title: Serum eosinophil cationic protein is superior to mast cell tryptase as marker for response to topical corticosteroid therapy in eosinophilic esophagitis.
abstract: OBJECTIVE
  We evaluated the serum levels of eosinophil cationic protein (ECP) and mast cell tryptase (MCT) as surrogate markers for response to treatment in adults with eosinophilic esophagitis (EoE) under topical steroid therapy with fluticasone.
  
  
  BACKGROUND
  EoE is a chronic disease characterized histologically by eosinophilic inflammation of the esophagus. Esophageal mastocytosis and mast cell activation have been implicated in EoE pathogenesis.
  
  
  METHODS
  Fifteen patients with EoE completed this prospective observational study. Before and after 3 months of therapy with fluticasone, eosinophilic and mast cell counts were analyzed from histologic samples of the esophagus and were correlated with serum markers ECP and MCT.
  
  
  RESULTS
  Fluticasone-therapy significantly decreased mean eosinophils [from 42.2 to 16.2 eosinophils/high-power field (hpf); P=0.004] and mast cells (from 13.9 to 5.1 mast cells/hpf; P=0.001) in the esophageal epithelium. There was a significant decrease of mean ECP (from 15.6 to 5.5 μg/L; P=0.024) and MCT-serum-values (from 4.7 to 3.8 μg/L; P=0.029) under therapy. Serum-ECP correlated significantly with histologic eosinophilic counts after fluticasone-therapy (r=0.54; P=0.038) in contrast to serum-MCT.
  
  
  CONCLUSIONS
  Serum-ECP but not serum-MCT could be a promising noninvasive biomarker to assess response to topical corticosteroid therapy in EoE. These findings should be confirmed by larger studies; ClincialTrials.gov number, NCT01624129.
authors.affiliation: *II. Medizinische Klinik §Institut für Pathologie, Klinikum rechts der Isar der †Klinik für Dermatologie und Allergologie am Biederstein ‡Institut für Medizinische Statistik und Epidemiologie, TU München, München, Germany.
authors.forename: Christoph
authors.initials: C
authors.lastname: Schlag
authors.forename: Sabrina
authors.initials: S
authors.lastname: Pfefferkorn
authors.forename: Knut
authors.initials: K
authors.lastname: Brockow
authors.forename: Bernhard
authors.initials: B
authors.lastname: Haller
authors.forename: Julia
authors.initials: J
authors.lastname: Slotta-Huspenia
authors.forename: Stephan
authors.initials: S
authors.lastname: Schulz
authors.forename: Alexander
authors.initials: A
authors.lastname: von Werder
authors.forename: Johannes
authors.initials: J
authors.lastname: Ring
authors.forename: Roland M
authors.initials: RM
authors.lastname: Schmid
authors.forename: Monther
authors.initials: M
authors.lastname: Bajbouj
mesh_terms: D000287:Administration, Topical; D000328:Adult; D000730:Androstadienes / Q000008:administration & dosage / Q000627:therapeutic use*; D000893:Anti-Inflammatory Agents / Q000008:administration & dosage / Q000627:therapeutic use*; D015415:Biomarkers / Q000097:blood; D047150:Eosinophil Cationic Protein / Q000097:blood*; D057765:Eosinophilic Esophagitis / Q000097:blood* / Q000188:drug therapy* / Q000473:pathology; D004804:Eosinophils; D005260:Female; D000068298:Fluticasone; D006801:Humans; D007958:Leukocyte Count; D008297:Male; D008875:Middle Aged; D011446:Prospective Studies; D053802:Tryptases / Q000097:blood*; D055815:Young Adult
chemical_list: D000730:Androstadienes; D000893:Anti-Inflammatory Agents; D015415:Biomarkers; D000068298:Fluticasone; D047150:Eosinophil Cationic Protein; D053802:Tryptases