Chapter 22 Pulmonary Infections Copyright © 2013, 2009, 2003, 1999, 1995, 1990, 1982, 1977, 1973, 1969 by Mosby, an imprint of Elsevier Inc.

2 Learning Objectives State the incidence of pneumonia in the United States and its economic impact. Discuss the current classification scheme for pneumonia and be able to define hospital- acquired pneumonia, health care–acquired pneumonia, and ventilator-associated pneumonia. Recognize the pathophysiology and common causes of lower respiratory tract infections in specific clinical settings.

Copyright © 2013, 2009, 2003, 1999, 1995, 1990, 1982, 1977, 1973, 1969 by Mosby, an imprint of Elsevier Inc. 3 Learning Objectives (cont.) List the common microbiological organisms responsible for community acquired and nosocomial pneumonias. Describe the clinical findings seen in patients with pneumonia. State the radiographic findings seen in patients with pneumonia; state why some patients with pneumonia may have a normal chest radiograph. Describe the risk factors associated with increased morbidity and mortality in patients with pneumonia.

Copyright © 2013, 2009, 2003, 1999, 1995, 1990, 1982, 1977, 1973, 1969 by Mosby, an imprint of Elsevier Inc. 4 Learning Objectives (cont.) State the criteria used to identify an adequate sputum sample for Gram stain and culture. Describe the techniques used to identify the organism responsible for a nosocomial pneumonia. List the latest recommendations regarding the antibiotic regimens used to treat various types of pneumonia, both empiric and pathogen specific.

Copyright © 2013, 2009, 2003, 1999, 1995, 1990, 1982, 1977, 1973, 1969 by Mosby, an imprint of Elsevier Inc. 5 Learning Objectives (cont.) Discuss strategies that can be used to prevent pneumonia. Describe how the respiratory therapist aids in diagnosis and management of patients with suspected pneumonia.

Copyright © 2013, 2009, 2003, 1999, 1995, 1990, 1982, 1977, 1973, 1969 by Mosby, an imprint of Elsevier Inc. 6 Introduction Infection involving lungs is called “pneumonia” or “lower respiratory tract infection” Major cause of morbidity & mortality in U.S. & the world In U.S., about 4 million cases of pneumonia occur each year Eighth leading cause of death in U.S.

Copyright © 2013, 2009, 2003, 1999, 1995, 1990, 1982, 1977, 1973, 1969 by Mosby, an imprint of Elsevier Inc. 7 Classification Community-acquired pneumonia (CAP)  Acute  Chronic Health care–associated pneumonia (HCAP)  Pneumonia occurring in any patient hospitalized for 2 or more days in past 90 days or:  Any patient with pneumonia who, in past 30 days, has resided in a long-term care facility

Copyright © 2013, 2009, 2003, 1999, 1995, 1990, 1982, 1977, 1973, 1969 by Mosby, an imprint of Elsevier Inc. 8 Classification (cont.) Hospital-acquired pneumonia (HAP)  Acute lower respiratory tract infection that occurs in hospitalized patients more than 48 hours after admission  Second most common nosocomial infection Ventilator-associated pneumonia (VAP)  Pneumonia that develops more than 48 to 72 hours after intubation

Copyright © 2013, 2009, 2003, 1999, 1995, 1990, 1982, 1977, 1973, 1969 by Mosby, an imprint of Elsevier Inc. 9 Ms. Jones, a 70 year-old female patient has been admitted to the hospital with a diagnosis of acute right lower lobe pneumonia. Her last hospital admission was 120 days before. Her pneumonia should be classified as: A.HAP B.HCAP C.CAP D.VAP

Copyright © 2013, 2009, 2003, 1999, 1995, 1990, 1982, 1977, 1973, 1969 by Mosby, an imprint of Elsevier Inc. 10 Pathogenesis Inhalation of aerosolized infectious particles Aspiration of organisms Direct inoculation of organisms into lower airways Spread of infection to lung from adjacent structures

