Turner syndrome
Turner syndrome or Ullrich-Turner syndrome (also known as "Gonadal dysgenesis”) encompasses several conditions, of which monosomy X (absence of an entire sex chromosome, the Barr body) is most common. It is a chromosomal abnormality in which all or part of one of the sex chromosomes is absent (unaffected humans have 46 chromosomes, of which two are sex chromosomes). Typical females have two X chromosomes, but in Turner syndrome, one of those sex chromosomes is missing or has other abnormalities. In some cases, the chromosome is missing in some cells but not others, a condition referred to as mosaicism[2] or 'Turner mosaicism'.
Occurring in 1 out of every 2500 girls,
There are characteristic physical abnormalities, such as short stature, swelling, broad chest, low hairline, low-set ears, and webbed necks
Girls with Turner syndrome typically experience gonadal dysfunction (non-working ovaries), which results in amenorrhea (absence of menstrual cycle) and sterility. Concurrent health concerns are also frequently present, including congenital heart disease, hypothyroidism (reduced hormone secretion by the thyroid), diabetes, vision problems, hearing concerns, and many autoimmune diseases.[4] Finally, a specific pattern of cognitive deficits is often observed, with particular difficulties in visuospatial, mathematical, and memory areas
Common symptoms of Turner syndrome include:
• Short stature
• Lymphedema (swelling) of the hands and feet
• Broad chest (shield chest) and widely spaced nipples
• Low hairline
• Low-set ears
• Reproductive sterility
• Rudimentary ovaries gonadal streak (underdeveloped gonadal structures)
• Amenorrhoea, or the absence of a menstrual period
• Increased weight, obesity
• Shield shaped thorax of heart
• Shortened metacarpal IV
• Small fingernails
• Characteristic facial features
• Webbed neck from cystic hygroma in infancy
• Coarctation of the aorta
• Bicuspid aortic valve
• Poor breast development
• Horseshoe kidney
• Visual impairments sclera, cornea, glaucoma, etc.
• Ear infections and hearing loss
• High waist-to-hip ratio (the hips are not much bigger than the waist)
• Attention Deficit/Hyperactivity Disorder (problems with concentration, memory and attention)
• Nonverbal Learning Disability (problems with math, social skills and spatial relations)
Women with Turner syndrome are almost universally infertile. While some women with Turner syndrome have successfully become pregnant and carried their pregnancies to term, this is very rare and is generally limited to those women whose karyotypes are not 45,X.[18][19] Even when such pregnancies do occur, there is a higher than average risk of miscarriage or birth defects, including Turner Syndrome or Down Syndrome.[20] Some women with Turner syndrome who are unable to conceive without medical intervention may be able to use IVF or other fertility treatments.[21]
Klinefelter's syndrome
Klinefelter's syndrome, 47, XXY, or XXY syndrome is a condition in which human males have an extra X chromosome. While females have an XX chromosomal makeup, and males an XY, affected individuals have at least two X chromosomes and at least one Y chromosome.[1] Because of the extra chromosome, individuals with the condition are usually referred to as "XXY Males", or "47, XXY Males".[2]
In humans, Klinefelter's syndrome is the most common sex chromosome disorder[3
The condition exists in roughly 1 out of every 1,000 males. One in every 500 males has an extra X chromosome but does not have the syndrome.[4] Other mammals also have the XXY syndrome, including mice
The principal effects are development of small testicles and reduced fertility. A variety of other physical and behavioral differences and problems are common, though severity varies and many boys and men with the condition have few detectable symptoms.
Affected males are almost always effectively infertile, although advanced reproductive assistance is sometimes possible.
The term hypogonadism in XXY symptoms is often misinterpreted to mean "small testicles" or "small penis".
