Evidence-Based Medicine for Student Health Services
Robert J. Flaherty, MD
Swingle Student Health Service
Montana State University
Bozeman, MT 59717
 
Sexually Transmitted Diseases 
  
Etiology Monitoring
Epidemiology Prognosis
Diagnosis Prevention
Treatment Patient Education
  
General Information
    
EBM for Student Health   
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About EBM   
   
EBM Resources  
  
Specific Conditions/Diseases 
 
   
     
 		    
Etiology  
No evidence is cited.  
   
Epidemiology  
No evidence is cited.  
   
Diagnosis  
Screening for Sexually Transmitted Diseases 
Pregnant women are the only group that can be recommended for general STD screening in the primary care setting. Other specific screening guidelines, including partner screening are provided. (See Guidelines for details)  Urine-based ligase chain reaction screening, not pelvic examination, is the most cost-effective strategy to detect chlamydial and gonococcal genital infection in asymptomatic sexually active adolescent females and, owing to ease of implementation, the most likely to prevent the greatest number of cases of PID.  AIDS/HIV 
Clinical Diagnosis 
Physicians should obtain a history of risk factors for their patients, and identify, when possible, the current reasons for testing. The purpose of testing for HIV must be to benefit patients, enable them to obtain care and counseling and make their behavior safer for themselves and others. Testing should always be done with the patient's informed consent after a full discussion of the consequences of being tested, including if, when and under what circumstances test results might be disclosed to others. For those infected with HIV, counseling involves not only resolving the psychological and social consequences of this situation, but also continuing medical follow-up, promotion of safer behavior and partner notification.  Laboratory/X-ray Diagnosis 
No evidence is cited. 

Chlamydia 
Clinical Diagnosis 
No evidence is cited. 

Laboratory/X-ray Diagnosis 
The following Chlamydia screening strategies (using cervical or urine samples for PCR) were studied: 

    • No screening 
    • Screening using CDC criteria (mucopurulent cervicitis, all women <20 years, women 20-23 years not using barrier contraceptives or with new sex partner in last 3 months, and older women not using barrier contraceptives and with new sex partner in last 3 months) 
    • Screening women <30 years 
    • Screening all women
All the screening strategies reduced the total costs since costs of the screening strategies were more than offset by reduced costs of the medical consequences of infection. The most cost-effective strategy for screening women was to screen women <30 years old using urine samples for PCR.  Epididymitis  
Diagnosis depends upon the results of a Gram stain of urethral secretions AND unspun urine. These recommendations have been developed by the Canadian  Medical Association using EBM concepts.  Genital Herpes  
No evidence is cited. 

Gonorrhea 
Clinical Diagnosis 
No evidence is cited. 

Laboratory/X-ray Diagnosis 
The overall performance of LCR testing with swabs or first voided urine was better than that of culture for the diagnosis of genital or extragenital gonorrhea.  

Human Pappilomavirus (HPV) - See HPV/Warts  
  
Vaginitis/Vaginosis 
Guidelines have been developed by the Health Canada Laboratory Centre for Disease Control for the diagnosis of bacterial vaginosis, Candidiasis and Trichomonas. (See Guidelines for details)  Vaginal infections can be adequately diagnosed without a speculum exam.        
Treatment  
General  
1998 Guidelines for Sexually Transmitted Disease (STD) has been issued by the Centers for Disease control. This is an update of the 1993 recommendations. (See Guidelines for details). 
  • Caveats
    • Age group studied: All ages
    • Type/size: Systematic review and consensus conference 
    • Population characteristics: Most evidence is from the management of patients in public STD clinics, but recommendations should be applicable to other patient-care settings as well
    • Outcome measures: Microbiologic cure, alleviation of signs and symptoms, prevention of sequelae, and prevention of transmission
  • Citations
    •  
AIDS/HIV  
No evidence is cited. 

Chlamydia  
Comparison of a 1g single oral dose of azithromycin with 100 mg oral doxycycline twice daily for seven days in chlamydial infections found virtually identical clinical and microbial cure rates at two weeks and somewhat better cure rates with azithromycin at 5 weeks (fewer relapses). Adverse events were mild and similar between treatments. The higher medicine costs of azithromycin were offset by lower costs associated with pelvic inflammatory disease, chronic pelvic pain, ectopic pregnancy and tubal infertility.  

  • Caveats
    • Age group studied: Adults
    • Type/size: Meta-analysis (9 studies=1800 patients)
    • Population characteristics: Mostly adult males, some adult females
    • Outcome measure: Clinical and/or microbial cure
  • Citations
Epididymitis 
Treatment depends upon the results of a Gram stain of urethral secretions AND unspun urine.   Genital Herpes  
Oral (not topical) acyclovir  is recommended for treatment: 
  • 200mg 5x/day x 7-10d for initial infection
  • 200mg 5x/day x 5 d for recurrences
  • 200mg 3x/day to prevent recurrences (safe x 4+ years)
Initiation of treatment 6 days or more after onset of symptoms is unlikely to be of benefit.  Gonorrhea 
No evidence is cited. 

Human Papilloma Virus/HPV - See HPV/Warts  
  
Vaginitis/Vaginosis 
Oral metronidazole, metronidazole vaginal gel, and clindamycin vaginal cream were all found to be effective in the short-term treatment of bacterial vaginosis but any difference in effectiveness of these treatments could not be determined. Women using intravaginal products reported higher levels of satisfaction than women taking oral metronidazole. 

Guidelines have been developed by the Health Canada Laboratory Centre for Disease Control for the treatment of bacterial vaginosis, Candidiasis and Trichomonas (See Guidelines for details)    
Monitoring 
No evidence is cited. 
  
Prognosis   
No evidence is cited.   
   
Prevention  
Nonoxynol-9-containing spermicides have an appreciable protective effect against both gonorrhea and chlamydial infection, and wider use of spermicides might substantially reduce the incidence of these diseases. However, insufficient data exist to judge their effect on HIV transmission.   
Patient Education 
The following patient education materials are consistent with the available evidence. 
Rev. 8/4/99
 
This Web site developed and maintained by Robert J. Flaherty, MD  
Comments, additions and corrections are encouraged.