Sandbox:Aditya: Difference between revisions
Aditya Ganti (talk | contribs) |
Aditya Ganti (talk | contribs) |
||
Line 659: | Line 659: | ||
| | | | ||
|} | |} | ||
===Pathophysiology=== | |||
*Schistosomes have a typical trematode vertebrate-invertebrate lifecycle, with humans being the definitive host. | |||
*The life cycles of all five human schistosomes are broadly similar | |||
*Parasite eggs are released into the environment from infected individuals, hatching on contact with fresh water to release the free-swimming [[miracidium]]. | |||
*Miracidia infect fresh-water snails by penetrating the snail's foot. | |||
*After infection, close to the site of penetration, the miracidium transforms into a primary (mother) sporocyst. | |||
*Germ cells within the primary sporocyst will then begin dividing to produce secondary (daughter) sporocysts, which migrate to the snail's hepatopancreas. | |||
*Once at the hepatopancreas, germ cells within the secondary sporocyst begin to divide again, this time producing thousands of new parasites, known as cercariae, which are the larvae capable of infecting mammals. | |||
*Cercariae emerge daily from the snail host in a [[circadian]] rhythm, dependent on ambient temperature and light. | |||
*Young cercariae are highly motile, alternating between vigorous upward movement and sinking to maintain their position in the water. | |||
*Cercarial activity is particularly stimulated by water turbulence, by shadows and by chemicals found on human skin. | |||
*Penetration of the human skin occurs after the cercaria have attached to and explored the skin. | |||
*The parasite secretes enzymes that break down the skin's protein to enable penetration of the cercarial head through the skin. | |||
*As the cercaria penetrates the skin it transforms into a migrating schistosomulum stage. | |||
*The newly transformed schistosomulum may remain in the skin for 2 days before locating a post-capillary [[venule]] from here the schistosomulum travels to the lungs where it undergoes further developmental changes necessary for subsequent migration to the liver. | |||
*Eight to ten days after penetration of the skin, the parasite migrates to the [[liver sinusoid]]s. | |||
*''S. japonicum'' migrates more quickly than S. mansoni, and usually reaches the liver within 8 days of penetration. | |||
*Juvenile ''S. mansoni'' and ''S. japonicum'' worms develop an oral sucker after arriving at the liver, and it is during this period that the parasite begins to feed on red blood cells. | |||
*The nearly-mature worms pair, with the longer female worm residing in the gynaecophoric channel of the male. | |||
*Adult worms are about 10 mm long. Worm pairs of S. mansoni and S. japonicum relocate to the [[mesenteric]] or rectal veins. | |||
*''S. haematobium'' schistosomula ultimately migrate from the liver to the perivesical venous plexus of the bladder, ureters, and kidneys through the hemorrhoidal plexus. | |||
*Parasites reach maturity in six to eight weeks, at which time they begin to produce eggs. | |||
*Adult ''S. mansoni'' pairs residing in the mesenteric vessels may produce up to 300 eggs per day during their reproductive lives. | |||
*''S. japonicum'' may produce up to 3000 eggs per day. Many of the eggs pass through the walls of the blood vessels, and through the intestinal wall, to be passed out of the body in faeces. | |||
*''S. haematobium'' eggs pass through the ureteral or bladder wall and into the urine. Only mature eggs are capable of crossing into the digestive tract, possibly through the release of [[proteolytic]] enzymes, but also as a function of host immune response, which fosters local tissue ulceration. | |||
*Up to half the eggs released by the worm pairs become trapped in the mesenteric veins, or will be washed back into the liver, where they will become lodged. | |||
*Worm pairs can live in the body for an average of four and a half years but may persist up to 20 years. | |||
*Trapped eggs mature normally, secreting [[antigens]] that elicit a vigorous [[immune]] response. | |||
*The eggs themselves do not damage the body. Rather it is the cellular infiltration resultant from the immune response that causes the pathology classically associated with schistosomiasis. | |||
==References== | ==References== | ||
{{reflist|2}} | {{reflist|2}} |
Revision as of 18:32, 7 August 2017
Epidemiology
Incidence
United States The prevalence of Addison disease is 40-60 cases per 1 million population.
