2 Introduction Pneumonia is the 6th leading cause of death in the U.S. 90% of the deaths occur in persons over 65 years of age.The etiology is 50% idiopathicOnly 20% with specific organism in clinical practice
3 IntroductionAccording to the National Institutes of Health: “at any given time, the noses and throats of up to 70% of healthy people contain pneumococcus” (the most common cause of bacterial pneumonia).The paradigm for any type of pneumonia is the balance between the patient's host defenses, the virulence of the potential pathogen, and the size of the exposure to the pathogen.
4 DefinitionPneumonia defined as inflammation of the lung parenchyma; pneumonia is characterized by consolidation of the affected part and a filling of the alveolar air spaces with exudate, inflammatory cells, and fibrin.
5 Classification and categorization of bacterial pneumonia Anatomic/radiographic patterns of pneumoniaLobar pneumoniaBronchopneumoniaInterstitial pneumoniaSetting of infectionCommunity-acquired pneumonia CAPHealth care–associated pneumonia HCAPNursing home–associated pneumonia NHAPHospital-acquired pneumonia HAPVentilator-associated pneumonia VAPAspiration pneumonia
6 Pneumonia typesThe 2005 ATS/IDSA guidelines distinguish the following types of pneumonia :Community-acquired pneumonia (CAP) is defined as an acute infection of the pulmonary parenchyma in a patient who has acquired the infection in the community.Hospital-acquired (or nosocomial) pneumonia (HAP) is pneumonia that occurs 48 hours or more after admission and did not appear to be incubating at the time of admission.Ventilator-associated pneumonia (VAP) is a type of HAP that develops more than 48 to 72 hours after endotracheal intubation.
7 Pneumonia typesHealthcare-associated pneumonia (HCAP) is defined as pneumonia that occurs in a non-hospitalized patient with extensive healthcare contact, as defined by one or more of the following: - Intravenous therapy, wound care, or intravenous chemotherapy within the prior 30 days - Residence in a nursing home or other long-term care facility - Hospitalization in an acute care hospital for two or more days within the prior 90 days - Attendance at a hospital or hemodialysis clinic within the prior days
9 Frequency Inpatient, non-ICU Inpatient, ICU Outpatient S pneumoniae The most common etiologies of community-acquired pneumonia (CAP), listed in descending order of frequency are as follows :OutpatientS pneumoniaeM pneumoniaeH influenzaeC pneumoniaeRespiratory virusesInpatient, non-ICULegionella speciesAspirationInpatient, ICUS aureusGram-negative bacilli
10 HistopathologyLobar pneumonia: Four stages of inflammatory response are classically described, as follows:CongestionRed hepatizationGray hepatizationResolution
11 Mortality/MorbidityThe average length of hospital stay for a patient diagnosed with pneumonia was 5 daysPneumonia and influenza together were the sixth-eighth leading cause of death in the United States
12 History / SymptomsChest pain, dyspnea, hemoptysis (when clearly delineated from hematemesis), decreased exercise tolerance, and abdominal pain from pleuritis are also highly indicative of a pulmonary processRust-colored sputum - Frequently associated with infection by S pneumoniaeCurrant-jelly sputum - Frequently associated with infection by Klebsiella speciesFoul-smelling or bad-tasting sputum - Often produced by anaerobic infections
13 History / SymptomsNonspecific symptoms such as rigors or shaking chills, and malaise are common.Other nonspecific symptoms that may be seen with pneumonia include myalgias, headache, nausea, vomiting, diarrhea, and altered sensorium
14 Potential exposures - Travel, pets, occupation, environment History of various exposures can be helpful in determining possible etiologies and the likelihood of bacterial pneumonia, as follows:Exposure to contaminated air-conditioning or water systems -Legionella speciesExposure to overcrowded institutions (eg, jails, homeless shelters) -S pneumoniae, Mycobacteria, Mycoplasma, ChlamydophilaExposure to various types of animalsCats, cattle, sheep, goats -C burnetii, B anthracis (cattle hide)Turkeys, chickens, ducks, or other birds -C psittaciRabbits, rodents -F tularensis, Y pestis
16 Aspiration risks Patients at increased risk of aspiration with: AlcoholismAltered mental statusAnatomic abnormalities, congenital or acquiredDysphagiaGERDSeizure disorder
17 Physical examinationApproximately 80 % are febrile - frequently absent in older patientsA respiratory rate above 24 breaths/minute is noted in 45 to 70 % of patientsMost sensitive sign in elderly patientsTachycardia is common
