Probiotics – Innovative Strategy for Better Vaginal Health
Transcription
Probiotics – Innovative Strategy for Better Vaginal Health
Probiotics – Innovative Strategy for Better Vaginal Health At an evening symposium held by the Obstetrical & Gynaecological Society of Hong Kong on October 22, 2009, Professor Gilbert Donders from Belgium discussed the challenges of treating and preventing recurrence of local vaginal infections, including bacterial vaginosis, candida vaginitis and trichomoniasis. He explained the importance of maintaining or restoring a normal vaginal flora dominated by lactobacilli, and explored the role of probiotics containing viable lactobacilli, like Gynoflor® (DKSH), in the management of vaginitis, particularly as adjuvant therapy to improve outcomes and reduce the risk of recurrence. Probiotics as an Alternative Treatment for Vaginitis Professor Gilbert GG Donders Department of Obstetrics and Gynaecology Infectious Diseases in OB/GYN H Hart Kliniek Tienen University Hospital Gasthuisberg Leuven University of Leige Leige, Belgium T he three most frequently occurring vaginal disorders worldwide are trichomoniasis, candida vaginitis and bacterial vaginosis (BV). However, other conditions that are also important to consider include aerobic vaginitis (AV), cytolytic vaginosis and mixed infections. Despite the availability of effective antibiotic treatments, the high recurrence rate of local vaginal infections shows that the management of these prevalent conditions needs to be improved. Many patients wish to avoid taking repeated courses of antibiotics, which are often associated with unpleasant side effects and potentially lead to pathogen resistance problems. Improving clinical outcomes for women with vaginitis starts with a good understanding of the healthy vaginal ecosystem. Understanding the vaginal ecosystem The vaginal mucosa is composed of basal cells, parabasal cells, intermediate cells and superficial epithelial cells (Figure 1), which are the cells that desquamate during a vaginal smear. In healthy women, the vaginal epithelium is lined with a microflora ecosystem predominated by lactobacilli. These lactobacilli require an acidic environment (pH 4.0 – 4.5) and they help maintain this acidity by producing lactate (lactic acid). The lactobacilli convert glycogen released from desquamating superficial cells into lactose and then lactate to lower the vagina pH. They also produce bacteriocidal compounds, including hydrogen peroxide, and compete with other bacteria for adhesion to the epithelial cells, thus protecting against an overgrowth of pathogenic bacteria. Professor Donders explained that a healthy full-thickness epithelium is essential for this ecosystem to operate optimally, as the lactobacilli require an adequate supply of glycogen from the proliferation, maturation and desquamation of superficial cells. Thus, the other factor essential to a healthy vaginal ecosystem is an adequate local oestrogen level (Figure 1). Figure 1. The essential elements of a healthy vaginal ecosystem pH=4.3–4.5 Grading disturbances in the vaginal microflora Bacterial vaginosis and aerobic vaginitis BV is characterized by a 100- to 1,000-fold increase in pathogenic bacteria accompanied by a substantial decrease in lactobacilli concentrations. However, this shift in the vagina flora is not associated with leukocyte infiltration, inflammation, pain, itching, dyspareunia, vaginal redness or oedema. “BV is not an inflammatory condition; it can be viewed as an ecological disorder,” explained Professor Donders. A diagnosis of BV according to Amsel involves identification of three of the following four criteria: • Homogeneous grey watery discharge • F ishy smell (increased after menses or sexual intercourse) • pH >4.5 • clue cells on microscopy Using these criteria and microscopy, BV can be diagnosed successfully during the patient consultation. Mucosa Intermediate cells Parabasal cells Basal cells High recurrence rates are typical for BV,2 and may be the result of the development of a therapy-resistant biofilm on the vaginal epithelium. “This is my major point – it is not treatment of BV, but prevention of recurrences of BV that is pH>4.5 the main issue for clinicians,” Professor Donders commented. “For recurrent BV, patients may want to use natural drugs like probiotics, rather than repetitive courses of antibiotics, • Pathogens with their potential for side effects and resistance induction.” Aerobic vaginitis (AV) is characterized by smears that are Intermediate deficient in lactobacilli, positive cells for cocci and parabasal epithelial cells, and/or positive for vaginal leukocytes.3 The Parabasal cellsdamage and/or thinning presence of