Mortality/Morbidity
Morbidity and mortality associated with Addison disease usually are due to failure or delay in making the diagnosis or a failure to institute adequate glucocorticoid and mineralocorticoid replacement. [6] If not treated promptly, acute addisonian crisis may result in death. This may be provoked either de novo, such as by adrenal hemorrhage, or in the setting of an acute event superimposed on chronic or inadequately treated adrenocortical insufficiency. With slow-onset chronic Addison disease, significant low-level, nonspecific, but debilitating, symptomatology may occur. Even after diagnosis and treatment, the risk of death is more than 2-fold higher in patients with Addison disease. Cardiovascular, malignant, and infectious diseases are responsible for the higher mortality rate. [7] White and Arlt examined the prevalence of and risk factors for adrenal crisis in patients with Addison disease, utilizing a survey of Addison patients in the United Kingdom, Canada, Australia, and New Zealand. The authors' results indicated that approximately 8% of patients diagnosed with Addison disease require annual hospital treatment for adrenal crisis. In addition, the investigators concluded that exposure to gastric infection is the most important risk factor for adrenal crisis in the presence of Addison disease; diabetes and/or asthma [8] concomitant with Addison disease also increase the risk, according to White and Arlt. [9] A study by Chantzichristos et al indicated that in patients with type 1 or 2 diabetes, those who also have Addison disease have a higher mortality rate than do those with diabetes alone. Over a median follow-up period of 5.9 years, the mortality rate for diabetes patients with Addison disease was 28%, compared with 10% for those without Addison disease. The increase in the estimated relative overall mortality risk was 3.89 for the Addison disease patients compared with the other group. Although cardiovascular deaths accounted for the highest mortality rate in both groups, the death rate from diabetes complications, infectious diseases, and unknown causes was greater in the patients with Addison disease than in those with diabetes alone. [10]
Race
Addison disease is not associated with a racial predilection.
Sex
Idiopathic autoimmune Addison disease tends to be more common in females and children.
Age
The most common age at presentation in adults is 30-50 years, but the disease could present earlier in patients with any of the polyglandular autoimmune syndromes, congenital adrenal hyperplasia (CAH), or if onset is due to a disorder of long-chain fatty acid metabolism.
Historical perspective
Classification
Adrenal insufficiency disorders may be classified into acute and chronic forms, depending on the timing of presentation and duration and into primary and secondary, depending on the etiology of adrenal insufficiency.
Based on the duration of symptoms
Acute adrenal insufficiency
- Adrenal crisis
Chronic adrenal insufficiency
- Chronic primary adrenal insufficiency
- Chronic secondary adrenal insufficiency
Based on etiology
Primary adrenal insufficiency(Addisons disease)
- Anatomic destruction of the adrenal gland
- Infection (TB)
- Congenital adrenal hyperplasia
Secondary adrenal insufficiency
- Hypothalamic-pituitary axis suppression
Pathology
Cortisol is normally produced by the adrenal glands, which are located just above the kidneys. It belongs to a class of hormones called glucocorticoids, which affect almost every organ and tissue in the body. Scientists think that cortisol possibly has hundreds of effects in the body. Cortisol's most important job is to help the body respond to stress. Among its other vital tasks, cortisol;
Helps maintain blood pressure and cardiovascular function Helps slow the immune system's inflammatory response Helps balance the effects of insulin in breaking down sugar for energy Helps regulate the metabolism of proteins, carbohydrates, and fats Helps maintain proper arousal and sense of well-being Because cortisol is so vital to health, the amount of cortisol produced by the adrenals is precisely balanced. Like many other hormones, cortisol is regulated by the brain's hypothalamus and the pituitary gland, a bean-sized organ at the base of the brain. First, the hypothalamus sends "releasing hormones" to the pituitary gland. The pituitary responds by secreting hormones that regulate growth, thyroid function, adrenal function, and sex hormones such as estrogen and testosterone. One of the pituitary's main functions is to secrete ACTH (adrenocorticotropin), a hormone that stimulates the adrenal glands. When the adrenals receive the pituitary's signal in the form of ACTH, they respond by producing cortisol. Completing the cycle, cortisol then signals the pituitary to lower secretion of ACTH.
Aldosterone Aldosterone belongs to a class of hormones called mineralocorticoids, also produced by the adrenal glands. It helps maintain blood pressure and water and salt balance in the body by helping the kidney retain sodium and excrete potassium. When aldosterone production falls too low, the kidneys are not able to regulate salt and water balance, causing blood volume and blood pressure to drop.
Laboratory
Evaluating a patient with suspected adrenal insufficiency is a three-step process: establishing the diagnosis, differentiating between primary and secondary adrenal insufficiencies, and looking for the cause of adrenal insufficiency.