Males with Klinefelter syndrome may have a mosaic 47,XXY/46,XY constitutional karyotype and varying degrees of spermatogenic failure. Mosaicism 47,XXY/46,XX with clinical features suggestive of Klinefelter syndrome is very rare. Thus far, only about 10 cases have been described in literature.[20]
we come in many different colors and flavors (:
Wednesday, September 29, 2010
Wednesday, September 22, 2010
Treatment of hyperthyroidism
The options for treating hyperthyroidism include:
Temporary treatments
• Treating the symptoms
• Antithyroid drugs (Thyrostatics)
Permanent Treatments
• Radioactive iodine
• Surgery treating symptoms
Temporary Treatments
Treating the symptoms
Many of the neurologic and cardiovascular symptoms of thyrotoxicosis are relieved by beta-blocker therapy [propranolol (Inderal), atenolol (Tenormin), metoprolol (Lopressor)]. These medications counteract the effect of thyroid hormone to increase metabolism, but they do not alter the levels of thyroid hormones in the blood. A doctor determines which patients to treat based on a number of variables including the underlying cause of hyperthyroidism, the age of the patient, the size of the thyroid gland, and the presence of coexisting medical illnesses.
Thyrostatics (Antithyroid drugs)
There are two main antithyroid drugs available for use in the US, methimazole (Tapazole) and propylthiouracil (PTU). These drugs accumulate in the thyroid tissue and block production of thyroid hormones. PTU also blocks the conversion of T4(thyroxine) hormone to the more metabolically active T3(triiodothyoinine) hormone. The major risk of these medications is occasional suppression of production of white blood cells by the bone marrow (agranulocytosis).
It is important for patients to know that if they develop a fever, a sore throat, or any signs of infection while taking methimazole or propylthiouracil, they should see a doctor immediately. While a concern, the actual risk of developing agranulocytosis is less than 1%. In general, patients should be seen by the doctor at monthly intervals while taking antithyroid medication. The dose is adjusted to maintain the patient in as close to a normal thyroid state as possible (euthyroid). Once the dosing is stable, patients can be seen at three month intervals if long-term therapy is planned.
Usually, long-term antithyroid therapy is only used for patients with Graves' disease, since this disease may actually go into remission under treatment without requiring treatment with thyroid radiation or surgery. If treated from one to two years, the data shows remission rates of 40%-70%. When the disease is in remission, the gland is no longer overactive, and antithyroid medication is not needed.
Recent studies also have shown that adding a pill of thyroid hormone to the antithyroid medication actually results in higher remission rates. The rationale for this may be that by providing an external source for thyroid hormone, higher doses of antithyroid medications can be given, which may suppress the overactive immune system in persons with Graves' disease. This type of therapy remains controversial, however. When long-term therapy is withdrawn, patients should continue to be seen by the doctor every three months for the first year, since a relapse of Graves' disease is most likely in this time period. If a patient does relapse, antithyroid drug therapy can be restarted, or radioactive iodine or surgery may be considered.
Permanent treatments
Surgery as an option predates the use of the less invasive radioisotope therapy (radioiodine 131 thyroid ablation), but is still required in cases where the thyroid gland is enlarged and causing compression to the neck structures, or the underlying cause of the hyperthyroidism may be cancerous in origin. Some patients suffering from the related condition of thyroid eye disease leading to diplopia because this condition can be worsened by radiotherapy treatment.
Radioactive Iodine
Radioactive iodine is given orally (either by pill or liquid) on a one-time basis to ablate a hyperactive gland. The iodine given for ablative treatment is different from the iodine used in a scan. (For treatment, the isotope iodine 131 is used, while for a routine scan, iodine 123 is used.) Radioactive iodine is given after a routine iodine scan, and uptake of the iodine is determined to confirm hyperthyroidism. The radioactive iodine is picked up by the active cells in the thyroid and destroys them. Since iodine is only picked up by thyroid cells, the destruction is local, and there are no widespread side effects with this therapy.
Radioactive iodine ablation has been safely used for over 50 years, and the only major reasons for not using it are pregnancy and breast-feeding. This form of therapy is the treatment of choice for recurring Graves' disease, patients with severe cardiac involvement, those with multinodular goiter or toxic adenomas, and patients who cannot tolerate antithyroid drugs. Radioactive iodine must be used with caution in patients with Graves' related eye disease since recent studies have shown that the eye disease may worsen after therapy. If a woman chooses to become pregnant after ablation, it is recommended she wait 8-12 months after treatment before conceiving.
