A comparison of present and old photographs may show gradual changes and is an essential part of the assessment of acromegaly. Musculoskeletal: Generalized weakness and lethargy are common symptoms. Elongation of the jaw can lead to teeth malocclusion, temporomandibular joint pain, and also a characteristic interdental separation. Early-onset osteoarthritis due to incongruent articular surfaces in the hips, knees, and spine may be seen.
Kyphoscoliosis has also been reported in association with acromegaly. Deep voice and obstructive sleep apnea can occur secondary to soft tissue swelling of the upper airway and large tongue. Gigantism is very rare and should be suspected when the patient's height is 3 standard deviations above normal mean height or 2 standard deviations above the adjusted mean parental height. Since gigantism is associated with various syndromes like neurofibromatosis, Carney complex and McCune Albright syndrome, evaluation for neurofibromas with cafe au lait spots, optic gliomas, and skin lentigines should be done.
Biochemical diagnosis: Measurement of IGF-1 level is the initial test for the diagnosis of acromegaly as it is a stable molecule with a half-life of 15 hours. It should be measured in cases where there is clinical suspicion of acromegaly and pituitary masses — normal IGF-1 level rules out acromegaly.
False-positive IGF-1 levels can be seen in pregnancy and adolescence, and false-negative levels may be seen with estrogen therapy. Furthermore, hepatic failure, renal failure, hypothyroidism, malnutrition, sepsis, and poorly controlled diabetes mellitus can also influence IGF-1 levels. Plasma glucose needs to be measured before and after the administration of glucose to make sure hyperglycemia has been achieved.
Imaging: Pituitary Magnetic resonance imaging MRI is the preferred imaging modality for the diagnosis of acromegaly. The size, extent of the tumor, optic chiasmal compression, and cavernous sinus invasion can all be assessed on the MRI scan.
Visual field testing is to be done in all cases where the tumor is in contact with the optic chiasm on the MRI scan. Other tests: Prolactin levels need to be assessed especially in the presence of galactorrhea or symptoms of hypogonadism. Anterior pituitary hormonal assessment needs to be done based on the clinical picture. Rarely, in the presence of normal pituitary and biochemically confirmed acromegaly GHRH levels and imaging of the chest and abdomen need to be done to evaluate for ectopic GH or GHRH secretion.
There are three main modalities available for the treatment of acromegaly each with its advantages and disadvantages: surgery, medical therapy, and radiation.
The decision to use these modalities is made on a case-by-case basis. Surgical excision of the tumor is the preferred initial treatment unless the patient is deemed unfit for surgery. Surgery is also the preferred modality in case of recurrence as long as the tumor remains accessible. The transsphenoidal approach involves accessing the tumor by getting to the sphenoid sinus either through a nasal or sublabial approach and removing the sellar floor.
Even tumors with suprasellar extension can be removed with this approach. Endoscopic transsphenoidal resection has better tumor clearance, decreased morbidity, and complications as compared to the microscopic approach.
Post-surgical complications include diabetes insipidus and anterior pituitary deficiencies. IGF-1 and GH levels need to be measured 12 weeks after surgery. Various medical therapies are available for the management of acromegaly. They are used in the treatment of persistent disease after surgery. Radiation is often used as an adjunct for the treatment of persistent disease after surgery; rarely it may be used as a first-line treatment in patients unfit for surgery.
Two commonly used radiation therapy modalities are external irradiation and stereotactic single high dose irradiation. Acromegaloidism: This is a condition where the patients have acromegaloid facial features or tall stature, however, laboratory assessment of GH and IGF-1 are normal.
Imaging of pituitary in these cases is unremarkable. Soto's syndrome: This is a congenital overgrowth syndrome characterized by tall stature, acromegaloid facies, intellectual disabilities, macrocephaly, and advanced bone age.
Other clinical features include neonatal hypotonia, congenital heart defects, strabismus, scoliosis, and a predisposition to cancer. Soto syndrome is due to haploinsufficiency of NSD1 gene on chromosome 5. Genetic studies are needed to differentiate it from acromegaly. The prognosis depends on the stage at which the diagnosis is made as well as the response of hormone levels to treatment - surgical or non-surgical. Prognathism, enlarged tongue, and soft tissue accumulation in the upper airways all predispose to having OSA.
Clinical assessment Epworth score and if needed polysomnography should be done at baseline and repeated every year. Surgical correction of prognathism may help, and referral to the maxillofacial surgeon should be considered. Both small and large joints are affected. By permission of the publisher. From Newman C. Philadelphia, Current Medicine, In Atlas of Cancer. Gigantism and acromegaly are syndromes of excessive secretion of growth hormone hypersomatotropism that are nearly always due to a pituitary adenoma.
Before closure of the epiphyses, the result is gigantism. Later, the result is acromegaly, which causes distinctive facial and other features. Diagnosis is clinical, by skull and hand x-rays, and by measurement of levels of growth hormone and insulin-like growth factor 1.
Treatment involves removal or destruction of the responsible adenoma, and sometimes also other treatment modalities. Growth hormone GH stimulates somatic growth and regulates metabolism. Growth hormone—releasing hormone GHRH is the major stimulator and somatostatin is the major inhibitor of the synthesis and release of GH.
GH controls synthesis of insulin-like growth factor 1 IGF-1, also called somatomedin-C , which largely controls growth. The metabolic effects of GH are biphasic. GH initially exerts insulin-like effects, increasing glucose uptake in muscle and fat, stimulating amino acid uptake and protein synthesis in liver and muscle, and inhibiting lipolysis in adipose tissue.