8 am cortisol | |||||||||||||||||||||||||||||||||||||||||||
>15Ug/dL | 3-15Ug/dL | <3Ug/dL | |||||||||||||||||||||||||||||||||||||||||
Adrenal insufficiency is ruled out | Measure ACTH | ||||||||||||||||||||||||||||||||||||||||||
30 min cortisol during cosyntropin stimulation test | |||||||||||||||||||||||||||||||||||||||||||
>18Ug/dL | <18Ug/dL | ||||||||||||||||||||||||||||||||||||||||||
Adrenal insufficiency is ruled out | |||||||||||||||||||||||||||||||||||||||||||
Adrenal insufficiency confirmed | |||||||||||||||||||||||||||||||||||||||||||
Measure ACTH | |||||||||||||||||||||||||||||||||||||||||||
Low/normal | Elevated | ||||||||||||||||||||||||||||||||||||||||||
Secondary Adrenal insufficiency | Primary Adrenal insufficiency | ||||||||||||||||||||||||||||||||||||||||||
Medical therapy
Adrenal crisis=
Supportive Therapy
- IV access should be established immediately with an infusion of isotonic sodium chloride solution should be begun to restore volume deficit and correct hypotension.
Mecial Management
- Preferred regimen (1): Dexamethasone sodium phosphate 4 mg iv q24h
- Preferred regimen (2): Hydrocortisone sodium succinate 50-100 mg iv q8h
- Note: Infusion may be initiated with 100 mg of hydrocortisone as an IV bolus with saline and infuse over 24 h to avoid needing to renew the infusion every 8-10 hours.
The infusion method maintains plasma cortisol levels more adequately at steady stress levels, especially in the small percentage of patients who are rapid metabolizers and who may have low plasma cortisol levels between the IV boluses. Clinical improvement, especially blood pressure response, should be evident within 4-6 hours of hydrocortisone infusion. Otherwise, the diagnosis of adrenal insufficiency would be questionable. After 2-3 days, the stress hydrocortisone dose should be reduced to 100-150 mg, infused over a 24-hour period, irrespective of the patient's clinical status. This is to avoid stress gastrointestinal bleeding. As the patient improves and as the clinical situation allows, the hydrocortisone infusion can be gradually tapered over the next 4-5 days to daily replacement doses of approximately 3 mg/h (72-75 mg over 24 h) and eventually to daily oral replacement doses, when oral intake is possible. As long as the patient is receiving 100 mg or more of hydrocortisone in 24 hours, no mineralocorticoid replacement is necessary. The mineralocorticoid activity of hydrocortisone in this dosage is sufficient. Thereafter, as the hydrocortisone dose is weaned further, mineralocorticoid replacement should be instituted in doses equivalent to the daily adrenal gland aldosterone output of 0.05-0.20 mg every 24 hours. The usual mineralocorticoid used for this purpose is 9-alpha-fludrocortisone, usually in doses of 0.05-0.10 mg per day or every other day. Patients may need to be advised to increase salt intake in hot weather.
hese drugs are used for replacement therapy in Addison disease and secondary adrenocortical insufficiency. [3, 4] Prednisone (Deltasone, Sterapred, Orasone)
View full drug information Used for glucocorticoid hormone replacement. Longer acting than hydrocortisone, with a biologic half-life of 18-36 h. Fludrocortisone (Florinef)
View full drug information Synthetic adrenocortical steroid with very potent mineralocorticoid activity. For use in Addison disease and states of aldosterone deficiency. Hydrocortisone sodium succinate or phosphate (Cortef, Hydrocortone)
View full drug information Drug of choice for steroid replacement in acute adrenal crisis and for daily maintenance in patients with Addison disease or secondary adrenocortical insufficiency. Has both glucocorticoid and mineralocorticoid properties. Biologic half-life is 8-12 h. Easiest way to set up infusion is to have pharmacy mix 100 mg of hydrocortisone in 100 mL of 0.9 saline.
Surgery
Parenteral steroid coverage should be used in times of major stress, trauma, or surgery and during any major procedure. During surgical procedures, 100 mg of hydrocortisone should be given, preferably by the IM route, prior to the start of a continuous IV infusion. The IM dose of hydrocortisone assures steroid coverage in case of problems with the IV access. When continuous IV infusion is not practical, an intermittent IV bolus injection every 6-8 hours may be used. After the procedure, the hydrocortisone may be rapidly tapered within 24-36 hours to the usual replacement doses, or as gradually as the clinical situation dictates. Mineralocorticoid replacement usually can be withheld until the patient resumes daily replacement steroids. Addison’s disease (also known as primary adrenal insufficiency or hypoadrenalism) is a rare disorder of the adrenal glands. It affects the production of two essential hormones called cortisol and aldosterone.
