Bacterial Vaginosis, Vulvovaginal Candidiasis, and Trichomoniasis

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1 Bacterial Vaginosis, Vulvovaginal Candidiasis, and Trichomoniasis Society of Armed Forces Medical Laboratory Scientists (SAFMLS) March 28-31, 2011 New Orleans, Louisiana Richard Steece, Ph.D., D(ABMM)

2 Objectives To describe the etiology and epidemiology of bacterial vaginosis (BV), trichomoniasis, and vulvovaginal candidiasis To discuss the new STD Laboratory Treatment Guidelines related to of bacterial vaginosis (BV), trichomoniasis, and vulvovaginal candidiasis To provide a summary of the current clinical and laboratory diagnostic procedures for bacterial vaginosis (BV), trichomoniasis, and vulvovaginal candidiasis

3 Vaginitis Vaginitis vaginal irritation and discharge >10 million clinic visits annually >$500 million in health care annually Causes of Vaginitis Mechanical Chemical Infections >90% of cases caused by 3 agents >3 million clinic visits annually

4 Vaginitis Causes of Infectious Vaginitis Bacterial Vaginosis (40%-45%) Polymicrobial infection Prevotella sp., Mobiluncus sp., Ureaplasma, Mycoplasma, and Gardnerella vaginalis G. vaginalis as a marker, not sole etiology Candida albicans (20%-25%) Trichomonas vaginalis (15%-20%)

5 Symptom presentation Vaginal discharge Clinical findings Vaginitis Differentiation Normal Trichomoniasis Candidiasis Clear to white Itch, discharge, 50% asymptomatic Frothy, gray or yellowgreen; malodorous Cervical petechiae strawberry cervix Itch, discomfort, dysuria, thick discharge Thick, clumpy, white cottage cheese Inflammation and erythema Bacterial Vaginosis Odor, discharge, itch Homogenous, adherent, thin, milky white; malodorous foul fishy Vaginal ph > 4.5 Usually < 4.5 > 4.5 KOH whiff test Negative Often positive Negative Positive Saline wet mount Lacto-bacilli Motile flagellated protozoa, many WBCs Few WBCs Clue cells (> 20%), no/few WBCs KOH wet mount Pseudohyphae or spores if nonalbicans species

6 Bacterial Vaginosis (BV) Characterized by: Vaginal discharge Grey, thin homogeneous discharge Vulvar itching Irritation Odor Fishy amine odor when KOH is added to discharge: Whiff test

7 Bacterial Vaginosis (BV) Caused by: overgrowth of bacterial species normally present in the vagina with anaerobic bacteria BV correlates with a decrease or loss of protective lactobacilli: Vaginal acid ph normally maintained by lactobacilli through metabolism of glucose/glycogen produce lactic acid Hydrogen peroxide (H 2 O 2 ) is produced by some Lactobacilli,sp. H 2 O 2 helps maintain a low ph, which inhibits bacteria overgrowth Loss of protective lactobacilli may lead to BV

8 Bacterial Vaginosis - Epidemiology Most common cause of vaginitis Prevalence varies by population: 5%-25% among college students 12%-61% among STD patients Widely distributed

9 Bacterial Vaginosis - Epidemiology Linked to premature rupture of membranes, premature delivery and low birth-weight delivery, acquisition of HIV, development of PID, and post-operative infections after gynecological procedures Organisms do not persist in the male urethra

10 Bacterial Vaginosis - Epidemiology Risk Factors African American Two or more sex partners in previous six months/new sex partner Douching (prior 6 months) Absence of or decrease in lactobacilli Lack of H 2 O 2 -producing lactobacilli

11 Bacterial Vaginosis - Epidemiology Transmission Currently not considered a sexually transmitted disease, but acquisition appears to be related to sexual activity 15% of women with no history of sexual intercourse were + for BV

12 Bacterial Vaginosis Clinical Presentation and Symptoms 50% asymptomatic Signs/symptoms when present: 50% report malodorous (fishy smelling) vaginal discharge Reported more commonly after vaginal intercourse and after completion of menses

13 Bacterial Vaginosis Associated Medical Complications Pregnancy Miscarriage Premature labor and delivery Post-caesarean delivery endometritis Non-pregnant PID Increased risk of other STD s (HIV) Endometritis

14 Bacterial Vaginosis Treatment CDC - Recommended Regimens: Metronidazole 500 mg orally twice a day for 7 days, OR Metronidazole gel 0.75%, one full applicator (5 grams) intravaginally, once a day for 5 days, OR Clindamycin cream 2%, one full applicator (5 grams) intravaginally at bedtime for 7 days

15 Bacterial Vaginosis Treatment Alternative regimens: Tinidazole 2 g orally once daily for 2 days, OR Tinidazole 1 g orally once daily for 5 days, OR Clindamycin 300 mg orally twice a day for 7 days, OR Clindamycin ovules 100 g intravaginally once at bedtime for 3 days

