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Trichomoniasis (n. pl. trich·o·mo·ni·a·ses) is the most common non viral sexually transmitted disease in the world.

According to the World Health Organization's annual estimates, there are an estimated 7.4 million trichomoniasis cases each year in the United States, with over 180 million cases reported worldwide

Trichomoniasis is caused by the parasitic protozoan Trichomonas vaginalis, which infects both men and women. There has been a growing body of data implicating trichomoniasis as a contributor to health complications among both women and men.

Organism

Trichomonas vaginalis is a pear-shaped, flagellate, motile protozoan, with an undulating membrane. It is about 10-20µm wide, and is ovate. The organism is propelled by four anterior flagella with a flagellum attached to an undulating membrane (Heine, 1993). T. vaginalis is anaerobic and does not contain mitochondria in its cytoplasm, but instead contains specialized granules called hydrogenosomes throughout the region of the cytoplasm. The morphology of T. tenax and T. hominis differ from T. vaginalis in that the trailing flagellum of the protozoa extends past the organism's undulating membrane

Pathogenesis

Although trichomoniasis is the most common non-viral sexually transmitted disease, the pathogenicity of T. vaginalis is not thoroughly understood. Trichomonads participate in a host-parasite relationship, causing them to adhere to epithelial cells. The ability of trichomonads to adhere is affected by time, temperature, and pH level. T. vaginalis grows best in an anaerobic environment with a pH > 6 (Diamond LS, 1986). T. vaginalis binding to vaginal epithelial cells for colonization and infection is dependent upon specific parasite surface proteins. Parasites treated with metronidazole or other nitroimidazoles lose their ability to adhere, making them ineffective disease agents. Hemolysis, the destruction of red blood cells such that hemoglobin is released, is also correlated with virulence. Trichomoniasis has been seen to increase in severity during or slightly after menstruation (Graves, 1993).

The relationship between T. vaginalis growth and protective lactobacilli is a complex one. It is currently unknown whether TV infection alters the vaginal environment by creating an anaerobic situation or if anaerobes in the vagina precede TV growth. The vagina contains glycogen, especially rich in reproductive aged women. Glycogen is broken down into glucose, a nutrient T. vaginalis requires for growth

Several risk factors for acquisition of the organism have been identified, including multiple sexual partners, black race, history of previous STD and coexistent infection with Neisseria gonorrhoeae (Sobel, 1997). Approximately 8% to 50% of patients with T. vaginalis have concomitant infections. T. vaginalis often coexists with Bacterial Vaginosis. Trichomoniasis was associated with the presence of bacterial vaginosis in a study of 871 HIV-seropositive women and 439 HIV-seronegative women in the HIV Epidemiology Research Study (Cu-Uvin, 2002). T. vaginalis was present in 74% of women with BV vs. 35% of women without BV (p=.02).

Due to T. vaginalis' anaerobic characteristics, the organism's growth is enhanced at elevated pH levels. T. vaginalis grows over a wide pH range of 3.5-8. However, a vaginal pH below 4.5 decreases motility. Therefore a vaginal pH above 4.5 would be conducive to infection (Thomason, 1989). Failure to use barrier contraceptives increases an individual's susceptibility to infection.

MOT

nfection of the genitourinary tract occurs through sexual transmission. Evidence for sexual transmission of T. vaginalis is very strong as prevalence is highest among patients with increased sexual activity and multiple partners. Approximately 14-65% of male partners of infected females are also infected (Krieger, 1995, Sena, 2003). The incubation period before symptoms arise is 4-28 days in approximately 50% of infected women (Weston, 1963). Asymptomatically infected individuals are in important vector and act as a stealth factor in trichomoniasis transmission. Many studies have shown that treatment of the male partner(s) of infected women improves both cure rates and recurrence rates (Hager 1980, Lyng, 1981).

Live T. vaginalis organisms in urine and semen samples have been found after being exposed to air for several hours. Also, organisms are able to survive for hours on damp towels and clothes of infected women (Lossick, 1989). There have been no well-documented cases regarding transmission through the aforementioned means. Nonsexual transmission is extremely rare since T. vaginalis infection is generally restricted to a specific site, namely the urogenital tract (Thomason, 1989). The only known nonvenereal form of transmission is through perinatal acquisition. Approximately 5% of female babies born of infected mothers contract the infection (Bramley, 1976).

