martes, 24 de julio de 2012

 embryology

 

Pregnancy 

Pregnancy is the fertilization and development of one or more offspring, known as an embryo or fetus, in a woman's uterus. In a pregnancy, there can be multiple gestations, as in the case of twins or triplets. Childbirth usually occurs about 38 weeks after conception; in women who have a menstrual cycle length of four weeks, this is approximately 40 weeks from the start of the last normal menstrual period (LNMP). Human pregnancy is the most studied of all mammalian pregnancies. Conception can be achieved through sexual intercourse or assisted reproductive technology.

An embryo is the developing offspring during the first 8 weeks following conception, and subsequently the term fetus is used henceforth until birth.  40% of pregnancies in the United States and United Kingdom are unplanned, and between a quarter and half of those unplanned pregnancies were unwanted pregnancies.

In many societies’ medical or legal definitions, human pregnancy is somewhat arbitrarily divided into three trimester periods, as a means to simplify reference to the different stages of prenatal development. The first trimester carries the highest risk of miscarriage (natural death of embryo or fetus). During the second trimester, the development of the fetus can be more easily monitored and diagnosed. The beginning of the third trimester often approximates the point of viability, or the ability of the fetus to survive, with or without medical help, outside of the uterus.


First Trimester

Weeks 0 to 12
At the beginning of your first trimester, the first month of pregnancy, a water-tight sac, known as the amniotic sac, begins to develop around the fertilized egg in your uterus. The placenta then begins to develop to help provide nutrients to your growing embryo. The placenta is also instrumental in removing wasted from your baby.
First TrimesterEven in the first month your baby will begin to develop a tiny little face, with dark black circles for eyes. Cells begin to take shape developing body parts such as the mouth, throat and lower jaw. Circulatory systems become active, powering massive cell growth. At the end of the first month your baby will still be tiny, only about the size of a piece of rice or about a quarter inch.
During the second month your baby’s facial features will continue to develop. Small folds on the sides of the head will soon become tiny little ears. Small bulbs will begin to develop on the side of the embryo which will become future arms and legs. Fingers and toes will also begin to develop at the ends of those arms and legs.
The neural tube will begin to develop which eventually becomes your baby’s brain and spinal cord. The digestive system and other sense organs also begin development. Cartilage starts to become bone and your little embryo may even start moving, although it’s impossible to feel at this point. By the end of the second month your embryo will have grown to about 1 inch long, with 1/3 of that being the head alone.
In the last month of the first trimester, your baby will already be fully formed complete with tiny arms, legs, hands, feet, fingers and toes. Your baby will even be able to open and close its hands and mouth by this point. External ears will begin to spring out and things like fingernails, toenails and teeth are all well on their way. Although sexual organs will have developed by the end of the first trimester, it’ll be almost impossible to detect on an ultrasound.

Second Trimester

Weeks 13 to 28
By the first week of your second trimester your baby’s features have become well defined. Things like eyelids, eyelashes and hair begin to form. Bones become stronger during the second trimester including teeth. Your baby will be able to do things like suck their thumb, stretch or even yawn.
Second TrimesterThe nervous system becomes fully active during the second trimester. The reproductive organs and genitals have become full formed, allowing you to determine the sex of your baby for the first time using an ultrasound. Your baby’s heart will be pumping strong and can even be listened to using a device known as a fetal Doppler. By the end of your fourth month of pregnancy your baby will have grown to be about 6 inches long and will weigh about a quarter pound.
By the fifth month of pregnancy, in the middle of your second trimester, your baby will develop soft peach fuzz hair that usually covers the back and shoulders and can even cover parts of the face. This can make your little one look a little like Sasquatch when they first come out, but don’t worry. This hair is typically shed in the first week or two of your baby’s life. Your baby’s skin will also become covered in a white coating known as vernix caseosa that’s thought to protect your baby from the amniotic fluid in the womb. Fortunately, this cheesy substance is shed before birth. By the end of the fifth month your baby will be about 10 inches long and could weigh up to a pound.
By the end of the second trimester, in the sixth month, your baby will be about 12 inches long and could weigh up to 2 pounds. Their skin will be kind of wrinkled and reddish with visible veins appearing through a translucent layer of skin. Fingers and toes are visible and you can even start to see little fingerprints. The best part about the end of the second trimester is that you will finally be able to feel your baby move. Your may even feel a slight jerking sensation that’s caused by baby hiccups.

