The positive rate with the common sexually transmitted agents and some relevant factors of the patients with urethral/vaginal discharge syndrome

52 DERMATOLOGY No. 29 (September 2019)
SCIENTIFIC RESEARCH
THE POSITIVE RATE WITH THE COMMON SEXUALLY 
TRANSMITTED AGENTS AND SOME RELEVANT FACTORS OF THE 
PATIENTS WITH URETHRAL/VAGINAL DISCHARGE SYNDROME
Hoang Thi Hoai *, Pham Thi Lan *,**, Dinh Huu Nghi *,**, Le Van Hung *,**, Phuong Quynh Hoa**, 
Le Huyen My**
ABSTRACT
Objective: to investigate the positive rate with 11 sexually transmitted agents and some relevant 
factors of the patients with urethral/ vaginal discharge syndrome examined at National Hospital of 
Dermatology and Venereology from August 2018 to July 2019. 
Subjects and method: 120 patients with clinically urethral/vaginal discharge syndrome were 
tested to find 11 sexually transmitted agents using molecular hybridization test. 
Results: The ratio of male/female was 2.7/1. The most common age of suffering from disease was 
20-29 years old. The positive rate with at least one agent was 33.3%. Chlamydia trachomatis (CT) was the 
most common agent, accounting for 13.3%. Other agents had the positive rates as follows Neissseria 
gonorrhoeae (NG) 6.7%; Mycoplasma gentalium (MG) 9.2%; Ureaplasma parvum/Ureaplasma urealyticum 
(UU/UP) 7.5%; Mycoplasma hominis (MH) 1.7%; Herpes simplex virus type 1/2 (HSV 1/2) 1.7%; Human 
papillomavirus type 6/11 (HPV 6/11) 8.3%; there were no cases positive for Trichomonas vaginalis (TV). 
The coinfection rate among the cases with positive results was 13/40 (32.5%). In which, the coinfection 
rates of MG-UU/UP 36.4%; CT-NG 25%; CT-UU/ UP 18.7%; MG-CT 18.2%. The positive rate with the agents 
was higher in the group of patients with cloudy discharge and subjective symptom.
Conclusion: The urethral and vaginal discharge syndrome was often common in the age with strong 
sexual activity. The prevalence of sexually transmitted agents in this group of patients was relatively 
high, in which a lot of cases were co-infected more than one agent. There was a relation between the 
positive rate with the agents and the discharge properties and subjective symptom of patients.
Key words: Urethral/vaginal discharge syndrome, 11 sexually transmitted agents 
1. INTRODUCTION
According to the estimates of the World Health 
Organization, every year in the world there are up 
to 370 million new cases of sexually transmitted 
infections (STIs) and there are more than 1,000,000 
people infected each day, in which up to 85% of 
patients have no symptoms or atypical clinical 
manifestations; therefore the early diagnosis is 
missed [1]. The improper or untimely treatment 
Scientific Reviewer: Assoc. Prof. PhD. Le Huu Doanh
* Hanoi Medical University
** National Hospital of Dermatology and Venerology
53No. 29 (September 2019) DERMATOLOGY 
SCIENTIFIC RESEARCH
increases the risk of complications for the patients 
and the risk of drug resistance. Thus, a proper 
diagnosis is very necessary before starting treatment.
Currently, more than 30 bacteria, viruses and 
parasites, which can cause sexually transmitted 
diseases, have been identified, such as Chlamydia 
trachomatis, Neissseria gonorrhoeae, Treponema 
pallidum, Mycoplasma, Herpes simpex virus, 
Ureaplasma, Human papillomavirus, Trichomonas 
vaginalis, Among them, sexually transmitted 
diseases (STDs) also had a high rate of coinfection; 
in particular, 30.4% of patients infected with 
Mycoplasma genitalium were co-infected with 
gonorrhea and 25% were co-infected with 
Chlamydia trachomatis [2]; 3.4% of patients 
infected with Mycoplasma hominis were co-
infected with Ureaplasma urealyticum [3]. 
Depending on the causative agents, there 
are many different diagnostic methods such as 
Gram staining, cultivation, serological reaction, 
nucleic acid amplification test, etc... The test to 
find 11 sexually transmitted agents by molecular 
hybridization method based on the nucleic acid 
amplification reaction has high sensitivity and 
specificity, and it is quick to have the testing 
results. This test has been approved for diagnosis 
of sexually transmitted diseases by Centers for 
Disease Control and Prevention (CDC) of the 
United States [4]. In the world, there have been 
the studies on this technology in determining 
the prevalence of STDs; however, in Vietnam 
there is a lack of data and studies on this method. 