parabasal cells indicates of the vaginal epithelium (Figure 2). Clinical findings include Basal cells genital inflammation, yellow discharge, vaginal dyspareunia and vaginal ulceration. Aerobic pathogens including group B streptococci, E coli and Staphylococcus aureus are frequently cultured. Abnormal vaginal flora and pregnancy The relationship between abnormal vaginal flora (AVF) in 1010 Control early pregnancy and adverse pregnancy outcomes, specifically Plus L acidophilus KS 400 8 increased 10 risk of preterm delivery (PTD), has been clearly 4,5 established. However, using metronidazole to treat pregnant 106 women with asymptomatic BV or trichomoniasis has shown 104 for preventing PTD; in fact, metronidazole may no benefit increase the risk.6-8 2 10 101 Donders and his colleagues have investigated Professor the relationship between PTD further toalbicans determine S aureus E coliAVFG and vaginalis P bivia C. IH11128 which subtypes pose the most risk in pregnancy.5,9 His prospective studies have shown that full-blown BV in the first trimester has less impact on pregnancy outcome than intermediate types of AVF,5 and that AVF, coccoid-type AV, staphyloid AV and partial BV are the most important predictors of PTD.9 Another recent study has shown that AV before the 17th week of gestation is correlated with placental Normalinflammation Flora Index (NFI) histological and funisitis.10 Relapse rate 16 2.0 Gynoflor® other types 14 Placebo These studies show that of AVF, such as AV, 12.65% partial1.6BV and mixed infections, may be more dangerous in 12 1.4 early pregnancy than BV. In addition, metronidazole is not the 10 1.2 ideal treatment for all women with AVF, and certainly not in 7.9% 8 aspecific therapies may 1.0 pregnancy. Hence, broader and more 0.8 be needed for AVF in pregnancy, such as clindamycin and/or 6 0.4 probiotics, although clinical studies will be needed to support 4 0.4 such regimens. 1.8 % relapse Lactobacillary grading using a wet mount and phase-contrast microscopy is the first investigation Professor Donders uses clinically; if the vaginal ecosystem is shown to be disturbed, diagnosis of the infection can then be performed. He encouraged the audience of clinicians to use microscopy in their daily clinical practice. Superficial cells Colony forming units/mL Increasing LBG (LBG I, IIa, IIb and III) has been shown to be directly correlated with increasing vaginal pH and inversely correlated with lactate concentrations.1 In addition, increasing disturbance of the lactobacillary flora was highly correlated with the presence of genital micro-organisms, including Gardnerella vaginalis, Trichomonas vaginalis, Gram positive cocci (eg, enterococci) and Gram negative rods (eg, Escherichia coli). Lactobacilli Glycogen Acidification H2O2 Adhesion Proliferation NFI change from baseline Professor Donders emphasized that a 40x magnification phase-contract microscope is an essential tool for physicians treating women with suspected vaginal infection. “Preparing a vaginal smear slide and using simple microscopy techniques can quickly provide a great deal of information about the case,” he said. Lactobacillary grades (LBG) can be determined using simple phase-contract microscopy of wet mounts in the clinic. The grading categories are: • G rade I (normal) – predominance of lactobacilli without other bacteria • G rade IIa (intermediate) – predominantly lactobacilli but evidence of other bacteria • G rade IIb (intermediate) – lactobacilli present but outnumbered by many other bacteria (eg, cocci) • Grade III (abnormal) – no lactobacilli, many pathogenic bacteria Lactose Lactate Estrogens 2 0.2 0 0 C1 C2 Gynoflor® Placebo Parabasal cells Basal cells Figure 2. Diagrammatic comparison of the vaginal ecosystem in bacterial vaginosis (left) and aerobic vaginitis (right) pH>4.5 pH>5.0 • Pathogens Intermediate cells Parabasal cells Basal cells The role of therapeutic probiotics in vaginitis Professor Donders outlined the desirable properties of therapeutic lactobacilli as: • High adhesion to the vaginal epithelium to effectively compete with pathogenic bacteria 1010 – L gasseri, L brevis, L acidophilus and 8L rhamnosus 10 display strong epithelial adhesion 106lactic acid, • Antibacterial activity, via production of bacteriocins and hydrogen peroxide 104 • Biosurfactants and co-aggregation of bacteria to ensure 102 destruction of the biofilm BV, metronidazole treatment has been shown to be superior 15-17 pH=4.3–4.5 to probiotic lactobacilli oral and vaginal preparations. Estrogens Lactose Lactobacilli Mucosa Colony forming units/mL % relapse NFI change from baseline Colony forming units/mL Lactate Professor Donders has conducted a