Third Trimester

Weeks 29 to 40
Your third trimester begins during your seventh month of pregnancy. During this month fat begins to form in your baby’s body. Your baby may be up to 14 inches or longer at this point and could weight anywhere from 2 to 5 pounds. At this stage your baby’s hearing is fully developed, so it’s important to be sensitive to this fact. Your baby will begin to respond to things such as sound, pain and even light at this stage of pregnancy.
Third TrimesterThe eighth month of pregnancy is very similar to the seventh. Your baby will continue to build fat reserves which will allow them to function free of mommy’s womb. Your baby will be up to 18 inches or longer at this point and will weigh up to five pounds. Multiples will weigh slightly less at this point but will be at the same point of development as other babies. While most internal systems have been fully developed by this point, the lungs may still not be fully mature.
The end of the third trimester marks your final month of pregnancy. During this month your baby will continue to grow and develop, although there should be significantly less weight gain this month. At this stage your baby will be able to blink, turn their head and grasp using a tiny fist. This month you may notice an increased sensitivity in your baby to outside stimulation like light, sound and touch.
At the end of the third trimester your baby will begin to position herself to prepare to delivery. Your baby will drop down into your pelvis with her head facing towards the birth canal. If her head isn’t facing the birth canal, a Caesarian section (c section) may be necessary. By the end of the third trimester your baby will be 15 to 20 inches long and could weight from 6 to 8 pounds or more.

Ectopic pregnancy


An ectopic pregnancy is a complication of pregnancy in which the embryo implants outside the uterine cavity. With rare exceptions, ectopic pregnancies are not viable. Most ectopic pregnancies occur in the Fallopian tube (so-called tubal pregnancies), but implantation can also occur in the cervix, ovaries, and abdomen. It should be considered in any woman with abdominal pain or vaginal bleeding who has a positive pregnancy test. An ultrasound showing a gestational sac with fetal heart in a location other than the uterine cavity is clear evidence of an ectopic pregnancy. Tubal ectopic pregnancy is the most common cause of maternal death in the first trimester of pregnancy.

About 1% of pregnancies are in an ectopic location with implantation not occurring inside of the womb, and of these 98% occur in the Fallopian tubes. In a typical ectopic pregnancy, the embryo adheres to the lining of the fallopian tube and burrows into the tubal lining. Most commonly this invades blood vessels which causes bleeding resulting in the expulsion of the implantation from the tube. Termed "tubal abortions", about half of ectopic pregnancies will resolve without treatment. The use of methotrexate treatment for ectopic pregnancy has reduced the need for surgery, but surgical intervention is still required in cases where the Fallopian tube has ruptured or is in danger of doing so. The surgical intervention may be laparoscopic or through a larger incision, known as a laparotomy.

A woman who has had a previous ectopic pregnancy is more likely to have another. The majority of women with ectopic pregnancies have had pelvic inflammatory disease or salpingitis, an inflammation of the fallopian tube. A history of gonorrhea or chlamydia can also cause tubal problems that increase the risk. Endometriosis, a condition that causes the tissue that normally lines the uterus to develop outside the uterus may slightly increase the incidence of an ectopic. The risk is increased in women who have unusually shaped fallopian tubes or tubes which has been damaged, possibly during surgery. Taking medication to stimulate ovulation increases the risk of ectopic pregnancy. Although pregnancy is rare when using birth control pills or an intrauterine device (IUD), if it does occur, it's more likely to be ectopic. Although pregnancy is rare after tubal ligation, if it does occur, it's more likely to be ectopic. A recent meta-analysis of clinical outcomes has shown that cigarette smoking significantly increases the risk of tubal ectopic pregnancy.


Congenital disorder

 A congenital disorder, or congenital disease, is a condition existing at birth and often before birth, or that develops during the first month of life (neonatal disease), regardless of causation. Of these diseases, those characterized by structural deformities are termed "congenital anomalies"; that is a different concept (MeSH) which involves defects in or damage to a developing fetus.

A congenital disorder may be the result of genetic abnormalities, the intrauterine (uterus) environment, errors of morphogenesis, infection, or a chromosomal abnormality. The outcome of the disorder will depend on complex interactions between the pre-natal deficit and the post-natal environment. Animal studies indicate that the mother's (and possibly the father's) diet, vitamin intake, and glucose levels prior to ovulation and conception have long-term effects on fetal growth and adolescent and adult disease. Congenital disorders vary widely in causation and abnormalities. Any substance that causes birth defects is known as a teratogen.