Therefore, we conducted a study with the aim 
of surveying the positive rate with 11 sexually 
transmitted agents and some relevant factors 
for the patients with urethral/vaginal discharge 
syndrome examined at National Hospital of 
Dermatology and Venereology.
2. SUBJECTS AND METHOD 
2.1. Research subjects 
The research subjects were the patients 
with urethral/ vaginal discharge syndrome 
examined at National Hospital of Dermatology 
and Venereology from August 2018 to July 2019.
Criteria for selecting patients: The patients 
had urethral discharge syndrome or vaginal 
discharge syndrome. 
- Symptoms of urethral discharge syndrome:
+ ... n method.
- Age ≥ 18.
2.2. Research method and materials 
2.2.1. Research design: Descriptive cross-sectional 
study. 
2.2.2. Steps to conduct the study 
- Patients were required to report their 
medical history, risk factors.
- Using cotton swabs to get the specimens 
from urethra (for men) or cervix, vagina (for 
women).
54 DERMATOLOGY No. 29 (September 2019)
SCIENTIFIC RESEARCH
- Conduct testing technologies:
+ DNA extraction
+ PCR running 
+ Conduct molecular hybridization by using 
GenoFlow STD Array Test Kit and Flow Through 
Hybridization System of DiagCor.
+ Read the results by using DiagCor’s image 
capture system.
2.2.3. Data processing: The data were entered 
and processed by SPSS 19.0 statistical software. 
Quantitative variables were expressed as means 
and standard deviation, qualitative variables were 
expressed as percentages (%). Chi-square test or 
Fisher’s Exact test was used to compare the ratios.
3. RESEARCH RESULTS 
3.1. General characteristics of the patients
Characteristics Number of patients Percentages (%)
Gender 
Male 88 73.3
Female 32 26.7
Age 
≤ 19 1 0.8
20 - 29 58 48.3
30 - 39 39 32.5
40 - 49 13 10.8
≥ 50 9 7.5
The percentage of male was 73.3%; the percentage of female was 26.7%. The median age of the 
patients was 30. The youngest patient was 19 and the oldest was 59. The most common age of suffering 
from disease was 20-29 and 30-39, accounting for 48.3% and 32.5%, respectively.
3.2. The positive rate with 11 sexually transmitted agents 
No. Causative agents Number of patients (n = 120) Percentages %
1 At least 1 causative agent 40 33.3
1 CT 16 13.3
2 NG 8 6.7
3 MG 11 9.2
4 UU/UP 9 7.5
5 TV 0 0
6 MH 2 1.7
7 HPV 6/11 10 8.3
8 HSV 1/2 2 1.7
55No. 29 (September 2019) DERMATOLOGY 
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No. Causative agents Number of patients (n = 120) Percentages %
The co-infection rate of the causative agents 
9 Co-infection with at least 2 causative agents 13/40 32.5
11 Co-infection with MG-CT 2/11 18.2
12 Co-infection with CT-NG 4/16 25
13 Co-infection with CT-UU/UP 3/16 18.8
14 Co-infection with MG-UU/UP 4/11 36.4
Among 120 patients participating in the study, 40 patients had the positive test results with at least 
one causative agent, accounting for 33.3%. In particular, CT was the most common agent, accounting 
for 13.3%; The percentages of other factors were respectively MG (9.2%), NG (6.7%), UU/ UP (7.5%), MH 
(1.7%), HSV 1/2 (1.7%), HPV 6/11 (8.3%); No patients were infected with TV. 
In terms of the co-infection rate among agents, among 40 patients with the positive results, there 
were 13 patients co-infected with more than one agent (32.5%). Among 11 patients who were positive 
for MG, 4 cases were co-infected with UU/ UP (36.4%) and 2 cases were co-infected with CT (18.2%). In 
16 cases positive for CT, 4 cases were co-infected with NG (25%) and 3 cases were co-infected with UU/ 
UP (18.8%).
3.3. Gender and positive rate of the causative agents 
No. Causative agents 
Urethral discharge 
(n = 88)
Vaginal discharge 
(n = 32) p
n % n %
1 At least 1 causative agent 31 35.2 9 28.1 0.465
2 CT 14 15.9 2 6.2 0.231
3 NG 7 8 1 3.1 0.68
4 MG 8 9.1 3 9.4 1
5 UU/UP 7 8 2 6.2 1
6 TV 0 0 0 0
7 MH 0 0 2 6.2 0.069
8 HPV 6/11 5 5.7 5 15.6 0.129
9 HSV 1/2 2 2.3 0 0 1
Among the 120 patients, 88 patients had urethral discharge syndrome (male patients) and 32 
patients had vaginal discharge syndrome (female patients). The prevalence of at least 1 causative agent 
in the male group was 31/88 (35.2%), in the female group was 9/32 (28.1%). The common causative agent 
in the male group was CT (15.9%), and in the female group was HPV 6/11 (15.6%). The difference in the 
prevalences of agents in the two groups was not statistically significant with p > 0.05 (Fisher’s Exact test).