19 Pneumonia ApproachThe following 3 aspects of disease are important in the management of pneumonia, in which diagnostic testing can play a pivotal role:Determining the presence of pneumoniaAssessing disease severity at the time of presentationIdentifying the causative agentDifferentiation between community-acquired pneumonia (CAP), health care–associated pneumonia (HCAP), hospital-acquired pneumonia (HAP), and other pulmonary pathology
20 DiagnosisOutpatients Testing for a microbial diagnosis is usually not performed in outpatients.This is appropriate since empiric treatment is almost always successful.In one study of over 700 ambulatory patients treated for CAP, empiric antibiotics (a macrolide or fluoroquinolone in >95 percent) were almost universally effective; only 1 percent required hospitalization due to failure of the outpatient regimenThe 2007 IDSA/ATS consensus guidelines suggest that routine tests to identify an etiology for CAP are optional for patients who do not require hospitalizationAn exception is in clinical or epidemiologic settings suggesting a critical microbe is the etiologic agent, in which tests for a microbial diagnosis are important
21 DiagnosisCritical microbes — Some microbes are critical to detect because they represent important epidemiologic challenges and/or serious conditions that require treatment different from standard empiric regimens. These organisms include:Legionella speciesInfluenza A and BAvian influenzaCommunity-associated methicillin-resistant Staphylococcus aureus MRSA
22 DiagnosisThe incidence of S. aureus in the HCAP and HAP groups were comparable (47 %) and significantly higher than in the CAP group (26 %).The rate of MRSA infection was also higher in HCAP and HAP patients compared to CAP (27 and 23 versus 9 % for CAP).
23 MDR pathogensHost risk factors for infection with MDR pathogens include :Receipt of antibiotics within the preceding 90 daysCurrent hospitalization of ≥5 daysHigh frequency of antibiotic resistance in the community or in the specific hospital unitImmunosuppressive disease and/or therapyPresence of risk factors for HCAP
24 Laboratory studiesDiagnostic testing in patients with suspected pneumonia is driven mostly by the possibility that the results would significantly alter empiric therapy and management decisions and whether the test is likely to have a high yield.The following initial tests are indicated with suspected pneumonia:Blood culture, prior to antibiotic therapySputum Gram stain and culture, prior to antibiotic therapy (if a good-quality, contaminant-sparse specimen containing <10 squamous epithelial cells per low-power field can be obtained)Sputum, serum, and/or urinary antigen test for Streptococcus pneumoniaeSputum and/or urinary antigen test for Legionella pneumophilaEndotracheal aspirate for culture in intubated patientsCulture and study of pleural fluid if effusion presentImmune serologies for Mycoplasma pneumoniae, Chlamydophila pneumoniae, L pneumophila, and Coxiella burnetii - Results usually not available until several weeks after infection
25 Severity of PneumoniaVarious systems to assess the severity of disease and risk of death exist and are in wide use, including :PSI/PORT (ie, Pneumonia Severity Index/Patient Outcomes Research Team score)CURB-65 system (ie, confusion, urea of 7 mmol/L, respiratory rate of 30 breaths/min, and low systolic [90 mm Hg] or diastolic [60 mm Hg] blood pressure)
26 Imaging Studies Lobar pneumonias Bronchopneumonias S pneumoniae: homogenous parenchymal lobar opacities with air bronchograms; round opacity stimulating a pulmonary mass, called round pneumonia.K pneumoniae: lobar expansion with bulging of interlobular fissures as well as cavitations.L pneumophila: Radiologic resolution tends to lag far behind clinical improvement (8 wk to clear).BronchopneumoniasS aureus: Lobar enlargement with bulging of interlobular fissures can be seen in severe cases; abscesses, cavitations (with air-fluid levels), and pneumatoceles are commonly seen; 30-50% of patients develop pleural effusions, half of which are empyemas.P aeruginosa: usually all lobes are involved, with a predilection for the lower lobes; necrosis and cavitation occur frequently; pulmonary vasculitis can produce areas of pulmonary infarction that radiographically resembles invasive aspergillosisH influenzae: Pleural effusion is present in approximately half of infected individuals.