PCOS
Historical Perspective
PCOS was first described in 1935 by American gynecologists Irving F. Stein, Sr. and Michael L. Leventhal, from whom its original name of Stein–Leventhal syndrome is taken. The earliest published description of PCOS was in 1721 in Italy. Cyst-related changes to the ovaries were described in 1844.
- In 1721, a description symptoms resembling PCOS was published in Italy
- In 1844, Cyst-related changes to the ovaries were first described.
- In 1935, Irving F. Stein, Sr. and Michael L. Leventhal, American gynecologists, described PCOS for the first time.
Pathophysiology
- The pathophysiology of PCOS is not well understood. There are several organ systems involved in the pathogenesis of PCOS like ovary, adrenal, hypothalamus, pituitary, or insulin-sensitive tissues. It is possible that there are subsets of women with PCOS wherein each of these proposed mechanisms serves as the primary defect.
- Insulin resistance leads to compensatory insulin hypersecretion by the pancreas in order to maintain normoglycemia.
- The resulting hyperinsulinemia promotes ovarian androgen output and may also promote adrenal androgen output.
- High insulin levels also suppress hepatic production of sex hormone binding globulin (SHBG), which exacerbates hyperandrogenemia by increasing the proportion of free circulating androgens.
- Another factor that promotes ovarian androgen output is the fact that women with PCOS are exposed long term to high levels of LH.
- This LH excess seems to be a result of an increased frequency of gonadotropin releasing hormone pulses from the hypothalamus.
- The abnormal hormonal milieu also probably contributes to incomplete follicular development which results in polycystic ovarian morphology.
↑ 5α-reductase reductivity | ↓ Hβ-HSD1 activity | ||||||||||||||||||||||||||||||||||||||
↑ Cortisol metabolism | |||||||||||||||||||||||||||||||||||||||
↑ ACTH | |||||||||||||||||||||||||||||||||||||||
↑ Adrenal androgens | Normal serum cortisol | ||||||||||||||||||||||||||||||||||||||
PCOS | |||||||||||||||||||||||||||||||||||||||
Risk Factors
Common risk factors in the development of polycystic ovary syndrome are
- Hyperinsulinemia secondary to insulin resistance; associated with type 2 diabetes mellitus[1]
- Obesity
- Family history of PCOS among first-degree relatives
Associated Conditions
Common conditions associated with PCOS are
- Type 2 diabetes
- Endometrial hyperplasia and cancer
- Infertility
- Hypertension
- Gestational diabetes
- Preeclampsia
- Hirsutism
- Acne
History
Obtaining the history is the most important aspect of making a diagnosis of PCOS. It provides insight into the cause, precipitating factors and associated comorbid conditions.
- Menstrual abnormalities
- Infertility
- Signs of virilization on physical examination
- Family history of PCOS among first-degree relatives
Symptoms
The most common symptoms of PCOS include
- Amenorrhea or oligomenorrhea
- Abnormal uterine bleeding
- Androgenization, including hirsutism (often slowly progressive), acne, oily skin (common)
- Polycystic ovaries, with or without ovarian enlargement
- Insulin resistance
- Endometrial hyperplasia
Laboratory Findings
Measurement of the plasma levels of several hormones is helpful in supporting the diagnosis of PCOS and especially in excluding other disorders. Determining the LH/FSH ratio of 3:1 is virtually diagnostic of PCOS; however, a normal ratio does not exclude the diagnosis, as LH levels fluctuate widely throughout the course of a day. Other androgens are measured to screen for other virilizing adrenal tumors. Fasting blood glucose is measured to look for diabetes; screening for lipid abnormalities is also employed. Testosterone is measured to exclude a virilizing tumor. Prolactin is measured to exclude a prolactinoma. Thyroid-stimulating hormone (TSH) is measured to rule out hypothyroidism
Harmone | Normal value | PCOS Laboratory Findings | |
---|---|---|---|
LH/FSH ratio | <3;1 | A ratio >3:1 is indicative of PCOS | |
Testosterone | Free: 100 to 200 pg/dL
Total: 20 to 80 ng/dL |
An elevated free testosterone level (200-400 pg/dL) is suggestive of PCOS, | |
Prolactin | 3.8 to 23.2 μg/L | A level >300 μg/L is virtually diagnostic of prolactinoma. | |
TSH | 0.4 to 4.2 mIU/L | Levels are normal in patients with PCOS | |
Androgens | Sex hormone–binding globulin | 1.5 to 2.0 μg/mL | Decreased |
Androstenedione | 75 to 205 ng/dL | Increased | |
Estrone: | 1.5 to 25.0 pg/mL | Increased | |
Dehydroepiandrosterone sulfate | 50 to 450 μg/dL | Increased but are <800 μg/dL | |
17-Hydroxyprogesterone (follicular phase) | 15 to 70 ng/dL | Normal | |
Fasting blood glucose | <110 mg/dL | >126mg/dL Indicates DM |
Ultrasound findings
Typical ultrasound findings in patients with PCOS include
- Two- to 5-fold ovarian enlargement
- Thickened stroma (tunica albuginea)
- Thecal hyperplasia with an increase in stromal content
- Multiple (12+) subcapsular follicles ranging from 2 to 9 mm in diameter ('pearl necklace' appearance)
- Hyperplastic endometrium despite low estrogen production (due to high estrone production from the increased circulating androgens and lack of opposition by progesterone)
Epidemiology and demographics
Prevalence
- Approximately 5% to 10% of women of reproductive age are affected
