title: Outcome of prophylactic therapy for idiopathic anaphylaxis.
abstract: OBJECTIVE
  To determine the efficacy of a prophylactic regimen (prednisone, H1 blockade, and sympathomimetic amine therapy) in patients with idiopathic anaphylaxis.
  
  
  METHODS
  Clinical trial before and after treatment.
  
  
  METHODS
  Referral-based allergy clinic at a major medical center.
  
  
  METHODS
  Fifty-three patients with a history compatible with idiopathic anaphylaxis for at least 6 months before presentation to the allergy service and with subsequent management by the service for at least 6 months.
  
  
  METHODS
  Patients with frequent life-threatening symptoms were treated with a prophylactic regimen. Patients with infrequent episodes of idiopathic anaphylaxis were only treated acutely for each episode of anaphylaxis.
  
  
  RESULTS
  The results favored prophylactic treatment with prednisone for patients who were classified as generalized-frequent in the clinical outcome measures of frequency (per patient per year) of episodes (mean before treatment, 7.31 +/- 6.46; after treatment, 3.61 +/- 4.73; P less than 0.02) and emergency room visits (mean before treatment, 1.94 +/- 3.42; after treatment, 0.21 +/- 0.44; P less than 0.005) and for patients classified as angioedema-frequent in the frequency of episodes (mean before treatment, 14.93 +/- 15.89; after treatment, 2.58 +/- 2.18; P less than 0.003) and emergency room visits (mean before treatment, 0.76 +/- 1.01; after treatment, 0.07 +/- 0.11; P less than 0.025). No statistically significant difference was found for patients classified as generalized-infrequent in the frequency of episodes (mean before treatment, 2.01 +/- 1.30; after treatment, 1.36 +/- 1.79) or of the emergency room visits (mean before treatment, 0.56 +/- 0.71; after treatment, 0.32 +/- 0.75) or for patients classified as angioedema-infrequent in the frequency of episodes (mean before treatment, 1.94 +/- 1.55; after treatment, 2.03 +/- 2.16) or of emergency room visits (mean before treatment, 0.27 +/- 0.44; after treatment, 0.37 +/- 0.59).
  
  
  CONCLUSIONS
  Prophylactic treatment with prednisone and H1 antihistamines with or without sympathomimetic amines improves clinical outcome in patients who are classified as idiopathic anaphylaxis-angioedema frequent and idiopathic anaphylaxis-generalized frequent.
authors.affiliation: Northwestern University Medical School, Chicago, Illinois.
authors.forename: S
authors.initials: S
authors.lastname: Wong
authors.forename: P R
authors.initials: PR
authors.lastname: Yarnold
authors.forename: C
authors.initials: C
authors.lastname: Yango
authors.forename: R
authors.initials: R
authors.lastname: Patterson
authors.forename: K E
authors.initials: KE
authors.lastname: Harris
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000707:Anaphylaxis / Q000145:classification / Q000150:complications / Q000517:prevention & control*; D000799:Angioedema / Q000209:etiology / Q000517:prevention & control; D002648:Child; D002985:Clinical Protocols; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D010043:Outcome and Process Assessment, Health Care; D011241:Prednisone / Q000627:therapeutic use*; D012074:Remission Induction; D013223:Statistics as Topic
chemical_list: D011241:Prednisone