SITES

T. vaginalis infection is generally confined to the urogenital tract. There have, however, been rare reports of trichomonads being found in other sites such as the lungs and cerebrospinal fluid. These cases have usually been accompanied by a severe underlying disease. Rarely have the organisms been identified as T. vaginalis, but were most likely T. tenax or T. hominis (Rein, 1990).

Recently, a 41 year old HIV+ male was hospitalized due to fever and dyspnea. A cytologic examination of his bronchoalveolar lavage fluid revealed numerous T. vaginalis organisms. This is the first case where T. vaginalis was found in the lungs of an adult. Data collected suggest that trichomonads are overlooked parasites and may be implicated in various human pathologies (Duboucher, 2003).

Sites - Women

T. vaginalis organisms may be isolated from the cervix, vagina, Bartholins glands, bladder, urethra and occasionally the upper reproductive/urinary tract (Rein, 1990). Over 95% of infections have been isolated from the vagina and only 5% from the urinary tract of adult women (Grys, 1964). The urethra and Skene's glands are infected in 90% of cases. There have also been instances where organisms were isolated from bladder urine (Thomason, 1989). T. vaginalis may also act as a carrier for other pathogenic organisms. Keith conducted an in vitro study in 1986 to observe the attachment between T. vaginalis and other bacteria that inhabit the urogenital areas. Using scanning electron microscopy, one finding displayed a cluster of cocci attached to a trichomonad and two other demonstrated multiple cocci and E. coli attached to a T. vaginalis organism. Trichomonads have been shown to migrate to the fallopian tubes and peritoneal cavity. Thus, by carrying bacteria or viruses on their surfaces, it is possible that T. vaginalis organisms contribute to upper genital tract infections (Keith, 1986).

In 2003, Rendón-Maldonado, et al. cited that STDs caused by bacteria and protozoa are important factors in the epidemiology of HIV-1. The research team incubated three subtypes of HIV-1 (A, B, and D) with HIV-1 infected lymphocytes and observed the interactions with immunofluorescence microscopy and transmission electron microscopy. Results showed that trichomonads may internalize HIV-1 particles for a short time period. Under in vitro conditions, trichomonads ingest and digest HIV-1 infected lymphocytes (Rendón-Maldonado, et al., 2003).

Results of a study by Pindak (1989), also indicate that viruses may be transmitted by T. vaginalis. Virus containing cell fragments were engulfed by trichomonads and internalized in vacuoles. Viable reoviruses were recovered from the trichomonads for nine days and genital herpes simplex virus for six days, suggesting the possibility of transmission of viruses by T. vaginalis (Pindak, 1989).

Sites - Men

In men the urethra is the most common site for T. vaginalis infection. Organisms can also be detected in the epididymis, semen, and urine (Krieger, 1981). T. vaginalis was first located in prostatic fluid by Drummond who examined prostatic secretions from husbands of infected women (Drummond, 1936).

S/S FM

In women, the infection is often characterized by a yellow-green, frothy vaginal discharge, vaginal odor, pain with sexual intercourse, pain with urination, and vulvovaginal soreness and itching (Rein, 1990). Common clinical signs include vulvar erythema, inflammation, excess of white blood cells seen on a wet mount preparation of vaginal discharge, motile trichomonads in the wet mount preparation, and a vaginal pH above 5, most of which overlap with BV signs and symptoms, complicating diagnosis. The following is a differential diagnosis chart comparing several vaginal infections.

S/SM

In men, the infection is more difficult to detect as the majority of infections remain asymptomatic and readily available diagnostic techniques are inadequate. This is problematic since long term carriage of T. vaginalis in asymptomatic men has been documented up to 4 months (Krieger, 1993). Most men seeking treatment do so because of an infected partner (Hager, 1994).