- Prevalence among first-degree relatives of patients with PCOS is 25% to 50%, suggesting a strong inheritance of the syndrome; there is evidence for possible X-linked dominant transmission
Demographics
Age
- PCOS can appear anytime from menarche until menopause but generally is seen around menarche and is diagnosed then or in early adulthood
Differentiating PCOS from other diseases
Disease | Differentiating Features |
---|---|
Pregnancy |
|
Hypothalamic amenorrhea |
|
Primary amenorrhea |
|
Cushing syndrome |
|
Hyperprolactinemia |
|
Ovarian or adrenal tumor |
|
Congenital adrenal hyperplasia |
|
Anabolic steroid abuse |
|
Hirsutism |
|
Complications
- Endometrial hyperplasia
- Endometrial cancer
- Type 2 diabetes and its microvascular and macrovascular complications
Prognosis
- The prognosis for fertility is very good with treatment. With careful follow-up, ovarian hyperstimulation, multiple pregnancy, and endometrial hyperplasia can be avoided
- Patients should be counseled regarding the long-term risk of diabetes, hypertension, and endometrial hyperplasia, including the importance of maintaining a BMI <25 kg/m2and control of type 2 diabetes.
Diagnostic Criteria
Two definitions are commonly used:
- In 1990 a consensus workshop sponsored by the NIH/NICHD suggested that a patient has PCOS if she has
- Signs of androgen excess (clinical or biochemical)
- Oligoovulation
- Other entities are excluded that would cause polycystic ovaries.
- In 2003 a consensus workshop sponsored by ESHRE/ASRM in Rotterdam indicated PCOS to be present if 2 out of 3 criteria are met: [2]
- Oligoovulation and/or anovulation
- Excess androgen activity
- Polycystic ovaries (by gynecologic ultrasound), and other causes of PCOS are excluded.
The Rotterdam definition is wider, including many more patients, notably patients without androgen excess, whereas in the NIH/NICHD definition androgen excess is a prerequisite. Critics maintain that findings obtained from the study of patients with androgen excess cannot necessarily be extrapolated to patients without androgen excess.
Surgery
Surgery is not considered first-line therapy for PCOS and it does not affect insulin resistance or obesity
Indication
Surgery is indicated in the treatment of PCOS only in patients desiring fertility in whom at least 1 year of conservative therapy has failed
Surgial options
Ovarian drilling
- Laparoscopic surgery that uses a laser or electrosurgical needle to puncture a number of small follicles visible on the surface of the ovary, which are presumably the source of hormone production
Complications
- Bleeding and/or infection
- Postoperative adhesions
Medical Therapy
The first step in the management of PCOS is weight loss if the patient is obese, and treatment of type 2 diabetes, if present, with metformin. In significantly overweight patients, weight loss alone usually effects a cure and should always be vigorously attempted. Diet and exercise are recommended in all women with PCOS. The next step is initiation of treatment to break the self-perpetuating anovulatory cycling, either by stimulating ovulation or suppressing androgenic and ovarian activity. The selection of treatment depends on whether pregnancy is desired. All antiandrogen treatments will take at least 3 months to affect hirsutism. The goals of treatment are:
- Exclude androgen-secreting tumors, endometrial tumors, and endometrial hyperplasia
- Reduce ovarian androgen secretion and/or antagonist activity at target tissues
- Interrupt the self-sustaining abnormal hormonal cycle
- Normalize the endometrium
- Restore fertility by correcting anovulation, if desired
- Reduce insulin resistance
Medical Management
If fertility is not desired
- Preferred regimen (1): Combined oral contraceptive pills one tablet of formulations containing 30 to 35 μg estrogen orally daily for 21 days, then nothing for 7 days
- Preferred regimen (2): Progesterone-only contraceptive pills (eg, norethindrone , norgestrel ) are the treatment of choice if combined oral contraceptive pills are contraindicated
- Alternative regimen(1): Medroxyprogesterone may be used, although it is not approved by the U.S. Food and Drug Administration (FDA) for this indication
- Alternative regimen(2): Glucocorticoids (eg, hydrocortisone , cortisone , dexamethasone ) may be used to suppress adrenal androgen production, although they are not approved by the FDA for this indication
- Alternative regimen(3): Spironolactone and flutamide are androgen receptor antagonists that may be added to the oral contraceptive pill, but they are not approved by the FDA for this indication; flutamide is not usually recommended because of its unproven efficacy and associated risk of hepatic impairment
If fertility is desired
- Preferred regimen (1): Clomiphene, alone or in combination with glucocorticoids, is the first-choice treatment
- Preferred regimen (2): Follicle-stimulating hormone may be administered in conjunction with timed human chorionic gonadotropin for ovulation induction
- Preferred regimen (3): Metformin
Primary Prevention
There is no established method for prevention of PCOS
Secondary Prevention
Secondary preventive measures for PCOS include
- Weight loss and metformin may prevent diabetes and atherosclerosis.
