ABSTRACT Introduction: Antisperm antibodies (ASA) prevalence is high in Kisangani. ASA are one
of the male factors of infertility that can reduce spermatozoa motility and
cervical penetration or prevent acrosomal reaction and even alter embryo
development. This study aims to
determine the risk factors of ASA positivity among infertile men in Kisangani. Patient
and Method: We conducted a case-control study during a period of 2 years in
Kisangani on 111 men who consulted for conception and tested for ASA by ELISA.
We did a simple pairing that concerned only the type of infertility. For a
better balance between the number of cases and controls per stratum to provide
better accuracy in the adjusted OR estimate, we performed a 1:1 match. Results: This study showed that businessmen [ORa = 5.0000(1.2452 - 20.0767)] and jobless
[ORa = 5.8125(1.1477 - 29.4367)] were at risk of being positive for ASA. Violent
blow to testicles [ORa = 6.7391(1.3455 - 33.7545)], cure of hernia [ORa =
4.3478(1.0722 - 17.6299)], Chlamydia infection [ORa = 4.7125(1.3405 - 16.5665)],
leucospermia [ORa = 4.1429(1.0406 - 19.7155)] and
presence of Staphylococcus aureus [ORa = 3.4444(0.6410 - 18.5082)] were
associated to positive ASA. Conclusion: This study shows that factors
that may lead to risky sexual behavior and physical or infectious trauma are
important risk factors for ASA positivity. It is therefore necessary to search
for them systematically during male infertility in order to guide the search
Infertility is a disease defined by the lack of clinical conception after 12 months or more of unprotected sexual intercourse, satisfactory in quantity and quality and at appropriate times or after treatment with insemination using donor sperm    . Failure to conceive can lead to stress, depression, discrimination, ostracism, economic problems...    . For the man, his inability to conceive often means that his virility and sexual power are affected. In African culture it is heavy to carry infertility, especially since the father transmits his name   . “Male factor” infertility is seen as an alteration in sperm concentration and/or motility and/or morphology in at least one sample of two sperm analyses, collected 1 and 4 weeks apart  . Infertility due to male factor ranges from 20% to 70% and the percentage of infertile men ranged from 2.5% to 12%. Africa and Central/Eastern Europe are the regions having the highest rate of male Infertility  . Males with sperm parameters below the WHO normal values are considered to have male factor infertility. The most significant of these are low sperm concentration (oligospermia), poor sperm motility (asthenospermia), and abnormal sperm morphology (teratospermia). As high as 90% of male infertility problems are related to count and there is a positive association between the abnormal semen parameters and sperm count    . Among factors that lead to alteration of sperm parameters, there are anti-sperm antibodies (ASA). They induce a decrease in motility of spermatozoa and their cervical penetration by agglutination. They also inhibit the acrosomal reaction by disturbing the membrane permeability of spermatozoa and they can even prevent the development of the embryo resulting in abortions. By attaching themselves to spermatozoa, ASA facilitate their recognition and phagocytosis by macrophages leading to oligospermia  -  . Globally the prevalence of ASA varies a lot around the world and can reach 64.4%      . In man, Maria Khatoon and Col.  found 30.3% of seropositivity in infertile men and B.I Adejumo et al.  found 22.7%. Maindo and Col. in Democratic Republic of Congo found a prevalence of 29.72%  . Many factors have been cited as leading to the production of ASA. Among those factors, there is testicular trauma, cryptorchidism, hernia, infections, vasectomy,…  -  .
The aim of this study is to determine risk factors of ASA positivity among infertile men in Kisangani.
2. Patients and Method
During the period of 2 years, from 1 January 2017 to 31 December 2018, we conducted a case-control study on 111 male patients who consulted for conception and in whom the search for circulating ASA in serum was performed. Apart from that, their medical files should have all data needed for this paper. For ASA search, approximately 5 ml of the venous blood from each of the 111 patients was collected under an aseptic condition. For the separation of serum from whole blood, a centrifugation at 3000 rpm was performed for 5 minutes. Once the serum was obtained, the analysis was performed immediately. If this was not possible, the sample was kept in a sterile tube at a temperature of 2˚C - 8˚C until the time of analysis. The immunoglobulin test was performed by ELISA using the Stat Fax® 4700 device. All the tests were carried out in the Ema Esu laboratory, the only one carrying out this test in the city. Patients with positive ASA serology for Ig A and/or Ig G were considered as cases and those with a negative serology were considered as control. We did a simple pairing that concerned only the type of infertility. For a better balance between the number of cases and controls per stratum to provide better accuracy in the adjusted OR estimate, we performed a 1:1 match. We included in this study infertile men with ASA research result and a medical file having necessary parameters studied in this paper. We excluded those who were in a relationship for less than 12 months and who had a medical file lacking data studied in this paper. Data were collected from medical and laboratory files were encoded using Excel. We used Epi Info® software version 7.2 for data analysis.
To measure whether there was an association between the presence of a factor and the occurrence of an event and to evaluate the degree of this association, we performed a multivariate analysis with conditional logistic regression by calculating the adjusted Odd Ratio (ORa), and its 95% confidence interval (CI).
Table 1 shows that the majority of patients were had 41 years and over (50.45%), were married (91.89%), were civil servants (53.15%) and had university level (40.54%). In Table 2, according to clinical characteristics, the majority of patients in our study had primary infertility (61.26%) with mean infertility duration of 7.33 ± 5.06 years. In their history, 13.51% had a violent testicle blow, 17.12% had cure of hernia and 4.50% had testicular torsion. There is a history of STIs among 23.42% of them. 5.41% of them have syphilis, 20.72% have chlamydia and 6.31% are positive for HIV. 61.26% of them had a spermogram abnormality. Spermogram abnormalities observed were asthenospermia (44.44%), oligospermia (37.84%), teratospermia (36.04%) and pyospermia (15.32%). Sperm culture revealed the presence of C. albicans alone in 6.31% of cases, C. albicans associated with S. aureus in 9% of cases and S. aureus alone in 9% of cases.