16 Bacterial Vaginosis Treatment in Pregnancy Pregnant women with symptomatic disease should be treated with Metronidazole 500 mg orally twice a day for 7 days, OR Metronidazole 250 mg orally three times a day for 7 days, OR Clindamycin 300 mg orally twice a day for 7 days Asymptomatic high-risk women (those who have previously delivered a premature infant) Insufficient information to make recommendations at this time

17 Bacterial Vaginosis - Diagnosis Clinical Criteria (Amsel s Diagnostic Criteria) Vaginal ph >4.5 Amsel Criteria: Must have at least three of the following findings: Presence of >20% per HPF of "clue cells" on wet mount examination Positive amine or "whiff" test Homogeneous, nonviscous, milky-white discharge adherent to the vaginal walls

18 Bacterial Vaginosis - Diagnosis Wet Prep ph KOH Gram Stain (Gold Standard) Nugent Score Lactobacilli (i.e., long Gram-positive rods), Gramnegative and Gram-variable rods and cocci (i.e., G. vaginalis, Prevotella, Porphyromonas and peptostreptococci), and curved Gram-negative rods (i.e., Mobiluncus)

19 Organism Scoring Per Field and Interpretation (Nugent Criteria) Type Number seen/opf None < >30 Lac GVC Mob BV Scored Gram Stain Method (Nugent NP JCM. 29; = Normal 4-6 = Intermediate may indicate trichomoniasis, GC or CT abnormal gram stain, but not consistent with BV 7-10 = Consistent with Bacterial Vaginosis Reports suggest a 89% sensitivity for BV and an 83% specificity using the scored gram stain

20 Bacterial Vaginosis - Diagnosis Pip Activity Test Card Quidel OSOM BVBlue test Does not require Microscope 88% sens; 95% spec vs. Nugent 88% sens and 91% spec vs Amsel Bradshaw, Cs et al. JCM 2005; 43: Affirm VP III Becton Dickinson DNA Probe

21 Vulvovaginal Candidiasis (VVC) Characterized by: Vulvar pruritis is most common symptom Thick, white, curdy vaginal discharge ("cottage cheese-like ) Erythema, irritation, occasional erythematous "satellite" lesion External dysuria and dyspareunia Symptoms are not specific for VVC Source: Health Canada, Sexual Health and STI Section, Clinical Slide Gallery

22 Vulvovaginal Candidiasis (VVC) Etiologic agent Candida species are normal flora of the skin and vagina VVC is caused by overgrowth of C. albicans and other non-albicans species Yeast grows as oval budding yeast cells or as a chain of cells (pseudohyphae) Symptomatic clinical infection occurs with excessive growth of yeast Disruption of normal vaginal ecology or host immunity can predispose to vaginal yeast infections

23 Vulvovaginal Candidiasis (VVC) Candida species are normal flora of skin and vagina and are not considered to be sexually transmitted pathogens

24 Candidiasis - Epidemiology Affects most females during lifetime Estimated 75% of women will have >1 episode per lifetime, 40%-45% >2 Most cases caused by C. albicans (85%- 90%) Second most common cause of vaginitis (20%-25%) Estimated cost: $1 billion annually in the U.S.

25 Candidiasis - Treatment Recommended regimens Over-the-Counter Intravaginal Agents: Butoconazole 2% cream, 5 g intravaginally for 3 days Clotrimazole 1% cream 5 g intravaginally for 7-14 days Clotrimazole 2% cream 5 g intravaginally for 3 days Miconazole 2% cream 5 g intravaginally for 7 days Miconazole 4% cream 5 g intravaginally for 3 days Miconazole 100 mg vaginal suppository, 1 suppository for 7 days Miconazole 200 mg vaginal suppository, 1 suppository for 3 days Miconazole 1,200 mg vaginal suppository, 1 suppository for 1 day Tioconazole 6.5% ointment 5 g intravaginally in a single application Prescription Intravaginal Agents Butoconazole, 2% cream(single dose bioadhesive product), 5 g intravaginally for 1 day Nystatin, 100,000 unit vaginal tablet, one tablet for 14 days Terconazole 0.4% cream 5 g intravaginally for 7 days Terconazole 0.8% cream 5 g intravaginally for 3 days Terconazole 80 mg vaginal suppository, 1 suppository for 3 days Oral agent: Fluconazole 150 mg oral tablet, 1 tablet in a single dose Note: The creams and suppositories in this regimen are oil-based and may weaken latex condoms and diaphragms.

