CASE SUMMARY• 20 yrs old male ,nonsmoker, normotensive, euglycemic presented with

• Chief c/o : Acute onset of dyspnea and cough with scanty sputum production X 2 d

• No H/o fever but however h/o wheezing and chest tightness is present.

• No H/o PND, chest pain, hemoptysis

CASE SUMMARY• Symptoms appeared after he went to visit his friend ,while playing with his dog.

• Similar episodes was present 1 year back. Running nose ,sneezing and rashes were accompanied features.

• Family history present .

• Patient became asymptomatic after use of some inhalers.

Pratap Sagar Tiwari

MD, Lecturer, NMC

AN INTRODUCTION TO ASTHMA

DEFINITION• Asthma is a syndrome characterized by airflow limitation/obstruction that varies

markedly , both spontaneously and with treatment.

• There is a hyperresponsiveness to a wide range of triggers leading to excessive narrowing with consequent decrease in airflow and symptomatic wheezing and dyspnea.

• Note: Airway hyper-reactivity (AHR)-the tendency for airways to contract too easily and too much in response to triggers that have little or no effect in normal individuals. Reference: Davidson

• The "classic" signs and symptoms of asthma are intermittent dyspnea, cough, and wheezing.

ETIOLOGY/TRIGGERS/RISK FACTORS• Atopy

• Hygiene hypothesis

• Infections

• Genetics: ADAM33, GPRA

• Occupational: bakers and chemical factory

• Diet: vit a/c/d def, Mg/Se def, obesity

• Hormonal: premenstrual period, thyroidal illness

ATOPYIt is the genetic predisposition to develop specific IgE antibodies directed against environmental allergies.

It is the strongest identifiable risk factor for asthma.

Trigger includes pollen, fungal spores, food containing nuts, air pollution, cold air, laughter, perfumes etc.

HYGIENE HYPOTHESIS• Lower level of infection in childhood may be a factor related to increase risk of asthma.

• The HH proposes that lack of infection in early childhood preserves the TH2 bias.

• Exposure to infection result in shift towards predominant protective Th1 immune response.

INFECTIONS• Viral: rhinovirus, corona virus, RSV

• Bacterial: mycoplasma, chlamydia etc

ETIOLOGY/TRIGGERS/RISK FACTORSOther risk factor includes,

• Low birth weight, prematurity, low maternal age

Other trigger includes b blockers, ACE inhibitors

Others: Exercise, Acid reflux, Stress

Note:

ACE inhibitors inhibits degradation of Bradykinin Increase bradykinin Vasodilation, bronchoconstriction and increase vascular permeability.

B blockers bronchospasms

PATHOPHYSIOLOGY • Airway inflammation

• Airway obstruction

• Bronchial hyperresponsiveness

MAKING A DIAGNOSIS• Compatible clinical features

• Precipitating factors

• Family history

• Reversibility of symptoms/response to bronchodilators

ASTHMA VS COPD Asthma

• -- Not always productive cough

• -- Usually reversible

• -- Often associated with allergies

• -- Cough at night and early mornings

• -Family history

• --Variability

COPD

• -- Cough is usually productive

• -- Symptoms not reversible

• -- Common history of smoking

• -- Cough in morning and throughout the day.

• -- Age

Note: The diagnosis of asthma is predominantly clinical and based on a characteristic history.A trial of corticosteroids: e.g. 30 mg daily for 2 weeks

Ref: GINA guidelinePic taken from: http://upload.wikimedia.org/wikipedia/commons/f/f7/Peak_flow_meter_horiz.jpg

ASSESSMENT OF SEVERITY

DRUGS USED IN ASTHMAController Reliever

ICS :GlucocorticosteroidsBeclomethasone/ budesonide/ fluticasone

SAB2A: Salbutamol/ Levalbuterol/ Terbutaline /Pirbuterol

LAB2A: Salmeterol/ formeterol Anticholinergics: Ipratropium /Oxitropium B

Antileukotrienes: montelukast/ zafirlukast Short acting Theophylline: Aminophylline

Cromones: Cromolyn /nedocromil sodium Epineprine/Adrenaline

Anti-IgE: Omalizumab

Controller medication: taken daily to prevent symptoms, improve lung function and prevent attacks.Reliever: Occasionally required to treat acute symptoms such as wheezing, chest tightness and cough.

TREATMENT STRATEGY

1 2 3 4 5

Leukotriene modifier Anti IgE

Theophylline SR

LEVEL OF ASTHMA CONTROL

Notes:

• COPD affects both the airways and the parenchyma, whilst asthma affects only the airways.

• The nature of inflammation in Asthma is primarily eosinophilic and CD4-driven .In COPD it is neutrophilic and CD8-driven .

• For asthma, severity is based on symptom frequency and severity, lung function but for COPD, the stages of severity are defined by lung function.

• Homework: Management of Acute severe Asthma

References:

• Harrison 18th ed .

• Davidsons.

• Uptodate 19.2

• GINA guidelines