Introduction and literature review
Collection of specimens
A hundred and twenty-seven (127) pregnant women performed high vaginal swab (HVS) tests between the months of May to July, 2013, the age range of the pregnant women studied were from 13 to 45 years old. The specimen were studied for candida species and trichomonas vaginalis infections using wet mount or direct examination with 10% Potassium hydroxide (KOH) added, and gram stain techniques. They results of 21.26 % was obtained for candida species, while 6.3% was infected with trichomonas vaginalis. The study observed that the infection rate of candida species among the pregnant women was statistically significant to that of trichomonas vaginalis, considering P≤ 0.05. The co-infection rate of the study was 0.79%. The infection of candida species of 28.8% was observed among primigravidae, while trichomonas vaginalis was 10.17%, the multigravidae registered 14.71% of candida species infection and trichomonas vaginalis was 2.94%. Therefore, the primigravidae were more infected with candida species and trichomonas vaginalis than multigravidae. The age groups of 13 to 25 years of the pregnant women were mostly infected by candida species (25.93%) and trichomonas vaginalis infection was 7.41%. The pregnant mothers at third trimester (27 to 40 weeks) were mostly attacked, making a prevalence rate of 23.81% of candida species, while trichomonas vaginalis was 9.52%.
The conclusion was that contributing factors such as douching should be avoided; indiscriminate use of antibiotics without medical supervision, and education of the pregnant women using various forms, stressing the importance of prevention and control strategies should be implemented.
Keywords: Vaginal candidiasis, Trichomoniasis, Pregnant, Women, Cape Verde.
Objective: To determine the frequency of candidiasis and trichomoniasis infections in pregnant women.
Limitations: The techniques of latex agglutination, Enzyme linked immunosorbent assay (ELISA), and cultural tests were not used in this work.
Introduction and literature review
Infections of the vulva and vagina are common among women and the most common types of vulvovaginitis are Candidiasis, trichomoniasis and bacterial vaginosis.
Candida species may be transmitted by sexual partners and may cause balanitis, balanoposthitis and rarely urethritis in men. However, for candida species to colonize the vagina, they must first adhere to the vaginal epithelial cells and then grow, proliferate, and germinate, before causing symptomatic inflammation. Changes in the vaginal environment are usually necessary before the organism can induce virulent pathological effects.
The natural bacterial flora serves as the most important defense mechanism against colonization and inflammation. The mechanism whereby candida species induces inflammation is not yet known, but essential predisposing factors for colonization and inflammation were; changes in reproductive hormone levels associated with premenstrual periods, pregnancy, oral contraceptive pills, abusive use of antibiotics and diabetes mellitus.
Chemical products, local allergy and delayed hypersensitivity can contribute to the induction of symptomatic vaginitis and vulvitis and may play a role in chronic or recurrent Candidiasis. The diagnosis of vaginal Candidiasis cannot always be confirmed on the basis of clinical symptoms alone without adequate laboratory investigations. Although, clinical suggestive diagnosis of Candidiasis includes; vaginal itching, an odorless curdy white discharge, burning sensation in the vulva region, dysuria and erythema of the labia and vulva, arriving at this, a consulting physician must rely dynamically and effectively on laboratory findings to confirm the diagnosis.
Candidiasis, an opportunistic infection is mainly caused by candida albicans, is one of the most common causes of vaginitis, Eschenbach D.A. (2004). Omar AA (2001) reported that the incidence of Candidiasis has increased markedly during the last three decades. The incidence of Candidiasis continued to double unabated in the third trimester of pregnancy and multigravida suffer significantly more than primigravida, Limia,O. F (2004). However, a significant proportion of women with chronic or recurrent Candidiasis first present with this infection while pregnant. The systems by which pregnancy encourages candida colonization are still very complex, Xu, DJ &Sobel JD (2004).
