Recurrent group A streptococcal vulvovaginitis in adult women: family epidemiology

Recurrent Infectious Vaginitis: A Practical Approach for the Primary Care Clinician

Recurrent infectious vaginitis can lead to significant morbidity, patient frustration, and health care costs. The most common causes are bacterial vaginosis (BV) and vulvovaginal candidiasis (VVC); however, other infectious and noninfectious etiologies should be considered in patients with recurrent symptoms. A detailed history and physical examination with appropriate testing at the time of symptoms is critical to establishing a correct diagnosis. Management options for recurrent BV and VVC are limited. Complex cases including those with atypical symptoms, negative testing for common causes, refractory symptoms despite appropriate therapy or recurrences during suppressive therapy will require referral to specialist care.

Identification and Functional Characterization of Peptides With Antimicrobial Activity From the Syphilis Spirochete, Treponema pallidum

The etiological agent of syphilis, Treponema pallidum ssp. pallidum, is a highly invasive “stealth” pathogen that can evade the host immune response and persist within the host for decades. This obligate human pathogen is adept at establishing infection and surviving at sites within the host that have a multitude of competing microbes, sometimes including pathogens. One survival strategy employed by bacteria found at polymicrobial sites is elimination of competing microorganisms by production of antimicrobial peptides (AMPs). Antimicrobial peptides are low molecular weight proteins (miniproteins) that function directly via inhibition and killing of microbes and/or indirectly via modulation of the host immune response, which can facilitate immune evasion. In the current study, we used bioinformatics to show that approximately 7% of the T. pallidum proteome is comprised of miniproteins of 150 amino acids or less with unknown functions. To investigate the possibility that AMP production is an unrecognized defense strategy used by T. pallidum during infection, we developed a bioinformatics pipeline to analyze the complement of T. pallidum miniproteins of unknown function for the identification of potential AMPs. This analysis identified 45 T. pallidum AMP candidates; of these, Tp0451a and Tp0749 were subjected to further bioinformatic analyses to identify AMP critical core regions (AMPCCRs). Four potential AMPCCRs from the two predicted AMPs were identified and peptides corresponding to these AMPCCRs were experimentally confirmed to exhibit bacteriostatic and bactericidal activity against a panel of biologically relevant Gram-positive and Gram-negative bacteria. Immunomodulation assays performed under inflammatory conditions demonstrated that one of the AMPCCRs was also capable of differentially regulating expression of two pro-inflammatory chemokines [monocyte chemoattractant protein-1 (MCP-1) and interleukin-8 (IL-8)]. These findings demonstrate proof-of-concept for our developed AMP identification pipeline and are consistent with the novel concept that T. pallidum expresses AMPs to defend against competing microbes and modulate the host immune response.

Transcriptomic Analysis of Streptococcus pyogenes Colonizing the Vaginal Mucosa Identifies hupY, an MtsR-Regulated Adhesin Involved in Heme Utilization

Colonization of the host requires the ability to adapt to an environment that is often low in essential nutrients such as iron. Here we present data showing that the transcriptome of the important human pathogen Streptococcus pyogenes shows extensive remodeling during in vivo growth, resulting in, among many other differentially expressed genes and pathways, a significant increase in genes involved in acquiring iron from host heme. Data show that HupY, previously characterized as an adhesin in both S. pyogenes and the related pathogen Streptococcus agalactiae, binds heme and affects intracellular iron concentrations. HupY, a protein with no known heme binding domains, represents a novel heme binding protein playing an important role in bacterial iron homeostasis as well as vaginal colonization.

Streptococcus pyogenes (group A streptococcus [GAS]) is a serious human pathogen with the ability to colonize mucosal surfaces such as the nasopharynx and vaginal tract, often leading to infections such as pharyngitis and vulvovaginitis. We present genome-wide transcriptome sequencing (RNASeq) data showing the transcriptomic changes GAS undergoes during vaginal colonization. These data reveal that the regulon controlled by MtsR, a master metal regulator, is activated during vaginal colonization. This regulon includes two genes highly expressed during vaginal colonization, hupYZ. Here we show that HupY binds heme in vitro, affects intracellular concentrations of iron, and is essential for proper growth of GAS using hemoglobin or serum as the sole iron source. HupY is also important for murine vaginal colonization of both GAS and the related vaginal colonizer and pathogen Streptococcus agalactiae (group B streptococcus [GBS]). These data provide essential information on the link between metal regulation and mucosal colonization in both GAS and GBS.