Copyright © 2013, 2009, 2003, 1999, 1995, 1990, 1982, 1977, 1973, 1969 by Mosby, an imprint of Elsevier Inc. 11 Pathogenesis (cont.) Spread of infection to lung from blood Reactivation of latent infection, usually resulting from immunosuppression - e.g., Pneumocystis carinii, reactivation tuberculosis, cytomegalovirus

Copyright © 2013, 2009, 2003, 1999, 1995, 1990, 1982, 1977, 1973, 1969 by Mosby, an imprint of Elsevier Inc. 12 Ms. Jones was diagnosed with a CAP. Which of the following microorganisms is most likely to have caused Ms. Jones’ pneumonia? A. M. tuberculosis B. C. difficile C. S. aureus D. S. pneumoniae

Copyright © 2013, 2009, 2003, 1999, 1995, 1990, 1982, 1977, 1973, 1969 by Mosby, an imprint of Elsevier Inc. 13 Clinical Manifestations Patients with CAP typically have fever, cough, sputum production, pleuritic chest pain, & dyspnea In elderly, pneumonia may not cause fever or cough; it may simply present as dyspnea, confusion, worsening of CHF, or failure to thrive

Copyright © 2013, 2009, 2003, 1999, 1995, 1990, 1982, 1977, 1973, 1969 by Mosby, an imprint of Elsevier Inc. 14 Clinical Manifestations (cont.) VAP traditionally presents with new onset of fever, purulent endotracheal secretions, & new infiltrate Diagnosis of HAP can be difficult in patient with preexisting pulmonary abnormalities on chest radiograph

Copyright © 2013, 2009, 2003, 1999, 1995, 1990, 1982, 1977, 1973, 1969 by Mosby, an imprint of Elsevier Inc. 15 Ms. Jones, our previous patient, was admitted due to a community acquired pneumonia. She presented with gradual onset of fever, headache, diarrhea, and cough, often with minimal sputum production. Coughing was often a relatively minor symptom at the outset. This pneumonia can be classified as: A.Atypical pneumonia B.Anaerobic pneumonia C.Typical pneumonia D.Bacterial pneumonia

Copyright © 2013, 2009, 2003, 1999, 1995, 1990, 1982, 1977, 1973, 1969 by Mosby, an imprint of Elsevier Inc. 16 Chest Radiograph Diagnosis of pneumonia is established by presence of new infiltrate on chest film. However:  Not all outpatients require chest radiograph  Normal chest x-ray does not exclude diagnosis of pneumonia Early pneumonia Dehydration P. jiroveci infection

Copyright © 2013, 2009, 2003, 1999, 1995, 1990, 1982, 1977, 1973, 1969 by Mosby, an imprint of Elsevier Inc. 17 Chest Radiograph (cont.) Consolidation of entire lobe is called “lobar pneumonia” “Bronchopneumonia” refers to presence of patchy infiltrate surrounding one or more bronchi Both patterns suggest bacterial pathogen Pleural effusions are common in bacterial pneumonia

Copyright © 2013, 2009, 2003, 1999, 1995, 1990, 1982, 1977, 1973, 1969 by Mosby, an imprint of Elsevier Inc. 18 Chest Radiograph (cont.) Interstitial infiltrates (if diffuse) suggest viral disease, P. jiroveci, or miliary tuberculosis Cavitary infiltrates (pneumatoceles) are seen in reactivation tuberculosis & some fungal infections Chest radiograph is less helpful in diagnosis of VAP because patient often has other causes of pulmonary infiltrates

Copyright © 2013, 2009, 2003, 1999, 1995, 1990, 1982, 1977, 1973, 1969 by Mosby, an imprint of Elsevier Inc. 19 Clinical Diagnosis of VAP Fever Purulent sputum Leukocytosis New pulmonary infiltrates

