ByAla'a Fadhel Hassan5th stage, pharmacy

departmentHospital training

Supervised byDr.Salaam

Definition Hydatidiform mole is a relatively rare condition in which tissue around a fertilized egg that normally would have developed into the placenta instead develops as an abnormal cluster of cells. (This is also called a molar pregnancy.) This grapelike mass forms inside of the uterus after fertilization instead of a normal embryo. A hydatidiform mole triggers a positive pregnancy test and in some cases can become cancerous. (1)It is a type of gestational trophoblastic disease (GTD), the term is derived from hydatidiform ("like a bunch of grapes") and mole (from Latin mola = millstone) (2) (or hydatid mole, mola hydatidosa). (3)

DescriptionA hydatidiform mole ("hydatid" means "drop of water" and "mole" means "spot") occurs in about 1 out of every 1,500 ( pregnancies in the United States. In some parts of Asia, however, the incidence may be as high as 1 in 200 (1) Hydatidiform mole is listed as a "rare disease" by the Office of Rare Diseases (ORD) of the National Institutes of Health (NIH). This means that hydatidiform mole, or a subtype of hydatidiform mole, affects less than 200,000 people in the US population (4). Molar pregnancies are most likely to occur in younger and older women (especially over age 45) than in those between ages 20-40. About 1-2% of

the time a woman who has had a molar pregnancy will have a second one.A molar pregnancy occurs when cells of the chorionic villi (tiny projections that attach the placenta to the lining of the uterus) don't develop correctly. Instead, they turn into watery clusters that can't support a growing baby. A partial molar pregnancy includes an abnormal embryo (a fertilized egg that has begun to grow) that does not survive. In a complete molar pregnancy there is a small cluster of clear blisters or pouches that don't contain an embryo.If not removed, about 15% of moles can become cancerous. They burrow into the wall of the uterus and cause serious bleeding. Another 5% will develop into fast-growing cancers called choriocarcinoma. Some of these tumors spread very quickly outside the uterus in other parts of the body. Fortunately, cancer developing from these moles is rare and highly curable (4)

EtiologyThe etiology of this condition is not completely understood. Potential risk factors may include defects in the egg, abnormalities within the uterus, or nutritional deficiencies. Women under 20 or over 40 years of age have a higher risk. Other risk factors include diets low in protein, folic acid, and carotene. The diploid set of sperm-only DNA means that all chromosomes have sperm-patterned methylation suppression of genes. This leads to overgrowth of the syncytiotrophoblast whereas dual egg-patterned methylation leads to a devotion of resources to the embryo, with an underdeveloped syncytiotrophoblast. This is considered to be the result of evolutionary competition with male genes driving for high

investment into the fetus versus female genes driving for resource restriction to maximize the number of children (2)

PathophysiologyA mole is characterized by a conceptus  of hyperplastic trophoblastic tissue attached to the placenta. The conceptus does not contain the inner cell mass (the mass of cells inside the primordial embryo that will eventually give rise to the fetus).The hydatidiform mole can be of two types: a complete mole, in which the abnormal embryonic tissue is derived from the father only; and a partial mole, in which the abnormal tissue is derived from both parents. (2)

Complete moles usually occur when an empty ovum is fertilized by a sperm that then duplicates its own DNA (a process called androgenesis). This explains why most complete moles are of the 46, XX genotype. A 46, XY genotype may occur when 2 sperm (one 23, X and the other 23, Y) fertilize an empty egg. They grossly resemble a bunch of grapes ("cluster of grapes" or "honeycombed uterus" or "snow-storm"). Their DNA is purely paternal in origin (since all chromosomes are derived from the sperm), and is diploid (i.e. there are two copies of every chromosome). Ninety percent are 46, XX, and 10% are 46, XY. In a complete mole, the fetus fails to develop, thus on gross examination there are no signs of fetal tissue. All of the chorionic villi are enlarged. The main complication of the

complete mole is a 2% chance of progression to a cancer called choriocarcinoma .(2)

* U/S evaluationAllows identification of numerous, discrete, anechoic (cystic) spaces within a central area of heterogeneous echotexture (5)

*Diagnostic Findings/Ultrasonography

Complete hydatidiform mole has a classic sonographic appearance of a solid collection of echoes with numerous anechoic spaces (snowstorm appearance). (5)

Theca lutein cysts

multiloculated,

often bilateralresolve after treatment of the intrauterine processOccasionally seen in twin gestations, fetal hydrops, pharmacologic stimulation (especially with human maternal gonadotropin)

.

