بسم الله الرحمن الرحيم

1. بسم الله الرحمن الرحيم

2. Community-Acquired Pneumonia B.Hajikarim ZUMS 2010

3. Importance of CAP • A major cause of death globally • Death rate due to pneumonia: 75000 • High incidence & mortality • patients per year: 4,000,000 • Mortality Rate: 2-30% • High rate of hospitalization • (600,000/15%)

4. CAP In The Past DECADE Dramatic changes in the etiology (Emerging pathogens) Growth of antimicrobial resistance Dramatic changes in the diagnosis & management

5. Pathogenesis • Defense mechanisms: • Filtering system • cough, sneezing, & reflex glottis • ciliated cells • Clearing system • Macrophages • T & B lymphocytes

6. Transmission routes: • Aspiration of oropharyngial colonization • Inhalation of infectious aerosols • Hematogenous dissemination • Direct inoculation

7. ETIOLOGY OF COMMUNITY-ACQUIRED PNEUMONIA • Pathogen not defined in as many as 50 % patients even with extensive diagnostic testing • S. pneumonia is the leading cause of CAP • H. influenzae ( type B), S. aureus, and gram (-) bacteria each account for 3 to 10 % • Staph aureus CAP is usually seen in the elderly and as post-influenza pneumonia

8. ETIOLOGY OF COMMUNITY-ACQUIRED PNEUMONIA • P. aeruginosa causes CAP in neutropenia, cystic fibrosis, HIV infection & bronchiectasis • N. meningitidis, M. catarrhalis & S. pyogenes can occasionally cause CAP • Anaerobic organisms are implicated in aspiration pneumonia and lung abscess • MRSA, M. tuberculosis & certain viral agents are common in nursing-home patients

9. Community acquired pneumonia (CAP) • Definition: • Acute signs & symptoms (respiratory or nonrespiratory) • New radiographic infiltrate • Acquisition of infection from outside the confines of a hospital

10. Clinical approach to pneumonia • History • Physical examination • Age • Epidemiologic data • Predisposing conditions

11. History • Typical or atypical pneumonia syndromes • Host consideration: • Neonates (no fever, mild & prolonged symptoms) • Young infants (viral pneumonia with respiratory distress & fever +/- sepsis) • Elderly (Changes in eating habit or mental function, minimum of respiratory symptoms)

12. History • Special considerations by organism: • M.TB & fungal pneumonia (gradual onset) • Mycoplasma & Chlamydia pneumonia (protracted cough, minimum sputum) • Legionnaires’ disease (relative bradycardia, renal, liver. Mental & GI abnormalities)

13. Physical examination • Signs of nonpneumonic infection • Signs of pleural effusion • Signs of anomalies lead to intrapulmonary process(DVT, clubbing, …) • Host considerations(very young & very old patients ,immune status)

14. Epidemiologic data • Family history(RSV, Mycoplasma.p, Influenza) • Travel history • Unusual contact(with animal, birds, excavation) • Seasonal & geographic differences • Patients living circumstances

15. Age • Newborn: Viruses (CMV,Rubella,HSV) Bacteria (GBS) • 1 - 3 m:Viruses (RSV, influenza & Para.inf) Bacteria (Chlamidia.tracho, Bordetella) • 3m -5Y:Viruses (RSV, Para.in, Adeno, Influ) Bacteria (S.Pneu, H.inf, Chla.P, Myco.P)

16. Age • 5 - 18Y: Viruses( Para.inf, Influ, Adeno) Bacteria (Myco, Chla, Pneu) • 18 -65Y: Viruses (Para.inf, Influ, Adeno) Bacteria(Myco.P, Chla.P, S.Pneu) • Over 65Y:Bacteria (S.Pneumo, H.inf, gr neg,Staph, mora.C,Legio.P Viruses

17. Predisposing conditions • In alcoholics: S.pneumonia, K.pneumonia, H.Influenza, M.Tuberculosis • Aspiration Of URT secretions • Chronic obstructive pulmonary disease: H.influenza, S.pneumonia, Moraxella catarralis • Cystic fibrosis: Staphylococcal & Pseudomonas infection • Post influenza bacterial pneumonias

18. Predisposing conditions • Immune status (including HIV/AIDS): • Hypogammaglubolinemia:Encapsulated bacteria • Sever neutropenia: Pseudomonas, Staphylococcal & Fungal inf. • HIV & AIDS :Consider CD4 count • Corticosteroid therapy:M.TB, Nocardial infections

19. Clinical approach to pneumonia(Review) • History • Physical examination • Age • Epidemiologic data • Predisposing conditions

20. Diagnostic evaluation • Baseline assessment • Outpatient assessment • Inpatient assessment

21. Baseline assessment • Chest X.ray useful for: • Diagnosis of pneumonia • Diagnosis of etiologic agents • Location of infiltration • Cavitations • Volume loss • Pleural effusion • Mediastinal adenopathy