During pregnancy, levels of both progesterone and estrogen hormones are high. Progesterone has suppressive effects on the anti-candida activity of the neutrophils, Nohmi (1995), while estrogen is responsible for reducing the ability of vaginal epithelial cells to inhibit the growth of candida species and also decreases immunoglobulin in the vaginal exudates resulting in increased propensity of pregnant women to vaginal Candidiasis, Fidel (2005). It is a common gynaecologic problem that affects three out of four women in their lifetime, Das-Neves et al (2008).
Dr. Ferrer (2000) reported that more than 40% of affected women would have two or more cases of Candidiasis, with the vagina discharging smelly, thick, whitish-yellowish, itching, burning and swelling feelings presenting even in the healthiest of women. Akinbiyi et al (2008) stressed that candida vaginitis identification as a cause of disease can be a difficult task since almost 50% of asymptomatic women do have candida organisms as part of their endogenous vaginal flora, hence limitations in using clinical signs and symptoms in the diagnosis of vaginal infection. Under normal condition, candida yeast is held in check by normal body defense mechanisms together with other normal microbial flora of the body. For example, the activity of the vagina is maintained at PH 4.0 – 4.5. This acidity level prevents some vaginal microbial flora from establishing as infection. The physiological changes in the balance of the body system would affect both beneficial and harmful yeasts, bacteria and other microorganisms in the body. This would in effect alter the acidic condition of the vagina reducing it to PH 5.0 – 6.5, and this gives room for the multiplication of microorganisms such as candida, Akinbiyi et al (2008). The PH of the vagina may increase with advancing age, phase of menstrual cycle, sexual activity, birth control pills, pregnancy, presence of necrotic or apoptotic tissue or foreign bodies and use of hygienic products or antibiotics, Nyirjesy (2008).
Candidiasis infection in pregnancy does not usually harm the unborn baby, but causes great discomfort to the mother, and if untreated, the baby can get infected (oral thrush) at birth, which poses a serious health problem in premature infants. However, untreated vaginal infection can cause pelvic inflammatory disease, a condition which can scar the fallopian tube and cause infertility in women, Garcia et al (2006).
Trichomoniasis on the other hand, is an infection of the genital tract caused by a flagellated protozoon, trichomonas vaginalis. Trichomoniasis is considered mainly as sexually transmitted, non-veneral transmission is not well documented or published. Vaginal trichomoniasis may be asymptomatic in a large proportion of infected women. In women therefore, trichomoniasis elicits an acute inflammatory response resulting in vaginal discharge containing high, moderate or low numbers of polymorphonuclear neutrophils. Typical symptoms associated with trichomoniasis in women include vaginal itching or irritation and a frothy grey to green- yellow discharge, vaginal malodor and dysuria.
Trichomonas vaginalis is an ovoid, globular pear shaped flagellate, 12 to 25 µm long, with four free anterior flagella and one extra posterior flagellum attached to an undulating membrane, extending along the length of its body. However, certain signs and symptoms are predictive for trichomoniasis, the detection of the parasite is necessary to establish the diagnosis. Trichomonads are best recognized by an experienced medical laboratory scientist or technician, by their typical jerky motility in a suspended wet preparation.
The parasite is passed from an infected sexual partner to an uninfected partner during sexual intercourse. During sexual intercourse, the parasite is usually transmitted from the penis to the vagina or from vagina to penis depending on who is infected. It can also pass from vagina to another vagina. However, it is not relatively common for the parasite to infect other body parts like, the hands, mouth, and anus. It is not clear why some patients with the infection get symptoms, while others are not, but it can probably depends on factors like the person`s age and overall health condition. Although, infected people without symptoms can still pass the trichomonas vaginalis to others. Trichomoniasis can make one feel unpleasant during sex and without treatment; the infection can last for months or even years.