randomized, single-blind, active-controlled, multicentre pilot study comparing the Glycogen Control Acidification L acidophilus (12 KS 400days) and H2O2 Adhesion efficacy of Plus Gynoflor® metronidazole (6 days) Proliferation in patients with AVF (n=42) (Donders GGG, et al. Manuscript submitted, Based a variety of efficacy parameters, Superficial2009). cells Gynoflor® was non-inferior to metronidazole 1 week after Intermediate cells treatment, but was slightly less effective than the antibiotic at 1 month. Thus, for a long-term cure, a single course of Parabasal cells therapy with a probiotic is suboptimal, and repetitive courses 101 Basal cells Gynoflor® vaginal tablets are a therapeutic lactobacilli or interval therapy may be needed, explained Professor S aureus E coli G vaginalis P bivia C. albicans preparation containing 0.03 mg estriol and more than 100 Donders. IH11128 million viable L acidophilus. Estriol is included to stimulate proliferation and maturation of the vaginal epithelium, which Probiotics in the adjuvant setting is important to support the growth and survival of lactobacilli. Adjuvant therapy with probiotics is another potential way to The L acidophilus KS 400 strain included in the product is of improve the outcomes of conventional treatments, perhaps pH>4.5 cure rates, preventing candidiasis and other human origin and has been shown to have the properties by improving desirable for therapeutic vaginal use. It promotes a low abnormalities that may emerge after antibiotic therapy, or vaginal pH through fermentation of lactose and glycogen preventing recurrences of BV or candida infections. Normal Flora Index (NFI)to Relapse rate • Pathogens lactic acid, is a strong producer of hydrogen peroxide and 16 2.0 displays competitive adherence to epithelial cells. Professor Donders presented an overview of randomized Gynoflor® 1.8 14 Placebo clinical trials that 12.65% have assessed the efficacy of 1.6 12 In vitro experiments with L acidophilus KS 400 have adjuvant lactobacilli Intermediate therapy (oralcells or vaginal) in the 1.4 10 demonstrated its ability to produce lactic acid and rapidly management of BV; each of the trials found a benefit 1.2 11 7.9% lactobacilli therapy after antimicrobial reduce the pH of the culture medium, produce hydrogen of adjuvant 8 Parabasal cells 1.0 11 peroxide, and inhibit the growth of pathogenic micro- treatment.18-25 In one of the studies, women treated 0.8 6 organisms including G vaginalis, Prevotella brevia, E coli, for BV, candidiasis or Basal trichomoniasis (n=360) cells 0.4 4 S aureus and Candida albicans (Figure 3).12,13 L acidophilus were randomized (2:1) in double-blind fashion 0.4 2 KS 400 was also shown to reduce adherence of G vaginalis, to receive Gynoflor® or placebo after antibiotic 0.2 13 P brevia and E coli to epithelial cells in culture. 0 0 FigureGynoflor® 3. GrowthPlacebo inhibition of vaginal pathogens in C1 C2 Treatment in the acute setting L acidophilus KS 400 in Gynoflor®12,13 C1, follow-up at 3-7 days post-therapy; C2, follow-up atvitro 4-6 weekswith post-therapy A small (n=32) multicentre, randomized, placebo-controlled, clinical trial examined the efficacy of Gynoflor® (1-2 tablets for 1010 Control 6 days) for treatment of BV, including intermediate/partial BV Plus L acidophilus KS 400 8 10 cases.14 The cure rate (defined as ≤1 of the four Amsel clinical criteria positive) 2 weeks after the start of therapy was 77% in 106 the Gynoflor® group and 25% in the placebo group (p<0.05). 104 At 1 month, the cure rates were 88% and 22% (p<0.05), 102 respectively. Furthermore, the results showed that after 6 days of Gynoflor® treatment, the lactobacilli were capable of 101 recolonizing the vagina. S aureus Although probiotics like Gynoflor® have an interesting potential to improve or cure different conditions in AVF, in full-blown E coli G vaginalis IH11128 P bivia C. albicans IH11128 Figure 4. Gynoflor® adjuvant therapy improved the NFI and reduced relapse rate after treatment for vaginitis24 Relapse rate 2.0 16 1.8 Gynoflor® 14 Placebo 1.6 12.65% 12 1.4 % relapse NFI change from baseline Normal Flora Index (NFI) 1.2 1.0 0.8 0.4 10 8 7.9% 6 4 0.4 2 0.2 0 0 C1 C2 Gynoflor® Placebo C1, follow-up at 3-7 days post-therapy; C2, follow-up at 4-6 weeks post-therapy therapy.24 The primary outcome of the study was the effect on the Normal Flora Index (NFI), which comprises numbers of lactobacilli, pathogenic micro-organisms, leukocytes and vaginal pH. This was used to assess the effect on restoration of the normal vaginal microflora. Follow-up visits occurred 3 to 7 days and 4 to 6 weeks after the end of the adjuvant therapy. At both follow-up visits, the NFI had increased significantly more in the Gynoflor® group