PATHOLOGY OF PENUMONIA.pptx

Pneumonia is the inflammation of the lung parenchyma. This lecture deals with pathology of pneumonia in short and concise manner for nursing students. It includes the types of pneumonia, lobar pneumonia, bronchial pneumonia, interstitial pneumonia , hospital acquired pneumonia, community acquired pneumonia and so on. It also discusses the stages of pneumonia that is initial response, red hepatization, grey hepatization and resolution

1. PNEUMONIA PATHOLOGY By : Ms. Saili Gaude Principal Shivam College of Nursing , Amirgadh

2. INTRODCUTION The term pneumonia and pneumonitis is commonly used for inflammation of lung Pneumonia is a common disorders which can be acute or chronic It is an infective disorder of the lungs

3. DEFINITION Acute inflammation of the lung parenchyma distal to the terminal bronchioles.

4. ETIOPATHOGENESIS 1. Inhalation of the microbes present in air 2. Aspiration of organisms from the nasopharynx 3. Hematogenous spread from distant focus of infection 4. Direct spread from nearby infected areas

5. PREDISPOSING FACTORS 1) Altered consciousness: due to unconsciousness patient can aspirate the food content into the windpipe. Coma, brain injury, seizures, cerebrovascular accidents, drug overdose, alcoholism etc. 2) Depressed cough and glottic reflexes : when due to some reason the patient cannot cough effectively , the person may aspirate due to ineffective cough reflex and glottic reflex which are normally required to close the windpipe. Old age, thoracic or abdominal surgeries, neuromuscular disease, endotracheal tube insertion, tracheostomy etc.

6. 3) Impaired mucociliary transport : normally the airways are protected by the mucus and cilia which together traps and helps to throw any microorganism or foreign body out of the airways preventing its entry into the lungs. When the mucociliary epithelium is damaged and cannot function, pneumonia occurs. Smoking, viral respiratory infections, immotile cilia syndrome, inhalation of hot or corrosive substance can cause damage to the cilia and mucosa.

7. 4) Impaired alveolar macrophage function : macrophages are WBCs which are also present in alveoli. When they fail to protect the alveoli , pneumonia occurs. Smoking, hypoxia, starvation, anemia , edema and viral respiratory infections. 5) Endobronchial obstruction : when the bronchi is obstructed due to any reasons such as tumor , cystic fibrosis, bronchitis etc, the bronchi cannot be effectively cleared out. The mucus of the bronchi which contains trapped infective organism can reach the lungs if they are not thrown out and cleared.

8. 6) Immunocompromised state: disorders of immune system where the immune system fails to work properly can also allow entry of micro-organism any where in the body including lungs.

9. CLASSIFICATION ANATOMICAL CLASSIFICATION

10. CLASSIFICATION Based on CLINICAL SETTING

11. HOSPITAL ACQUIRED PNEUMONIA Pneumonia that occurs 48 hours or more after admission into the hospital. Occurs due to iatrogenic causes

12. COMMUNITY ACQUIRED PNEUMONIA Pneumonia that occurs in the community and presents within 48 hours of admission. Occurs due to causative organisms in the community

13. VENTILATOR ASSOCIATED PNEUMONIA Pneumonia that develops after 48 hours after intubation. Occurs as a result of complication of intubation, or mechanical ventilation

14. CLASSIFICATION Based on CAUSATIVE FACTORS

15. BACTERIAL PNEUMONIA Common causative organisms: 1. Pneumococcal pneumonia 2. Staphylococcal Pneumonia 3. Streptococcal pneumonia 4. Pneumonia by gram negative aerobic bacteria

16. VIRAL PNEUMONIA Common viral infections 1. Respiratory syncytial virus 2. Influenza 3. Rhinovirus 4. Adenovirus 5. Cytomegalovirus

17. FUNGAL PNEUMONIA Common fungal pneumonia includes Pneumocystis- Pneumocystis carinii & jirovecii Aspergillosis – aspergillus fumigatus Mucormycosis - mucor & Rhizopus Candidiasis – candida albicans Histoplasmosis – histoplasma capsulatum Blastomycosis – Blastomyces dermatitidis

18. CLASSIFICATION Aspiration Pneumonia Hypostatic Pneumonia Lipid Pneumonia

19. Lobar Pneumonia Acute infection of a part of a lobe or an entire lobe of lung Sometime even more than 2 lobes maybe involved

20. BRONCHIAL PNEUMONIA Also called lobular pneumonia Infection of the bronchioles extending into the surrounding alveoli Patchy consolidation of lungs Causative organism – bacteria & virus . Acute bronchiolitis occurs

21. LEGIONELLA PNEUMONIA Also called legionnaire’s disease Causative organism – legionella pneumophilia Epidemic disorder spread through contaminated water May cause widespread infection in the lungs Consolidation of the entire lobe Pleural effusion maybe present