Despite a relative paucity of studies on the prevalence and incidence of trichomoniasis, the studies of Dr. Cates W. Jr. (1999), expressed that, trichomonas infection is one of the most common sexually transmitted diseases in the United States, with an estimated 5 million new cases each year. Although the microorganism appears to be highly prevalent and has a global geographic distribution, trichomonas has not been the focus of intensive research nor of active control programs.
Trichomoniasis is the most prevalent, non- viral, sexually transmitted infection worldwide, Shira & Frank (2006).In the United States, an estimated 3.7 million people have trichomonas vaginalis and only about 30% develop pathological signs of trichomoniasis. Infection rate is common in women than men and this risk increases with age. Although, the infection is associated with vaginitis and urethritis, the disease encircles a broad spectrum of symptoms, ranging from a severe inflammation and irritation with fruity malodorous discharge to a relatively asymptomatic carrier state. The World Health Organization estimates that 10% to 25% of vaginal infections is due to trichomoniasis, WHO (2001).
Trichomoniasis infection typically elicits an aggressive local cellular immune response with inflammation of the vaginal epithelium and exocervix in women, and the urethra of men, Sardana S. et al (1994). Trichomoniasis infection can increase the risk of transmission of Human immunodeficiency Virus (HIV), Cohen (2000). This inflammatory response induces a large infiltration of leucocytes, including HIV target cells such as CD4+ bearing T- lymphocytes and macrophages to which HIV can bind and gain access, Levine W.C et al (1998). In HIV negative person, both the leucocytes infiltration and genital lesions induced by trichomonas vaginalis may enlarge the portal of entry for HIV, by increasing the number of target cells for the virus and allowing direct viral access to the bloodstream through open lesions. Laconically, in HIV infected person, the hemorrhage and inflammation can increase the level of virus laden body fluids, the numbers of HIV infected lymphocytes and macrophages present in the genital contact area or both.
The resulting increase of both free virus and virus infected lymphocytes can expand the portal of exit, thereby increasing the chances of HIV exposure and transmission to an uninfected person. Increased cervical shedding of HIV has been shown to be associated with cervical inflammation, Kreiss, J et al (1994). Hobbs, M M et al (1999) documented substantial increased urethral viral loads in men with Trichomoniasis infection, in addition, trichomonas has the capacity to degrade secretory leukocyte protease inhibitor, a product known to block HIV cell attachment; this process may also promote HIV transmission, Draper, D et al (1998).
The cross-sectional study of Ghys P D et al (1995) among female sex workers in Abidjan, Ivory Coast, discovered an association between HIV and trichomonas infection in bivariate analysis, and the work of Ter Muelen J et al (1992) in Tanzania concluded that trichomonas infection was more common in women with HIV infection in multivariate analysis. However, these cross. Sectional studies are limited by the issue of temporal ambiguity, that is, lack of proper information on whether trichomonas infection preceded HIV. The evaluation of four hundred and thirty-one HIV negative women in Zaire by Laga M and co-workers stated that prior trichomonas infection was associated with a two fold increase rate of HIV seroconversion in a multivariate setting.
Sutton M et al (2007) reported the prevalence of Trichomonas vaginalis among women in the United States of America (USA) at 3.1% and proved that significant racial disparity exists in the USA, with black women tendency for infection with trichomonas been ten times higher than other races in the USA. This Phenomenon may indicate a high prevalence of trichomonas infection among the sex partners of these women. The association with black race in the USA may also reflect decreased use of barrier protection in this population. Alternatively, it is possible that practices such as douching, which is reportedly more common in black women, Aral S O et al (1992), and can increase susceptibility to other sexually transmission infections, Scholes D et al (1998), which in turn predispose to trichomoniasis and hence, explain the observed discrepancy racial association.
