**4.5** *Neisseria gonorrhoeae*

their ability to induce protection (Cruz-Fisher *et al.,* 2011).

*N. gonorrhoeae* has been implicated in tubal infections. Both the bacteria themselves or components of the bacterial cell wall, lipopolysaccharide or peptidoglycan reportedly cause cessation of the ciliary activity (Mardh 1979) however, infection of the Fallopian tubes does not always result in ultrastructural damage to the mucosal surface (Woods & McGee 1986). Gonococci only invade the non-ciliated cells of the Fallopian tube mucosa, whereby the neighbouring ciliated cells become sloughy and detached (McGee 1981). *Neisseria* spp. infection of the Fallopian tubes results in a dose-dependent response to bacterial cells. Low numbers of bacterial cells induce secretion of TNF-α and subsequently apoptosis of infected cells, however, when bacterial cell numbers increase, the apoptosis appears to be inhibited, favouring bacterial survival (Dean and Powers, 2001). Studies have suggested that ectopic pregnancy is now more likely to be associated with non-gonococcal rather than *N*. *gonorrhoeae* upper genital tract infection (Kamwendo *et al.,* 1996).

#### **4.6 Mycoplasma species**

*M. hominis* reportedly causes ciliostasis and swelling of Fallopian tube cilia (Mardh & Westrom 1970). *Mycoplasma* spp. have been isolated from the female upper genital tract and Fallopian tubes (Cohen 2005; Heinonen & Miettinen 1994; Stagey *et al* 1992). Serological testing of women has confirmed an association between mycoplasmas and cases of PID (Moller *et al.,* 1985)and mycoplasma, PID and ectopic pregnancy (Jurstrand *et al.,* 2007). A prospective study of 212 infertile couples was undertaken to investigate the presence of

Tubal Damage, Infertility and Tubal Ectopic Pregnancy:

infertility and tubal ectopic pregnancy.

summarised in Table 1.

**5. Ectopic pregnancy and chlamydia** 

*Chlamydia trachomatis* and Other Microbial Aetiologies 27

Based on previous studies, it has been concluded that genital tract infections including salpingitis, which causes tubal factor infertility are polymicrobial in nature. Furthermore, a diverse range of microorganisms are capable of colonising and possibly infecting the genital tract tissues. Opportunistic pathogens identified in genital tract infections are frequently members of the normal regional flora and should be further investigated given that 60% of PID is non-gonococcal and non-chlamydial. Infectious causes of salpingitis and tubal factor infertility require further investigation to better establish prevalence and causality. The identification of microorganisms that are particularly detrimental to the Fallopian tubes may result in effective treatment and a reduction in the overall frequency of tubal factor

Infectious agents cause damage to the Fallopian tube mucosa either directly or because of the host inflammatory response aimed at clearing the infection. Alteration to the mucosa can result in poor transport of the embryo and subsequent implantation of the blastocyst outside the endometrial lining of the uterine cavity – an ectopic pregnancy. Tubal ectopic pregnancy is a result not only of impaired transport of the embryo causing the embryo to be maintained in the Fallopian tube but also a result from alterations in the tubal environment that allows early implantation to occur (reviewed in Shaw *et al.,* 2010). A recent review also summarises the results of investigations of the Fallopian tube with respect to the roles of of caspase 1, cannabinoid receptor and Dicer 1 knockout mice and how these contribute to

A recent review highlighted the many risk factors for ectopic pregnancy and these are

Risk Factors for ectopic pregnancy *High risk*

*Moderate risk*

*Low risk*

Table 1. Risk Factors for ectopic preganacy (adapted from Kulp and Barnhart, 2008)

tubal dysfunction and contribute to ectopic pregnancies (Shao 2010).

Previous ectopic pregnancy

Use of intrauterine devices

**Previous genital infections**  Multiple sexual partners Salpingitis isthmica nodosa

Previous pelvic infection Cigarette smoking Vaginal douching

First intercourse (<18 years)

*In utero* exposure to diethylstilbestrol

Tubal surgery Tubal Ligation

Tubal pathology Assisted reproduction

Infertility

*M.genitalium* in women with tubal factor infertility and it was found that antibodies to *M.genitalium* were shown to be independently and significantly associated with tubal factor infertility (Svenstrup *et al.,* 2008).

Recently it has been reported that a genetic polymorphism in one of the components of the inflammasome - a cytoplasmic structure producing interleukin-1 - increases the likelihood of mycoplasma infection-associated female infertility (Witkin *et al.,* 2010).

#### **4.7** *Ureaplasma spp.*

*Ureaplasma* spp. have been implicated in infections of the lower (bacterial vaginosis) and of the upper genital tracts (PID, endometritis) of women (Kanakas *et al* 1999). Further, tubal infertility has been associated with ureaplasma PID in a small number of cases (Henry-Suchet *et al* 1980. Inoculation of *Ureaplasma* spp. into *in vivo* Fallopian tube organ cultures resulted in replication of the pathogen, suggesting that this genital mycoplasma may also play a role in tubal damage.

#### **4.8 Anaerobic bacteria**

Anaerobic species are frequently isolated from the female genital tract and in cases of acute PID (Saini *et al* 2003). The polymicrobial nature of anaerobic infections appears to enhance the pathogenicity of the implicated species implicated (Eschenbach et al 1975). Previous upper genital tract pathology caused by upper genital tract infections, pelvic adhesions, endometriosis or prolonged or continuous menstruation, have been associated with the reactivation of PID. It is likely that the compromised areas of the pelvic cavity promote the establishment of a niche for bacterial survival (El-Shawarby *et al* 2004). Ness *et al*. (2005) reported that the presence of anaerobic bacterial vaginosis-associated microorganisms in the vagina was a significant risk factor for infection of the upper genital tract leading to longterm sequelae and possible PID.