Streptococcus pyogenes: an unusual cause of salpingitis. Case report and review of the literature

BACKGROUND

Streptococcus pyogenes can colonize genitourinary tract, but it is a rare cause of salpingitis.

CASE REPORT

We report a case of bilateral salpingitis due to Streptococcus pyogenes in a 34-year-old woman using an intra-uterine device and which occurred following a family history of recurrent S. pyogenes infections. We review 12 other cases reported in the literature, and discuss the pathophysiological mechanisms of this potentially life-threatening disease.

CONCLUSION

It is important to take into account consider Streptococcus pyogenes as a cause of acute salpingitis in the context of recent intra-familial Streptococcus pyogenes infections.

Group A streptococcus: is there a genital carrier state in women following infection?

Group A streptococcus (GAS) is a rare but serious cause of postpartum and gynecological infections. There are no follow-up or prophylaxis guidelines for women with previous GAS genital infection. We aimed to evaluate the incidence of long-term gynecological carrier state in patients with a history of genital GAS infection. This is a prospective study of women who had a genital GAS infection and were followed for 1 year from the date of isolation. Cultures were obtained every 3-4 months. As a control group, women with no previously documented GAS infection were screened for GAS. Twenty-five women with a previous GAS infection participated in the study. Two of the 25 patients had positive vaginal GAS cultures during follow-up, giving a carrier rate of 8 %. Four hundred and thirty-six women participated in the control group; none was a carrier of GAS (p < 0.003). We found that common gynecological procedures were occasionally associated with invasive GAS infection. A significant rate of carriers was found among women with previous GAS genital infection. Common office procedures can be related to severe GAS infection. Consideration should be given to screening women with previous GAS infection prior to invasive as well as semi-invasive gynecological or obstetric procedures.

Streptococcal toxic shock syndrome secondary to group A Streptococcus vaginitis

Streptococcal toxic shock syndrome (TSS) is a systemic illness usually caused in the setting of infection by group A Streptococcus (GAS). The primary infections are often invasive infections of the respiratory tract or necrotizing infections of the skin and soft tissue, but some infections occur without relevant focus. GAS vaginitis is a rare condition among adult women and is accordingly thought to be uncommon as a cause of streptococcal TSS. Here we report the cases of two postmenopausal women with streptococcal TSS secondary to GAS vaginitis, one aged 55 and one aged 60. Both came to our emergency department with complaints or symptoms of abdominal pain, fever, hypotension, and multi-organ failure. In both cases, the relevant factor associated with streptococcal infection was a recent episode of GAS vaginitis. Both underwent fluid management and 14 days of antibiotic treatment and fully recovered without complications. Vaginitis was likely to be the primary infectious trigger of TSS in these two cases. Intrauterine device insertion, endometrial biopsy, and post-partum state have all been previously reported in TSS patients, and the female genital tract has been described as a portal of entry. GAS vaginitis warrants appropriate treatment as it may progress to severe systemic infection as described.

Induction of a quorum sensing pathway by environmental signals enhances group A streptococcal resistance to lysozyme

The human-restricted pathogen Streptococcus pyogenes (Group A Streptococcus, GAS) is responsible for wide-ranging pathologies at numerous sites in the body but has the proclivity to proliferate in individuals asymptomatically. The ability to survive in diverse tissues is undoubtedly benefited by sensory pathways that recognize environmental cues corresponding to stress and nutrient availability and thereby trigger adaptive responses. We investigated the impact that environmental signals contribute to cell-to-cell chemical communication [quorum sensing (QS)] by monitoring activity of the Rgg2/Rgg3 and SHP-pheromone system in GAS. We identified metal limitation and the alternate carbon source mannose as two environmental indicators likely to be encountered by GAS in the host that significantly induced the Rgg-SHP system. Disruption of the metal regulator MtsR partially accounted for the response to metal depletion, whereas ptsABCD was primarily responsible for QS induction due to mannose, but each sensory system induced Rgg-SHP signaling apparently by different mechanisms. Significantly, we found that induction of QS, regardless of the GAS serotype tested, led to enhanced resistance to the antimicrobial agent lysozyme. These results indicate the benefits for GAS to integrate environmental signals with intercellular communication pathways in protection from host defenses.