22. Baseline assessment • Chest X.ray useful for: • Detecting associated conditions • Follow up (rapid changes over 8-36 h) • Patients clinically improving(gradually or even longer clearing) • Patients not improving(bronchial obstruction, super infection, associated effusion, abscess)

23. Pneumococcal pneumonia: lobar consolidation affecting both lungs. An air bronchogram is easily seen in the left middle zone

24. Mycoplasma pneumonia: patchy consolidation in several areas in both lungs

25. Staphylococcal pneumonia: pneumatoceles (arrowed) in right middle and lower lobes and in left lower lobe (infant) Posteroanterior lateral

26. Pulmonary tuberculosis: consolidation & cavitation of left upper lobe

27. Pulmonary tuberculosis: extensive consolidation of the left lung with partial collapse. Less severe changes are seen on the right

28. Tuberculosis of mediastinal glands: widening of superior mediastinum by enlarged right paratrachael lymph nodes

29. Tuberculous pleurisy: small right pleural effusion

30. Lung abscess: abscess cavity in lower lobe of right lung. posteroanterior lateral

31. Chest x-ray • False negative results • High resolution CT (HRCT) is more sensitive for the evaluation of: • interstitial disease • bilateral disease • cavitations • empyema • hilar adenopathy

32. Outpatient assessment • Sputum stains: • gram staining of sputum • Appearance • Adequacy • Unsuspected gram negative organisms • Acid fast smear & culture

33. Gram's stain of expectorated sputum • Sensitivity and specificity vary widely depending on the criteria used to define a "positive” stain • > 25 neutrophils and < 10 squamous epithelial cells per low power field • Cytologic screening criteria not evaluated for Legionella, mycobacteria or viral infections • Direct staining of sputum may be diagnostic for Mycobacterium sp., endemic fungi, Legionella sp. (DFA stain) & P. carinii

35. Sputum Gram stain

36. Sputum Gram Stain

37. Inpatient assessment Recovery of the organism • Obtaining of different diagnostic specimens before treatment: • Blood culture • A good sputum for smear & culture • Aspiration & culture of pleural fluid • Other body secretion cultures

38. Invasive diagnostic techniques • Transtracheal aspiration • Bronchoscopy with a protected brush catheter • Bronchoalveolar lavage with or without balloon protection • Direct needle aspiration of the lung

39. Diagnostic evaluation(Review) • Baseline assessment • Outpatient assessment • Inpatient assessment

40. Management • Choose the Environment of management By: Pneumonia Severity Index.

41. PNEUMONIA SEVERITY INDEX (PSI) CLINICAL PREDICTION RULE • The PSI rule stratified adults with radiographic evidence of CAP into five classes for risk of death from all causes within 30 days of presentation • Predictor Variables • age • sex • comorbid illnesses • physical findings • selected laboratory findings • The PSI is applied in two steps

42. PNEUMONIA SEVERITY INDEX

43. Step 2 of prediction rule • Age (age years) • Coexisting illnesses (10 – 80) • Physical examination findings (10-65) • Laboratory and radiographic findings (10 – 110)

44. STRATIFICATION OF RISK SCORE

45. SEVERE COMMUNITY-ACQUIRED PNEUMONIA There is no universally accepted definition of severe CAP: ATS definition: • Requirement for mechanical ventilation • Requirement for vasopressors for more than 4 h • SBP < 90 mmHg • Severe respiratory failure defined by a Pao2/Flo2 ratio <250 • Multilobar involvement

46. Management Antibiotic choices

47. outpatient < 60 yrs • Amoxicillin (500mg TDS) • Macrolides Erythromycin (500mg Qid) Azithromycin (500mg then 250mg daily) Clarithromycin (500mg BD) • Doxycycline (100mg BID) • Flouroquinolone (IDSA)

48. outpatient 60 yrs or > or adult with preexisisting disease 1. beta-lactam ( cefpodoxime, high dose amoxicillin, amox-clav., ceftrioxone) PLUS macrolide or doxycycline 2. antipneumococcal quinolone (only IDSA)

49. Pathogen Resistance in CAP • Three specific pathogen: H.inf, S.pneu, M.cata • Linear increase in the magnitude of ampicillin resistance with: H.inf=33%, M.cata=100% • High prevalence of penicillin resistance with S.pneu=35% • Non-betalactam resistance with S.pneu: Macrolides=26% clindamycin=9% Tetracycline=16% Chloramphenicole=8% TMP-SMZ=30% Fluoroquinolones=0.2%

50. DURATION OF TREATMENT a) coexisting illness and/or bacteremia b) the severity of illness at the onset of antibiotic therapy c) the subsequent hospital courseorganism duration of treatment S. pneumoniae approximately 7 to 10 days M. pneumoniae 10 to 14 days C. pneumoniae 10 to 14 days Legionnella pneumonia 14 days 21 days if immunocompromised