2012-02-06
Sexually transmitted diseases agents
All genetic information of every living body including infectious agents such as bacteria and viruses is encoded in the DNA molecule in the cell nucleus. Modern method of molecular biology, polymerase chain reaction (PCR), is used in the SORPO medical research center. The essence of PCR method: target fragments of the virus or human DNA in several hours are amplified millionfold, separated from other components, stained, identified and documented. It is accurate, quick and sensitive method.
Exceptional nature of PCR method:
•infectious agent is tested, but not body reaction to it;
•patient is not injured;
•disease could be identified in the very beginning;
•high sensitivity of the method: even small number of infectious agent allows identification of the disease;
•one specimen could be use for identification of multiple infectious agents.
SOPRO laboratory identifies causative agents of sexually transmitted diseases using modern molecular biology method, PCR (polymerase chain reaction). SORPO is the most experienced laboratory in Lithuania identifying causative agents of sexually transmitted diseases using accurate, quick and sensitive PCR method.
Whereas immune response to majority of these agents is very weak and their cultivation in microbiologic media requires special conditions molecular PCR method is very suitable for diagnostics.
Ten bacteria and viruses causing sexually transmitted diseases are identified in the SOPRO laboratory using PCR method. All these causative agents (except Trichomonas vaginalis) live in the host cells. Therefore the best test material is vaginal scraping in females and first void urine or urethral scraping in males. Specimen must contain epithelial cells that are used for the identification of STD causative agents. PCR method is extremely sensitive, and therefore tests (in other words, bacterial or virus DNA test) could be performed within a few days after infection. Follow-up PCR test is recommended to perform after 5-7 weeks after treatment completion. Using PCR test could also identify DNA of dead microorganism; therefore mucosa should regenerate after treatment.
According to World Health Organization actual number of sexually transmitted diseases is unknown. Nevertheless, it was estimated that annually 333 million of people get infected with sexually transmitted diseases. Approximately 20 different pathogenic bacteria and viruses cause sexually transmitted diseases. International healthcare programs targeted towards diagnostic, prevention and focalization of infections.
Causative agents of sexually transmitted diseases can seriously harm one's health. In females these infections could induce spontaneous abortions, extrauterine pregnancy, cause chronic abdominal pain, pelvic adhesions and inflammations, and postpartum uterine inflammations.
When pregnant woman get infected with the sexually transmitted infection, risk of spontaneous abortion occurs, newborns are underweighted, and they are at risk of lung and eye inflammations. Both in males and females untreated diseases could cause infertility, joint inflammation and specific inflammation of urethra manifesting by urethra tissue erosions and even running sores.
Chlamydia trachomatis
It is bacteria affects epithelium of reproductive tract, causes inflammations of urethra, epididymis and eye conjunctiva. Chlamydiosis is the most prevalent sexually transmitted disease, it causes up to 80% of all genital infections in adults. Humans are being infected during sexual intercourse.
Untreated this disease cause pelvic inflammations, extrauterine pregnancy, infertility; in males it causes prostatitis, sexual potency disorders and infertility. Newborn get an infection from infected mother at delivery, eye inflammation or pneumonia can develop.
This infection is often asymptomatic or its symptoms are very slight: poor mucous or purulent discharge from urethra, cervical channel or vagina, itching of genital organs and urethra, bleeding during intermenstrual period.
Ureaplasma urealyticum
Ureaplasma urealyticum is found in the human genital tract, it causes nonchlamydial and not gonococcal uretritis (inflammations of urethra) in males and cervicitis (inflammation of uterine cervix) in females. It could be prostatitis risk factor in males. It could also cause inflammation of bladder and urethers. In females infected with U. urealyticum discharge, whites, pain during urination and sexual intercourse, itching of external genitals could occur. U. urealyticum could be associated with arthritis; it could also cause spontaneous abortions. Therefore females should be checked for U. urealyticum infection before pregnancy. This infection could be asymptomatic, and it is found in 20-30% specimen obtained from sexually active women.
Mycoplasma hominis
This pathogenic bacterium resides in genital organs ant causes genital infections, usually in females. M. hominis also causes inflammations of genital organs and infections of non-genital organs in newborns, especially when immunity is lowered.
Mycoplasma genitalium
This pathogenic bacterium resides in genital organs. It causes various diseases: non-gonococcal urethritis (inflammation of urethra), prostatitis (inflammation of prostate), pregnancy and fetus diseases, infertility in males and females. Quite frequently mycoplasms are found in males and females with gonorrhea or history of gonorrhea, because gonococci and trichomonads provide favorable conditions for mycoplasma development. Mycoplasms usually cause chronic diseases. In acute period purulent or abundant discharge from genital organs occurs, as well as itching and burning sensation in genital organs. In some cases enlarged inguinal lymphatic nodes are found. In males M. genitalium is risk factor for prostatitis.