Observational study of Streptococcus pyogenes isolated from vaginal swabs of adult women in a hospital and community laboratory

AIMS

Streptococcus pyogenes or group A streptococcus (GAS) is a common cause of vulvo-vaginitis in pre-pubertal females but is uncommonly isolated from the vaginal swabs of adult females. We aimed to describe the clinical and laboratory findings of adult females with GAS isolated from vaginal swabs in a community and hospital laboratory.

METHODS

Over a 19 week period the two laboratories identified females ≥ 15 years of age with GAS isolated from vaginal swabs. At least 2 weeks after reporting, the referring doctor or midwife was telephoned by the authors for clinical information or the clinical notes were reviewed. Laboratory data were also collected.

RESULTS

One hundred adult females with GAS isolated from vaginal swabs were identified from approximately 4500-5000 community laboratory, and 20 from approximately 2000 hospital laboratory swabs. Community patients were more likely to have presented with vaginal symptoms such as discharge, while hospital patients were more likely to have ascending infection related to pregnancy/recent delivery. Of the community patients, 15% were asymptomatic compared with 5% of the hospital patients. Review of Gram stain and culture quantification was not found to be particularly useful for discriminating between clinical infection and asymptomatic colonisation.

CONCLUSIONS

Isolation of GAS from the vaginal swabs of adult females is uncommon. In the community setting it may represent infection with vulvo-vaginitis or asymptomatic colonisation. In the hospital setting, its isolation is frequently associated with pregnancy-related infectious complications.

Gram-positive bacterial superantigen outside-in signaling causes toxic shock syndrome

Staphylococcus aureus and Streptococcus pyogenes (group A streptococci) are Gram-positive pathogens capable of producing a variety of bacterial exotoxins known as superantigens. Superantigens interact with antigen-presenting cells (APCs) and T cells to induce T cell proliferation and massive cytokine production, which leads to fever, rash, capillary leak and subsequent hypotension, the major symptoms of toxic shock syndrome. Both S. aureus and group A streptococci colonize mucosal surfaces, including the anterior nares and vagina for S. aureus, and the oropharynx and less commonly the vagina for group A streptococci. However, due to their abilities to secrete a variety of virulence factors, the organisms can also cause illnesses from the mucosa. This review provides an updated discussion of the biochemical and structural features of one group of secreted virulence factors, the staphylococcal and group A streptococcal superantigens, and their abilities to cause toxic shock syndrome from a mucosal surface. The main focus of this review, however, is the abilities of superantigens to induce cytokines and chemokines from epithelial cells, which has been linked to a dodecapeptide region that is relatively conserved among all superantigens and is distinct from the binding sites required for interactions with APCs and T cells. This phenomenon, termed outside-in signaling, acts to recruit adaptive immune cells to the submucosa, where the superantigens can then interact with those cells to initiate the final cytokine cascades that lead to toxic shock syndrome.

Group A streptococcal vaginitis: an unrecognized cause of vaginal symptoms in adult women

PURPOSE

Vaginal infection with group A streptococci (GAS) is an established cause of vaginitis amongst prepubescent girls, but largely unrecognized in adult women and therefore often misdiagnosed as vulvovaginal candidosis. We sought to give an overview of the epidemiology, risk factors, symptoms, signs, and treatment of GAS vaginitis in adult women.

METHODS

Systematic literature search.

RESULTS

We identified nine case reports covering 12 patients with documented GAS vulvovaginitis. GAS vulvovaginitis in adult women is often associated with a predisposing factor: (1) household or personal history of dermal or respiratory infection due to GAS, (2) sexual contact, and (3) lactational or menopausal vaginal atrophy. Symptoms of GAS vulvovaginitis in adult women may include vaginal and/or vulvar pain, dyspareunia, burning sensation or irritation, and pruritus. In most cases, there is also profuse or copious vaginal discharge which may be watery, yellow, or even purulent. Whilst there are neither clinical trials nor treatment guidelines, treatment with oral penicillin or with vaginal clindamycin cream has been reported to result in rapid cure. In breast-feeding and postmenopausal women with vaginal atrophy, additional treatment with local estriol may be necessary to prevent recurrence. Finally, in case of recurrent GAS vulvovaginitis it will be necessary to assess the patients' asymptomatic household members for pharyngeal and anal carriage and to treat them accordingly.

CONCLUSION

Vaginal infection with GAS in adult women is a clearly defined entity and should be considered a diagnosis when more common causes of vaginitis have been ruled out.

