Microbial Diseases Of The Urinary and Reproductive Systems |
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Most diseases of the reproductive system are sexually transmitted diseases (STDs).
Most STDs can be prevented by the use of condoms and are treated with antibiotics.
Gonorrhea (the clap) is caused by the gram-negative diplococcus Neisseria gonorrhoeae.
Gonorrhea is the most common reportable communicable disease in the U.S.
Attaches to mucosal cells of the oral-pharyngeal area, genitals, eyes, and rectum by fimbrae.
Females may be asymptomatic until the infection spreads to the uterus and uterine tubes. Symptoms in males are painful urination and pus discharge.
Complications in males are blockage of the urethra and sterility. Complications in females include blockage of the uterine tubes, sterility, pelvic inflammatory disease. Complications affecting both genders are endocarditis, meningitis, and arthritis.
Opthamlia neonatorum is an eye infection acquired by infants during passage through the birth canal of an infected mother.
Diagnosis is by culture and identification using a FA procedure or DNA probe.
Treatment is penicillin although penicillinase producing strains exist. Ceftriaxone is the drug of choice. Spectinomycin or ciprofloxacin may be used.
Any inflammation of the urethra not caused by Neisseria gonorrhoeae.
Chlamydia trachomatis is the most common cause of NGU and probably the most common sexually transmitted pathogen.
Symptoms are often mild or lacking, although salpingitis (uterine tube inflammation) and sterility may occur.
Can be transmitted to infants’ eyes at birth, causing conjunctivitis and pneumonia.
Other causes of NGU include Ureaplasma urealyticum and Mycoplasma hominis.
Treatment of NGU is with tetracycline (doxycycline) or macrolides (azithromycin).
Extensive bacterial infection of the female pelvic organs, especially of the reproductive system, is called pelvic inflammatory disease (PID). Salpingitis, or infection of the uterine tubes, is the most serious form of PID.
PID is caused by N. gonorrhoeae, Chlamydia trachomatis, and other bacteria that gain access to the uterine tubes.
Salpingitis
Caused by the gram-negative spirochete Treponema pallidum, which has never been cultured in vitro. Cultures are grown in rabbits or cell cultures.
Transmitted by direct contact although T. pallidum can penetrate mucous membranes and breaks in the skin.
The primary lesion is a small, hard based chancre at the site of the infection. The bacteria invade the blood and lymphatic system and the chancre spontaneously heals. The chancre is painless and may not be noticed by the patient - it may form on the cervix or in the urethra of males.
The secondary stage is marked by a widely disseminated rash (containing spirochetes) on skin and mucous membranes. Loss of hair, malaise, and fever may also be observed, however the secondary stage may be so mild that it isn't noticed by the patient.
There is a latent period after the secondary lesions heal. After 2-4 years of latency the disease is not normally transmissible except transplacentally.
At least 10 years after the secondary lesions heal tertiary lesions called gummas can appear on many organs. Cardiovascular syphilis will cause weakening of the aorta and neurosyphilis may many symptoms, from dementia to loss of voluntary motor movement.
Congenital syphilis, resulting from the organism crossing the placenta during the latent period, can cause neurological damage in the newborn.
Diagnosis is by darkfield microscopy, nontreponemal serological tests (VDRL - Venereal Disease Research Laboratory - or RPR - rapid plasma reagin test), and treponemal serological tests (FTA-ABS or fluorescent treponemal antibody absorption test).
Direct observation is used int the primary stage when organisms are present and the body hasn't made antibodies against them.
In the secondary stage serological tests are positive, but the antibodies are directed against lipids the body makes as an indirect response to initial infection. These are the reagin-type antibodies detected in the VDRL and RPR tests.
The treponemal serological tests are used in late stage syphilis and detect anti-treponemal antibodies.
Treatment is penicillin. Treponema is very sensitive to penicillin but the course of treatment needs to run longer than that used to treat other organisms.
Caused by Chlamydia trachomatis and is primarily a disease of tropical and subtropical areas.
The initial lesion on the genitals and heals without scarring.
The bacteria spread via the lymph and cause enlargement of the lymph nodes, obstruction of lymph vessels, and swelling of the external genitals.
Organisms are isolated and identified from pus taken from lymph vessels.
Treatment is tetracycline or erythromycin.
Chancroid, a swollen painful ulcer on the mucous membranes of the genitals or mouth, is caused by the gram-negative rod Haemophilus ducreyi.
Treatment is tetracycline or trimethoprim-sulfamethoxazole.
Vaginosis (Gardnerella vaginitis) is an infection without inflammation caused by Gardnerella vaginalis.
Gardnerella vaginalis is an opportunistic pathogen, the disease occurs when pH is 5 to 6. It is characterized by a thin, gray-white frothy discharge with a fishy odor and the presence of clue cells.
Clue Cells
Treatment of Gardnerella vaginitis is metronidazole.
Other causes of vaginitis include Candida albicans and Trichomonas vaginalis.