The older term congenital  disorder does not necessarily refer to a genetic disorder despite the similarity of the words. Some disorders can be detected before birth through prenatal diagnosis (screening).
Classification

Much of the language used for describing congenital conditions predates genomic mapping, and structural conditions are often considered separately from other congenital conditions. It is now known that many metabolic conditions may have subtle structural expression, and structural conditions often have genetic links. Still, congenital conditions are often classified in a structural basis, organized when possible by primary organ system affected.

Several terms are used to describe congenital abnormalities. (Some of these are also used to describe noncongenital conditions, and more than one term may apply in an individual condition.)

    A congenital physical anomaly is an abnormality of the structure of a body part. An anomaly may or may not be perceived as a problem condition. Many, if not most, people have one or more minor physical anomalies if examined carefully. Examples of minor anomalies can include curvature of the 5th finger (clinodactyly), a third nipple, tiny indentations of the skin near the ears (preauricular pits), shortness of the 4th metacarpal or metatarsal bones, or dimples over the lower spine (sacral dimples). Some minor anomalies may be clues to more significant internal abnormalities.
    Birth defect is a widely used term for a congenital malformation, i.e. a congenital, physical anomaly which is recognizable at birth, and which is significant enough to be considered a problem. According to the CDC, most birth defects are believed to be caused by a complex mix of factors including genetics, environment, and behaviors, though many birth defects have no known cause. An example of a birth defect is cleft palate.
    A congenital malformation is a congenital physical anomaly that is deleterious, i.e. a structural defect perceived as a problem. A typical combination of malformations affecting more than one body part is referred to as a malformation syndrome.
    Some conditions are due to abnormal tissue development:
        A malformation is associated with a disorder of tissue development. Malformations often occur in the first trimester.
        A dysplasia is a disorder at the organ level that is due to problems with tissue development.
    It is also possible for conditions to arise after tissue is formed:
        A deformation is a condition arising from mechanical stress to normal tissue. Deformations often occur in the second or third semester, and can be due to oligohydramnios.
    A disruption involves breakdown of normal tissues.
    When multiple effects occur in a specified order, it is known as a sequence. When the order is not known, it is a syndrome.

Other

    Genetic disorders or diseases are all congenital, though they may not be expressed or recognized until later in life. Genetic diseases may be divided into single-gene defects, multiple-gene disorders, or chromosomal defects. Single-gene defects may arise from abnormalities of both copies of an autosomal gene (a recessive disorder) or of only one of the two copies (a dominant disorder). Some conditions result from deletions or abnormalities of a few genes located contiguously on a chromosome. Chromosomal disorders involve the loss or duplication of larger portions of a chromosome (or an entire chromosome) containing hundreds of genes. Large chromosomal abnormalities always produce effects on many different body parts and organ systems.
    A congenital metabolic disease is also referred to as an inborn error of metabolism. Most of these are single gene defects, usually heritable. Many affect the structure of body parts but some simply affect the function.

Female Reproductive System

 Physical Exam

I. History: sexually transmitted disease, menstrual history, obstetrical history, contraception

II. Inspection
  • External genitalia: Normal findings

    1. hair distribution: variable; usually inverted triangle starting at symphysis pubis
    2. skin of perineum smooth, clean, slightly darker than other skin
    3. labia majora - may be closed or gaping
    4. clitoris - about 2 cm in length and 0.5 cm in width
    5. urethral orifice - intact, pink without irritation
    6. vaginal orifice - ranges from thin, vertical slit to larger orifice with moist tissue
    7. anus - moist and hairless - skin more darkly pigmented

  • Internal genitalia:

    1. Cervix - normal findings: pink; midline; usually about 2 to 3 cm in diameter; smooth, firm, rounded or oval; odorless, creamy or clear secretions
    2. papanicolau (Pap) smear
    3. vagina - pink throughout; clear or cloudy, odorless secretions; about 10 to 15 cm in length
III. Palpation
  • Ovaries may or may not be palpable; firm, slightly tender, oval, mobile; about 4 cm in diameter
  • Uterus - mobile; rounded; palpable at level of pelvis
  • Skene's glands and Bartholin's gland - normal findings: nontender, no discharge

IV. Geriatric Alterations
  • Labial folds flatten
  • Skin paler, shiny
  • Meatus usually more posterior
  • Cervix decreases in size; may appear paler
  • Scanty cervical discharge
  • Vagina shortens with age
  • Decreased vaginal secretions
  • Uterus diminishes in size; may not be palpable
  • Ovaries atrophy with age
 

 dysmenorrhea

Are the periods in which a woman experiences pain in the lower abdominal cramping, severe pain and intermittent or possibly back pain.

