Type of test

Microscopic examination

 Normal findings

 No evidence of STD

Test explanation and related physiology

In the United States, common STDs include Chlamydia, genital herpes (herpes simplex virus), human papilloma virus (HPV), syphilis, human immunodeficiency virus (HIV), trichomonas, and gonorrhea (Table 1). In this test discussion, we will concentrate on Trichomonas vaginalis and Neisseria gonorrhoeae, as all others are discussed elsewhere in this reference book. Early identification of STDs enables sexual partners to obtain treatment as soon as possible and thereby reduce the risk of disease spread.

Table1. Sexually transmitted diseases (STDs) and methods of diagnosis

Furthermore, prompt treatment reduces the risk of infertility in women. If the STD result is positive, sexual partners should be evaluated and treated. Performing STD testing is also part of the prenatal workup.

T. vaginalis can cause urethritis, vaginitis, endometritis, pelvic inflammatory disease, pharyngitis, proctitis, epididymitis, prostatitis, and salpingitis. Children born of infected mothers may develop conjunctivitis, pneumonia, neonatal blindness, or neonatal neurologic injury and may even die. The most commonly used method for detection is microscopic examination of a wet-mount preparation of vaginal secretions. However, this method has only a 35% to 80% sensitivity. Culture of urethral or vaginal secretions also suffers from relatively low sensitivity. Culture is technically challenging and takes 5 to 7 days to complete. Molecular methods of testing urethral and vaginal secretions offer high sensitivity and specificity for detection of trichomoniasis.

Gonorrhea is caused by the bacterium N. gonorrhoeae. Many infections in women are asymptomatic. This organism causes genitourinary infections in women. Because infection in men is commonly associated with symptoms, screening of asymptomatic patients is not indicated. However, in light of the risk for asymptomatic infection in women, screening is recommended for women at high risk for infection. High-risk women include women with previous gonorrhea or other STD, inconsistent condom use, and new or multiple sex partners and women in certain demographic groups such as those in communities with high STD prevalence.

Culture was previously considered to be the gold standard test for diagnosis of N. gonorrhoeae infection. Yet successful culture methods are difficult. Molecular laboratory methods per formed on urethral, rectal, vaginal, or oropharyngeal secretions provide superior sensitivity and specificity.

To obtain an appropriate specimen for women, swabs (that are sometimes specific to the particular laboratory) are obtained from the endocervix, vagina, urethra, urine, or a Pap ThinPrep. For men, a swab of the urethra or a urine specimen is used for testing. Rectal and throat swabs are performed in persons who have engaged in anal and oral intercourse. Because rectal gonorrhea accompanies genital gonorrhea in a high percentage of women, rectal cultures are recommended in all women with suspected gonorrhea. If the STD culture result is positive, treatment during pregnancy can prevent possible fetal complications (e.g., ophthalmia neonatorum) and maternal complications. Rectal and orogastric specimens should be performed on the neonates of infected mothers.

STD cultures and smears are obtained by a physician or nurse in several minutes during a pelvic examination. Very little dis comfort is associated with these procedures.

 Interfering factors

 • N. gonorrhoeae is very sensitive to lubricants and disinfectants.

• Menses may alter test results.

• In women, douching within 24 hours before a cervical culture makes fewer organisms available for culture.

• In men, voiding within 1 hour before a urethral culture washes secretions out of the urethra.

• Fecal material may contaminate an anal culture.

Procedure and patient care

 Before

* Explain the purpose and procedure to the patient. Use a matter-of-fact, nonjudgmental approach.

* Tell the patient that no fasting or sedation is required.

During

Cervical culture

 • The female patient is told to refrain from douching and tub bathing before the cervical culture.

 • The patient is placed in the lithotomy position, and a vaginal speculum is inserted to expose the cervix (see Figure 1).

 • Excess cervical mucus is removed with a cotton ball.

• A sterile cotton-tipped swab is inserted into the endo cervical canal and moved from side to side to obtain the specimen.

 • The swab is placed in sterile saline or a transporting fluid obtained from the laboratory. The specimen should be plated as soon as possible.

Fig1. Papanicolaou (Pap) smear. A, The vaginal speculum is shown in position to allow direct visualization of the cervix. B, The cervix is scraped with the bifid end of a wooden spatula.

