Porth's Essentials of Pathophysiology, 4e

1061

Sexually Transmitted Infections

C h a p t e r 4 1

Venereal Disease Research Laboratory (VDRL) or the rapid plasma reagin (RPR) tests. The tests, which are easy to perform, rapid, and inexpensive, are frequently used as screening tests for syphilis. Because these tests are nonspecific, positive results can occur for diseases other than syphilis. Results become positive 4 to 6 weeks after infection or 1 to 3 weeks after the appearance of the primary lesion. The disease’s incubation period may delay test sensitivity; therefore, serologic tests usually are repeated after 6 weeks if the initial test results were negative. The specific treponemal tests measure antibodies capa- ble of reacting with T. pallidum antigens. These tests are used to determine whether a positive result on a non- specific test such as the VDRL is attributable to syphilis. Some clinical laboratories and blood banks have begun to screen samples using automated treponemal tests, the enzyme-linked immunosorbent (EIA) or chemoilu- minescence (CIA) assays, and then follow-up with a nontreponemal test (VDRL or RPR). 4 The CDC recom- mends that persons with a positive screening test should have a standard nontreponemal titer performed by the laboratory. If the test is negative, it is recommended that the laboratory perform a different test using a different antigen. 4 The treatment of choice for syphilis is penicillin. 8 Because of the spirochetes’ long generation time, effec- tive tissue levels of penicillin must be maintained for several weeks. Long-acting injectable forms of penicil- lin are used. Tetracycline or doxycycline is used for treatment in persons who are sensitive to penicillin, but these medications cannot be used in pregnancy. Sexual partners should be evaluated and treated pro- phylactically even though they may show no sign of infection. All treated individuals should be reexam- ined clinically and serologically at 6 and 12 months after completing therapy; more frequent monitoring (3-month intervals) is suggested for individuals with HIV infection. 8 ■■ The vaginal-urogenital systemic STIs—chlamydial infections, gonorrhea, and syphilis—can severely affect the genital structures and manifest as systemic infections. ■■ Gonorrheal and chlamydial infections can cause a wide variety of genitourinary complications in men and women, and both can cause ocular disease and blindness in neonates born to infected mothers. ■■ Syphilis is caused by a spirochete, T. pallidum. It can produce widespread systemic effects and is transferred to the fetus of infected mothers through the placenta. SUMMARY CONCEPTS

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1. A 25-year-old woman has been told that her Pap test indicates infection with HPV type 16. A. What are the possible implications of infection with HPV 16? B. How might she have acquired this infection? C. What treatments are currently available for treatment of this infection? 2. A 35-year-old woman presents with vulvar pruritus, dysuria, dyspareunia, and an odorless, thick, cheesy vaginal discharge. She has diabetes mellitus and has recently recovered from a respiratory tract infection, which required antibiotic treatment. A. Given that these manifestations are consistent with a Candida infection, what tests might be used to confirm the diagnosis? B. What risk factors does this woman have that predispose her to this type of vaginitis? C. How might this infection be treated? 1. Frenkl TL, Potts J. Sexually transmitted diseases. Urol Clin North Am. 2008;35:33–46. 2. Beckmann CRB, Ling FW, Barzansky BM, et al.; for American College of Obstetrics and Gynecology. Obstet Gynecol . 3rd ed. Philadelphia, PA: Wolters Kluwer Health/Lippincott Williams & Wilkins; 2010:241–258. 3. Centers for Disease Control and Prevention. Incidence, prevalence, and cost of sexually transmitted infections in the United States. 2013. Available at: http://www.cdc.gov/std/stats/ STI-Estimates-Fact-Sheet-Feb-2013.pdf. Accessed July 24, 2013. 4. Centers for Disease Control and Prevention. Sexually transmitted diseases: treatment guidelines 2010. MMWR Morb Mortal Wkly Rep. 2010;59(RR12):1–116. 5. Stanley MA. Genital human papillomavirus infections: current and prospective therapies. J Gen Virol. 2012;93:681–695. 6. Hariri S, Dunna E, Saralya M, et al. Human papillomavirus. In: Centers for Disease Control and Prevention. VPD Surveillance Manual . 5th ed. Chapter 5. 2011. Available at: http://www.cdc. gov/vaccines/pubs/surv-manual/chpt05-hpv.pdf. Accessed July 29, 2013. 7. Center for Disease Control and Prevention. FDA licensure of bivalent human papillomavirus vaccine (HPV2, Cervarix) for use in females and updated HPV vaccination recommendations from the Advisory Committee on Immunization Practices (ACIP). MMWR Morb Mortal Wkly Rep. 2010;59(20): 626–629. 8. Center for Disease Control and Prevention. FDA Licensure of qualivalent vaccine (HPV4, Gardasil) for use in males and guidance from the Advisory Committee on immunization practices (ACIP). MMWR Morb Mortal Wkly Rep. 2010;59(20):630–632. 9. McAdam AJ, Sharpe AH. Infectious diseases. In: Kumar V, Abbas AK, Fausto N, eds. Robbins and Cotran Pathologic Basis of Disease . 8th ed. Philadelphia, PA: Saunders Elsevier; 2010: 351–352, 366, 374–377, 380.

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