than the control group (p=0.002 and p=0.006, respectively) (Figure 4).24 In addition, at the second follow-up, the relapse rate was lower in the Gynoflor® group than the placebo group, although the difference was not statistically significant (Figure 4). Thus, Gynoflor® significantly enhanced restoration of the vaginal flora after anti-infective treatment for vaginitis. Professor Donders said that the available evidence for using lactobacilli probiotics as adjuvant therapy in vaginitis shows that, in this setting, probiotics have a prominent role in enhancing the effect of antibiotic treatment, and preventing recurrences of BV and emergence of candidiasis and other types of vaginitis. He also remarked that lactobacilli probiotics have a role in the treatment of atrophic vaginitis in menopausal patients. However, patients need to understand that repetitive courses are required. “Due to its unique properties, Gynoflor® promises to be a prime candidate for these applications,” he concluded. 0.03 mg, which is very low. It is 30 times lower than the dose in preparations used to treat vaginal dryness, and we use those regularly in such patients. The intravaginal administration ensures that serum levels of estriol are almost zero. I use Gynoflor® for young women, older women, and in pregnancy; it is safe for all these women. Q – If Gynoflor® is safe in hormone-dependent tumours, why does the product information list it as a contraindication? Professor Donders: Gynoflor® has been in the market for many years, and this contraindication is a ‘left-over’ of the way drugs were classified. If a drug was categorised as a hormone, it was automatically listed as contraindication in hormone-related cancers. But over the years, we have learned that estriol has no effect on breast cancers. I believe that this contraindication should be removed from the drug leaflet, but obviously this will require the support of appropriate clinical studies. Q – What stain should be used when performing microscopy examination of smears? Professor Donders: No stain is needed. The important thing is to use a phase-contrast microscope, not a light microscope. The superiority of phase contrast has even been proven in a controlled trial. Q – Is sexual activity contraindicated while using Gynoflor®? Professor Donders: It is probably better to avoid sexual activity during any intravaginal drug therapy, but if sexual activity is planned, it would be best to administer Gynoflor® afterwards. But sexual activity is not a formal contraindication. References 1. Donders GG, et al. Am J Obstet Gynecol 2000;182:872-878. 2. Bradshaw CS, et al. J Infect Dis 2006;193:1478-1486. 3. Donders GG, et al. Br J Obstet Gynaecol 2002;109:34-43. 4. Donders G, et al. Am J Perinatol 1993;10:358-361. 5. Donders G, et al. Prenat Neonat Med 1998;3:588-593. 6. Carey JC, et al. N Engl J Med 2000;342:534-540. 7. Klebanoff MA, et al. N Engl J Med 2001;345:487-493. 8. Odendaal HJ, et al. South Afr Med J 2002;92:231234. 9. Donders GG, et al. Br J Obstet Gynaecol 2009;116:1315-1324. 10. Rezeberga D, et al. Acta Obstet Gynecol Scand 2008;87:360-365. 11. Schoeni M, et al. SAZ 1988;126:139142 [in German]. 12. Kanne B, et al. Jatros/Gynaekologie 1986;2:11-28 [in German]. 13. Data on file; DKSH. 14. Parent D, et al. Arzneimittelforschung 1996;46:68-73. 15. Anukam KC, et al. Microbes Infect 2006;8:2772-2776. 16. Hallén A, et al. Sex Transm Dis 1992;19:146-148. 17. Fredricsson B, et al. Gynecol Obstet Invest 1989;28:156-160. 18. Anukam K, et al. Microbes Infect 2006;8:1450-1454. 19. Neri A, et al. Acta Obstet Gynecol Scand 1993;72:17-19. 20. Shalev E, et al. Arch Fam Med 1996;5:593-596. 21. Reid G, et al. FEMS Immunol Med Microbiol 2001;32:37-41. 22. Reid G, et al. FEMS Immunol Med Microbiol 2003;35:131-134. 23. Reid G. J Med Food 2004;7:223-228. 24. Özkinay, et al. Br J Obstet Gynaecol 2005;112:234-240. 25. Larsson PG, et al. BMC Womens Health 2008;8:3. Conclusion Probiotics may have a role in the treatment of BV when antibiotics are contraindicated, although repeated applications may be necessary. The aspecific actions of lactobacilli probiotics mostly likely provide coverage against AV, partial BV and mixed AV/BV, which can be difficult to treat successfully with traditional therapy. The largest role for lactobacilli probiotics is in the prevention of recurrence in patients with recurrent BV and candida, through restoration of the normal vaginal microflora. The role of these agents in the prevention of pregnancy complications warrants investigation. Q&A session Q – Is Gynoflor® safe for use in patients with oestrogendependent cancers? Professor Donders: Definitely. 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