56 DERMATOLOGY No. 29 (September 2019)
SCIENTIFIC RESEARCH
3.4. The discharge properties and positive rate of the causative agents 
No. Causative agents 
Cloudy (n = 16) Clear (n = 104)
p
n % n %
1 At least 1 causative agent 11 68.8 29 27.9 0.001
2 CT 5 31.2 11 10.6 0.039
3 NG 7 43.8 1 1 0.000
4 MG 2 12.5 9 8.7 0.64
5 UU/UP 1 6.2 8 7.7 1
6 TV 0 0 0 0
7 MH 2 12.5 0 0 0.017
Among 120 patients, only 16 patients had cloudy discharge, 104 patients had clear discharge. 
However, in the group with cloudy discharge, up to 11/16 patients (68.8%) had positive results with at 
least 1 causative agent, much higher than the group with clear discharge (27.9%). This difference was 
statistically significant with p < 0.05 (Chi-square test). 
Among the patients with cloudy discharge, the prevalence of NG is the highest (43.8%). The 
prevalence of other agents were CT (31.2%), MG (12.5%), MH (12.5%), UU/ UP (6.2%) respectively. The 
prevalence of CT, NG and MH agents in the group with cloudy discharge was higher than that in the 
group with clear discharge; the difference was statistically significant with p < 0.05 (Fisher’s Exact test). 
3.5. The subjective symptom and positive rate of the causative agents 
No. Causative agents
Yes (n = 31) No (n = 89)
p
n % n %
1 At least 1 causative agent 20 64.5 20 22.5 0.000
2 CT 11 35.5 5 5.6 0.000
3 NG 7 22.6 1 1.1 0.000
4 MG 6 19.4 5 5.6 0.033
5 UU/UP 5 16.2 4 4.5 0.049
6 TV 0 0 0 0
7 MH 0 0 2 2.2 1
8 HPV 6/11 4 12.9 6 6.7 0.28
9 HSV 1/2 1 3.2 1 1.1 0.452
Among 120 patients, there were 31 patients with subjective symptom and 89 patients without 
subjective symptom. In the group with subjective symptom, up to 20 patients (64.5%) had the test 
results positive for at least 1 causative agent. This rate in the group without subjective symptom was 
only 20/89 (22.5%). This difference was statistically significant with p < 0.05 (Chi-square test). 
Among the patients with subjective symptom, CT was the most common agent, accounting for 35.5%. 
Other causative agents also had high prevalence such as NG (22.6%), MG (19.4%), UU/ UP (16.2%). The 
57No. 29 (September 2019) DERMATOLOGY 
SCIENTIFIC RESEARCH
prevalence of these agents was much higher than 
that of the group without subjective symptom, 
this difference was statistically significant with p 
< 0.05 (Fisher’s Exact test).
4. DISCUSSION 
Among 120 studied patients, men accounted 
for the majority (73.3%), nearly 3 times as high as 
women. The average age suffering from disease 
of both genders was 32.1 ± 9.2, in which the most 
common age group was from 20 to 29 years old; 
this was entirely appropriate because this age 
group in both men and women had strong sexual 
activity. 
In terms of prevalence of sexually 
transmitted agents, we tested 120 specimens of 
discharge from urethra (for men) and vagina (for 
women), the results showed that there were 40 
cases positive for at least one causative agent, 
accounting for 33.3%. Among them, Chlamydia 
trachomatis was the most common agent with the 
positive rate of 16/120 (13.3%); other causative 
agents had positive rates as follows: Mycoplasma 
gentalium 9.2%; Neissseria gonorrhoeae 6.7%; 
Ureaplasma parvum/Ureaplasma urealyticum 
7.5%; Mycoplasma hominis 1.7%; HSV 1/2 1.7%; 
HPV 6/11 8.3%; no cases were positive for 
Trichomonas vaginalis. This result was different 
from the study of Rubina Ghani et al (2014) on 
60 semen specimens of male patients without 
clinical manifestations in Pakistan, which had 
up to 20.83% of specimens containing MH; 
10.41% containing UU/UP; 6.25% containing CT 
and 4.16% containing NG; 2.08 containing TV; 
2.08% containing HPV 6/11 [5]. Another study 
by Binderya G. (2014) in Mongolia on 1473 
specimens from urethra and cervix (using cotton 
swabs) showed 19.1% positive for NG; 11.4% 
positive for CT; 8.6% positive for TV; 7.4% positive 
for MG; and up to 43.9% containing UU/UP, MH; 
0.6% positive for HSV 1/2; and up to 35.9% of 
women were positive for HPV [6]. The difference 
in positive rates of the agents commonly causing 
sexual transmitted diseases can be explained by 
the differences in research locations, subjects 
and specimens. In different regions, there have 
been different morbidity patterns of sexually 
transmitted diseases.
