Clinical Features of Asthma in Children Flashcards
what are the challenges of dealing with asthma?
- No definition
- No tests
- Two national guidelines
- Symptom based
- Identical to LRTI symptoms (cough, SOB, noisy breathing)
- Relapse and remission
Tips to dealing with asthma:
- No _________, no asthma
- Tests ___ help decision
- If…..
QoL affected, confirm the diagnosis with trial of ___ (to confirm diagnosis)
QoL not affected (by symptoms), _____ ___ ___
wheeze
may
ICS
watch and see
If child doesn’t wheeze then they don’t have ______
asthma
What is asthma?
- Literally “panting”
- Chronic
- Wheeze, cough and SOB
- Multiple triggers
- Variable/reversible
- Responds to asthma Rx
what 3 things msut you have to have asthma?
•Wheeze, cough and SOB
for asthma you have to have a ________, it has to _______ to treatment and it has to be _______
wheeze
respond
variable
No longer a diagnosis of _________
exclusion
what are the 3 Key words in relation to asthma?
- Wheeze
- Variability
- Respond to treatment
What causes asthma?
No one really knows what causes it
What we know:
- Host response to environment
- Infection important
- Physiology abnormal before symptoms
- It is a syndrome
Many inconsistencies in asthma such as what?
- “Transient” vs persistent (symptoms)
- VIW versus asthma/MTW (multi trigger wheeze)
- Different severities
- Different age at onset
- Heterogeneity in response
- Different triggers
- How can a single condition do this???
Asthma syndromes - can occur in many setting
example picture shown
What causes asthma? - how are genes involved?
- Genes - 30-80% of causation
- ~10 variants making modest contribution
- ADAM33, ORMDL3 (People with these genes don’t all have asthma)
- Interact with environment (If predisposed to asthma, its only when you encounter environment when you get asthma symptoms)
- Epigenetics (the study of changes in organisms caused by modification of gene expression rather than alteration of the genetic code itself)
does allergy cause asthma? - probably not
so what expalines the link between allergy and asthma?
•Primary epithelial abnormality (skin/airway/gut) results in:
- Eczema/asthma/etc
- Allergy
•Allergy then fuels eczema/asthma/etc
Allergic sensitisation fuels the symptoms in the affected organ (skin, lung, gut)
what is the epidemiology of asthma?
a very British problem - Burden of asthma in UK is highest in world (prob same now a days)
- 1.1 million UK children
- 110, 000 in Scotland
- 5% of UK children on inhaled steroids!
Asthma “epidemic” probably over
So why the rise and fall?
Westernisation! - what is it to do with asthma?
Burden of asthma/eczema/hay fever is higher on the western side of these geographically very closely placed areas, these areas where genetic diversity is very limited/very similar so only reason to explain these 2 is lifestyle and/or diagnostic threshold
Western lifestyle is associated with an increased risk of asthma and probably in the first 3 years this is having an influence
- Retained if move >3 yo
- Acquire “Western” risk if born there
what is Proof of causation?
Two RCTs proven causation
Offspring at risk for asthma
Complex
- Feeding - Breast, Late weaning
- Allergen (reduced exposure) - Ante- and post-natal
- Smoking (parents stop)
What happens in _____ life, often before we are born, is a really important ___________ of our later respiratory life course
early
determinant
if they do have asthma like symptoms affecting their QoL then what do you do?
give them a trial of inhaled steroids as a diagnostic test
So when is it asthma? - how do you make the diagnosis?
- All in the history!
- Examination unhelpful - Unlikely to be wheezing, Stethoscope never important (often unhelpful)
- No diagnostic asthma test in children:
- Peak flow random number generator
- Allergy tests irrelevant (Majority of people with allergy don’t have asthma and 25% of people with asthma don’t have allergy)
- Spirometry lacks specificity
- Exhaled nitric oxide unproven
•Tests can be useful (excluding > diagnosing)
how may spirometry be done to be useful?
do it
then make them take a BDR (bronchodilator response)
then repeat and see if it has changed
Asthma diagnosis - NICE
- Spirometry
- BDR
- FeNO
- Peak flow
Asthma diagnosis – BTS/SIGN
- Spirometry
- BDR
- FeNO
- Peak flow
what is the problem with asthma in paediatrics?
- Uncertainty greatest in <5s
- Tests not reliable in <5s
- Tests not great anyway
how is a wheeze present in asthma?
- A “must have”
- But not in isolation
- Cough variant asthma does not exist (in children)
- Cough predominant asthma not uncommon