Snow storm ultrasound (hydatidiform mole)  *CT

A CT scan usually demonstrates a normal-sized uterus with areas of low attenuation, an enlarged inhomogeneous uterus with a central area of low

attenuation, or hypoattenuating foci surrounded by highly enhanced areas in the myometrium.(5)

Complete mole images (2)

Another image of complete mole (2)

Partial moles can occur if a normal haploid  ovum is fertilized by two sperm, or if fertilized by one sperm, if the paternal chromosomes become duplicated. Thus their DNA is both maternal and paternal in origin. They can be triploid (e.g. 69 XXX, 69 XXY) or even tetraploid. Fetal parts are often seen on gross examination. There is also an increased risk of choriocarcinoma, but the risk is lower than with the complete mole.

*U/S evaluation, ultrasound has limited value in detecting partial molar pregnancies. (5)

In partial moles, the placenta is enlarged and contains areas of multiple, diffuse anechoic lesions

The finding of multiple cystic spaces in the placenta is suggestive of a partial molar pregnancy.

When there is diagnostic doubt about the possibility of a combined molar pregnancy with a viable fetus then ultrasound examination should be repeated before intervention.

The clues for the sonographer in this diagnosis are the presence of a fetus (although usually with severe, but nonspecific, abnormalities) in

combination with a formed placenta containing numerous cystic spaces

In twin pregnancies with a viable fetus and a molar pregnancy, the pregnancy can be allowed to proceed

*twin pregnancies with a viable fetus and a molar pregnancy are invasive mole A trophoblastic proliferation that penetrates the myometrium, and may undergo malignant degeneration into a choriocarcinoma (1) Simple comparison between complete & partial mole (5)

Partial MoleComplete MoleFeaturePresentAbsentEmbryonic or fetal

tissueFocalDiffuseSwelling of the villi FocalDiffuseTrophoblastic

hyperplasiaPaternal and maternal 69 XXY or 69 XYY

Paternal 46 XX (96%) or 46 XY (4%)

Karyotype

Rare5-10%Malignant Changes

Causes and symptoms The cause of hydatidiform mole is unclear; some experts believe it is caused by problems with the

chromosomes (the structures inside cells that contain genetic information) in either the egg or sperm, or both. It may be associated with poor nutrition, or a problem with the ovaries or the uterus. A mole sometimes can develop from placental tissue that is left behind in the uterus after a miscarriage or childbirth.Women with a hydatidiform mole will have a positive pregnancy test and often believe they have a normal pregnancy for the first three or four months. However, in these cases the uterus will grow abnormally fast. By the end of the third month, if not earlier, the woman will experience vaginal bleeding ranging from scant spotting to excessive bleeding. She may have hyperthyroidism (overproduction of thyroid hormones causing symptoms such as weight loss, increased appetite, and intolerance to heat). Sometimes, the grapelike cluster of cells itself will be shed with the blood during this time. Other symptoms may include severe nausea and vomiting and high blood pressure. As the pregnancy progresses, the fetus will not move and there will be no fetal heartbeat. (1)

Symptoms (6) (7) Abnormal growth of the womb (uterus)o Excessive growth in about half of caseso Smaller-than-expected growth in about a third of

cases Nausea and vomiting that may be severe enough

to require a hospital stay

Vaginal bleeding in pregnancy during the first 3 months of pregnancy

Symptoms of hyperthyroidismo Heat intoleranceo Loose stoolso Rapid heart rateo Restlessness, nervousnesso Skin warmer and more moist than usualo Trembling handso Unexplained weight loss Symptoms similar to preeclampsia that occur in

the 1st trimester or early 2nd trimester -- this is almost always a sign of a hydatidiform mole, because preeclampsia is extremely rare this early in a normal pregnancy

o High blood pressureo Swelling in feet, ankles, legs

Follow diagram of predisposing factors (8)

Exams and Tests A pelvic examination may show signs similar to a normal pregnancy, but the size of the womb may be abnormal and the baby's heart sounds are absent. There may be some vaginal bleeding.A pregnancy ultrasound will show an abnormal placenta with or without some development of a baby. (6)Tests may include: (7)

HCG blood test Chest x-ray CT or MRI of the abdomen Complete blood count Blood clotting tests Kidney and liver function tests

Diagnosis Molar pregnancies usually present with painless vaginal bleeding in the fourth to fifth month of pregnancy. The uterus may be larger than expected, or the ovaries may be enlarged. There may also be more vomiting than would be expected (hyperemesis). Sometimes there is an increase in blood pressure along with protein in the urine. Blood tests will show very high levels of human chorionic gonadotropin (hCG). (2)The diagnosis is strongly suggested by ultrasound (sonogram), but definitive diagnosis requires histopathological examination.Sometimes symptoms of hyperthyroidism are seen, due to the extremely high levels of hCG, which can

mimic the normal Thyroid-stimulating hormone (TSH). (3)

Misdiagnosis and Hydatidiform mole (9)*Unnecessary hysterectomies due to undiagnosed bleeding disorder in women: e.g. bleeding disorder called Von Willebrand's disease is quite common.

