title: Severe asthma: definition, diagnosis and treatment.
abstract: BACKGROUND
  A minority of patients with asthma have uncontrolled or partially controlled asthma despite intensive treatment. These patients present a special challenge because of the extensive diagnostic evaluation that they need, insufficient evidence regarding personalized treatments, and their high consumption of health-care resources.
  
  
  METHODS
  The definition, diagnosis, and treatment of severe asthma are presented on the basis of a selective literature review and the authors' clinical experience.
  
  
  RESULTS
  Severe asthma is present, by definition, when adequate control of asthma cannot be achieved by high-dose treatment with inhaled cortico - steroids and additional controllers (long-acting inhaled beta 2 agonists, montelukast, and/or theophylline) or by oral corticosteroid treatment (for at least six months per year), or is lost when the treatment is reduced. Before any further treatments are evaluated, differential diagnoses of asthma should be ruled out, comorbidities should be treated, persistent triggers should be eliminated, and patient adherence should be optimized. Moreover, pulmonary rehabilitation is recommended in order to stabilize asthma over the long term and reduce absences from school or work. The additional drugs that can be used include tiotropium, omalizumab (for IgE-mediated asthma), and azithromycin (for non-eosinophilic asthma). Antibodies against interleukin-5 or its receptor will probably be approved soon for the treatment of severe eosinophilic asthma.
  
  
  CONCLUSIONS
  The diagnosis and treatment of severe asthma is time consuming and requires special experience. There is a need for competent treatment centers, continuing medical education, and research on the prevalence of severe asthma.
authors.affiliation: Department of Pneumology/Interdisciplinary Intensive Care Unit, University of Rostock.
authors.forename: Marek
authors.initials: M
authors.lastname: Lommatzsch
authors.forename: J Christian
authors.initials: JC
authors.lastname: Virchow
mesh_terms: D000280:Administration, Inhalation; D018927:Anti-Asthmatic Agents / Q000008:administration & dosage*; D001249:Asthma / Q000145:classification / Q000175:diagnosis* / Q000628:therapy*; D003952:Diagnostic Imaging / Q000379:methods; D006801:Humans; D008487:Medical History Taking / Q000379:methods; D018727:Muscarinic Antagonists / Q000008:administration & dosage*; D010808:Physical Examination / Q000379:methods*; D012129:Respiratory Function Tests / Q000379:methods*; D012720:Severity of Illness Index; D009626:Terminology as Topic
chemical_list: D018927:Anti-Asthmatic Agents; D018727:Muscarinic Antagonists