- Lifestyle modification, including increased physical activity and healthy diet resulting in weight loss, is also likely to prevent diabetes in PCOS.
Disease | Headache | Symptoms | Diagnosis | |
---|---|---|---|---|
CT/MRI | Other Investigation Findings | |||
Subarachnoid hemorrhage |
|
|
LP will show:
| |
Meningitis |
|
|
| |
Intracranial mass |
|
|
||
Cerebral hemorrhage |
|
|
| |
Cerebral Infarction |
|
|
| |
Intracranial venous thrombosis |
|
|
| |
Migraine |
|
|||
Head injury |
|
|
| |
Lymphocytic hypophysitis |
Seen in late pregnancy or the postpartum period with the following symptoms:
|
|||
Radiation injury |
|
|
PET scan
|
Medical Therapy
Pharmacotherapy
Medical treatment of PCOS is tailored to the patient's goals. Broadly, these may be considered under three categories:
- Restoration of fertility
- Treatment of hirsutism or acne
- Restoration of regular menstruation, and prevention of endometrial hyperplasia and endometrial cancer
In each of these areas, there is considerable debate as to the optimal treatment. One of the major reasons for this is the lack of large scale clinical trials comparing different treatments. Smaller trials tend to be less reliable, and hence may produce conflicting results.
General interventions that help to reduce weight or insulin resistance can be beneficial for all these aims, because they address what is believed to be the underlying cause of the syndrome. Where PCOS is associated with overweight or obesity, successful weight loss is probably the most effective method of restoring normal ovulation/menstruation, but many women find it very difficult to achieve and sustain significant weight loss. Low-carbohydrate diets and sustained regular exercise may help, and some experts recommend a low-GI diet in which a significant part of the total carbohydrates are obtained from fruit, vegetables and wholegrain sources.
Many women find insulin-lowering medications such as metformin hydrochloride (Glucophage®), pioglitazone hydrochloride (Actos®), and rosiglitazone maleate (Avandia®) helpful, and ovulation may resume when they use these agents. Many women report that metformin use is associated with upset stomach, diarrhea, and weight-loss. Such side effects usually resolve within 2–3 weeks. Starting with a lower dosage and gradually increasing the dosage over 2–3 weeks and taking the medication toward the end of a meal may reduce side effects. It may take up to six months to see results, but when combined with exercise and a low glycemic index diet up to 85% will improve menstrual cycle regularity and ovulation.
Treatment of Infertility
- Clomiphene citrate and metformin are the principal treatments used to help infertility. [3]
- In a random trial, 626 women were randomized to three groups: metformin alone, clomiphene alone, or both. The live birth rates after 6 months were 7.2% (metformin), 22.5% (clomiphene), and 26.8% (both).
- The major complication of clomiphene was multiple pregnancies, affecting 0%, 6% and 3.1% of women respectively.
- However, many specialists continue to recommend metformin which has, separately, been shown to increase ovulation rates [4] and reduce miscarriage rates.[5]. Metformin may be a rational choice in women in whom significant insulin resistance is diagnosed or suspected, as clomiphene works through a different mechanism and does not affect insulin resistance.
Diet adjustments and weight loss also increase rates of pregnancy. The most drastic increase in ovulation rate occurs with a combination of diet modification, weight loss, and treatment with metformin and clomiphene citrate[6]. It is currently unknown if diet change and weight loss alone have an effect on live birth rates comparable to those reported with clomiphene and metformin.