Symptoms in men typically include urethral discharge, dysuria, mild pruritis, or burning after intercourse. Forty percent of symptomatic males have infected prostate glands. Men who are unresponsive to antimicrobial therapy for nonspecific urethritis should be tested for T. vaginalis since 15-20% will be infected with the organism (Thomason, 1989, Schwebke, 2003). The following table summarizes common symptoms found in T. vaginalis infected men.

RISK

Recently, a growing body of literature has linked T. vaginalis infection to a variety of health complications among both men and women. Among both women and men, T. vaginalis is emerging as one of the most important factors in transmission and acquisition of HIV infection (Sorvillo, 1998). In women, the health complications include increased risks for the following: infertility, development of atypical pelvic inflammatory disease, infection following gynecologic surgery, and cervical inflammatory neoplasia. There have also been high rates of correlation between trichomoniasis and pregnancy complications in women. In men, T. vaginalis has been linked to male factor infertility and as a common cause of non-gonococcal urethritis (NGU) (Schwebke, 2002, Soper, 2004).

Trichomoniasis as a Risk Factor for Cervical Neoplasia

The association between T. vaginalis and cervical neoplasia has been reported in many studies since the early 1950s. It has been suggested that this organism is responsible for the induction of changes in the human cervical mucosa resulting in dysplasia or carcinoma (Bechtold, 1952). A prospective, longitudinal cohort study followed over 19,000 women in Finland in a mass cervical cancer screening program for up to a 10 year period, to determine if women with cytologically diagnosed infections (T. vaginalis, herpes, or HPV) preceded development of cervical neoplasia. T. vaginalis was shown to be associated with a high relative risk (OR 6.4) of subsequent CIN. This was similar to risks found with either HPV (OR = 5.5) or herpes infection (OR = 12) and development of subsequent CIN (Viikki, 2000).

Zhang (1994) conducted a combined analysis of 2 cohort and 22 case-control studies examining the association between T. vaginalis infection and cervical neoplasia. The results from the analysis indicated that T. vaginalis is associated with increased risk of cervical neoplasia. The following table is a summary of the 24 studies used in Zhang's data analysis.

Breastfeeding is the feeding of an infant or young child with milk from a woman's breasts. Babies have a sucking reflex that enables them to suck and swallow milk.

Experimental evidence suggests that, with few exceptions, human breast milk is the best source of nourishment for human infants. Experts still disagree about how long breastfeeding should continue to gain the most benefit, and how much extra risk is involved in using breast milk substitutes. An infant may be breastfed by its own mother or by another lactating female, a wet nurse. Breast milk may be expressed (such as with a breast pump) and fed to a baby through a bottle, and pasteurized donor human milk may also be used. The pasteurization process on human breast milk, such as for donation purpose, is known to destroy most nutritional content and renders the donor milk of questionable benefit compared to fortified infant formulas. Breast milk substitutes are available for mothers or families who cannot or prefer not to breastfeed their children. While there are conflicting studies about the relative value of breast milk substitutes, the use of commercial infant formulas is acknowledged to be inferior to breastfeeding for both full term and premature infants. In many countries, artificial feeding is associated with a greater mortality from diarrhoea in infants but where there is clean water, many consider artificial feeding to be acceptable.

Governmental strategies and international initiatives promote breastfeeding as the best method of feeding infants in their first year and beyond. The World Health Organization (WHO) and the American Academy of Pediatrics (AAP) also promote breastfeeding

Breastmilk

The exact properties of breast milk are not entirely understood, but the nutrient content of mature milk is relatively stable. Its ingredients come from the mother's food supply and the nutrients in her bloodstream at the time of feeding. If that is not enough, nutrients come from the mother's bodily stores. Some studies estimate that a woman who breastfeeds her infant exclusively uses 500–600 more calories a day just producing milk for her offspring. The exact composition of breast milk varies from day to day, and even hour to hour, depending on both the manner in which the baby nurses and the mother's food consumption and environment, so the ratio of water to fat fluctuates.

Foremilk, the milk released at the beginning of a feed, is watery, low in fat and high in carbohydrates; hindmilk, which is increasingly released as the feed progresses is creamier. There is no sharp distinction between foremilk and hindmilk, the change is very gradual. Research from Peter Hartmann's group tells us that fat content of the milk is primarily determined by the emptiness of the breast—the less milk in the breast, the higher the fat content. The breast can never be truly "emptied" since milk production is continuous.

