Sexually Transmitted Diseases
Clark, Alice M., Drug Topics
Sexually transmitted diseases (STDs) are the most commonly reported bacterial infections in the United States. Some estimates put the annual occurrence of STDs at 12 million new cases, and it is believed that almost half of the U.S. population will acquire an STD by the age of 35. The costs, in terms of both direct health-care costs and loss of productivity, are staggering. For example, chlamydial infections, with an estimated rate of four million new cases each year, are believed to cost $2 billion annually for diagnosis, care, and treatment.
The trends observed in recent years are particularly disturbing. Physicians are diagnosing more cases of almost all the serious STDs. Human papillomavirus--induced genital warts are among the most rapidly increasing STDs, and the incidence of genital herpes continues to rise. The highest number of cases of syphilis in the past 40 years was reported in 1990. In addition, since the 1970s, an increasing percentage of adolescents are sexually active at younger ages, leading to more susceptibility to STDs. In fact, it has been estimated that 86% of all STDs occur between the ages of 15 and 29.
Survey results indicate that more than 50% of all teenagers have had sexual intercourse, and almost 40% are "sexually active" (sexual intercourse during the last three months); thus, the STDs are occurring in epidemic proportion in the young. Overall, 4% of students in grades 9 to 12 report having had an STD; the rates among black students are more than double those among white and Hispanic students. In addition to the classical STDs--gonorrhea, syphilis, and chancroid--it is now known that at least 50 different organisms can be transmitted sexually, including some that lead to enteric and parasitic disease manifestations.
Furthermore, serious complications of STDs include infertility, ectopic pregnancy, infant morbidity and mortality, neoplasms, and AIDS. The complicating sequelae tend to be more severe in women than in men, and the gap separating minorities from the white population is growing larger. For example, the rate of syphilis in blacks has more than doubled since 1985. As many as one million women each year are treated for pelvic inflammatory disease (PID) as a complication of gonococcal and chlamydial infections, at a cost of $3.5 billion. Human papillomavins, which has been associated with cervical cancer, has been detected in some studies in almost half of all college women and is now believed by many to be the most common viral STD, probably exceeding the total estimated herpes simplex type 2 genital infections of 30 million.
The sexually transmitted diseases can be categorized in several different ways. Physicians may refer to the STDs as notifiable or non-notifiable. Notifiable STDs are required by law to be reported to the Centers for Disease Control & Prevention in Atlanta. Three STDs are notifiable in all states: gonorrhea, syphilis, and AIDS. Chancroids, lymphogranuloma venereum, and granuloma inguinale may all be notifiable diseases, depending on state requirements. STDs may also be considered by the nature of the symptomatic presentation of the disease, i.e., genital ulcer diseases (syphilis, chancroid), inflammatory discharge diseases (gonorrhea, Chlamydia), vaginitis (bacterial vaginosis, trichomoniasis), those not involving the genitalia (AIDS, hepatitis), and so on.
The STDs can also be categorized by microbial etiology. The nature of the causative organism generally determines the choice, as well as the success or failure, of therapeutic regimens. Since the primary goal of this discussion is to review current treatments available, classification of the STDs by microbial etiology will be utilized here. Thus, the STDs will be considered as bacterial, protozoal, viral, or "other" diseases. The discussion will focus on the major sexually transmitted diseases, their causes, occurrence, symptoms, methods of transmission, possible complications, and recommended treatments, including recommendations for epidemiological therapy, i. …