In general, more than 80% of patients are cured with a single dose of radioactive iodine. It takes between 8 to 12 weeks for the thyroid to become normal after therapy. Permanent hypothyroidism is the major complication of this form of treatment. While a temporary hypothyroid state may be seen up to six months after treatment with radioactive iodine, if it persists longer than six months, thyroid replacement therapy (with T4 or T3) usually is begun.
Surgery
Surgery to partially remove the thyroid gland (partial thyroidectomy) was once a common form of treatment for hyperthyroidism. The goal is to remove the thyroid tissue that was producing the excessive thyroid hormone. However, if too much tissue is removed, an inadequate production of thyroid hormone (hypothyroidism) may result. In this case, thyroid replacement therapy is begun. The major complication of surgery is disruption of the surrounding tissue, including the nerves supplying the vocal cords and the four tiny glands in the neck that regulate calcium levels in the body (the parathyroid glands). Accidental removal of these glands may result in low calcium levels and require calcium replacement therapy.
With the introduction of radioactive iodine therapy and antithyroid drugs, surgery for hyperthyroidism is not as common as it used to be. Surgery is appropriate for:
• pregnant patients and children who have major adverse reactions to antithyroid medications.
• patients with very large thyroid glands and in those who have symptoms stemming from compression of tissues adjacent to the thyroid, such as difficulty swallowing, hoarseness, and shortness of breath.
Subtotal thyroidectomy is the oldest form of treatment for hyperthyroidism. Total thyroidectomy and combinations of hemithyroidectomies and contralateral subtotal thyroidectomies also have been used.
• Because of excellent effectiveness in regulating thyroid function with antithyroid medications and radioactive iodine, thyroidectomy is reserved for special circumstances, including the following:
o Severe hyperthyroidism in children
o Pregnant women who are noncompliant or intolerant of antithyroid medication
o Patients with very large goiters or severe ophthalmopathy
o Patients who refuse radioactive iodine therapy
o Refractory amiodarone-induced hyperthyroidism
o Patients who require normalization of thyroid functions quickly, such as pregnant women, women who desire pregnancy in the next 6 months, or patients with unstable cardiac conditions
• With current operative techniques, bilateral subtotal thyroidectomy should have a mortality rate approaching zero in patients who are properly prepared. Historically, the most common cause of thyroid storm, a physiologic decompensation in patients who are severely thyrotoxic, with a mortality rate of 50-100%, is operative stress.
• Preoperative preparation includes antithyroid medication, stable (cold) iodine treatment (to decrease gland vascularity), and beta-blocker therapy.5
o Generally, antithyroid drug therapy should be administered until thyroid functions normalize (4-8 wk).
o Titrate propranolol until the resting pulse rate is less than 80 bpm.
o Finally, administer iodide as SSKI (1-2 drops bid for 10-14 d) before surgery.
o An additional benefit from stable iodide therapy, besides the reduction in thyroid hormone excretion, is a demonstrated decrease in thyroid blood flow and possible reduction in blood loss during surgery.
• Adverse effects of therapy include recurrent laryngeal nerve damage and hypoparathyroidism due to damage of local structures during surgery. (A Swiss study indicated that a single dose of steroid administered prior to thyroidectomy can reduce nausea, pain, and vomiting associated with the procedure, as well as improve voice function.
*Ablation means removal of material from the surface of an object by vaporization, chipping, or other erosive processes.
Temporary treatments
• Treating the symptoms
• Antithyroid drugs (Thyrostatics)
Permanent Treatments
• Radioactive iodine
• Surgery treating symptoms
Temporary Treatments
Treating the symptoms
Many of the neurologic and cardiovascular symptoms of thyrotoxicosis are relieved by beta-blocker therapy [propranolol (Inderal), atenolol (Tenormin), metoprolol (Lopressor)]. These medications counteract the effect of thyroid hormone to increase metabolism, but they do not alter the levels of thyroid hormones in the blood. A doctor determines which patients to treat based on a number of variables including the underlying cause of hyperthyroidism, the age of the patient, the size of the thyroid gland, and the presence of coexisting medical illnesses.