Several hours later, more profound anti—insulin-like metabolic effects occur. They include inhibition of glucose uptake and use, causing blood glucose and lipolysis to increase, which increases plasma free fatty acids. GH-secreting tumors are largely sporadic, but genetic abnormalities in the X chromosome X-linked acrogigantism , overexpression of the pituitary tumor transforming gene PTTG , and mutations in the aryl hydrocarbon receptor—interacting protein AIP have been discovered.
Many GH—secreting adenomas contain a mutant form of the Gs protein, which is a stimulatory regulator of adenylate cyclase. A few cases of ectopic GHRH-producing tumors, especially of the pancreas and lung, also have been described. The patient on the right was diagnosed with gigantism as an infant.
She is several feet taller than her mother on the left. This rare condition occurs if GH hypersecretion begins in childhood, before closure of the epiphyses. Skeletal growth velocity and ultimate stature are increased, but little bony deformity occurs.
However, soft-tissue swelling occurs, and the peripheral nerves are enlarged. Delayed puberty Delayed Puberty Delayed puberty is absence of sexual maturation at the expected time.
Diagnosis is by measurement of gonadal hormones testosterone and estradiol , luteinizing hormone, and follicle-stimulating In acromegaly, GH hypersecretion usually starts between the 20s and 40s. When GH hypersecretion begins after epiphyseal closure, the earliest clinical manifestations are coarsening of the facial features and soft-tissue swelling of the hands and feet.
Appearance changes, and larger rings, gloves, and shoes are needed. Photographs of the patient are important in delineating the course of the disease.
This photo shows a patient with frontal bossing, prognathism, nasal bone hypertrophy, and thickened skin. Left image shows a year-old woman who presented with acromegaly due to a pituitary adenoma.
Right image shows the same patient 11 years earlier. Note the change in facial features compared with the left image. Frontal and lateral images of a patient with acromegaly. Coarse facial features are evident, including prognathism and prominence of the malar eminences and supraorbital ridges.
The most common cause of galactorrhea is overproduction of the hormone prolactin hyperprolactinemia About one third of men who have acromegaly develop erectile dysfunction Erectile Dysfunction ED Erectile dysfunction ED is the inability to attain or sustain an erection satisfactory for sexual intercourse. See also Overview of Sexual Dysfunction in Men. Every man occasionally has There is also an increased likelihood of developing diabetes mellitus Diabetes Mellitus DM Diabetes mellitus is a disorder in which the body does not produce enough or respond normally to insulin, causing blood sugar glucose levels to be abnormally high.
Urination and thirst are Often no cause for high blood pressure can be identified, but sometimes it occurs as a result of an underlying Life expectancy is reduced in people with untreated acromegaly. In children, rapid growth may not seem abnormal at first. Eventually, however, the abnormality of the extreme growth becomes clear.
In adults, because the changes induced by high levels of growth hormone occur slowly, acromegaly often is not diagnosed until many years after the first symptoms appear. Serial photographs those taken over many years may help a doctor establish the diagnosis.
Imaging of the skull may show thickening of the bones and enlargement of the nasal sinuses. X-rays of the hands show thickening of the bones under the fingertips and swelling of the tissue around the bones. Computed tomography Computed Tomography CT In computed tomography CT , which used to be called computed axial tomography CAT , an x-ray source and x-ray detector rotate around a person.
In modern scanners, the x-ray detector usually MRI does not use x-rays and is usually very safe Because acromegaly is usually present for some years before being diagnosed, a tumor is seen on these scans in most people. The diagnosis is confirmed by blood tests, which usually show high levels of both growth hormone and insulin -like growth factor 1 IGF Because growth hormone is released in short bursts and the levels of growth hormone often fluctuate dramatically even in people without acromegaly, a single high level of growth hormone in the blood is insufficient to make the diagnosis.
Doctors must give something that would normally suppress growth hormone levels, most commonly a glucose drink the oral glucose tolerance test Oral glucose tolerance test Diabetes mellitus is a disorder in which the body does not produce enough or respond normally to insulin, causing blood sugar glucose levels to be abnormally high.
This test is not necessary when the clinical features of acromegaly are obvious, the IGF-1 level is high, or a tumor is seen in the pituitary on CT or MRI. Stopping or reducing the overproduction of growth hormone is not easy.
Doctors may need to use a combination of surgery, radiation therapy, and drug therapy. Surgery to remove the pituitary tumor by an experienced surgeon is currently regarded as the best first treatment for most people with acromegaly caused by a tumor. It results in an immediate reduction in tumor size and growth hormone production, most often without causing deficiency of other pituitary hormones. Unfortunately, tumors are often large by the time they are found, and surgery alone does not usually cure the disorder.
Because acromegaly is uncommon and the physical changes occur slowly over many years, the condition sometimes takes a long time to recognize. Untreated, high levels of growth hormone can affect other parts of the body, in addition to your bones. This can lead to serious — sometimes even life-threatening — health problems. But treatment can reduce your risk of complications and significantly improve your symptoms, including the enlargement of your features.
A common sign of acromegaly is enlarged hands and feet. For example, you may notice that you aren't able to put on rings that used to fit, and that your shoe size has progressively increased. Acromegaly may also cause gradual changes in your face's shape, such as a protruding lower jaw and brow bone, an enlarged nose, thickened lips, and wider spacing between your teeth.
Because acromegaly tends to progress slowly, early signs may not be obvious for years. Sometimes, people notice the physical changes only by comparing old photos with newer ones. Overall, acromegaly signs and symptoms tend to vary from one person to another, and may include any of the following:. Acromegaly usually develops slowly.
Even your family members may not notice the gradual physical changes that occur with this disorder at first.
But early diagnosis is important so that you can start getting proper care. Acromegaly can lead to serious health problems if it's not treated.
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