Although some pain during menstruation is normal, excessive pain is not. The medical term for excessively painful periods is dysmenorrhea.
Considerations

Many women have painful periods. Sometimes the pain makes the performance of academic, normal household, job for a few days during each menstrual cycle. Painful menstruation is the leading cause for women from their teenage years and 20 years old to waste time at school and work.
Causes

Painful periods are classified into two groups, depending on the cause:

    Primary Dysmenorrhea
    Secondary dysmenorrhea

Primary dysmenorrhea refers to menstrual pain that occurs more or less around the time when menstrual periods are just beginning in otherwise healthy women. This type of pain usually is not related to specific problems in the uterus or other pelvic organs. It is thought that the increase in prostaglandin hormone activity, which occurs in the uterus, plays a role in this condition.

Secondary dysmenorrhea is menstrual pain that develops later in women who have had normal periods and often is related to problems with the uterus or other pelvic organs, such as:

    Endometriosis
    Fibroids
    Intrauterine device (IUD) made of copper
    Pelvic inflammatory disease
    Premenstrual syndrome (PMS)
    STI
    Stress and anxiety

Home Care

The following steps may allow you to avoid using drugs that require a prescription:

    
Apply a heating pad on the lower abdomen below the navel, but never fall asleep with a heating pad on.
    
Do light circular massage with the fingertips around your lower abdomen.
    
Drink hot liquids.
    
Eat little but often.
    
Eating a diet rich in complex carbohydrates such as whole grains, fruits and vegetables but low in salt, sugar, alcohol and caffeine.
    
Keep your legs elevated while lying down or lying on your side with knees bent.
    
Practicing relaxation techniques like meditation or yoga.
    
Try over-the-counter anti-inflammatory drugs like ibuprofen. Start taking it the day before when he is expected to start the period and continue taking it regularly during the first days of that period.
    
Try supplements of vitamin B6, calcium and magnesium, especially if the pain is from PMS.
    
Take warm showers or baths.
    
Walk or exercise regularly, including pelvic rocking exercises.
    
Lose weight if overweight. Regular aerobic exercise.
If these self care measures do not work, your doctor may prescribe medications such as:

    
Antibiotics
    
Antidepressants
    
Birth Control Pills
    
Prescription anti-inflammatory
    
Prescription analgesics (including narcotics for short periods)
When to Contact a Medical Professional
Call your doctor immediately if you have:

    
Vaginal discharge is increased or odor.
    
Fever and pelvic pain.
    
Sudden or severe pain, especially if your period is late by more than a week and has been sexually active.
 
 

Amenorrhea 

occurs when a woman has her monthly menstrual cycle or period.

    
Absence of menstruation
    
Primary amenorrhea
Causes, incidence, and risk factors
It is considered that women who are pregnant, breastfeeding or menopause have secondary amenorrhea.
Women who are taking birth control pills or receiving injections of hormones such as Depo-Provera may have no monthly bleeding. When they stop taking these hormones, your periods may not return for more than 6 months.
You are more likely to have amenorrhea if:

    
Are obese
    
Do you exercise excessively and for long periods of time
    
Has less than 15 to 17% body fat
    
Have severe anxiety or emotional distress
    
Excessive weight loss suddenly (for example, with a strict diet or gastric bypass surgery)
Other causes include:

    
Brain tumors (pituitary)
    
Polycystic ovary syndrome
    
Premature ovarian failure
    
Thyroid dysfunction
The following drugs may also cause missed periods:

    
Busulfan
    
Cancer chemotherapeutic drugs
    
Chlorambucil
    
Cyclophosphamide
    
Phenothiazines
Also, procedures such as dilation and curettage (D & C) can lead to the formation of scar tissue that can cause a woman to stop menstruating. This is called Asherman syndrome. Healing can also be caused by some severe pelvic infections.Symptoms

    
No menstrual period for six months or more
    
Previously had one or more periods that began spontaneously
Other symptoms that may occur with secondary amenorrhea include:

    
Changes in breast size
    
Weight gain or significant weight loss
    
Breast discharge (galactorrhea)
    
