What are the causes, symptoms, diagnosis, treatment, and prevention of Sexually Transmitted Diseases (STDs)?

Comprehensive Guide to Sexually Transmitted Diseases (STDs)

The most effective way to prevent sexually transmitted diseases is to avoid sexual intercourse with infected partners, use condoms consistently and correctly with partners of unknown status, and get tested regularly for STDs. 1

Causes of STDs

• STDs are primarily spread through sexual contact and are caused by various pathogens including bacteria, viruses, and parasites 2
• Bacterial causes include Neisseria gonorrhoeae (gonorrhea), Chlamydia trachomatis (chlamydia), Treponema pallidum (syphilis), and Haemophilus ducreyi (chancroid) 3
• Viral causes include Human Immunodeficiency Virus (HIV), Herpes Simplex Virus (HSV), Human Papillomavirus (HPV), and Hepatitis B Virus (HBV) 4
• Parasitic causes include Trichomonas vaginalis (trichomoniasis) and pubic lice 4

Symptoms of STDs

• Many STDs can be asymptomatic, especially in women, making regular screening essential 5
• Common symptoms in women include abnormal vaginal discharge, vaginal odor, genital itching, pain during urination or intercourse, and abnormal vaginal bleeding 6
• Common symptoms in men include urethral discharge, painful urination, testicular pain or swelling, and genital lesions 3
• Genital ulcers may indicate syphilis, herpes, or chancroid 4
• Systemic symptoms like fever, rash, and lymphadenopathy may occur with certain STDs like syphilis and HIV 4

Diagnosis of STDs

• Proper diagnosis requires a combination of clinical evaluation and laboratory testing 6
• Standard STD screening panel should include tests for:
  • Chlamydia and gonorrhea (annual testing for sexually active women ≤25 years and older women with risk factors) 5
  • HIV testing for all persons at risk of STDs 5
  • Syphilis testing for individuals with high-risk sexual behavior 5
  • Hepatitis B testing, particularly for pregnant women and high-risk individuals 5
• Additional testing based on symptoms and risk factors:
  • Trichomoniasis testing for women with symptoms or high risk 5
  • Bacterial vaginosis testing for women with vaginal discharge or odor 5
  • Comprehensive testing including rectal and pharyngeal sites for men who have sex with men 5
• Microscopic examination with saline solution helps identify trichomonads or clue cells, while KOH preparation helps identify yeast 6
• Molecular methods have improved sensitivity and specificity for STD diagnosis 2

Treatment of STDs

• Bacterial STDs are generally curable with appropriate antibiotics 3
• For chlamydia and gonorrhea, azithromycin is commonly prescribed 7
• For urethritis and cervicitis due to Chlamydia trachomatis or Neisseria gonorrhoeae, azithromycin is indicated 7
• Treatment for bacterial vaginosis includes metronidazole or clindamycin 6
• For vulvovaginal candidiasis, treatment options include topical antifungals or oral fluconazole 6
• For trichomoniasis, metronidazole is the treatment of choice 6
• Viral STDs like herpes and HIV cannot be cured but can be managed with antiviral medications 4
• Treatment of sex partners is essential to prevent reinfection, except in cases like bacterial vaginosis where partner treatment is not recommended 6

Prevention of STDs

• Abstinence from sexual activity is the most effective way to prevent STDs 1
• Both partners should get tested for STDs, including HIV, before initiating sexual intercourse 1
• Consistent and correct use of condoms significantly reduces the risk of STD transmission 1
• Proper condom use includes:
  • Using a new condom with each act of intercourse 1
  • Putting the condom on before any genital contact 1
  • Ensuring adequate lubrication (using only water-based lubricants with latex condoms) 1
  • Holding the condom firmly against the base of the penis during withdrawal 1
• For injection drug users, prevention measures include:
  • Enrolling in a drug treatment program 1
  • Never using injection equipment that has been used by another person 1
  • Obtaining clean needles if legally available 1
• Preexposure vaccination is effective for preventing certain STDs:
  • Hepatitis B vaccination is recommended for all unvaccinated patients being evaluated for an STD 1
  • HPV vaccination is recommended for appropriate age groups 4

Partner Notification and Follow-up

• Patients with STDs should notify sex partners about their exposure and encourage clinical evaluation 1
• Partner notification can be done through patient referral, contract referral, or provider referral 1
• Health departments can assist in notifying partners for certain STDs like HIV, syphilis, gonorrhea, hepatitis B, and chlamydia 1
• Rescreening is recommended at 3 months after treatment for those diagnosed with chlamydia or gonorrhea 5
• More frequent testing (every 3-6 months) is recommended for individuals with ongoing high-risk behaviors 5

Special Considerations

• Pregnant women require special attention as STDs can cause complications during pregnancy and be transmitted to the newborn 1
• Pregnant women with bacterial vaginosis or candidiasis should only use 7-day topical treatments 6
• HIV-infected individuals may require more aggressive or prolonged treatment for certain STDs 6
• For recurrent vulvovaginal candidiasis, maintenance antifungal therapy for 6 months is recommended 6

Common Pitfalls to Avoid

• Self-medication should be avoided except for women previously diagnosed with candidiasis experiencing identical symptoms 6
• Vaginal douching should be avoided as it disrupts normal flora and increases infection risk 6
• Asymptomatic Candida colonization (present in 10-20% of women) should not be treated 6
• Non-barrier contraceptive methods offer no protection against HIV or other STDs 1
• Women using hormonal contraception, who have been surgically sterilized, or who have had hysterectomies should be counseled regarding condom use and STD risk 1