27 Imaging Studies Aspiration pneumonias: Gravity-dependent portions of the lungs (affected by patient positioning)The right lung is affected twice as often as the left lung
34 ProceduresBronchoscopy with or without bronchoalveolar lavage (BAL): Lung tissue can be visually evaluated and bronchial washing specimens Nonbronchoscopic bronchoalveolar lavage, mini-BAL: BAL can be performed without the use of a bronchoscope.Transtracheal aspiration for cultureThoracentesis:Essential procedure in patients with a parapneumonic pleural effusion.
35 MORTALITY The mortality rate ranged from: 5.1 % for combined ambulatory and hospitalized patients13 % in hospitalized patients36 % in patients admitted to the ICU.
36 PREDICTORS OF MORTALITY Risk factors at presentation British Thoracic Society BTS found a 21-fold increase in mortality in patients who had two or more of the following findings :Blood urea nitrogen greater than 20 mg/dL (7 mmol/L)Diastolic blood pressure less than 60 mmHgRespiratory rate above 30 per minuteThe presence of all three variables predicted a nine-fold greater risk for death with 70 % sensitivity and 84 % specificity
37 PREDICTORS OF MORTALITY CURB-65 scoreThese findings plus confusion (based upon a specific mental test or new disorientation to person, place, or time) and age greater than 65 yearsPrediction rule for prognosis to determine whether a patient should be admitted to the hospital
41 Pneumonia Severity Index Classes I and II - Outpatient managementClass III - Admission to an observation unit or for short hospital stayClasses IV and V - Treatment in inpatient settingClass I is 0-50 points - 0.1% mortalityClass II is points - 0.6% mortalityClass III is points - 0.9% mortalityClass IV is points - 9.3% mortalityClass V is greater than 130 points - 27% mortality
42 Severe CAPAdditional criteria that can help determine the need for ICU admission are the presence of 3 minor criteria that compose the definition of severe CAP. Minor criteria are as follows:Respiratory rate greater than or equal to 30 breaths per minuteRatio of PaO2 to fraction of inspired oxygen (ie, PaO2/FiO 2 ) of less than or equal to 250Need for noninvasive ventilation (bilevel positive airway pressure [BiPAP] or continuous positive airway pressure [CPAP])Multilobar infiltratesConfusion/disorientationUremia (BUN greater than or equal to 20 mg/dL)Leukopenia (WBC count <4000 cells/µL)Thrombocytopenia (platelet count <100,000/µL)Hypothermia (core temperature <36°C)Hypotension requiring aggressive fluid resuscitation
43 MedicationThe goals of pharmacotherapy for bacteria pneumonia are to eradicate the infection, reduce morbidity, and prevent complications.
44 Treatment- CAPThe regimens chosen by the IDSA/ATS guidelines mainly rely on macrolides (with or without a beta-lactam) or newer fluoroquinolones for outpatient therapyThe guidelines promote the use of macrolides to provide coverage for both S. pneumoniae and atypical pathogens (particularly, M. pneumoniae and C. pneumoniae), which account for the majority of cases of CAP in ambulatory patients
45 Treatment- CAPIn studies from different regions of the world, atypical pathogens account for 20 to 30 % of cases of CAPRecent use of macrolide antibiotics is considered a risk factor for resistant S pneumoniaeMonotherapy with a macrolide is not recommended for persons who received a macrolide antibiotic in the preceding three months.
46 TreatmentRecommend one of the following oral regimens for HIGH RISK patients:A respiratory fluoroquinoloneCombination therapy with a beta-lactam effective against S. pneumoniae PLUS either a macrolide or DoxycyclineComorbidities or recent antibiotic use: The presence of significant comorbidities (ie, chronic obstructive pulmonary disease [COPD], liver or renal disease, cancer, diabetes, chronic heart disease, alcoholism, asplenia, or immunosuppression).Use of antibiotics within the prior three months, increases the risk of infection with more resistant pathogens.