Though the use of basal body temperature or BBT charts is sometimes advised to predict ovulation, clinical trials have not supported a useful role.
For patients who do not respond to clomiphene, metformin, other insulin-sensitizing agents, diet and lifestyle modification, there are options available including assisted reproductive technology procedures such as controlled ovarian hyperstimulation and in vitro fertilisation. Ovarian stimulation has an associated risk of ovarian hyperstimulation in women with PCOS — a dangerous condition with morbidity and rare mortality. Thus recent developments have allowed the oocytes present in the multiple follicles to extracted in natural, unstimulated cycles and then matured in vitro, prior to IVF. This technique is known as IVM (in-vitro-maturation)
Though surgery is usually the treatment option of last resort, the polycystic ovaries can be treated with surgical procedures such as
- laparoscopy electrocauterization or laser cauterization
- ovarian wedge resection (rarely done now because it is more invasive and has a 30% risk of adhesions, sometimes very severe, which can impair fertility) was an older therapy
- ovarian drilling
Treatment of Hirsutism and Acne
Cyproterone acetate is an anti-androgen, which blocks the action of male hormones that are believed to contribute to acne and the growth of unwanted facial and body hair. Cyproterone acetate is also contained in the contraceptive pill Dianette®. Spironolactone also has some benefits, again through anti-androgen activity, and metformin can also help. Eflornithine is a drug which is applied to the skin in cream form (Vaniqa®), and acts directly on the hair follicles to inhibit hair growth. It is usually applied to the face.
Although all of these agents have shown some efficacy in clinical trials, the average reduction in hair growth is generally in the region of 25%, which may not be enough to eliminate the social embarrassment of hirsutism, or the inconvenience of plucking/shaving. Individuals may vary in their response to different therapies, and it is usually worth trying other drug treatments if one does not work, but drug treatments do not work well for all individuals. Alternatives include electrolysis and various forms of laser therapy.
Treatment of Menstrual Irregularity and Prevention of Endometrial Hyperplasia/Cancer
- If fertility is not the primary aim, then menstruation can usually be regulated with a contraceptive pill.
- Most brands of contraceptive pill result in a withdrawal bleed every 28 days.
- Dianette® (a contraceptive pill containing cyproterone acetate) is also beneficial for hirsutism and is therefore often prescribed in PCOS.
- If a regular menstrual cycle is not desired, then a standard contraceptive pill is not appropriate.
- Women who are having irregular menses do not necessarily require any therapy; most experts consider that if a menstrual bleed occurs at least every three months, then the endometrium (womb lining) is being shed sufficiently often to prevent an increased risk of endometrial abnormalities or cancer.
- If menstruation occurs less often or not at all, some form of progestogen replacement is recommended. Some women prefer a uterine progestogen implant such as the Mirena® coil, which provides simultaneous contraception and endometrial protection for years, though often with unpredictable minor bleeding.
- An alternative is oral progestogen taken at intervals (e.g. every three months) to induce a predictable menstrual bleed.
Approach to hyperandrogenism
Signs of hyperandrogenism hirsutism, alopecia, masculine appearance, acne | |||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
History of Drug use | Presence of oligomenorrhea | ||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
Stop using the drug PCOS ruled out | |||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
Perform an ultrsound of pelvis | |||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
Normal morphology of ovaries | Cystic morphology of ovaries | ||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
PCOS is ruled out Look for adrenal tumors, ovarian tumors | Measure testosterone levels | ||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
*17-hydroxyprogesterone/DHEAs elevated = CAH,adrenal tumors *Cortisol elevated = Cushings syndrome, cortisol resistance Prolactin,TSH,IGF1 abnormal = hyperprolactinoma, thyroid dysfunction acromegaly | |||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
Normal | Elevated | ||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
Risk factors of hirutism present? | PCOS | ||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
No | Yes | ||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
PCOS ruled out | Hirutism present? | ||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
Mild hirutism | Severe Hirutism | ||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
PCOS | |||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
Trial of OCP | |||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
Positive response | Negative worsening of symptoms | ||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
Idiopathic hirutism | PCOS | ||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
Schistosomiasis
Historical Perspective
- In 1847, Japanese Doctor Y. Fujii described “Katayama fever” as a manifestation of acute schistosomiasis.
- 1851, Dr.Theodore Billharz, working in Egypt, identified the worms responsible for Schistosomiasis.
- 1904, S. japonicum was identified in a housecat.
- 1915, the snail was identified as an intermediate host for Schistosomiasis.