The results in the Table 3.2 showed that out 
of 40 cases with positive test results, 13 cases 
(32.5%) were co-infected with more than one 
causative agent. This result was lower than the 
study of Judith Lucena Nemirosky et al. (2012) 
which stated that the co-infection rate of causative 
agents was up to 50.8% (685/1346) [7]. In our 
study, Mycoplasma gentalium and Ureaplasma 
parvum/Ureaplasma urealyticum had the highest 
co-infection rate, accounting for 36.4%. Other 
causative agents also had high co-infection rates 
such as Chlamydia trachomatis and Neissseria 
gonorrhoeae (25%), Chlamydia trachomatis and 
Ureaplasma parvum/Ureaplasma urealyticum 
(18.75%), Mycoplasma gentalium and Chlamydia 
trachomatis (18.2%), Mycoplasma gentalium and 
Neissseria gonorrhoeae (9.1%). When compared 
to other studies around the world, we found 
that there were differences in research results. 
According to the study by Mobley et al (2012), 
among the cases of MG infection, 30.4% were co-
infected with NG and 25% were co-infected with 
CT [2]. Another study by Kahn et al (2005) showed 
that the rate of co-infection between CT and NG 
58 DERMATOLOGY No. 29 (September 2019)
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was 54% in women (n = 33619) and 51% in men 
(n = 98296) [8], this result was much higher than 
our study. This difference can be explained by the 
fact that our sample size was not large enough; at 
the same time, there were differences in research 
locations, subjects and methods.
The results in the Table 3.3 showed that the 
prevalence of at least one causative agent in the 
group of male patients was 31/88 (35.2%), in the 
group of female patients was 9/32 (28.1%). The 
common causative agent in male patients was CT 
(15.9%), in female patients was HPV 6/11 (15.6%). 
There was no difference in the positive rates of 
causative agents between the two groups of 
male and female patients. This result was similar 
to a investigation about the prevalence of NG and 
CT in the population aged 14-49 in Morocco from 
1995 to 2005 [9].
Regarding the properties of urethral/
vaginal discharge, among 120 patients, only 
16 cases had cloudy discharge, the remaining 
104 patients had clear discharge. The most 
common causative agent in the group of patients 
with cloudy discharge was NG (43.8%) and CT 
(31.2%), and in the group of patients with clear 
discharge was CT (10.6%). Among the patients 
with cloudy discharge, up to 11/16 patients 
(68.8%) had positivity for at least 1 causative 
agent, much higher than the group of patients 
with clear discharge (27.9%). This difference was 
statistically significant with p < 0.05 (Chi-square 
test). The prevalence of CT, NG and MH agents in 
the group of patients with cloudy discharge was 
also higher than that in the group of patients with 
clear discharge. This difference was statistically 
significant with p <0.05 (Fisher’s Exact test). This 
showed a relevance between the discharge 
properties of patients and the prevalence of 
sexually transmitted agents.
Apart from clinical symptoms, many patients 
have other subjective symptoms such as genital 
itching and burning, dysuria, etc... The results in the 
Table 3.5 showed that among 120 patients, there 
were 31 patients with subjective symptoms and 
89 patients without those symptoms. The most 
common agent causing subjective symptoms 
for patients was CT (33.5%) and NG (22.6%). The 
rate was much higher than the group without 
subjective symptoms. This expressed a relevance 
between the patients’ subjective symptoms and 
the prevalence of sexually transmitted agents.
5. CONCLUSION
The study of 120 patients with urithral/
vaginal discharge syndrome examined at National 
Hospital of Dermatology and Venereology from 
August 2018 to July 2019, we had the following 
conclusions: 
Men were easier to suffer from STDs than 
women, the prevalence of men was nearly 3 times 
as high as that of women. The most common age 
of suffering from STDs was from 20 to 29 years old.
The positive rate with at least one sexually 
transmitted agent of the studied group was 33.3%, 
in which the most common agent was Chlamydia 
trachomatis. The co-infection rate among the 
causative agents was also relatively high.
There was a relation between the positive 
rate with the causative agents and the properties 
of urethral/ vaginal discharge and the subjective 
symptoms of the patients.
59No. 29 (September 2019) DERMATOLOGY 
SCIENTIFIC RESEARCH
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