Copyright © 2013, 2009, 2003, 1999, 1995, 1990, 1982, 1977, 1973, 1969 by Mosby, an imprint of Elsevier Inc. 20 Risk Factors for Mortality/Assessing Need for Hospitalization Many cases of CAP can be treated on outpatient basis Challenge is to identify those patients at higher risk who need hospitalization

Copyright © 2013, 2009, 2003, 1999, 1995, 1990, 1982, 1977, 1973, 1969 by Mosby, an imprint of Elsevier Inc. 21 Risk Factors for Mortality/Assessing Need for Hospitalization (cont.) Risk of death in pneumonia is increased in:  Male patients  Hypotension  Tachypnea  Diabetes  Cancer  Neurologic disease  Bacteremia  Leukopenia  Multiple lobe involvement

Copyright © 2013, 2009, 2003, 1999, 1995, 1990, 1982, 1977, 1973, 1969 by Mosby, an imprint of Elsevier Inc. 22 All of the following are considered risk factors for the development of HAP and VAP, except: A.Use of an endotracheal tube B.Foley catheter insertion C.Prior antibiotic therapy D.Contaminated ventilator equipment

Diagnostic Studies Copyright © 2013, 2009, 2003, 1999, 1995, 1990, 1982, 1977, 1973, 1969 by Mosby, an imprint of Elsevier Inc. 23

Diagnostic Studies (cont.) CAP  Respiratory therapists play key role in collecting sputum samples for microbiological examination  Satisfactory specimen contains >25 leukocytes and <10 squamous epithelial cells per hpf  Presence of acid-fast bacilli in stain sputum samples suggests tuberculosis  Blood cultures should be obtained in severe cases of pneumonia Copyright © 2013, 2009, 2003, 1999, 1995, 1990, 1982, 1977, 1973, 1969 by Mosby, an imprint of Elsevier Inc. 24

Diagnostic Studies (cont.) Nosocomial Pneumonias: HAP, HCAP, VAP  Accurate diagnosis is very difficult Copyright © 2013, 2009, 2003, 1999, 1995, 1990, 1982, 1977, 1973, 1969 by Mosby, an imprint of Elsevier Inc. 25

Copyright © 2013, 2009, 2003, 1999, 1995, 1990, 1982, 1977, 1973, 1969 by Mosby, an imprint of Elsevier Inc. 26 A positive acid-fast bacilli in stained specimens of sputum is an indication of the presence of which of the following microorganisms? A. P. jiroveci B. S. pneumoniae C. Legionella D. M. tuberculosis

Copyright © 2013, 2009, 2003, 1999, 1995, 1990, 1982, 1977, 1973, 1969 by Mosby, an imprint of Elsevier Inc. 27 Therapy Choice of antibiotic for patient with CAP depends on:  Age of patient  Severity of illness  Risk factors for specific organisms  Results of initial diagnostic tests For hospitalized patients who are not critically ill:  Empirical regimen of advanced macrolide plus second- or third-generation cephalosporin or beta- lactam/beta-lactamase inhibitor is recommended

Copyright © 2013, 2009, 2003, 1999, 1995, 1990, 1982, 1977, 1973, 1969 by Mosby, an imprint of Elsevier Inc. 28 Therapy (cont.) Therapy should be started within 4 hours of hospital admission Duration of therapy for CAP is generally for minimum of 5 days Legionnaires’ disease requires minimum of 2 weeks Elderly & those with comorbidities may also require longer therapy

Copyright © 2013, 2009, 2003, 1999, 1995, 1990, 1982, 1977, 1973, 1969 by Mosby, an imprint of Elsevier Inc. 29 Prevention Prevention of CAP centers around immunization Immunization is indicated for individuals:  Over age 60 years  With chronic lung or heart disease

Prevention (cont.) Copyright © 2013, 2009, 2003, 1999, 1995, 1990, 1982, 1977, 1973, 1969 by Mosby, an imprint of Elsevier Inc. 30

Copyright © 2013, 2009, 2003, 1999, 1995, 1990, 1982, 1977, 1973, 1969 by Mosby, an imprint of Elsevier Inc. 31 Tuberculosis (TB) Incidence of TB steadily declined after introduction of effective antibiotics (1950s) From 1985 to 1992, incidence increased due to emergence of AIDS Since 1992, incidence of TB has declined again but remains problem for selected groups of patients (e.g., immunocompromised, those living in crowded conditions, those with poor access to health care, etc.)