Thyrostatics (Antithyroid drugs)
There are two main antithyroid drugs available for use in the US, methimazole (Tapazole) and propylthiouracil (PTU). These drugs accumulate in the thyroid tissue and block production of thyroid hormones. PTU also blocks the conversion of T4(thyroxine) hormone to the more metabolically active T3(triiodothyoinine) hormone. The major risk of these medications is occasional suppression of production of white blood cells by the bone marrow (agranulocytosis).
It is important for patients to know that if they develop a fever, a sore throat, or any signs of infection while taking methimazole or propylthiouracil, they should see a doctor immediately. While a concern, the actual risk of developing agranulocytosis is less than 1%. In general, patients should be seen by the doctor at monthly intervals while taking antithyroid medication. The dose is adjusted to maintain the patient in as close to a normal thyroid state as possible (euthyroid). Once the dosing is stable, patients can be seen at three month intervals if long-term therapy is planned.
Usually, long-term antithyroid therapy is only used for patients with Graves' disease, since this disease may actually go into remission under treatment without requiring treatment with thyroid radiation or surgery. If treated from one to two years, the data shows remission rates of 40%-70%. When the disease is in remission, the gland is no longer overactive, and antithyroid medication is not needed.
Recent studies also have shown that adding a pill of thyroid hormone to the antithyroid medication actually results in higher remission rates. The rationale for this may be that by providing an external source for thyroid hormone, higher doses of antithyroid medications can be given, which may suppress the overactive immune system in persons with Graves' disease. This type of therapy remains controversial, however. When long-term therapy is withdrawn, patients should continue to be seen by the doctor every three months for the first year, since a relapse of Graves' disease is most likely in this time period. If a patient does relapse, antithyroid drug therapy can be restarted, or radioactive iodine or surgery may be considered.
Permanent treatments
Surgery as an option predates the use of the less invasive radioisotope therapy (radioiodine 131 thyroid ablation), but is still required in cases where the thyroid gland is enlarged and causing compression to the neck structures, or the underlying cause of the hyperthyroidism may be cancerous in origin. Some patients suffering from the related condition of thyroid eye disease leading to diplopia because this condition can be worsened by radiotherapy treatment.
Radioactive Iodine
Radioactive iodine is given orally (either by pill or liquid) on a one-time basis to ablate a hyperactive gland. The iodine given for ablative treatment is different from the iodine used in a scan. (For treatment, the isotope iodine 131 is used, while for a routine scan, iodine 123 is used.) Radioactive iodine is given after a routine iodine scan, and uptake of the iodine is determined to confirm hyperthyroidism. The radioactive iodine is picked up by the active cells in the thyroid and destroys them. Since iodine is only picked up by thyroid cells, the destruction is local, and there are no widespread side effects with this therapy.
Radioactive iodine ablation has been safely used for over 50 years, and the only major reasons for not using it are pregnancy and breast-feeding. This form of therapy is the treatment of choice for recurring Graves' disease, patients with severe cardiac involvement, those with multinodular goiter or toxic adenomas, and patients who cannot tolerate antithyroid drugs. Radioactive iodine must be used with caution in patients with Graves' related eye disease since recent studies have shown that the eye disease may worsen after therapy. If a woman chooses to become pregnant after ablation, it is recommended she wait 8-12 months after treatment before conceiving.
In general, more than 80% of patients are cured with a single dose of radioactive iodine. It takes between 8 to 12 weeks for the thyroid to become normal after therapy. Permanent hypothyroidism is the major complication of this form of treatment. While a temporary hypothyroid state may be seen up to six months after treatment with radioactive iodine, if it persists longer than six months, thyroid replacement therapy (with T4 or T3) usually is begun.
Surgery
Surgery to partially remove the thyroid gland (partial thyroidectomy) was once a common form of treatment for hyperthyroidism. The goal is to remove the thyroid tissue that was producing the excessive thyroid hormone. However, if too much tissue is removed, an inadequate production of thyroid hormone (hypothyroidism) may result. In this case, thyroid replacement therapy is begun. The major complication of surgery is disruption of the surrounding tissue, including the nerves supplying the vocal cords and the four tiny glands in the neck that regulate calcium levels in the body (the parathyroid glands). Accidental removal of these glands may result in low calcium levels and require calcium replacement therapy.
