This lecture is on Pathology of asthma for nurses. This lecture is prepared for sem 4 nursing students. It includes, etiopathogenesis, gross morphology and microscopic morphology and diagnosis of asthma. It describes charcot leyden crystals and Cruschman spiral.

1. ASTHMA - PATHOLOGY
BY : MS. SAILI GAUDE
PRINCIPAL
SHIVAM COLLEGE OF NURSING

2. DEFINITION
Disease of airways that is characterized by increased
responsiveness of the tracheobronchial tree to a variety of stimulus
leading to spasmodic narrowing of the air passage.

3. ETIOPATHOGENESIS & TYPES
EXTRINSIC INTRINSIC

4. EXTRINSIC ASTHMA
Also called allergic asthma
Begins in childhood
Family history present of allergic diseases
Hypersensitivity to allergens
Allergens like, dust, pollens, animal danders etc.
Occupational asthma is a variant of extrinsic asthma in
which fumes, gases and organc substances inhaled by
the person causes asthma.
Increased levels og Ig E in serum
Positive skin tests for allegerns

5. ASTHMA TRIGGERS
Allergens
Pharmacologic agents
Physical triggers like exercise, cold air
Physiological factors- Stress, GERD, Viral and bacterial infections
Strong smells
Strong emotions like crying, anger

6. Occurs by Ig E mediated hypersensitivity reaction occurring in 2 stages
Acute immediate response Late phase reaction

7. 1) ACUTE IMMEDIATE RESPONSE
Initiated by Ig E sensitized mast cells
Mast cells on degranulation releases cell mediators like
histamine, prostaglandins, leukotrienes etc.
Bronchoconstriction occurs due to inflammatory reaction
Oedema
Hypersecretion of the mucus occurs
Eosinophils and neutrophils accumulates

8. 2) LATE PHASE REACTIONS
Follows acute immediate response.
Responsible for prolonged effect of asthma
Excessive mobilization of blood leucocytes including
basophils leads to release of further cell mediators
thus taking time to heal.
Inflammatory injury occurs.

9. INTRINSIC ASTHMA
Also called idiosyncratic or non atopic asthma
No family history of asthma
No known allergens
Negative skin tests for allergens
Normal serum IgE levels
Usually occurs in adults
Occurs after a upper respiratory tract infection caused
by a virus
Patient becomes hypersensitive to drugs.
Aspirin sensitive asthma

10. ASPIRIN INDUCED ASTHMA
Induced by ingestion of aspirin
Triad- combination of aspirin, nasal polyp and sinusitis

11. MIXED ASTHMA
Patient does not clearly fits into any classification
Asthma which occurs as a result of cold, exercise, emotional stress etc falls under this category

12. EXERCISE INDUCED ASTHMA
Occurs 5 to 20 min of exercise
Slight chest pain to severe cough and wheezing may occur
Shortness of breath

13. GROSS MORPHOLOGY
Overdistended lungs
Overinflation
Cut surface- obstructed bronchioles and bronchi
Thick Mucus plugs

14. MICROSCOPIC MORPHOLOGY
Mucus plugs contains normal or degenerated respiratory epithelium
This twists into spirals called as the CRUSHMAN’S SPIRALS
Sputum contains eosinophils
Diamond shaped crystals derived from eosinophils are also seen in sputum called as the CHARCOT-
LEYDEN CRYSTALS
Thick wall of the bronchi
Submucosal edema
Inflammatory infiltrate of lymphocytes, plasma cells and eosinophils
Too much eosinophils
Hypertrophy of mucosal glands
Hypertrophy of smooth muscles of the bronchi

16. Epithelial shedding
Exudative inflammatory process and sloughing of epithelial cells into the airway impairs
mucociliary transport
Bronchial glands increases in size and number

17. CLINICAL FEATURES
Acute attacks with symptom free periods
Attacks of dyspnea
Cough
Wheezing
Lasts from minutes to hours
Use of accessory muscles
Tachypnea
Tachycardia
Hyperesonance

18. Diaphoresis
Restlessnesa
Pallor
Physical exhaustion

19. STATUS ASTHMATICUS
Life threatening emergency
Occurs when bronchospasms does not get relived by conventional medications
Can lead to worsening of acid base balance, hypoxemia respiratory arrest etc.

20. Diagnostic studies
History and physical examination
Pulmonary function test
Chest x ray
Arterial blood gas
Oximetry
Allergy testing
Blood levels of eosinophils
Sputum culture and sensitivity
Spirometry – Patient demonstrates lung capacity by blowing air into the incentive spirometer
Methacholine challenge- patient breathes in increasingbamounts of methacholine andperforms
spirometry after each dose.

21. TREATMENT
Long term control medications
1) Corticosteroids
Inhaled form
Systemic steroids
2)Cromolyn sodium
Anti inflammatory agents
3)Long acting beta blockers- relaxes airway smooth muscles
4)Methylxanthines- bronchodilator
5)Leukotrine modifiers- reduces leukotriene

22. QUICK RELIEF MEDICATIOSN
1) Short acting beta 2 antagonists- relaxes airway smooth muscles and increase in airflow
2) Anticholinergics- bronchodilator
3) Systemic steroids