However, increased prevalence of trichomonas infection can also reflect lack of access to care and distrust of the health care system, which can manifest as failure to seek care, non-compliance with treatment recommendations, and also hesitation to refer partners for adequate treatment, drug use and its association with high risk sexual behaviors, including, but not exclusive to, trading sex for money or drugs, could also explain the racial disparity in the USA. Furthermore, compared with other racial ethnicities in the USA, a greater proportion of blacks are unmarried, divorced or legally separated, Bennett C (1993), and unmarried status is itself a risk marker for sexually transmission infections, Aral & Holmes (1989). Finally, the observed racial disparity can reflect strain differences of trichomonas, for example; if the strains that infect Afro-Americana are more likely to produce chronic, persistent infection of longer duration, higher prevalence would be observed, this scientific hypothesis has not yet been proved, again in this aspect further research is imperative.
By producing a wide array of glycosidase and cysteine proteinase enzymes, trichomonas vaginalis can easily adapt to the environment, harvesting host proteins and Deoxyribonucleic acid (DNA) for metabolism. With the propensity to cause lesions, vaginitis and acute inflammatory disease of the genital mucosa, trichomonas parasite acts as a potential catalyst in the acquisition of secondary infections including Human immunodeficiency virus (HIV) and human papillomavirus (HPV)- the organism responsible for the pathogenesis of cervical cancer, Rughooputh & Greenwell (2005).
Trichomoniasis infected pregnant mother stands the risk of adverse birth outcomes such as premature rupture of membrane, premature labour, low birth weight, and post abortion or post hysterectomy infection as well as infertility, and enhanced predisposition to neoplastic transformation in cervical tissues stated, Uneke et al (2006).
This work was conducted in the city of Porto Novo, Santo Antâo, Cape Verde and the vaginal samples were tested at the department of Medical Laboratory Science section, Central Hospital, Porto Novo.
Period of the research
The collection of the vaginal samples and testing, for the purpose of this study started on First day of May, 2013 to thirty first of July, 2013 respectively.
Choice of patients
All pregnant women attending antenatal clinic for the first time in all the regions of Porto Novo were chosen for this work, and the trimesters, age, and parity of the pregnant women were recorded.
Collection of specimens
A Total of one hundred and twenty –seven (127) pregnant women were selected and vaginal discharge was removed from the vaginal walls of the pregnant women with a swab stick, generally from the wall of the posterior fornix. In pregnant women who have only a slight discharge and extensive involvement of the vulva or labia, the specimens were collected from the irritated mucosa. The transport medium engaged was Amies to maintain viability and motility of trichomonads according to Dr.Van Dycke et al (1999). All the vaginal samples were collected voluntarily with the consent of the pregnant women and those who declined were omitted from this research.
All the samples were placed on a glass slide and depending on its fluidity; mix with a drop of physiological saline. Cover the direct preparation with a cover slip and examine microscopically at X400 magnification to detect yeast cells and presence of trichomonads. 10% Potassium hydroxide (KOH) was added to the preparation to increase the detection sensitivity of yeast cells, making the recognition of mycelia (pseudohyphae) much easier. Despite the fact that the sensitivity of wet mount is superior to that of a stained smear, all slides for this work were subjected to Gram Stain method of bacterial identification.
Gram staining techniques according to Monica Cheesbrough (2000) was applied.
Reagents used were;
Crystal violet stain
Acetone- alcohol decolorizer
Safranine or neutral red
Systematic staining techniques
Fix the dried smear with methanol for 2 minutes.
Cover the fixed smear with crystal violet stain for 60 seconds.
Wash off the stain with clean water.
Cover the smear with Lugol`s iodine for 60 seconds.
Wash off the iodine with clean water.
Decolorize rapidly (few seconds) with acetone-alcohol solution and wash immediately with clean water.
Cover the smear with Safranine or neutral red stain (counterstain) for 2 minutes.
Wash off the stain with clean water, wipe the back of the slide with clean gauze, allow to air dry in draining rack.
Examine microscopically for gram positive yeast cells.
illustration not visible in this excerpt
Figure A: Binocular Microscope in medical laboratory environment.