ABSTRACT
La vaginitis es un trastorno ginecológico frecuente producido por distintas causas, algunas de las cuales permanecen desconocidas. Bacteroides fragilis es el anaerobio más importante en bacteriología clínica. Algunas cepas son enterotoxigénicas y se asocian con síndromes intestinales y extraintestinales. Recientemente han sido aisladas de pacientes con vaginitis. En este trabajo se planteó investigar la posible asociación de B. fragilis enterotoxigénico con la vaginitis infecciosa. Fueron procesadas 265 muestras de exudado vaginal. 202 de mujeres sintomáticas y 63 mujeres sanas. La identificación de los microorganismos se realizó por métodos convencionales. En 31,2% de las pacientes sintomáticas se identificaron: Gardnerella vaginalis, Candida albicans, Mobiluncus, Mycoplasma hominis, Ureaplasma urealyticum y Streptococcus agalactiae. En 27 pacientes sintomáticas y en 5 mujeres sanas se identificó B. fragilis. Estas cepas fueron cultivadas en medio líquido e incubadas durante 48 h a 36° C en anaerobiosis. La toxicidad en los sobrenadantes se ensayó en células HT-29. 18 cepas de B. fragilis aisladas de pacientes sintomáticas fueron enterotoxigénicas, ya que indujeron alteraciones en la monocapa celular y en las células. No se identificó en mujeres sanas (P<0,05). 77,7% de las cepas de B. fragilis enterotoxigénicas no se encontraron asociadas con otros patógenos específicos. Este hecho sugiere que pudiera ser un agente causante de vaginitis, ya que el efecto de la enterotoxina sobre la E-cadherina del epitelio vaginal podría facilitar la invasión y su posible papel patógeno en la vagina. Esta es la primera investigación que asocia a Bacteroides fragilis enterotoxigénico como posible causa de vaginitis infecciosa.
Vaginitis is a common gynecologic disorder. It is due to several causes, some even unknown. Bacteroides fragilis is the most important anaerobe in clinical bacteriology, some strains of this group are notable for being enterotoxigenic and they have been associated with intestinal and extraintestinal syndromes. They have recently been isolated from patients with vaginitis. The purpose of this study was to investigate a possible association of enterotoxigenic B. fragilis with infectious vaginitis. 265 samples of vaginal exudate were processed, 202 from symptomatic patients and 63 healthy women. The identification of the microorganisms was carried out by conventional methods. In 31.2% of symptomatic patients were identified: Gardnerella vaginalis, Mobiluncus, Candida albicans, Mycoplasma hominis, Ureaplasma urealyticum and Streptococcus agalactiae. B. fragilis was identified in 27 symptomatic patients and 5 healthy women. These strains were cultivated in liquid medium and incubated during 48 h at 36°C in anaerobe chambers. Supernatant activity was assayed in HT-29 cells. Eighteen B. fragilis strains isolated from symptomatic patients were enterotoxigenic, because induced alterations in target cell morphology. It was not identified in healthy women (P<0.05). 77.7% of enterotoxigenic B. fragilis strains were not associated with other specific pathogens. This fact suggests that enterotoxigenic B. fragilis could be a cause for vaginitis. The effect of enterotoxin on E-cadherin of vaginal epithelium could facilitate invasion and its possible pathogenic role in the vagina. This is the first report that associates enterotoxigenic Bacteroides fragilis as a possible cause of infectious vaginitis.
Subject(s)
Adolescent , Adult , Female , Humans , Middle Aged , Young Adult , Bacteroides fragilis/pathogenicity , Enterotoxins/analysis , Vaginosis, Bacterial/microbiology , Bacterial Toxins/analysis , Bacteroides fragilis/isolation & purification , Bacteroides fragilis/metabolism , Coinfection , Candida albicans/isolation & purification , Candidiasis, Vulvovaginal/microbiology , Exudates and Transudates/microbiology , Gardnerella vaginalis/isolation & purification , Metalloendopeptidases/analysis , Mycoplasma Infections/microbiology , Mycoplasma hominis/isolation & purification , Staphylococcal Infections/microbiology , Vagina/microbiologyABSTRACT
The presence of enterotoxigenic Bacteroides fragilis and nontoxigenic B. fragilis (NTBF) among 109 strains isolated from 1980-2008 in Brazil were investigated by PCR. One strain, representing 0.9 percent of the total analyzed strains, harbored the bft gene which was identified as bft-1 isoform based on PCR-RFLP and sequencing. Forty-nine strains (44.9 percent) exhibited the NTBF pattern III which possesses the flanking region required for pathogenicity island acquisition in which the bftgene is codified. These data reinforce the potential of B. fragilis as an emerging enteropathogen in our country.
Subject(s)
Humans , Bacteroides fragilis/genetics , Enterotoxins/biosynthesis , Genes, Bacterial/genetics , Brazil , Bacteroides fragilis/classification , Bacteroides fragilis/pathogenicity , Polymerase Chain Reaction , Polymorphism, Restriction Fragment LengthABSTRACT
La vaginitis es un diagnóstico común en ginecología. Su presencia obedece a diversas causas, algunas aún desconocidas. Bacteroides fragilis es el anaerobio más importante desde el punto de vista clínico. Entre otros factores de virulencia, algunas cepas producen una enterotoxina asociada con diarrea. Estas cepas han sido aisladas tanto de muestras intestinales como extra intestinales. Por la existencia de procesos inflamatorios en la mucosa cérvico-vaginal de etiología desconocida se investiga a B. fragilis enterotoxigénico en pacientes con vaginitis. Se procesaron 140 muestras de pacientes y 40 de controles sanos. De las pacientes sintomáticas se aislaron 15 cepas de B. fragilis y ninguna en los controles (P<0,05). Posteriormente, fueron cultivadas en anaerobiosis, usando caldo cerebro-corazón suplementado con vitamina K1 y hemina durante 48 horas a 36°C. El sobrenadante se obtuvo por centrifugación y su actividad se ensayó en células HT-29. Doce (80%) cepas produjeron alteraciones en la monocapa celular, manifestada por desprendimiento, disolución de los acúmulos, expansión y disgregación de las células, superando en algunos casos la toxicidad observada en el control positivo. En siete pacientes, B. fragilis enterotoxigénico no estuvo asociado a patógenos específicos. La presencia de B. fragilis enterotoxigénico en pacientes con vaginitis plantea la necesidad de definir su papel en la etiología de esta entidad clínica.
Vaginitis is a common diagnosis in the centers of gynecological attention. It is due to several causes, some even unknown. Bacteroides fragilis is the most important anaerobe in clinical practice; some strains produce an enterotoxin associated with diarrhea. Enterotoxigenic B. fragilis has been isolated from intestinal as well as extra intestinal samples. Because inflammatory processes unknown etiology it was investigated B. fragilis in the cervical-vaginal mucous in the patients with vaginitis. 140 samples were processed from symptomatic patients and 40 from healthy controls. 15 strains of B. fragilis were isolated from symptomatic patients while none were found in controls (P<0,05). These strains were cultivated in anaerobic chambers, cultured in brain heart infusion supplemented with vitamin K1 and hemine during 48 hours at 36°C. Supernatant were obtained by centrifugation and its activity assayed in HT-29 cells. Twelve (80%) of the isolated induced alterations in target cell morphology characterized by cell detachment, breakup of cell clumps, expansion and degradation of cells, some cases revealed a higher cytotoxic activity than the positive control. In seven patients enterotoxigenic B. fragilis was not associated to specific pathogens. The presence of enterotoxigenic B. fragilis in patients with vaginitis raises the necessity to define its role in the etiology of this clinical entity.