patho sheet #21 - Yasmin Nofal

Last lecture we started to talk about the obstructive lung disease they include: emphysema, chronic bronchitis, asthma and bronchiectasis.
Emphysema is abnormal permanent enlargement of the airway distal to the terminal bronchilos,assiciated with destruction of the alveoli septa without fibrousis of these septa.
Types: 1. Centriacinar :- affect respiratory bronchioles without affection of the alveoli and alveolar duct.
2. Panacinar:- affect ? From the respiratory bronchiole to the alveoli.
-the most common type is the centriacinar caused by cigarette smoking.
-panacinar caused by alpha 1 antitrypsin defiecency,associated with chronic bronchitis COPD.
3. Distalacinar (paraceptal) :- the proximal portion of the distal airway is not affected, there is affection of the alveolar duct and the alveoli, so distal acinar doesn't affect the respiratory bronchioles.
In anatomy, there is connective tissue septa between lobules of the lung, the paraceptal usually located adjacent to these septa and adjacent to the pleura.
-the upper half of the lung is more affected than the lower half.
-adjacent to areas of fibrosis,sarring or atelectasis but the fibrosis doesn’t reach the septa.
-enlargement of air spaces (cyst like structure) ranges from 0.5 mm – 2 cm,,,,if its more than 1 cm it becomes bullae,becz the bullae are adjacent to the pleura, rupture of these bulleu cause escape of the air into pleura and cause spontaneous pneumothorax in young adults (which is the main cause).
4. Irregular emphysema :- the acinus is irregularly involved, some acinar involved in the proximal part and some of them involved in the distal part, adjacent to areas of scarring, and its asymptomatic
Morphology of emphysema : diagnosis and classification depend on macroscopic appearance of the lung.
Panacinar:- involve the whole acinus from the respiratory bronchiole to the alveoli, the lung will be large, voluminous and obscure the heart, involve lower half of the lung.
Centriacinar:- the enlargement is less voluminous than the panacinar,it involves the upper half of the lung.
Histological :- thinning and destruction of the alveolar walls without fibrosis of these walls.
-alveolar wall contain interstitial, lung contain elastic tissue maintain the airway open during expiration , loss of elastic tissue,,,,air way will collapse during expiration.
On microscopic examination : enlargement of air spaces and destruction of the alveoli septa.
Clinical course: the most important symptoms in patient who have pure emphysema: 1. Dyspnea
2. Too breathless, they cant eat,,thin,,weight loss, so we think that they have malignant tumor.
-in patients who have pure emphysema without bronchitis ,,barrel chest bcoz of the increase size of the lung, prolong expiration try to exhale more to get rid of air interrupted in his lung, they are called hunched over patients, hyperventilation so there is no hypoxia in the early stages ,,the gas exchange will stay adequate and blood gas values will stay normal, pink puffers,,,pink bcoz the gases are normal and no cyanosis, puffers bcoz they are trying to exhale to get rid of gases in their lungs.
-conditions related to emphysema but are not true emphysema:
1—compensatory emphysema, the accurate name is compensatory over inflation of the lung,,,if we remove one lung, the compensation will be in the other lung,,enlargment of air spaces without destruction of the alveolar septa,,this also can be seen in the same lung if we remove part of it.
2—obstructive over inflation,,, the patient have partial or subtotal or incomplete obstruction of the airway, the gas will enter during inspiration and will not exit during expiration, accumulation of air inside air space, dilatation and distention due without destruction of the alveolar septa,,the obstruction may be due to tumor or foreign object, this is an emergency and we should remove it,,
-if we have complete obstruction, we have atelectasis,,the air will be resorbed.
3—bollus emphysema, air spaces will be 1 cm in diameter, include any type of emphysema, not specific.
4—mediastinal (interstitial) emphysema:- entrance of air into the connective tissue stroma of the lung,mediastinam or subcutaneous tissue of head and neck, it occurs spontaneously with sudden increase in the intra alveolar pressure, violent cough or violent vomiting and it occurs in children and in perforating injury and fracture, we hear crepitating sound if we touch the subcutaneous tissue, the patient will blow up like a balloon.
Chronic bronchitis
Causes:-cigarette smokers and urban cities and air pollution.
Clinical definition:persistant productive cough for 3 consecutive months in at least 2 consecutive years.
Three forms : 1\ simple chronic bronchitis, productive cough without evidence of air flow obstruction.
2\ chronic asthmatic bronchitis, chronic bronchitis with hyper responsive air ways and intermittent period of bronchospasm like asthmatic patients.
3\chronic obstructive bronchitis, with time and in severe cases in heavily smokers there is air flow obstruction and obstruction of the small air way and associated with emphysema.
-pathogenesis: in simple—hyper secretion of mucus and productive cough bcoz of hypertrophy of mucus gland in trachea and main brain stem bronchi which are lined by pseudostraified ciliated epithelium with goblet cells and under the sub epithelium there is sub mucosa mucus secreting gland….the small airway (2-3 mm) are lined by pseudostratified columnar epithelium without goblet cells,,,metaplasia,,goblet cells in small airway, hyper secreting of mucus..
-nicotine is chemoattractive factor for many inflammatory cells: cd8+,neutrophil,macrophage.
-in contrast to asthma,,easinophils are lacking in chronic bronchitis unless the patient have chronic asthmatic bronchitis.
In obstruction:-the obstruction not in the main stem or trachea, it will be in distal or small air way….causes: 1—smal airway disease, mild degree of obstruction, fibrosis of the bronchus wall and peribronchus fibrosis.
2—chronic bronchitis + emphysema (co-existence emphysema),,obstrubtive,,loss of elastic tissue, severe COPD,,susceptible to infection.
Morphology: grossly—swelling and hyperemic lining epithelium,,inflammation,,mucus production, covered with mucus purulent bcoz of pus and superimposed infection,,(2-3) airway plugged with mucus secretion.
Histological: enlarged of mucus gland in trachea and large bronchioles, inflammatory cells…
Symptoms: (in simple)…production of sputum
(in obstructive)..no hyperventilation,,disterbance in blood gases, hypoxemia and hypercapnia and in severe cases cyanosis, blue blutters,,obese for unknown reason
-hypoxemia,,spasmed pulmonary artery, repeated spasms, pulmonary hyper tension, right sided heart failure, core pulmona?,,recurrent infection, respiratory failure, death
Pathology sheet #21
Done by : yasmine nofal

This sheet is dedicated to my best friends,,Dana ,,Nida2 ,,M2omen
I REALLY MISS U GUYS
And to my lovely brothers,,Yzn al- Masri and A7mad Jber