Headache
    
Increased hair growth in a "male" pattern (hirsutism) and acne
    
Vaginal dryness
    
Voice changes
If amenorrhea is caused by a pituitary tumor, there may be other symptoms related to the tumor, such as loss of vision.Signs and tests
They should do a pelvic exam and a physical examination to rule out pregnancy. Likewise, it is a pregnancy test.
They can do blood tests to check hormone levels, including:

    
Estradiol levels
    
Follicle stimulating hormone (FSH level)
    
Luteinizing hormone (LH level)
    
Prolactin level
    
Serum hormone levels such as testosterone levels
    
Thyroid stimulating hormone (TSH)
Other tests that may be done include:

    
CT scan of the head
    
Endometrial biopsy
    
Genetic Testing
    
MRI of the head
    
Pelvic ultrasound or sonohysterography
Treatment
Treatment depends on the cause of amenorrhea. Normal monthly periods usually return after treatment of the condition.
 
 
 

Endometriosis

Is a disorder in the health of women that occurs when cells in the lining of the uterus (womb) grows in other areas of the body. This can lead to this pain, irregular bleeding and problems getting pregnant (infertility).Causes
Each month, a woman's ovaries produce hormones that tell the cells lining the uterus (womb) become swollen and thicker. The body eliminates these extra cells of the uterine lining (endometrium) when you gets her period.
If these cells, called endometrial cells, implant and grow outside the uterus, endometriosis results. The tumors are called endometrial tissue implants. Women with endometriosis tissue implants typically have in the ovaries, bowel, rectum, bladder and the lining of the pelvic area. May also occur in other body areas.
Unlike endometrial cells found in the uterus, implants of tissue outside the uterus remain in place when it has the period. They sometimes bleed a little and grow back when you have the next period. This ongoing process leads to pain and other symptoms of endometriosis.
The cause of endometriosis is unknown. One theory is that endometrial cells that are shed during menstruation returned through the fallopian tubes into the pelvis, where they implant and multiply. This is called retrograde menstruation. This retrograde menstrual flow occurs in many women, but researchers think the immune system may be different in women with endometriosis.
Endometriosis is common and sometimes can be hereditary. Although endometriosis is typically diagnosed between 25 and 35, the condition probably begins about the time of onset of regular menstruation.
A woman who has a mother or sister with endometriosis are more likely to develop this disease than other women. You are more likely to have endometriosis if:

    
Menstruation began at an early age.
    
Never had children.
    
Has frequent menstrual periods or last 7 days or more.
    
Has a closed hymen, which blocks blood flow during the menstrual period.
Symptoms
Pain is the main symptom of endometriosis. A woman with this disease may have:

    
Painful periods.
    
Lower abdominal pain before and during menstruation.
    
Cramps a week or two before and during menstruation (cramps may be permanent and may be dull or quite severe).
    
Pain during or after intercourse.
    
Painful bowel movements.
    
Pelvic or back pain that can occur at any time during the menstrual cycle.
Note: You may not manifest any symptoms. Some women with a large number of tissue implants in the pelvis do not feel absolutely no pain, while some with mild disease have severe pain.Exams and Tests
The doctor will perform a physical examination including a pelvic exam. The tests done to help diagnose endometriosis include:

    
Pelvic exam
    
Transvaginal ultrasound
    
Pelvic laparoscopy
Treatment
Treatment depends on the following factors:

    
Age.
    
Severity of symptoms.
    
Severity of the disease.
    
If we want children in the future.
If you have mild symptoms and never want to have children, you can simply choose to have regular exams every 6 to 12 months so the doctor can see that the disease is getting worse. You can manage the symptoms by:

    
Exercise and relaxation techniques.
    
Nonsteroidal anti-inflammatory drugs (NSAIDs) such as ibuprofen (Advil), naproxen (Aleve), acetaminophen (Tylenol) or prescription pain medicines to relieve cramping and pain.
For other women, treatment options include:

    
Medications to control pain.
    
Hormonal medications to prevent the worsening of endometriosis.
    