Classification
Organ involved | Species | Geographical distribution | |
---|---|---|---|
Intestinal schistosomiasis |
|
||
Urogenital schistosomiasis | |||
Pathophysiology
- Schistosomes have a typical trematode vertebrate-invertebrate lifecycle, with humans being the definitive host.
- The life cycles of all five human schistosomes are broadly similar
- Parasite eggs are released into the environment from infected individuals, hatching on contact with fresh water to release the free-swimming miracidium.
- Miracidia infect fresh-water snails by penetrating the snail's foot.
- After infection, close to the site of penetration, the miracidium transforms into a primary (mother) sporocyst.
- Germ cells within the primary sporocyst will then begin dividing to produce secondary (daughter) sporocysts, which migrate to the snail's hepatopancreas.
- Once at the hepatopancreas, germ cells within the secondary sporocyst begin to divide again, this time producing thousands of new parasites, known as cercariae, which are the larvae capable of infecting mammals.
- Cercariae emerge daily from the snail host in a circadian rhythm, dependent on ambient temperature and light.
- Young cercariae are highly motile, alternating between vigorous upward movement and sinking to maintain their position in the water.
- Cercarial activity is particularly stimulated by water turbulence, by shadows and by chemicals found on human skin.
- Penetration of the human skin occurs after the cercaria have attached to and explored the skin.
- The parasite secretes enzymes that break down the skin's protein to enable penetration of the cercarial head through the skin.
- As the cercaria penetrates the skin it transforms into a migrating schistosomulum stage.
- The newly transformed schistosomulum may remain in the skin for 2 days before locating a post-capillary venule from here the schistosomulum travels to the lungs where it undergoes further developmental changes necessary for subsequent migration to the liver.
- Eight to ten days after penetration of the skin, the parasite migrates to the liver sinusoids.
- S. japonicum migrates more quickly than S. mansoni, and usually reaches the liver within 8 days of penetration.
- Juvenile S. mansoni and S. japonicum worms develop an oral sucker after arriving at the liver, and it is during this period that the parasite begins to feed on red blood cells.
- The nearly-mature worms pair, with the longer female worm residing in the gynaecophoric channel of the male.
- Adult worms are about 10 mm long. Worm pairs of S. mansoni and S. japonicum relocate to the mesenteric or rectal veins.
- S. haematobium schistosomula ultimately migrate from the liver to the perivesical venous plexus of the bladder, ureters, and kidneys through the hemorrhoidal plexus.
- Parasites reach maturity in six to eight weeks, at which time they begin to produce eggs.
- Adult S. mansoni pairs residing in the mesenteric vessels may produce up to 300 eggs per day during their reproductive lives.
- S. japonicum may produce up to 3000 eggs per day. Many of the eggs pass through the walls of the blood vessels, and through the intestinal wall, to be passed out of the body in faeces.
- S. haematobium eggs pass through the ureteral or bladder wall and into the urine. Only mature eggs are capable of crossing into the digestive tract, possibly through the release of proteolytic enzymes, but also as a function of host immune response, which fosters local tissue ulceration.
- Up to half the eggs released by the worm pairs become trapped in the mesenteric veins, or will be washed back into the liver, where they will become lodged.
- Worm pairs can live in the body for an average of four and a half years but may persist up to 20 years.
- Trapped eggs mature normally, secreting antigens that elicit a vigorous immune response.
- The eggs themselves do not damage the body. Rather it is the cellular infiltration resultant from the immune response that causes the pathology classically associated with schistosomiasis.
References
- ↑ Sortino MA, Salomone S, Carruba MO, Drago F (2017). "Polycystic Ovary Syndrome: Insights into the Therapeutic Approach with Inositols". Front Pharmacol. 8: 341. doi:10.3389/fphar.2017.00341. PMC 5463048. PMID 28642705.
- ↑ "Revised 2003 consensus on diagnostic criteria and long-term health risks related to polycystic ovary syndrome". Fertil. Steril. 81 (1): 19–25. 2004. PMID 14711538.
- ↑ Legro RS, Barnhart HX, Schlaff WD (2007). "Clomiphene, Metformin, or Both for Infertility in the Polycystic Ovary Syndrome". N Engl J Med. 356 (6): 551–566. PMID 17287476.
- ↑ "Efficacy of metformin for ovulation induction in polycystic ovary syndrome". Endocrine Abstracts.
- ↑ "Diabetes Drug Helps Prevent Miscarriage". WebMD.
- ↑ "Do insulin-sensitizing drugs increase ovulation rates for women with PCOS?". Find Articles.