22. VIRAL & MYCOPLASMA PNEUMONIA Patchy inflammatory changes Present in interstitial tissues of lungs No exudate thus called atypical pneumonia Interstitial inflammation Usually affects only the upper respiratory tract

23. Fungal pneumonia Usually occurs in immunosuppressed individuals Rarely serious in healthy individuals Opportunistic infection with pneumocystis Transmitted by inhalation route mainly Very common in HIV patients

24. NON INFECTIVE PNEUMONIA - ASPIRATION Occurs due to inhalation of different agents into the lungs Gastric content aspiration, aspiration of food, foreign body aspiration, aspiration of infective organisms from oral cavity etc. Hemorrhagic pulmonary edema and chemical pneumonitis may occur Secondary bacterial infection may occur Patient may also develop asphyxiation or laryngospasm due to aspiration which leads to death Mostly right lung is affected. Non sterile aspirate- causes widespread bronchopneumonia with multiple areas of necrosis and suppuration

25. HYPOSTATIC PNEUMONIA Collection of edema fluid and secretions in lungs due to prolonged immobility The long term accumulation of fluid in the lung can get infected by secondary infection. Usually affects bedridden , unconscious or paralyzed patients Bacteria commonly causes infection

26. LIPID PNEUMONIA Exogenous lipid pneumonia – caused by aspiration of variety of oily materials Endogenous lipid pneumonia – tissue breakdown following airway obstruction causes lipid to be released which causes this pneumonia Cut surface- golden yellow Formation of granulomas

27. MORPHOLOGY 4 STAGES STAGE 1- INITIAL PHASE STAGE 2- EARLY CONSOLIDATION STAGE 3- LATE CONSOLIDATION STAGE 4- RESOLUTION

28. STAGE 1- CONGESTION Also called initial phase Acute inflammatory response 1-2 days GROSS MORPHOLOGY – Enlarged lobe Heavy Dark red Congested lobe Cut section causes blood stained frothy fluid

29. STAGE 1- CONGESTION HISTOLOGICALLY – Dilation & congestion of capillaries Edema in air spaces RBCs and neutrophils in intralveolar spaces Presence of bacteria

30. STAGE 2- RED HEPATISATION Also called early consolidation 2-4 days Liver like consistency of affected lobe GROSS MORPHOLOGY Red firm consolidated lobe Cut surface- airless, red pink dry granular Liver like consistency Serofibrinous pleurisy

31. STAGE 2- RED HEPATISATION HISTOLOGICALLY – Edema replaced by fibrin strand Marked cellular exudate Neutrophils with ingested bacteria Less prominent alveolar septa

32. STAGE 3- GREY HEPATISATION Also called late consolidation 4-8 days GROSS MORPHOLOGY Firm & heavy Cut surface – dry granular & grey Liver like consistency Fibrinous pleurisy

33. STAGE 3- GREY HEPATISATION HISTOLOGICALLY – Dense fibrin strands Cellular exudate of neutrophils decreases RBCs decreases in lobe Pyknotic nuclei Macrophages appears in exudate Less organisms Degenerated micro-organisms

34. STAGE 4 - RESOLUTION Begins by 9 th day without treatment Completed by 1 to 3 week With treatment resolution occurs by 3 rd day GROSS MORPHOLOGY Solid components turns into liquid due to enzymatic action Normal aeration Softening starts from center to periphery Cut surface- grey red, dirty brown and frothy Yellow creamy fluid

35. STAGE 4- RESOLUTION HISTOLOGICALLY Macrophages in alveoli Decreased neutrophils Phagocytic macrophages Alveolar capillaries engorged Granular strands of fibrin Removal of fluid and cellular exudate from lungs Return of normal lung parenchyma

36. COMPLICATIONS 1. organization- fibrosed, tough airless leathery lung tissue called carnification 2. pleural effusion- may resolve naturally but can sometimes causes both the pleura to stick to each other 3. Empyema- pus in pleural cavity 4. lung abscess- rare complication , abscess forms in lung parenchyma 5. metastatic infection – infection may spread to pericardium and heart

37. CLINICAL FEATURES Sudden onset Shaking Chills Fever Malaise Expectoration with mucoid or purulent sputum Tachypnea cyanosis

38. DIAGNOSTIC TESTS Physical examination Blood cultures Chest radiograph Sputum cultures CT scan

39. TREATMENT Oral antibiotics Rest Lots of fluids Bacterial pneumonia – - Amoxicillin - Fluroquinolones - Cephalosporin - Aminoglycosides Viral pneumonia- - Rimatidine Amantadine

40. PREVENTION Vaccination – H.influenza and S. Pneumoniae in the 1 st year of life , repeated 5-10 years Antibiotics – prophylactically Treating underlying diseases Cessation of smoking