*Mobiluncus* spp*.* are frequently isolated from women with bacterial vaginosis. Members of the *Mobiluncus* genera have been shown to produce cytotoxins, resulting in the loss of cilia, and bloating and detachment of the ciliated cells of the Fallopian tube mucosa (Taylor-Robinson *et al* 1993). Another of the genera associated with bacterial vaginosis, the gram-negative *Bacteroides* spp*.* also releases lipopolysaccharide, resulting in the sloughing of Fallopian tube epithelial cells and loss of ciliary activity within the Fallopian tubes (Fontaine *et al* 1986).

#### **4.9 Aerobic/Microaerophilic bacteria**

Gram-positive species, *Enterococcus* spp., *Staphylococcus* spp., and *Streptococcus* spp. have been isolated from Pouch of Douglas aspirates of a polymicrobial microflora in women with symptoms of genital tract infection (Saini et al 2003). Saini *et al*. (2003) proposed that the microflora of the Pouch of Douglas was likely to be more representative of Fallopian tube microorganisms in women with salpingitis than the vaginal flora of those same women.

Members of the Enterbactereaceae have been detected in upper genital tract infections. The Gram-negative bacillus, *Klebsiella* spp. are frequently isolated from women with PID (Saini et al., 2003). Laufer *et al.,*. ((Laufer *et al.,* 1984)) reported that inoculation of the Fallopian tubes with *Escherichia coli* resulted in complete de-ciliation or damage to the cilia. When damage occurred, the cilia were swollen and short. In addition, microvilli were lost from the non-ciliated cells. The oxidative species, *Pseudomonas aeruginosa* is also a causal agent of PID in females (King *et al.,* 2002).

*M.genitalium* in women with tubal factor infertility and it was found that antibodies to *M.genitalium* were shown to be independently and significantly associated with tubal factor

Recently it has been reported that a genetic polymorphism in one of the components of the inflammasome - a cytoplasmic structure producing interleukin-1 - increases the likelihood of

*Ureaplasma* spp. have been implicated in infections of the lower (bacterial vaginosis) and of the upper genital tracts (PID, endometritis) of women (Kanakas *et al* 1999). Further, tubal infertility has been associated with ureaplasma PID in a small number of cases (Henry-Suchet *et al* 1980. Inoculation of *Ureaplasma* spp. into *in vivo* Fallopian tube organ cultures resulted in replication of the pathogen, suggesting that this genital mycoplasma may also

Anaerobic species are frequently isolated from the female genital tract and in cases of acute PID (Saini *et al* 2003). The polymicrobial nature of anaerobic infections appears to enhance the pathogenicity of the implicated species implicated (Eschenbach et al 1975). Previous upper genital tract pathology caused by upper genital tract infections, pelvic adhesions, endometriosis or prolonged or continuous menstruation, have been associated with the reactivation of PID. It is likely that the compromised areas of the pelvic cavity promote the establishment of a niche for bacterial survival (El-Shawarby *et al* 2004). Ness *et al*. (2005) reported that the presence of anaerobic bacterial vaginosis-associated microorganisms in the vagina was a significant risk factor for infection of the upper genital tract leading to long-

*Mobiluncus* spp*.* are frequently isolated from women with bacterial vaginosis. Members of the *Mobiluncus* genera have been shown to produce cytotoxins, resulting in the loss of cilia, and bloating and detachment of the ciliated cells of the Fallopian tube mucosa (Taylor-Robinson *et al* 1993). Another of the genera associated with bacterial vaginosis, the gram-negative *Bacteroides* spp*.* also releases lipopolysaccharide, resulting in the sloughing of Fallopian tube

Gram-positive species, *Enterococcus* spp., *Staphylococcus* spp., and *Streptococcus* spp. have been isolated from Pouch of Douglas aspirates of a polymicrobial microflora in women with symptoms of genital tract infection (Saini et al 2003). Saini *et al*. (2003) proposed that the microflora of the Pouch of Douglas was likely to be more representative of Fallopian tube microorganisms in women with salpingitis than the vaginal flora of those same women. Members of the Enterbactereaceae have been detected in upper genital tract infections. The Gram-negative bacillus, *Klebsiella* spp. are frequently isolated from women with PID (Saini et al., 2003). Laufer *et al.,*. ((Laufer *et al.,* 1984)) reported that inoculation of the Fallopian tubes with *Escherichia coli* resulted in complete de-ciliation or damage to the cilia. When damage occurred, the cilia were swollen and short. In addition, microvilli were lost from the non-ciliated cells. The oxidative species, *Pseudomonas aeruginosa* is also a causal agent of PID

epithelial cells and loss of ciliary activity within the Fallopian tubes (Fontaine *et al* 1986).

mycoplasma infection-associated female infertility (Witkin *et al.,* 2010).

infertility (Svenstrup *et al.,* 2008).

**4.7** *Ureaplasma spp.*

play a role in tubal damage.

term sequelae and possible PID.

**4.9 Aerobic/Microaerophilic bacteria**

in females (King *et al.,* 2002).

**4.8 Anaerobic bacteria**

Based on previous studies, it has been concluded that genital tract infections including salpingitis, which causes tubal factor infertility are polymicrobial in nature. Furthermore, a diverse range of microorganisms are capable of colonising and possibly infecting the genital tract tissues. Opportunistic pathogens identified in genital tract infections are frequently members of the normal regional flora and should be further investigated given that 60% of PID is non-gonococcal and non-chlamydial. Infectious causes of salpingitis and tubal factor infertility require further investigation to better establish prevalence and causality. The identification of microorganisms that are particularly detrimental to the Fallopian tubes may result in effective treatment and a reduction in the overall frequency of tubal factor infertility and tubal ectopic pregnancy.