Anal canal culture

 • An anal culture of the female or male patient is taken by inserting a sterile, cotton-tipped swab approximately 1 inch into the anal canal (Figure 2).

• If stool contaminates the swab, a repeat swab is taken.

Fig2. Rectal culture of the female. Method for obtaining an anorectal culture for sexually transmitted diseases in a female patient.

Oropharyngeal culture

• This culture should be obtained in male and female patients who have engaged in oral intercourse.

• A throat culture is best obtained by depressing the patient’s tongue with a wooden tongue blade and touching the posterior wall of the throat with a sterile cotton-tipped swab.

Urethral culture

 • The urethral specimen should be obtained from the male patient before he voids. Voiding within 1 hour before col lection washes secretions out of the urethra, making fewer organisms available for culture. The best time to obtain the specimen is before the first morning micturition.

• A culture is taken by inserting a sterile swab gently into the anterior urethra (Figure3).

• It is advisable to place the male patient in the supine position to prevent falling if vasovagal syncope occurs during introduction of the cotton swab or wire loop into the urethra.

• The patient is observed for hypotension, bradycardia, pallor, sweating, nausea, and weakness.

• In a male patient, prostatic massage may increase the chances of obtaining positive cultures.

Fig3. Urethral culture of the male. Method for obtaining a urethral culture for sexually transmitted diseases in a male patient.

 Urine culture

• Obtain the first catch voided specimen in the female patient. (Urine cultures for STD are not helpful in male patients.)

After

 • Place the swabs for gonorrhea in a Thayer-Martin medium and roll them from side to side.

 • Label and send the culture bottle to the microbiology laboratory as soon as possible.

• Handle all specimens as though they were capable of trans mitting disease.

 • Do not refrigerate the specimen.

• Mark the laboratory slip with the collection time, date, source of specimen, patient’s age, current antibiotic therapy, and clinical diagnosis.

* Advise the patient to avoid intercourse and all sexual contact until test results are available.

* If the culture results are positive, tell the patient to receive treatment and to have sexual partners evaluated.

• Note that repeat cultures should be taken after completion of treatment to evaluate therapy.

 Abnormal findings

 STDs

اخر الاخبار

اخبار العتبة العباسية المقدسة

قسم الشؤون الطبية يُنهي استعداداته لإحياء شهادة الإمام الحسن العسكري (عليه السلام) في سامراء

بالصور.. المؤمنون يتوافدون إلى سامراء لإحياء ذكرى شهادة الإمام الحسن العسكري (عليه السلام)

العتبة العباسية المقدسة تنشر لافتات العزاء بذكرى شهادة الإمام الحسن العسكري (عليه السلام)

الممثل الخاص للأمم المتحدة في العراق يشيد بتجربة مجموعة العميد ويصفها بالأنموذج المتكامل

المزيد

الآخبار الصحية

لا تبحث عن الدواء.. هذه الأطعمة كفيلة بإيقاف ألم الرأس

لا تترك زجاجة الماء في السيارة.. احذر شربها

عادة يومية.. كيف يؤثر تصفيف الشعر على جهازك التنفسي؟

احذر هذه الأطعمة.. تسرع الشيخوخة وتفقد بشرتك شبابها

المزيد

الآخبار التكنلوجية

الأوكتان وتأثيره: نصائح لحماية محرك سيارتك بكفاءة وأمان

حرب شهر سبتمبر تشتعل.. ماذا في جعبة أبل وسامسونغ؟

واتساب يطلق ميزة لتعديل الرسائل بالذكاء الاصطناعي

على الكوكب الأحمر.. ناسا تعثر على "قبعة الساحرة"

المزيد

مواضيع ذات صلة

sickle cell screen (Sickledex, Hemoglobin [Hgb] S test)

serotonin (5-hydroxytryptamine, 5-HT) and chromogranin A

Hypokalemia

Hypernatremia

Hyponatremia

semen analysis (Sperm count, Sperm examination)

rubella antibody test (German measles test)

ribosome P antibodies (Ribosomal P Ab, Anti–ribosome P antibodies)

Water Balance

Albuminuria

Proteinuria

rheumatoid factor (RF)