Surgery to remove areas of endometriosis or the entire uterus and ovaries.
Treatment to stop the worsening of endometriosis often involves the use of birth control pills continuously for 6 to 9 months to prevent you from having your period and create a state similar to pregnancy, called pseudopregnancy. This therapy uses oral contraceptives containing estrogen and progesterone. This type of therapy relieves most of the symptoms of endometriosis, but does not prevent scarring neutralized nor any physical change that has already occurred as a result of disease
 
 
 

Male Reproductive System

 Physical Exam

 I. History: Sexual history, sexually transmitted disease, contraception, surgery, associated urinary problems
  • External genitalia
  • Hair distribution: varies; hair extends from base of penis over symphysis pubis; coarse and curly
  • Penis shaft, corona, prepuce, glans
  • Urethral meatus is slit like opening positioned on ventral surface, millimeters from tip of glans; opening should be glistening and pink
  • Scrotum:
    1. skin more darkly pigmented; more wrinkled; usually loose
    2. symmetry - left testicle is lower than right
    3. size - changes with temperature
  • Inguinal canal: no finding - no bulging
II. Palpation
  •  Penis:
    1. foreskin should retract easily
    2. small amount of thick white secretion between glans and foreskin is normal
    3. testicle - ovoid; ranges from 2-4 cm in diameter, smooth and rubbery; nontender
  • Inguinal canal: Normal finding - inguinal lymph nodes not palpable
III. Geriatric Alterations
  • Increased bogginess of prostrate
  • Testes softer
IV. Rectum and Anus
  • Inspection of perianal areas
    1. skin - smooth and uninterrupted
    2. anal tissues - normally moist and hairless
  • Digital palpation:
    1. Anal sphincter - note tone
    2. Rectal walls - smooth and even
    3. Prostrate gland = Palpate through anterior rectal wall; Small walnut-sized, heart shaped structure; Ranges from 2.5 to 4 cm in diameter; Normal findings - firm, protrudes <1 cm into rectum
  • Alterations:
    1. fissures
    2. fistulas
    3. polyps
    4. pain
    5. hemorrhoids



 Gynecomastia


 Gynecomastia is a benign enlargement of the male breast resulting from a proliferation of the glandular component of the breast (see the image below). Gynecomastia is defined clinically by the presence of a rubbery or firm mass extending concentrically from the nipples. Although the condition is usually bilateral, it can be unilateral. The condition known as pseudogynecomastia, or lipomastia, is characterized by fat deposition without glandular proliferation.

Reassure patients with physiologic gynecomastia regarding the benign nature of their condition, and inform them that most cases spontaneously resolve.
Counsel patients regarding the various treatment modalities available for gynecomastia, and highlight the risks, adverse effects, success rates, and benefits of each modality.



Prostate Diseases

The prostate is a gland. It helps make semen, the fluid that contains sperm. The prostate surrounds the tube that carries urine away from the bladder and out of the body. A young man's prostate is about the size of a walnut. It slowly grows larger with age. If it gets too large, it can cause problems. This is very common after age 50. The older men get, the more likely they are to have prostate trouble.

Some common problems are

    Prostatitis - an infection, usually caused by bacteria
    Benign prostatic hyperplasia, or BPH - an enlarged prostate, which may cause dribbling after urination or a need to go often, especially at night
    Prostate cancer - a common cancer that responds best to treatment when detected early




Nutrition and Metabolism



Nutrition (also called nourishment or aliment) is the provision, to cells and organisms, of the materials necessary (in the form of food) to support life. Many common health problems can be prevented or alleviated with a healthy diet.

The diet of an organism is what it eats, which is largely determined by the perceived palatability of foods. Dietitians are health professionals who specialize in human nutrition, meal planning, economics, and preparation. They are trained to provide safe, evidence-based dietary advice and management to individuals (in health and disease), as well as to institutions. Clinical nutritionists are health professionals who focus more specifically on the role of nutrition in chronic disease, including possible prevention or remediation by addressing nutritional deficiencies before resorting to drugs. While government regulation of the use of this professional title is less universal than for "dietician", the field is supported by many high-level academic programs, up to and including the Doctoral level, and has its own voluntary certification board

Anorexia

It is an eating disorder that leads people to lose more weight than is considered healthy for their age and height.

People with this disorder may have an intense fear of gaining weight, even when they are underweight. You may make dieting or exercising excessively or using other methods to lose weight.
causes

No one knows the exact causes of anorexia nervosa. Many factors probably are involved. Genes and hormones may play a role. Social attitudes that promote very slim body types may also contribute.

It is not believed that the conflicts within the family contribute to this or other eating disorders.

Risk factors predisposing to anorexia include:

     Be more concerned or pay more attention to weight and shape
     Having an anxiety disorder in childhood
     Having a negative self-image
     Have food problems during infancy or early childhood
     Have certain ideas about cultural and social health and beauty
     Trying to be a perfectionist or too focused on rules

Anorexia usually begins during the teenage years or early adulthood and is more common in women, but can also be seen in males. The disorder is seen mainly in Caucasian women, high achievement and who have family or personality oriented towards achieving goals.