With the introduction of radioactive iodine therapy and antithyroid drugs, surgery for hyperthyroidism is not as common as it used to be. Surgery is appropriate for:
• pregnant patients and children who have major adverse reactions to antithyroid medications.
• patients with very large thyroid glands and in those who have symptoms stemming from compression of tissues adjacent to the thyroid, such as difficulty swallowing, hoarseness, and shortness of breath.
Subtotal thyroidectomy is the oldest form of treatment for hyperthyroidism. Total thyroidectomy and combinations of hemithyroidectomies and contralateral subtotal thyroidectomies also have been used.
• Because of excellent effectiveness in regulating thyroid function with antithyroid medications and radioactive iodine, thyroidectomy is reserved for special circumstances, including the following:
o Severe hyperthyroidism in children
o Pregnant women who are noncompliant or intolerant of antithyroid medication
o Patients with very large goiters or severe ophthalmopathy
o Patients who refuse radioactive iodine therapy
o Refractory amiodarone-induced hyperthyroidism
o Patients who require normalization of thyroid functions quickly, such as pregnant women, women who desire pregnancy in the next 6 months, or patients with unstable cardiac conditions
• With current operative techniques, bilateral subtotal thyroidectomy should have a mortality rate approaching zero in patients who are properly prepared. Historically, the most common cause of thyroid storm, a physiologic decompensation in patients who are severely thyrotoxic, with a mortality rate of 50-100%, is operative stress.
• Preoperative preparation includes antithyroid medication, stable (cold) iodine treatment (to decrease gland vascularity), and beta-blocker therapy.5
o Generally, antithyroid drug therapy should be administered until thyroid functions normalize (4-8 wk).
o Titrate propranolol until the resting pulse rate is less than 80 bpm.
o Finally, administer iodide as SSKI (1-2 drops bid for 10-14 d) before surgery.
o An additional benefit from stable iodide therapy, besides the reduction in thyroid hormone excretion, is a demonstrated decrease in thyroid blood flow and possible reduction in blood loss during surgery.
• Adverse effects of therapy include recurrent laryngeal nerve damage and hypoparathyroidism due to damage of local structures during surgery. (A Swiss study indicated that a single dose of steroid administered prior to thyroidectomy can reduce nausea, pain, and vomiting associated with the procedure, as well as improve voice function.
*Ablation means removal of material from the surface of an object by vaporization, chipping, or other erosive processes.
Investigation of Grave’s Disease
Laboratory Tests
BLOOD TESTS Thyroid Function Test
1. Ultrasensitive TSH test
a. Detects even tiny amounts of TSH in the blood
b. High TSH indicates thyroid gland is failing because ofproblem that is directly affecting throud (Primary hypothyroidism)
c. Low TSH indicares overactive thyroid that producing too much thyroid (Hyperthyroidism)
d. Low TSH: abnormal pituitary gland that prevents it from making enough TSH to stimulate thyroid (secondary hypothyroidism)
2. T4/throxine test [Free T4 (Ft4) or Free T4 Index (FT4I or FTI)]
a. Circulates in the blood in 2 forms: bound to proteins that prevent the T4 from entering tissues/ free T4 that enter tissues freely
b. Free T4 fraction determine how the thyroid is functioning
c. High FT4/FTI hyperthyroidism; low hypothyroidism
d. elevated TSH and low FT4 or FTI indicates primary hypothyroidism due to disease in the thyroid gland.
e. A low TSH and low FT4 or FTI indicates hypothyroidism due to a problem involving the pituitary gland.
f. A low TSH with an elevated FT4 or FTI is found in individuals who have hyperthyroidism.
3. T3/triiodothyronine test
a. to diagnosis hyperthyroidism or to determine the severity of the hyperthyroidism.
b. High T3 = hyperthyroid
4. Thyroid-stimulating immunoglobulin test (TSH antibody test)
a. Isn’t necessary to diagnose Grave’s
b. Most people with Grave’s have this antibody, but people with other hyperthyroidism do not.
c. 2 antibodies: throid peroxidase and thyroglobulin
d. Anti_thyroid peroxidase (anti-TPO): Autoantibody that found in most people with Grave’s disease, as well as in Hashimptp’s thyroiditis.