Interactions of Lactobacilli with pathogenic Streptococcus pyogenes

Objective. To determine whether (1) a decreased concentration of Lactobacilli allows S. pyogenes to grow; (2) S. pyogenes is able to grow in the presence of healthy Lactobacillus concentrations; (3) S. pyogenes is capable of inhibiting Lactobacilli. Methods. One hundred fifty patient samples of S. pyogenes were mixed with four different concentrations of L. crispatus and L. jensenii. Colony counts and pH measurements were taken from these concentrations and compared using t-tests and ANOVA statistical analyses. Results. Statistical tests showed no significant difference between the colony counts of S. pyogenes by itself and growth when mixed with Lactobacilli, and no significant difference between the colony counts of S. pyogenes in the four different concentrations of Lactobacilli. Conclusion. The statistical data representing the growth of these two organisms suggests that Lactobacilli did not inhibit the growth of S. pyogenes. Also, S. pyogenes did not inhibit the growth of Lactobacilli.

Longitudinal analysis of the vaginal microflora in pregnancy suggests that L. crispatus promotes the stability of the normal vaginal microflora and that L. gasseri and/or L. iners are more conducive to the occurrence of abnormal vaginal microflora

BACKGROUND

Despite their antimicrobial potential, vaginal lactobacilli often fail to retain dominance, resulting in overgrowth of the vagina by other bacteria, as observed with bacterial vaginosis. It remains elusive however to what extent interindividual differences in vaginal Lactobacillus community composition determine the stability of this microflora. In a prospective cohort of pregnant women we studied the stability of the normal vaginal microflora (assessed on Gram stain) as a function of the presence of the vaginal Lactobacillus index species (determined through culture and molecular analysis with tRFLP).

RESULTS

From 100 consecutive Caucasian women vaginal swabs were obtained at mean gestational ages of 8.6 (SD 1.4), 21.2 (SD 1.3), and 32.4 (SD 1.7) weeks, respectively. Based on Gram stain, 77 women had normal or Lactobacillus-dominated vaginal microflora (VMF) during the first trimester, of which 18 had grade Ia (L. crispatus cell morphotypes) VMF (23.4%), 16 grade Iab (L. crispatus and other Lactobacillus cell morphotypes) VMF (20.8%), and 43 grade Ib (non-L. crispatus cell morphotypes) VMF (55.8%). Thirteen women with normal VMF at baseline, converted in the second or third trimester (16.9%) to abnormal VMF defined as VMF dominated by non-Lactobacillus bacteria. Compared to grade Ia and grade Iab VMF, grade Ib VMF were 10 times (RR = 9.49, 95% CI 1.30 - 69.40) more likely to convert from normal to abnormal VMF (p = 0.009). This was explained by the observation that normal VMF comprising L. gasseri/iners incurred a ten-fold increased risk of conversion to abnormal VMF relative to non-L. gasseri/iners VMF (RR 10.41, 95% CI 1.39-78.12, p = 0.008), whereas normal VMF comprising L. crispatus had a five-fold decreased risk of conversion to abnormal VMF relative to non-L. crispatus VMF (RR 0.20, 95% CI 0.05-0.89, p = 0.04).

CONCLUSION

The presence of different Lactobacillus species with the normal vaginal microflora is a major determinant to the stability of this microflora in pregnancy: L. crispatus promotes the stability of the normal vaginal microflora while L. gasseri and/or L. iners predispose to some extent to the occurrence of abnormal vaginal microflora.

Group A Streptococcus vulvovaginitis in breastfeeding women

Group A beta-hemolytic streptococcus-associated vulvovaginitis is uncommon in adult women. Clinicians should include group A beta-hemolytic streptococcus as a possible cause of vulvovaginal symptoms in breastfeeding women. Along with appropriate antibiotic therapy, vaginal estrogen therapy may be considered to diminish susceptibility to recurrent infection in women with vaginal atrophy.

Lactational amenorrhea as a risk factor for group a streptococcal vaginitis

We report a case of Streptococcus pyogenes, beta-hemolytic Streptococcus, Lancefield group A vulvovaginitis in an otherwise healthy adult female patient experiencing lactational amenorrhea. Group A streptococcal infection is the infective cause of vulvovaginitis in 21% of prepubescent girls, but it is an uncommon cause of vulvovaginitis in adults. Group A streptococcal vulvovaginitis is frequently associated with households that have had a recent outbreak of respiratory or dermal infection. The case described here appears to be unusual in that it was sexually transmitted, and the lack of estrogen associated with anovualtion may have been a predisposing factor for this unusual sexually transmitted disease.