal pituitary gland. They include thyroid stimulating hormone (TSH), gonadotropic hormones (FSH, LH), adrenocorticotropic hormone, and prolactin.
An MRI of the brain focusing on the sella turcica after gadolinium administration allows for clear delineation of the pituitary and the hypothalamus and the location of the tumor. A number of other overgrowth syndromes can result in similar problems.
Management of salt-wasting crises and mineralocorticoid treatment are as for other forms of salt-wasting congenital adrenal hyperplasias: saline and fludrocortisone.
Glucocorticoids can be provided at minimal replacement doses because there is no need for suppression of excessive adrenal androgens or mineralocorticoids. As with other forms of adrenal insufficiency, extra glucocorticoid is needed for stress coverage.
As with other forms of CAH, the primary therapy of 11β-hydroxylase deficient CAH is lifelong glucocorticoid replacement in sufficient doses to prevent adrenal insufficiency and suppress excess mineralocorticoid and androgen production.
Salt-wasting in infancy responds to intravenous saline, dextrose, and high dose hydrocortisone, but prolonged fludrocortisone replacement is usually not necessary. The hypertension is ameliorated by glucocorticoid suppression of DOC.
Long term glucocorticoid replacement issues are similar to those of 21-hydroxylase CAH, and involve careful balance between doses sufficient to suppress androgens while avoiding suppression of growth. Because the enzyme defect does not affect sex steroid synthesis, gonadal function at puberty and long-term fertility should be normal if adrenal androgen production is controlled. See congenital adrenal hyperplasia for a more detailed discussion of androgen suppression and fertility potential in adolescent and adult women.
Female patients may show symptoms of hyperandrogenism in their early life, but physicians become more concerned when the patient is in her late teens or older.
Hyperandrogenism is most often diagnosed by checking for signs of hirsutism according to a standardized method that scores the range of excess hair growth.
Checking medical history and a physical examination of symptoms are used for an initial diagnosis. Patient history assessed includes age at thelarche, adrenarche, and menarche; patterns of menstruation; obesity; reproductive history; and the start and advancement of hyperandrogenism symptoms. Patterns of menstruation are examined since irregular patterns may appear with hirsutism. Family history is also assessed for occurrences of hyperandrogenism symptoms or obesity in other family members.
A laboratory test can also be done on the patient to evaluate levels of FSH, LH, DHEAS, prolactin, 17OHP, and total and free testosterone in the patient's blood. Abnormally high levels of any of these hormones help in diagnosing hyperandrogenism.
Unlike tumors of the posterior Pituitary, Pituitary adenomas are classified as endocrine tumors (not brain tumors). Pituitary adenomas are classified based upon anatomical, histological and functional criteria.
- Anatomically pituitary tumors are classified by their size based on radiological findings; either microadenomas (less than <10 mm) or macroadenomas (equal or greater than ≥10 mm).
- Histological classification utilizes an immunohistological characterization of the tumors in terms of their hormone production. Historically they were classed as either basophilic, acidophilic, or chromophobic on the basis of whether or not they took up the tinctorial stains hematoxylin and eosin. This classification has fallen into disuse, in favor of a classification based on what type of hormone is secreted by the tumor. Approximately 20-25% of adenomas do not secrete any readily identifiable active hormones ('non-functioning tumors') yet they are still sometimes referred to as 'chromophobic'.
- Functional classification is based upon the tumors endocrine activity as determined by serum hormone levels and pituitary tissue cellular hormone secretion detected via immunohistochemical staining. The "Percentage of hormone production cases" values are the fractions of adenomas producing each related hormone of each tumor type as compared to all cases of pituitary tumors, and does not directly correlate to the percentages of each tumor type because of smaller or greater incidences of absence of secretion of the expected hormone. Thus, nonsecretive adenomas may be either "null cell adenomas" or a more specific adenoma that, however, remains nonsecretive.
Most XY children are so undervirilized that they are raised as girls. The testes are uniformly nonfunctional and undescended; they are removed when the diagnosis is made due to the risk of cancer development in these tissues.