Table 1. Socio-demographics characteristics of patients.
*Mean duration of infertility = 7.33 ± 5.06 years; #STDs (sexually transmitted diseases) studied are C. trachomatis, Syphylis and HIV.
As show us results in Table 3, we did not found an association between the level of study and ASA, yet according to profession, we found that being businessman or jobless multiplied respectively by 5 and almost 6 the risk of ASA positivity.
In Table 4, we found that duration of infertility was not associated to ASA positivity. History of testicular trauma was found multiplying by 6 the risk of ASA positivity and among testicular trauma, violent blow to the testicles and cure of hernia multiplied by 6.7 and 4.3 the risk of ASA positivity respectively. Past or current s sexual transmitted diseases multiply by 4.1 the risk of positive ASA. We found that only Chlamydia infection was associated to positive ASA and multiplied by 4.7 the risk of positivity. By analyzing sperm, our study showed that leucospermia multiplied by 4.1 the risk of positive ASA and that the presence of S. aureus in sperm culture multiplied by 5.8 the risk of ASA positivity.
Empirically, we think that the more we are educated the less we adopt these risky behaviors. However, Clark P. and Kohler  in Malawi, Glynn et al.  in Benin, Gregson Zaddell and Chandiwana  in Zimbabwe and Hargreaves et al.  in South Africa found that the level of study high did not negatively influence the number of sexual partners. Also, Clark et al.  in Malawi and Mmbanga et al.  in Tanzania also did not find a positive relationship between level of study and condom use. These studies thus show that sexual behavior remains the same regardless of the level of education and therefore all men have the same degree of exposure to risky behavior that can lead to STDs, one of causes of ASA. This can explain why we did not find an association between level of education and ASA.
In our study, we found that businessmen and jobless were at high risk to have a positive ASA. Considering the fact that traders would usually have a short
Table 3. Socio-demographics characteristics and ASA serology.
Table 4. Clinical and paraclinical parameters and ASA serology.
sleep because often busy managing their business and they would often have a high income exposing them to risky sexual behaviors  , our results may be justified because short sleep and infections are associated with the presence of ACAS    . As for the jobless, who have almost nothing to do, they would generally have a long sleep, which is also associated with the presence of ASA  .
Although the duration of infertility and the type of infertility increase the risk of STDs by increasing risky sexual behavior    and STDs are responsible for the production of ASA by antigenic community with the spermatozoa or by destruction of the blood-testicular barrier   , we found no association between the duration of infertility in men and ACAS positivity. Unlike us, Tennakoon V  found the association.
The history of testicular trauma including testicular torsion and cure of hernia were found in our study being high risks for positive ASA. In humans, the conditions destroying the blood-testis barrier are an obvious risk factor for ACAS production, as the immune system comes into direct contact with the antigens on the surface of the spermatozoon    . Štula I et al  found in their study that ASA increased significantly after hernioraphy. They explained this by 2 mechanisms. The first mechanism is ischemia that occurs during manipulation of the spermatic cord   . The second mechanism is rupture of the blood-testis barrier resulting either from the direct lesion of the vas deferens or from its dilation   . The occurrence of ASA during violent trauma is explained by ischemia. Indeed, after the violent trauma at the level of the testicles, there is a decrease in the perfusion of the traumatized area with contusion and ischemia. It follows the rupture of the blood-testicular barrier and production of ACAS    .
In this study, we saw that past or current s sexual transmitted diseases multiply by 4.1 the risk of positive ASA but among STDs studied, only Chlamydia infection exposed at high risk of positive ASA. Microorganisms perform a range of fascinating adjustments to survive in the host. Among the various strategies used by microorganisms to overcome the host’s immune response, molecular mimicry allows microorganisms to manipulate host physiology and cellular functions to their advantage by mimicking host proteins and initiating autoimmunity. This phenomenon has been studied globally in the context of autoimmune diseases; however, its implications have also been reported in infertility    . Witkin SS as well as Siam EM and Hefzy EM also found a strong correlation between positive ASA serology and that against C. trachomatis   . Chronic infection of Chlamydia trachomatis has been shown to trigger an immune response in the male and female genital tract by antigenic community. Indeed, spermatozoa and chlamydia possess the hyperthermic shock protein Hsp60 which is associated with a humoral immune response. A humoral defense against C. trachomatis can also be directed against spermatozoa with production of ASA    .
We noted that leucospermia multiplied by 4.1 the risk of positive ASA and that the presence of S. aureus in sperm culture multiplied by 5.8 the risk of ASA positivity. In their study, Elizabeth Martinez-Prado et al.  found that the presence of leukocytes in sperm was significantly correlated with an increase in cytokines IL-6, IL-8 and TNF-a and anti-HSP-60 antibodies. protein present on spermatozoa. It is known   that the secretion of cytokines is one of the first signals of innate defense of the host to fight inflammation and infection of the genital tract by causing leukocyte chemotaxis at the site of inflammation and infection. The lymphocytes will thus come into contact with the spermatozoa and trigger the production of ASA  . In his study in Nigeria, Ekwere P.D found that in men with ASA, S. aureus was the most common germ found in culture  .
This study shows that factors that may lead to risky sexual behavior and physical or infectious trauma are important risk factors for ASA positivity. It is therefore necessary to search for them systematically during male infertility in order to guide the search for ASA.
Cite this paper
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