·
19 All about a hormone which is little discussed :
·
It is known that hyperprolactinaemia can cause galactorrhoea and
irregular cycles or even amenorrhoea. High serum prolactin (PRL) can disturb
follicular maturation and corpus luteum function. Treatment of
hyperprolactinaemia in patients with resulting bleeding anomalies is
established, but the question is how to manage normal cyclic
hyperprolactinaemic women? Studies have shown that in a subgroup of
asymptomatic patients the serum contains mainly high molecular weight form (big
big PRL), which has a low bioactivity, called macroprolactinaemia. It is
evident that macroprolactin does not affect the control of pituitary PRL
secretion via the short loop feedback mechanism or the secretion of
gonadotrophins as does monomeric PRL. Identification of macroprolactinaemia is
therefore clinically important to prevent unnecessary examinations and
inappropriate treatment. Prolactinoma can be associated with
macroprolactinaemia. Performance of pituitary imaging in asymptomatic patients
with hyperprolactinaemia may therefore be justified, but further studies are
needed to evaluate the relation of costs and benefit. An unsolved problem is
the differentiation between inactive and PRL-secreting tumours. Caution should
be exercised concerning medical treatment in unstimulated patients and also in
patients during ovarian stimulation alone or in combination with intrauterine
insemination or in-vitro fertilization. The potential clinical significance of
hyperprolactinaemia/macroprolactinaemia in asymptomatic women must be further
evaluated
·
Abstract
· Purpose of review: This review aims to summarize current
knowledge about prolactin, and outlines recent information that affects the
management of patients with hyperprolactinaemia.
· Recent findings: The actions of prolactin have been
clarified by studies of prolactin-receptor-deficient mice, which have a clear
phenotype of reproductive failure at multiple sites. The treatment of patients
with hyperprolactinaemia or prolactinoma is largely achieved using dopamine
agonist drugs, which induce the shrinkage of pituitary prolactinomas as well as
control of the endocrine syndrome. Recent findings indicate that successful
cabergoline treatment may be able to induce long-term remission, allowing drug
withdrawal in a substantial proportion of patients.
· Summary: At present, dopamine agonist drugs remain the best
treatment for hyperprolactinaemic patients, and can help most affected women
achieve pregnancy. Future work is likely to help understand the basis of
long-term remission in patients with pituitary prolactinomas.
·
·
·
All about Prolactin:-Elevations
in prolactin may cause amenorrhea or galactorrhea. Amenorrhea
with-out galactorrhea is associated with hyperprolactinemia in approximately
15% of women. In patients with both
galactorrhea and amenorrhea, approximately two-thirds will have
hyperprolactinemia; of those, approximately one-third will have a pituitary
adenoma. In more than one-third of women with hyperprolactinemia, a radiologic
abnormality consistent with a microadenoma (> 1cm) is found.
·
Because levels of
thyroid-stimulating hormone (TSH) are sensitive to excessive or deficient
levels of circulating thyroid hormone, and because most disorders of
hyperthyroidism and hypothyroidism are related to dysfunction of the thyroid
gland, TSH levels are used to screen for these disorders. The most common thyroid
abnormalities in women, autoimmune thyroid disorders, represent the combined
effects of the multiple antibodies produced. Severe primary hypothyroidism is
associated with amenorrhea or anovulation. The classic triad of exophthalmos,
goiter, and hyperthyroidism in Graves disease is associated with symptoms of
hyperthyroidism.
The endocrine disorders encountered most frequently
in gynecologic patients are those related to disturbances in the regular
occurrence of ovulation and accompanying menstruation. The most prevalent are
those characterized by androgen excess, often with insulin resistance,
including what is arguably the most common endocrinopathy in women— polycystic
ovary syndrome (PCOS).other conditions leading to ovulatory dysfunction, hirsutism, or
virilization, and common disorders of the pituitary and thyroid glands
associated with reproductive abnormalities,
No comments:
Post a Comment