Anorexia usually begins during the teenage years or early adulthood and is more common in women, but can also be seen in males. The disorder is seen mainly in Caucasian women, high achievement and who have family or personality oriented towards achieving goals.
symptoms

To be diagnosed with anorexia, a person must:

     Having an intense fear of gaining weight or becoming fat, even when they are underweight.
     Refusal to maintain weight in what is considered normal for their age and height (15% or more below normal weight).
     Having a body image that is very distorted, be very focused on body weight or shape, and refused to admit the gravity of the weight loss.
     Have not had your period for three or more cycles (in women).

People with anorexia may severely limit the amount of food they eat, or eat and then vomit. Other behaviors include:

     Cut food into small pieces or move them around the plate instead of eating them.
     Exercise at all times, even in bad weather, are injured or are too busy.
     Go to the bathroom immediately after meals.
     Refusing to eat around other people.
     Using pills that make urination (diuretics), have a bowel movement (enemas or laxatives) or decrease your appetite (diet pills)


Bulimia


It is an eating disorder that leads people to lose more weight than is considered healthy for their age and height.

People with this disorder may have an intense fear of gaining weight, even when they are underweight. You may make dieting or exercising excessively or using other methods to lose weight.
  causes

Many more women than men have bulimia, and the disorder is more common in adolescent girls and young women. The affected person is usually aware that her eating pattern is abnormal and may experience fear or guilt with episodes of binge and purge.

It is unknown the exact cause of bulimia, but genetic, psychological trauma, family, social or cultural factors may play a role. Bulimia is likely due to more than one factor.
symptoms

In bulimia, there may be episodes of overeating at a frequency of several times a day for many months.

People with bulimia typically eat large quantities of high calorie foods, usually in secret. The person often feels a lack of control over their eating during these episodes.

These episodes of excessive ingestion of foods cause a feeling of self-rejection, which leads to so-called purge to prevent weight gain. Purging may include:


     Induce vomiting.
     Excessive exercise.
     Use of laxatives, enemas or diuretics.

The purge often produces a feeling of relief.

People with bulimia are often normal weight, but they can see themselves overweight. Because the weight is often normal, others may not notice this eating disorder.

Digestive System Diseases

Digestion is the mechanical and chemical breakdown of food into smaller components that are more easily absorbed into a blood stream, for instance. Digestion is a form of catabolism: a breakdown of large food molecules to smaller ones. 

When food enters the mouth, its digestion starts by the action of mastication, a form of mechanical digestion, and the contact of saliva. Saliva, which is secreted by the salivary glands, contains salivary amylase, an enzyme which starts the digestion of starch in the food. After undergoing mastication and starch digestion, the food will now be in the form of a small, round mass, called a bolus. It will then travel down the esophagus and into the stomach by the action of peristalsis. Gastric juice in the stomach starts protein digestion. Gastric juice mainly contains hydrochloric acid and pepsin. As these two chemicals may damage the stomach wall, mucus is secreted by the stomach, providing a slimy layer that acts as a shield against the damaging effects of the chemicals. At the same time protein digestion is occurring, mechanical mixing occurs by peristalsis, which are waves of muscular contractions that move along the stomach wall. This allows the mass of food to further mix with the digestive enzymes. After some time (typically an hour or two in humans, 4–6 hours in dogs, somewhat shorter duration in house cats), the resulting thick liquid is called chyme. When the pyloric sphincter valve opens, chyme enters the duodenum where it mixes with digestive enzymes from the pancreas, and then passes through the small intestine in which digestion continues. When the chyme is fully digested, it is absorbed into the blood. 95% of absorption of nutrients occurs in the small intestine. Water and minerals are reabsorbed back into the blood in the colon (large intestine)

Gastritis


Gastritis is the inflammation of the lining of the stomach. This condition can be an acute (with rapid onset, short period, and usually severe intensity) or a chronic condition.
The two most common forms of gastritis:
  • Erosive gastritis
  • Non-erosive gastritis

Gastritis Symptoms

The symptoms of gastritis are:
  • Pain or burning sensation in the stomach, especially between meals or at night
  • Upset stomach
  • Blood in stool
In some people, gastritis does not have any symptoms.

How is Gastritis Diagnosed?

Your doctor may perform the following tests to diagnose this condition:
  • Upper endoscopy
    Here, an endoscope or a flexible tube with a camera is carefully threaded into the stomach to see the signs of gastritis.

