VENEREAL DISEASES
Venereal diseases are
transmitted by sexual contact. Syphilis is caused by a spiral-shaped bacterium,
a spirochete. This disease is especially dangerous because after initial infection of the genitals or mucous membranes it may become quiescent for years and then activate and cause damage to the nervous system or cardiovascular system. The chancre, a painless ulcer, is the most common initial lesion. Syphilis may be diagnosed by blood tests. Treatment with antibiotics is very effective. Gonorrhea is a common bacterial disease characterized by inflammation of the urethra. In females, inflammation of the fallopian tubes may result in abdominal pain, fever, and sterility. Gonorrhea is diagnosed by bacterial cultures. Antibiotic therapy is extremely effective. Sexually
transmitted urethritis may also be caused by other microorganisms, including Chlamydia and Ureaplasma. Chlamydia is a very important cause of sexually transmitted disease; it has been implicated in inflammatory diseases of the reproductive organs in females, resulting in infertility. When transmitted to infants, Chlamydia may cause eye infection and pneumonia. Herpes simplex type 2 is a virus that causes painful involvement of the genital area and can also cause severe
infections in the newborn.
OTHER INFECTIONS
The brain and spinal cord may be directly involved in infection. Viral encephalitis damages the brain, and poliomyelitis is an infection of the spinal cord. The lining of the nervous system may be affected by meningitis due to bacteria, viruses, or fungi. Bacterial infection of the urinary tract is common, especially in adult women. Antimicrobial therapy is effective unless there is a structural abnormality present. Infections of bone (osteomyelitis) and of joints (septic arthritis) may result in deformity and disability. Infective endocarditis is a serious infection of the valves inside the heart. In addition to antibiotic therapy, the involved heart valves may require surgical excision and replacement with artificial valves.