Copyright © 2013, 2009, 2003, 1999, 1995, 1990, 1982, 1977, 1973, 1969 by Mosby, an imprint of Elsevier Inc. 32 Tuberculosis (cont.) TB is acquired by inhalation of airborne droplets containing M. tuberculosis Most people exposed to TB do not develop active infection as TB is controlled by an intact immune system People who are positive for TB but asymptomatic are said to have “latent TB”  If they subsequently become debilitated, it may develop into reactivation TB

Copyright © 2013, 2009, 2003, 1999, 1995, 1990, 1982, 1977, 1973, 1969 by Mosby, an imprint of Elsevier Inc. 33 Tuberculosis (cont.) People who acquire infection upon initial exposure have “primary TB” Primary TB is most likely to occur in HIV patients Primary TB causes fevers in 70% of patients, persisting for 14 to 21 days, in most cases Cough is less common

Copyright © 2013, 2009, 2003, 1999, 1995, 1990, 1982, 1977, 1973, 1969 by Mosby, an imprint of Elsevier Inc. 34 Tuberculosis (cont.) Chest x-ray usually shows lymphadenopathy, while an infiltrate is seen in 25% of cases In those without HIV infection, reactivation disease accounts for 90% of cases Most common symptoms in reactivation TB include fever, cough, night sweats, & weight loss Chest radiograph shows upper lobe infiltrates in 80% to 90% of reactivation TB cases

Copyright © 2013, 2009, 2003, 1999, 1995, 1990, 1982, 1977, 1973, 1969 by Mosby, an imprint of Elsevier Inc. 35 Tuberculosis (cont.) Extrapulmonary TB is defined as spread of organism beyond lung & may involve any organ  Most often occurs in CNS, musculoskeletal system, GI tract, & lymph nodes History is vitally important in diagnosis of patients with TB  Clinician should ask about symptoms, exposure, travel, prior history of TB, risk factors, etc…

Copyright © 2013, 2009, 2003, 1999, 1995, 1990, 1982, 1977, 1973, 1969 by Mosby, an imprint of Elsevier Inc. 36 Tuberculosis (cont.) Patients diagnosed or suspected of having TB should be placed in respiratory isolation Gold standard for diagnosis of TB is culture isolation of organism  Culture may take 4 to 6 weeks Acid-fast staining of expectorated sputum may be used in diagnosis Positive PPD skin test supports diagnosis in appropriate clinical setting

Copyright © 2013, 2009, 2003, 1999, 1995, 1990, 1982, 1977, 1973, 1969 by Mosby, an imprint of Elsevier Inc. 37 Tuberculosis (cont.) Negative skin test may occur in patients with HIV who are infected with TB Goals of treatment are to cure patient & prevent further transmission Daily observation therapy should be used Isoniazid, rifampin, pyrazinamide, & ethambutol are first-line antibuberculous medications Routine treatment should be given for 6 to 9 months

Copyright © 2013, 2009, 2003, 1999, 1995, 1990, 1982, 1977, 1973, 1969 by Mosby, an imprint of Elsevier Inc. 38 Role of Respiratory Therapist in Pulmonary Infections Collection of sputum samples as indicated Assist with bronchoscopy Administer chest physical therapy in selected cases Counsel patients in sputum clearance techniques such as PEP & autogenic drainage Model optimal infection control practices