Neisseria gonorrhoeae
Gonorrhea is a specific urethritis. It is sexually transmitted infection; however, it is possible to catch this infection through household goods (beddings, towels, underwear) contaminated with gonococci. Newborn could catch gonorrhea during delivery when mother is infected. Infection affects tissues of urethra, and therefore purulent wounds occur. It is more discernible in males then in females. Symptoms of infection are usually minimal; therefore early and accurate diagnosis is crucial for successful treatment.
Symptoms of the infection: abundant vaginal discharge, itching during urination, pain in the lower abdomen. Males feels burning during urination, yellowish discharge from the penis occur, disease could be complicated with epididymitis which, if untreated, could cause infertility.
Pharyngeal form of gonorrhea causes laryngeal redness, swelling and pain. Gonorrhoic arthritis affects joints; joint swelling, redness, pain at movements and fever occur.
Common methods of N. gonrrhoeae identification are of low specificity and sensitivity. SORPO laboratory uses quick and accurate PCR method for N. gonorrhoeae identification.
Gardelia vaginalis
Anaerobic bacteria occur in vagina when imbalance natural microflora occurs and bacterial vaginosis develops. Enzymes of reproducing pathogenic bacteria damage natural protective barrier – mucus in the cervical channel. Then infection can spread in the uterine cavity, fallopian tubes, abdominal cavity and cause inflammation of genital organs and pelvis (endometrium, ovaries and fallopian tubes, acute peritonitis).
Trichomonas vaginalis
It damages human genitals. In females T. vaginalis causes inflammations of urethra, vagina and cervix, and in males – inflammations of urethra, prostate and testicles. No permanent immunity against T. vaginalis form, and therefore there could be relapse of the disease.
Symptoms of trichomoniasis: frothy, yellow-green, foul-smelling vaginal discharge, redness of the external genitals, itching, frequent desire to urinate. Males usually have asymptomatic trichomoniasis. Asymptomatic trichomoniasis is observed in 25% of infected women.
Candida spp., Candida albicans
Mycotic infection causes candidamycosis, specific inflammation of genital organs. Causes of candidamycosis: 1) exogenic, when fungus invade body from the external source; 2) endogenic, when body resistance decreases; 3) use of antibiotics, when imbalance between normal pathogenic microorganisms occurs.
Symptoms of the disease: females feel vaginal burning and itching, there is abundant discharge, like cottage cheese; pain during urination, redness and swelling of external genitals occurs. Pustules and small bleeding wounds could occur on the surface of external genital organs. In males candidamyxosis manifests as balanitis and balanopostitis.
To perform tests using PCR method vaginal scraping in females and first void urine or urethral scraping in males are obtained.
Test duration – 2 days. Tests are performed on a daily basis.
Herpes simplex virus (HSV 1/2)
There are two types of Herpes simplex virus: type 1 HSV causes Herpes simplex of lips, oral mucosa and skin; type 2 HSV causes genital herpes. It is extremely prevalent virus: antibodies to HSV-1 have 90%, ant to HSV-2 – about 20% of all adults. Humans usually catch HSV-1 in their childhood. Source of virus is patient with active or asymptomatic disease. HSV virus is an airborne infection or it could be transmitted through direct contact (kissing, during sexual intercourse, at delivery). Herpes viruses invade the body trough damaged mucosa of oral cavity, eye, and genital organs or through undamaged skin.
Onset of the disease could be asymptomatic or sporadic skin pustules occur. Initially skin (mucosa) redness and swelling occur; patient could feel itching, burning, tension and pain. Later papules filled with clear fluid, and painful ulcers develop following their rupture. Enlargement of lymphatic nodes and fever may occur. Acute period may be accompanied with common cold-like symptoms: fever, headache, back and muscle pain. Virus reproduces; it causes host’s immune reaction and invades peripheral sensory nerves and subsequently invades sensory ganglia of the central nervous system (CNS). Virus becomes inactive but remains in the body. Latent and non-reproducing viruses remain in the ganglia of spinal cord and may persist there for a relatively long time. When favorable conditions occur (common cold, overexposure of ultraviolet rays, hormonal disorders, stress or depressed mood), Herpes virus reactivates and invades sensory nerves again causing their damage and damaging surfaces they innervate. Symptoms of the disease usually are less pronounced comparing with initial disease, and this depends on individual immunity. Sometimes virus invades brain meninges or neurons and causes meningitis or encephalitis.
When HSV test using molecular PCR method is performed in SORPO laboratory it include both type 1 and type 2 HSV viruses; however, virus types are not identified. When virus is found in the material investigated, the result is being identified as “positive” (or “virus found”); when virus is not found, result is “negative”.
To perform tests using PCR method vaginal scraping in females and first void urine or urethral scraping in males are obtained.
Test duration – 2 days. Tests are performed on a daily basis.