Page 87 - Škrgat, Sabina, ed. 2022. Severe Asthma - Basic and Clinical Views. Koper: University of Primorska Press. Severe Asthma Forum, 1
P. 87
her proportion of neutrophils in their spu- is no perfect endotype classification. Multiple 87
tum than ex-smokers or never smokers30. In- biomarkers are superior to a single biomark-
dependent predictors of sputum eosinophil er. Despite significant improvement in asthma biomarkers in severe asthma
count ≥3% were the percentage of blood eo- understanding, there is still a long way to go
sinophils, low FEV1/FVC, and high FENO to resolve the asthma problem in most persons
and IgE levels. A cut-off value of 220/mm3 suffering from asthma syndrome.
or 3% for blood eosinophils performed equal-
ly to FeNO50 ppb to identify the presence of References
a sputum eosinophil count ≥3%. Independent
predictors of sputum neutrophilia were ad- 1. Soriano JB, Abajobir AA, Abate KH,
vanced age and high FRC, while blood neu- et al. Global, regional, and nation-
trophil count was not31. Sputum eosinophils al deaths, prevalence, disability-adjust-
>3% can only distinguish eosinophilic vs neu- ed life years, and years lived with disa-
trophilic, mixed or paucigranulocytes asthma bility for chronic obstructive pulmonary
phenotype33. Using blood eosinophilia per se disease and asthma, 1990-2015: a sys-
as a biomarker for eosinophilic asthma is dif- tematic analysis for the Global Burden
ficult due to the daily fluctuations of blood eo- of Disease Study 2015. Lancet Respir
sinophils, with or without treatment34. In the Med. 2017 Sep;5(9):691-706.
study by Agache et al., serum IL-5 and IL-13
were identified as the best blood eosinophilia 2. Lambrecht BN, Hammad H. The im-
predictors, with a good reproducibility at re- munology of asthma. Nat Immunol.
peated testing after 6 weeks34. 2015 Jan;16(1):45-56.
Conclusion 3. Reddel HK, Bateman ED, Becker A, et
al. A summary of the new GINA strat-
Asthma is a complex heterogeneous condi- egy: a roadmap to asthma control. Eur
tion, and under this broad term, severe asth- Respir J. 2015 Sep;46(3):622-39.
ma itself covers several subgroups with spe-
cific characteristics, symptom profiles and 4. Fajt ML, Wenzel SE. Asthma phe-
biochemical mechanisms of the disease. A notypes and the use of biologic med-
biomarker is objectively measured and eval- ications in asthma and allergic dis-
uated as an indicator of normal biological ease: the next steps toward personal-
processes, pathogenic processes, or pharma- ized care. J Allergy Clin Immunol. 2015
cologic responses to a therapeutic interven- Feb;135(2):299-310; quiz 311.
tion. In severe asthma, biomarkers could be
used for diagnosis of phenotype or endotype, 5. Chung KF. Precision medicine in asth-
can also be predictive of clinical outcomes ma: linking phenotypes to targeted
or response to therapy, and may be dynamic treatments. Curr Opin Pulm Med. 2018
with time or therapy. Fully determining phe- Jan;24(1):4-10.
notype or endotype of severe asthma will re-
quire the interpretation of combinations of 6. Rackemann FM. A working classi-
commercially available biomarkers. Today, fication of asthma. Am J Med. 1947
defining a severe asthma endotype is a pro- Nov;3(5):601-6.
cess based on a biomarker-driven approach.
There is no perfect biomarker. Biomarkers for 7. Greening AP, Ind PW, Northfield M,
asthma are less precise, and still not complete- et al. Added salmeterol versus high-
ly known. With no perfect biomarkers, there er-dose corticosteroid in asthma patients
with symptoms on existing inhaled cor-
ticosteroid. Allen & Hanburys Limit-
ed UK Study Group. Lancet. 1994 Jul
23;344(8917):219-24.
8. A plea to abandon asthma as a dis-
ease concept. Lancet. 2006 Aug
tum than ex-smokers or never smokers30. In- biomarkers are superior to a single biomark-
dependent predictors of sputum eosinophil er. Despite significant improvement in asthma biomarkers in severe asthma
count ≥3% were the percentage of blood eo- understanding, there is still a long way to go
sinophils, low FEV1/FVC, and high FENO to resolve the asthma problem in most persons
and IgE levels. A cut-off value of 220/mm3 suffering from asthma syndrome.
or 3% for blood eosinophils performed equal-
ly to FeNO50 ppb to identify the presence of References
a sputum eosinophil count ≥3%. Independent
predictors of sputum neutrophilia were ad- 1. Soriano JB, Abajobir AA, Abate KH,
vanced age and high FRC, while blood neu- et al. Global, regional, and nation-
trophil count was not31. Sputum eosinophils al deaths, prevalence, disability-adjust-
>3% can only distinguish eosinophilic vs neu- ed life years, and years lived with disa-
trophilic, mixed or paucigranulocytes asthma bility for chronic obstructive pulmonary
phenotype33. Using blood eosinophilia per se disease and asthma, 1990-2015: a sys-
as a biomarker for eosinophilic asthma is dif- tematic analysis for the Global Burden
ficult due to the daily fluctuations of blood eo- of Disease Study 2015. Lancet Respir
sinophils, with or without treatment34. In the Med. 2017 Sep;5(9):691-706.
study by Agache et al., serum IL-5 and IL-13
were identified as the best blood eosinophilia 2. Lambrecht BN, Hammad H. The im-
predictors, with a good reproducibility at re- munology of asthma. Nat Immunol.
peated testing after 6 weeks34. 2015 Jan;16(1):45-56.
Conclusion 3. Reddel HK, Bateman ED, Becker A, et
al. A summary of the new GINA strat-
Asthma is a complex heterogeneous condi- egy: a roadmap to asthma control. Eur
tion, and under this broad term, severe asth- Respir J. 2015 Sep;46(3):622-39.
ma itself covers several subgroups with spe-
cific characteristics, symptom profiles and 4. Fajt ML, Wenzel SE. Asthma phe-
biochemical mechanisms of the disease. A notypes and the use of biologic med-
biomarker is objectively measured and eval- ications in asthma and allergic dis-
uated as an indicator of normal biological ease: the next steps toward personal-
processes, pathogenic processes, or pharma- ized care. J Allergy Clin Immunol. 2015
cologic responses to a therapeutic interven- Feb;135(2):299-310; quiz 311.
tion. In severe asthma, biomarkers could be
used for diagnosis of phenotype or endotype, 5. Chung KF. Precision medicine in asth-
can also be predictive of clinical outcomes ma: linking phenotypes to targeted
or response to therapy, and may be dynamic treatments. Curr Opin Pulm Med. 2018
with time or therapy. Fully determining phe- Jan;24(1):4-10.
notype or endotype of severe asthma will re-
quire the interpretation of combinations of 6. Rackemann FM. A working classi-
commercially available biomarkers. Today, fication of asthma. Am J Med. 1947
defining a severe asthma endotype is a pro- Nov;3(5):601-6.
cess based on a biomarker-driven approach.
There is no perfect biomarker. Biomarkers for 7. Greening AP, Ind PW, Northfield M,
asthma are less precise, and still not complete- et al. Added salmeterol versus high-
ly known. With no perfect biomarkers, there er-dose corticosteroid in asthma patients
with symptoms on existing inhaled cor-
ticosteroid. Allen & Hanburys Limit-
ed UK Study Group. Lancet. 1994 Jul
23;344(8917):219-24.
8. A plea to abandon asthma as a dis-
ease concept. Lancet. 2006 Aug