    In erosive gastritis, there are visible tiny, superficial abrasions, erosions or holes in the stomach lining.

    In non-erosive gastritis, the stomach lining may be red or inflamed but there are no erosions. In some people, the lining may appear completely normal and a biopsy or tissue sample need to be taken, and further tests need to be performed.

  • Blood test
    For non-erosive gastritis, blood test may be done to see the presence of Heliobacter pylori (H. pylori) infection. Vitamin B12 level can also be tested, to confirm or rule out pernicious anemia as one of the cause.

Causes of Gastritis

The causes of gastritis include:
  • H. pylori infection

  • Non-steroidal anti-inflammatory drugs (NSAIDs)
    These are painkillers that can reduce the protective nature of the stomach lining against the digestive acids and enzymes in the stomach.

  • Drinking alcoholic beverages
    Alcohol stimulates the production of stomach acid and large doses of alcohol can damage and inflame the stomach.

  • Autoimmune disorder
    Here, the body’s immune system mistakenly attack the stomach lining. In this form of gastritis, the body is no longer able to absorb vitamin B12 thus resulting in a condition called pernicious anemia.

  • Immune response to other diseases
    Gastritis may also be caused by improper immune responses to other diseases such as Crohn’s disease and syphilis.

Treatment for Gastritis

Gastritis is treated with:
  • Antibiotics
    If H. pylori is present, antibiotics are prescribed to eliminate this bacteria.

  • Medications to reduce stomach acid
    These include:

    • Histamine or H2 blockers, which prevents the histamine receptors from stimulating the production of stomach acids

    • Proton pump inhibitors, which stop stomach acid production.
     


WATER AND ELECTROLYTE

 The water and electrolyte balance plays a central role in infusion therapy. First the
most important areas of the organism where water is located are explained followed
by the most important salts in the body. Furthermore, an explanation about the basic
regulation mechanisms is given. These mechanisms help to maintain the water and
electrolyte balance. The chapter closes with explanations about the water balance in
human beings including the process of fluid intake and loss.


SHIFTS IN GASTROINTESTINAL FLUID BALANCE
A special fluid balance exists between the blood plasma and the digestive tract secretions, which are formed of plasma as well. The total amount of fluids separated out in the intestinal tract may reach 8,200 ml in 24 hours. Fig. 8 explains the loss of fluid types and their constituent amount.
This large amount of fluid is reabsorbed through the mucosa of the large and small intestines into the bloodstream. This explains the fact that prolonged periods of vomiting or diarrhoea can lead to death within hours unless the lost fluid is replaced. This can be avoided by a massive infusion intake.

Electrolytes are important because they are what cells (especially nerve, heart, muscle) use to maintain voltages across their cell membranes and to carry electrical impulses (nerve impulses, muscle contractions) across themselves and to other cells. Kidneys work to keep the electrolyte concentrations in blood constant despite changes in your body. For example, during heavy exercise, electrolytes are lost in sweat, particularly sodium and potassium. These electrolytes must be replaced to keep the electrolyte concentrations of the body fluids constant.

Hypernatremia


 Hypernatremia or hypernatraemia is an electrolyte disturbance that is defined by an elevated sodium level in the blood. Hypernatremia is generally not caused by an excess of sodium, but rather by a relative deficit of free water in the body. For this reason, hypernatremia is often synonymous with the less precise term, dehydration.

Water is lost from the body in a variety of ways, including perspiration, insensible losses from breathing, and in the feces and urine. If the amount of water ingested consistently falls below the amount of water lost, the serum sodium level will begin to rise, leading to hypernatremia. Rarely, hypernatremia can result from massive salt ingestion, such as may occur from drinking seawater.

Ordinarily, even a small rise in the serum sodium concentration above the normal range results in a strong sensation of thirst, an increase in free water intake, and correction of the abnormality. Therefore, hypernatremia most often occurs in people such as infants, those with impaired mental status, or the elderly, who may have an intact thirst mechanism but are unable to ask for or obtain water.


Hyperkalemia

 refers to the condition in which the concentration of the electrolyte potassium (K+) in the blood is elevated. Extreme hyperkalemia is a medical emergency due to the risk of potentially fatal abnormal heart rhythms (arrhythmia).

Normal serum potassium levels are between 3.5 and 5.0 mEq/L; at least 95% of the body's potassium is found inside cells, with the remainder in the blood. This concentration gradient is maintained principally by the Na+/K+ pump.