title: Patients with endometriosis of the rectosigmoid have a higher percentage of natural killer cells in peripheral blood.
abstract: OBJECTIVE
  To estimate the concentration of natural killer (NK) cells in the peripheral blood in patients with and without endometriosis.
  
  
  METHODS
  Case-control study (Canadian Task Force classification II-2).
  
  
  METHODS
  Tertiary referral hospital.
  
  
  METHODS
  One hundred fifty-five patients who had undergone videolaparoscopy were divided into 2 groups: those with endometriosis (n = 100) and those without endometriosis (n = 55).
  
  
  METHODS
  The percentage of NK cells relative to peripheral lymphocytes was quantified at flow cytometry in 155 patients who had undergone laparoscopy. In addition to verifying the presence of endometriosis, stage of disease and the sites affected were also evaluated.
  
  
  RESULTS
  The mean (SD) percentage of NK cells was higher (15.3% [9.8%]) in patients with endometriosis than in the group without the disease (10.6% [5.8%]) (p < .001). The percentage of NK cells was highest (19.8 [10.3%]) in patients with advanced stages of endometriosis and in those in whom the rectosigmoid colon was affected. In a statistical model of probability, the association of this marker (NK cells ≥11%) with the presence of symptoms such as pain and intestinal bleeding during menstruation and the absence of previous pregnancy yielded a 78% likelihood of the rectosigmoid colon being affected.
  
  
  CONCLUSIONS
  Compared with patients without endometriosis, those with endometriosis demonstrate a higher concentration of peripheral NK cells. The percentage of NK cells is greater, primarily in patients with advanced stages of endometriosis involving the rectosigmoid colon. Therefore, it may serve as a diagnostic marker for this type of severe endometriosis, in particular if considered in conjunction with the symptoms.
authors.affiliation: Department of Obstetrics and Gynecology, São Paulo University, São Paulo, Brazil. jadiasjr@me.com
authors.forename: João Antonio
authors.initials: JA
authors.lastname: Dias
authors.forename: Sérgio
authors.initials: S
authors.lastname: Podgaec
authors.forename: Ricardo Manoel
authors.initials: RM
authors.lastname: de Oliveira
authors.forename: Maria Lucia
authors.initials: ML
authors.lastname: Carnevale Marin
authors.forename: Edmund Chadad
authors.initials: EC
authors.lastname: Baracat
authors.forename: Mauricio Simões
authors.initials: MS
authors.lastname: Abrão
mesh_terms: D000328:Adult; D016022:Case-Control Studies; D004715:Endometriosis / Q000097:blood* / Q000473:pathology; D005260:Female; D006801:Humans; D007694:Killer Cells, Natural / Q000473:pathology*; D018655:Lymphocyte Count; D012810:Sigmoid Diseases / Q000097:blood* / Q000473:pathology