*Chronic digestive conditions often misdiagnosed: When diagnosing chronic symptoms of the digestive tract, there are a variety of conditions that may be misdiagnosed; the best known e.g. irritable bowel dis.

*Intestinal bacteria disorder may be hidden cause: One of the lesser known causes of diarrheais an imbalance of bacterial in the gut, sometimes called intestinal imbalance.

*Antibiotics often causes diarrhea: The use of antibiotics are very likely to cause some level of diarrhea in patients.

*Food poisoning may actually be an infectious disease: Many people who come down with "stomach symptoms".

*Mesenteric adenitis misdiagnosed as appendicitis in children: Because appendicitis is one of the more feared conditions for a child with abdominal pain, it can be over-diagnosed.

*Rare type of breast cancer without a lump: There is a less common form of breast cancer called inflammatory breast cancer. Its symptoms can be an inflammation of the breast tissue

*Spitz nevi misdiagnosed as dangerous melanoma skin cancer: One possible misdiagnosis to consider in lieu of melanoma  is spitz nevi.

*Psoriasis often undiagnosed cause of skin symptoms in children: Children who suffer from the skin disorder called psoriasis can often go undiagnosed.

*Celiac disease often fails to be diagnosed cause of chronic digestive symptoms, undiagnosed celiac disease in pregnancy harms fetus

*Chronic digestive diseases hard to diagnose: There is an inherent difficulty in diagnosing the various types of chronic digestive diseases.

*Misdiagnosed weight-related causes of infertility: A woman's weight status can affect her level of fertility.

Treatment Hydatidiform moles should be treated by evacuating the uterus by uterine suction or by surgical curettage as soon as possible after diagnosis, in order to avoid the risks of

choriocarcinoma. Patients are followed up until their serum human chorionic gonadotropin  (hCG) level has fallen to an undetectable level. Invasive or metastatic moles (cancer) may require chemotherapy and often respond well to methotrexate. The response to treatment is nearly 100%. (2)Patients are advised not to conceive for one year after a molar pregnancy. The chances of having another molar pregnancy are approximately 1%.Management is more complicated when the mole occurs together with one or more normal fetuses.Carboprost medication may be used to contract the uterus. (3)

Prognosis More than 80% of hydatidiform moles are benign. The outcome after treatment is usually excellent. Close follow-up is essential. Highly effective means of contraception are recommended to avoid pregnancy for at least 6 to 12 months. In 10 to 15% of cases, hydatidiform moles may develop into invasive moles. This condition is named persistent trophoblastic disease (PTD). The moles may intrude so far into the uterine wall that hemorrhage or other complications develop. It is for this reason that a post-operative full abdominal and chest x-ray will often be requested. In 2 to 3% of cases, hydatidiform moles may develop into choriocarcinoma, which is a malignant, rapidly-growing, and metastatic (spreading) form of cancer. Despite these factors which normally indicate a poor prognosis, the rate of cure after treatment with chemotherapy is high.

Over 90% of women with malignant, non-spreading cancer are able to survive and retain their ability to conceive and bear children. In those with metastatic (spreading) cancer, remission remains at 75 to 85%, although their childbearing ability is usually lost. (3)Possible Complications Lung problems may occur after a D and C if the woman's uterus is bigger than 16 weeks gestational size. (6)Other complications related to the surgery to remove a molar pregnancy include: (7)

Preeclampsia Thyroid problems

References(1) Definition of hydatidiform mole in the Medical dictionary - by the Free Online Medical Dictionary, Thesaurus and Encyclopedia.htmhttp://www.thefreedictionary.com/(2) http://www.wikidoc.org/index.php/File:Mole _Hyd.jpg(3) http://wikimediafoundation.org/ Hydatidiform mole - Wikipedia, the free encyclopedia.htm(4) Source - National Institutes of Health (NIH)

http://www.rightdiagnosis.com/

(5)Grade C recommendationDr. MOHAMMED ABDALLAEGYPT, DOMIAT G. HOSPITALVesicularMole-abdalla.pptx(6) http://www.nlm.nih.gov/medlineplus/medline plus.html

A service of the U.S. National Library of Medicine 

National Institutes of Health(7) http://health.nytimes.com/health/guides/ index .html

Friday, May 4, 2012 Thursday, May 3, 2012

Health Guide(8) http://nursingdepartment.blogspot.com/(9)Hydatidiform mole: Related Patient Stories