26 Clinically Candidiasis - Diagnosis History, signs and symptoms Direct Observation Visualization of pseudohyphae (mycelia) and/or budding yeast (conidia) on KOH or saline wet mount ph normal (4.0 to 4.5) If ph > 4.5, consider concurrent BV or Trichomonas Cultures may be useful in symptomatic women with negative wet mount Gram Stain

27 PMNs and Yeast Buds Saline: 40X objective Folded squamous epithelial cells PMNs Yeast buds Source: Seattle STD/HIV Prevention Training Center at the University of Washington

28 Yeast Pseudohyphae 10% KOH: 10X objective Masses of yeast pseudohyphae Lysed squamous epithelial cell Source: Seattle STD/HIV Prevention Training Center at the University of Washington

29 Candidiasis - Diagnosis Clinically History, signs and symptoms Direct Observation Visualization of pseudohyphae (mycelia) and/or budding yeast (conidia) on KOH or saline wet mount ph normal (4.0 to 4.5) If ph > 4.5, consider concurrent BV or Trichomonas Cultures may be useful in symptomatic women with negative wet mount Gram Stain DNA Probe BD Affirm VPIII Microbial ID Test

30 Trichomonas vaginalis Characterized by: May be asymptomatic in women Vaginitis Frothy gray or yellow-green vaginal discharge Strong odor Pruritus Cervical petechiae ("strawberry cervix") - classic presentation, occurs in minority of cases May also infect Skene's glands and urethra, where the organisms may not be susceptible to topical therapy Source: Claire E. Stevens/Seattle STD/HIV Prevention Training Center at the University of Washington

31 Trichomonas vaginalis Etiologic agent Trichomonas vaginalis - flagellated anaerobic protozoa Only protozoan that infects the genital tract Possible association with Pre-term rupture of membranes and pre-term delivery Increased risk of HIV acquisition

32 Trichomonas vaginalis -Epidemiology Most common treatable STD Estimated 7.4 million cases annually in the U.S. at a medical cost of $375 million Estimated prevalence: 2%-3% in the general female population 50%-60% in female prison inmates and commercial sex workers 18%-50% in females with vaginal complaints

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34 Trichomonas vaginalis -Epidemiology Risk Factors Multiple sexual partners Lower socioeconomic status History of STDs Lack of condom use

35 Trichomonas vaginalis -Epidemiology Transmission Almost always sexually transmitted T. vaginalis may persist for months to years in epithelial crypts and periglandular areas Transmission between female sex partners has been documented

36 Trichomonas vaginalis -Epidemiology Clinical Manifestations May cause up to 11%-13% of nongonococcal urethritis in males Urethral trichomoniasis has been associated with increased shedding of HIV in HIVinfected men Frequently asymptomatic

37 Trichomonas vaginalis - Treatment Recommended Regimens Metronidazole 2 g orally in a single dose OR Tinidazole 2 g orally in a single dose

38 Trichomonas vaginalis - Diagnosis Direct Observation Vaginal ph >4.5 often present Wet Mount (50%-90%) KOH Wiff Prep Trichomonas* Trichomonas

39 Trichomonas vaginalis - Diagnosis Culture (Gold Standard 85%-90% Sensitive) Diamond s, others In-Pouch (BioMed Diagnostics)

40 Trichomonas vaginalis - Diagnosis Point of Care Tests (POCTs) OSOM Trichomonas Rapid Test (Genzyme) Compared to wet mount sensitivity (94.7%), specificity (100%), positive predictive value (100%), negative predictive value (99.9%) Campbell, et. al., J. Clin. Micro Oct;46(10): XenoStrip Tv (Xenotope Diagnostics) Compared to wet mount 6% positive vs. 8.4% XenoStrip Pillay et. al., J.Clin. Micro Aug;42(8):3853-6

41 Trichomonas vaginalis - Diagnosis Nucleic Acid Amplification Tests (NAATs) Gen-Probe Trichomonas Test PCR Tests available (research sites)

42 Trichomonas vaginalis - Diagnosis DNA Probe BD Affirm VPIII Microbial ID Test Trichomonas Candida species Gardnerella

43 AFFIRM PROBE TECHNOLOGY Sample Lysis & Preparation: 10 minutes Two distinct nucleic acid probes for each organism capture probe (PAC) color development probe (well #2) 33 minutes on instrument Candida sp. 1 x 10 (4) CFU/ml Trichomonas vaginalis 5 x 10 (3) trichomonads/ml Gardnerella vaginalis 2 x 10 (5) CFU/ml PAC goes in well #1 with sample Reagent Casette

44 Place Reagent Cassette On Processor & Press Run

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46 AFFIRM VPIII vs Wet Mount N=425 AFFIRM VPIII Number POS Wet Mount Number POS Trichomonas 30 (7%) 23 (5%) Candida 45 (11%) 31 (7%) BV 190 (45%) 58 (14%) Brown HL et al. ID OBGYN :17-21

47 Why Use A Probe For Detection Of Vaginitis? Advantages Rapidity of results Increased Sensitivity Multiple infections detected May be used in outpatient facilities Reproducibility of testing Less expensive than NAATs Disadvantages Cannot run assay for only one analyte; but we probably should look for co-infections Few requests made to clinical laboratories: need to educate Cost as compared to what is now done in most laboratories

48 Summary Infectious vaginitis is most often caused by 3 entities: T. vaginalis Candida sp. Bacterial vaginosis polymicrobial Sexually Transmitted Diseases Treatment Guidelines, 2010 Recommendations for treatment Various clinical observations/tests are available BD Affirm is an economical, sensitive, and specific test which is able to detect all three causes of infectious vaginitis

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