Breastfeeding benefits both mother and child physically and psychologically. Nutrients and antibodies are passed to the baby while hormones are released into the mother's body. The bond between baby and mother can also be strengthened during breastfeeding.

Benefits for the infant

Breastfed babies have a lower risk of sudden infant death syndrome (SIDS) and other diseases. Suckling at the breast encourages the proper development of the infant's teeth and speech organs. Suckling also helps prevent obstructive sleep apnea. Also, breast milk is at the right temperature and is immediately available from the breast.

Breastfeeding is associated with lower risk of the following diseases:

1. Allergies
2. Asthma
3. Autoimmune thyroid diseases
4. Bacterial meningitis
5. Breast cancer
6. Celiac disease
7. Crohn's disease
8. Diabetes
9. Diarrhea
10. Eczema
11. Gastroenteritis
12. Hodgkin's lymphoma
13. Necrotizing enterocolitis^[
14. Multiple sclerosis
15. Obesity
16. Otitis media (ear infection)
17. Respiratory infection and wheezing
18. Rheumatoid arthritis
19. Urinary tract infection

Breast milk has several anti-infective factors. These include the anti-malarial factor para-amino benzoic acid (PABA), the anti-amoebic factor BSSL, , lactoferrin, the second most common protein in human milk, that binds to iron and inhibits the growth of intestinal bacteria like E. coli and Salmonella, and IgA which protects breastfeeding infants from microbial infection. Breast milk contains the right amount of the amino acids cystine, methionine and taurine that are essential for neuronal (brain and nerve) development. A New Zealand study tracking over 1000 children for 8 to 18 years found small but measurable increases in cognitive ability and education achievement. This remained even after adjusting for other factors (such as maternal education level).

One study suggests that in resource-poor settings where safe infant formula is unavailable, exclusive breastfeeding (as compared with "mixed" feeding where breastfeeding is combined with formula, solids or animal milk) may reduce the risk of HIV transmission from mother to child in infants less than 6 months old.

Unlike human milk, the predominant protein in cow's milk is beta-lactoglobulin, an important factor in cow milk allergies.

Benefits for the mother

Breastfeeding benefits the mother. It releases hormones such as oxytocin and prolactin that have been found to relax the mother and make her feel more nurturing toward her baby. Breastfeeding within a short time after giving birth increases levels of systemic oxytocin. This makes the uterus contract more quickly and decreases maternal bleeding.

As the fat accumulated during pregnancy is used in milk production, prolonged breastfeeding can help mothers to return to their previous weight. Frequent and exclusive breastfeeding can cause lactational amenorrhea, a delay in the return of menstruation and therefore fertility. Sometimes this is deliberately used as a birth control method, which has a 98% success rate if certain criteria are met:

• Breastfeeding must be the infant’s only (or almost only) source of nutrition. Feeding formula, pumping instead of nursing, and feeding solids all reduce the effectiveness of LAM.
• The infant must breastfeed at least every four hours during the day and at least every six hours at night.
• The infant must be less than six months old.
• The woman must not have had a period after 56 days post-partum (when determining fertility, bleeding prior to 56 days post-partum can be ignored).

Breastfeeding is possible throughout pregnancy, but generally milk production will be reduced at some point during the pregnancy.

Breastfeeding mothers have less risk of many diseases including breast cancer, ovarian cancer, decreased insulin requirements in diabetic mothers, stabilizing maternal endometriosis, less risk of post-partum hemorrhage, less risk of endometrial cancer, less risk of osteoporosis and beneficial effects on insulin levels of mothers with polycystic ovary syndrome.

Mothers who breastfeed longer than eight months have better bone re-mineralisation.

On the other hand, some breastfeeding women have pain from thrush or staph infections of the nipple.

From a financial standpoint, breastfeeding is roughly half the cost of infant formula.