Imaging Tests
1. The radioactive iodine uptake test (RAIU)
o Thyroid gland uses iodine to make thyroid hormone (T4)
o Measures the amount of iodine the thyroid collects from the bloodstream. High levels of iodine uptake can indicate hyperthyroidism, eg. Graves’ disease.
o A thyroid scan shows how and where iodine is distributed in the thyroid. In Graves’ disease, the entire thyroid gland is involved so the iodine shows up throughout the gland. Other causes of hyperthyroidism such as nodules—small lumps in the gland—will show a different pattern of iodine distribution.
2. Ultrasond with color-Doppler evaluation
o Cost effective
o 1st step in all hyperthyroid patients
References:
http://www.endocrine.niddk.nih.gov/pubs/graves/
http://www.thyroid.org/patients/brochures/Graves_brochure.pdf
http://www.labtestsonline.org/understanding/conditions/graves-2.html
http://emedicine.medscape.com/article/120619-diagnosis
http://www.thyroid.org/patients/brochures/FunctionTests_brochure.pdf
BLOOD TESTS Thyroid Function Test
1. Ultrasensitive TSH test
a. Detects even tiny amounts of TSH in the blood
b. High TSH indicates thyroid gland is failing because ofproblem that is directly affecting throud (Primary hypothyroidism)
c. Low TSH indicares overactive thyroid that producing too much thyroid (Hyperthyroidism)
d. Low TSH: abnormal pituitary gland that prevents it from making enough TSH to stimulate thyroid (secondary hypothyroidism)
2. T4/throxine test [Free T4 (Ft4) or Free T4 Index (FT4I or FTI)]
a. Circulates in the blood in 2 forms: bound to proteins that prevent the T4 from entering tissues/ free T4 that enter tissues freely
b. Free T4 fraction determine how the thyroid is functioning
c. High FT4/FTI hyperthyroidism; low hypothyroidism
d. elevated TSH and low FT4 or FTI indicates primary hypothyroidism due to disease in the thyroid gland.
e. A low TSH and low FT4 or FTI indicates hypothyroidism due to a problem involving the pituitary gland.
f. A low TSH with an elevated FT4 or FTI is found in individuals who have hyperthyroidism.
3. T3/triiodothyronine test
a. to diagnosis hyperthyroidism or to determine the severity of the hyperthyroidism.
b. High T3 = hyperthyroid
4. Thyroid-stimulating immunoglobulin test (TSH antibody test)
a. Isn’t necessary to diagnose Grave’s
b. Most people with Grave’s have this antibody, but people with other hyperthyroidism do not.
c. 2 antibodies: throid peroxidase and thyroglobulin
d. Anti_thyroid peroxidase (anti-TPO): Autoantibody that found in most people with Grave’s disease, as well as in Hashimptp’s thyroiditis.
Imaging Tests
1. The radioactive iodine uptake test (RAIU)
o Thyroid gland uses iodine to make thyroid hormone (T4)
o Measures the amount of iodine the thyroid collects from the bloodstream. High levels of iodine uptake can indicate hyperthyroidism, eg. Graves’ disease.
o A thyroid scan shows how and where iodine is distributed in the thyroid. In Graves’ disease, the entire thyroid gland is involved so the iodine shows up throughout the gland. Other causes of hyperthyroidism such as nodules—small lumps in the gland—will show a different pattern of iodine distribution.
2. Ultrasond with color-Doppler evaluation
o Cost effective
o 1st step in all hyperthyroid patients
References:
http://www.endocrine.niddk.nih.gov/pubs/graves/
http://www.thyroid.org/patients/brochures/Graves_brochure.pdf
http://www.labtestsonline.org/understanding/conditions/graves-2.html
http://emedicine.medscape.com/article/120619-diagnosis
http://www.thyroid.org/patients/brochures/FunctionTests_brochure.pdf
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