Bonding

The hormones released during breastfeeding strengthen the mother's nurturing feelings towards the child. Strengthening the maternal bond is very important as up to 80% of mothers suffer from some form of postnatal depression, though most cases are very mild. The woman's partner and other caregivers can support her in a variety of ways and this support is an important factor in successful breastfeeding. Teaching partners how to manage common difficulties is associated with higher breastfeeding rates.

Breastfeeding can have an impact on the personal relationship between a mother's partner and the child. While some partners may feel left out when the mother is feeding the baby, others see it as an opportunity for strengthening family bonds. Looking after a new baby and breastfeeding take time. This can add pressure to the partner and the family, because the partner has to care for the mother as well as performing tasks she would otherwise do. However, as partners are often very willing to give this support, this pressure can help to strengthen family bonds.

If the mother is away, an alternative caregiver may be able to use expressed breast milk (EBM) to feed the baby. The various breast pumps available for sale and rent make it possible for working mothers to breastfeed their babies for as long as they want. However, the mother must produce and store enough milk to feed the child for the time she is away and this may not always be practical. Also, the other caregiver must be comfortable in handling breast milk. These two factors may prompt the mother - perhaps against her wishes - to switch to artificial feeding, either temporarily or permanently.

Breastfeeding complications

Despite being a natural human activity, there are cases where breastfeeding can be difficult or contraindicated.

While breastfeeding difficulties are not uncommon, putting the baby to the breast as soon as possible after birth helps to reduce them greatly. The AAP breastfeeding policy says: Delay weighing, measuring, bathing, needle-sticks, and eye prophylaxis until after the first feeding is completed. Many breastfeeding difficulties can be resolved with proper hospital procedures, properly trained nurses and hospital staff, and lactation consultants.

Breastfed infants generally gain weight according to the following guidelines:

0–4 months: 170 grams per week^†

4–6 months: 113–142 grams per week

6–12 months: 57–113 grams per week

^† It is acceptable for some babies to gain 113–142 grams (4–5 ounces) per week. This average is taken from the lowest weight, not the birth weight.

The average breastfed baby doubles birth weight in 5–6 months. By one year, the typical breastfed baby will weigh about 2½ times birth weight. At one year, breastfed babies tend to be leaner than bottle fed babies. By two years, differences in weight gain and growth between breastfed and formula-fed babies are no longer evident.

Exclusive Breastfeeding

Exclusive breastfeeding is when an infant receives no other food or drink, or even water, besides breast milk (whether expressed or through breastfeeding).

International guidelines recommend that all infants be breastfed exclusively for the first six months of life. While each country has its own policy regarding infant feeding, it is generally accepted that newborns should be exclusively breastfed for around 6 months, and that breastfeeding should continue with the addition of appropriate foods, for two years or more. The practice of exclusive breastfeeding has dramatically reduced infant mortality in developing countries due to a reduction in diarrhea and infectious diseases.

Exclusively breastfed infants feed, anywhere from 6 to 14 times a day. Their requirements vary greatly. Newborns consume from 30 to 90 ml (1 to 3 US fluid ounces). After the age of four weeks, babies consume about 120ml (4 US fluid ounces) per feed. Each baby is different, and as it grows the amount will increase. It is important to recognise the baby's hunger signs and it is advised that the baby should dictate the number, frequency, and length of each feed, based on the assumption that it knows how much milk it needs. The supply of milk in the breast is determined by the frequency and length of these feeds or the amount of milk expressed. The birth weight of the baby may affect its feeding habits, and mothers may be influenced by what they perceive its requirements to be. For example, a baby born small for gestational age may lead a mother to believe that her child needs to feed more than if it larger; they should, however, go by the demands of the baby rather than what they feel is necessary.

It can be hard to accurately measure the amount of food a breastfed baby consumes, but babies normally feed to meet their own requirements. Babies that fail to eat enough may exhibit symptoms of failure to thrive. If necessary, it is possible to estimate output from wet and soiled nappies (diapers): 8 wet cloth or 5–6 wet disposable, and 2–5 soiled per 24 hours suggests an acceptable amount of input for newborns older than 5–6 days old. After 2–3 months, stool frequency is a less accurate measure of adequate input as some normal infants may go up to 10 days between stools. Babies can also be weighed before and after feeds.