47 TreatmentIn previously healthy patients with no exposure to antibiotics within the previous 90 days, use the following: Macrolide or doxycyclineIn patients with comorbidities such as chronic disease of the heart, lung, liver, or kidneys; diabetes mellitus; alcoholism; malignancy; immunosuppression (drug- or disease-induced); or use of antimicrobials within the last 90 days, use the following:Respiratory fluoroquinolone or beta-lactam plus macrolide
48 Inpatient TreatmentInpatient empiric antibiotic therapy Inpatient treatment of pneumonia, according to 2009 Joint Commission and the Centers for Medicare and Medicaid Services consensus guidelines, should be given within 6 hours of hospital admission (or in the emergency department if this is where the patient initially presented) and should consist of the following antibiotic regimens :Non-ICU patients (choice of one option)Beta-lactam (IV or IM) plus macrolide (IV or PO)Antipneumococcal quinolone monotherapy (IV or IM) Beta-lactam (IV or IM) plus doxycycline (IV or oral)If patient younger than 65 years with no risk factors for drug-resistant pneumococcus - Macrolide monotherapy (IV or oral)ICU Patients (choice of one option)Beta-lactam (IV) plus macrolide (IV)Beta-lactam (IV) plus antipneumococcal quinolone (IV)If patient has documented beta-lactam allergy - Antipneumococcal quinolone (IV) plus aztreonam (IV)
49 Inpatient TreatmentPatients at increased risk of infection with Pseudomonas (acceptable for both ICU and non-ICU patients) (choice of one option)Antipseudomonal beta-lactam (IV) plus antipseudomonal quinolone (IV; PO in non-ICU only)Antipseudomonal beta-lactam (IV) plus aminoglycoside (IV) plus one of the following:Macrolide (IV)Antipneumococcal quinolone (IV; PO in non-ICU only)If patient has documented beta-lactam allergy - Aztreonam (IV) plus aminoglycoside (IV) plus antipneumococcal quinolone (IV; PO in non-ICU only)
50 MRSAFor suspected infection with methicillin-resistant S aureus (MRSA):Vancomycin or linezolid may be added to the antibiotic regimen until the organism's identity and antibiotic sensitivities are known, at which point the medications can be adjusted accordingly
51 Aspiration pneumonia Aspiration pneumonia empiric therapy The causative organisms in aspiration pneumonia have been noted to be similar to those of CAP or HCAPPatients with severe periodontal disease, putrid sputum, or a history of alcoholism with suspected aspiration pneumonia may be at greater risk of anaerobic infection.One of the following antibiotic regimens is suggested for such patients:Piperacillin-tazobactamImipenemClindamycin or metronidazole plus a respiratory fluoroquinolone plus ceftriaxone
52 Clinical responseClinical response to antibiotic therapy should be evaluated within hours of initiation.With appropriate antibiotic therapy, improvement in the clinical manifestations of pneumonia should be observed in hours.Because of the time required for antibiotics to act, antibiotics should not be changed within the first 72 hours unless marked clinical deterioration occurs.
53 Clinical responseWith pneumococcal pneumonia, the cough usually resolves within 8 days and crackles heard on auscultation clear within 3 weeks.The timing of radiologic resolution of pneumococcal pneumonia varies with patient age and the presence or absence of an underlying lung disease.The chest radiograph usually clears within 4 weeks in patients younger than 50 years without underlying pulmonary disease.Resolution may be delayed for 12 weeks or longer in older individuals and those with underlying lung disease.
54 Clinical response/Failure If patients do not improve within 72 hours, an organism that is not susceptible or is resistant to the initial empiric antibiotic regimen should be considered.Secondary to a complication such as empyema or abscess formation.Broadening the differential diagnosis to include noninfectious etiologies such as malignancies, inflammatory conditions, or congestive heart failure
55 Further Outpatient Care Patients should have a follow-up chest radiograph in approximately 6 weeks to ensure resolution of consolidation.Chest radiograph findings indicating nonresolution of symptoms should raise the consideration of an endobronchial obstruction as a cause of postobstructive pneumonia.
56 Pneumonia in Immunocompromised Pts Smokers, alcoholics, bedridden, immuno-compromised, elderlyCommon still commonS. pneumoMycoplasmaPneumocystis Carinii PneumoniaP. jiroveciiFever, dyspnea, non-prod cough (triad 50%), insidious onset in AIDS, acute in other immunocompromised PtsCXR: bilateral interstitial infiltratesSteroids for hypoxiaTMP-SMZ still first line
57 Prevention Smoking cessation Vaccination per ACIP recommendations InfluenzaInactivated vaccine for people >50 yo, those at risk for influenza compolications, household contacts of high-risk persons and healthcare workersIntranasal live, attenuated vaccine: 5-49yo without chronic underlying dzPneumococcalImmunocompetent ≥ 65 yo, chronic illness and immunocompromised ≤ 64 yo
58 Complications Potential complications include the following: Destruction and fibrosis/organization of lung parenchymaBronchiectasisNecrotizing pneumoniaEmpyemaPulmonary abscessRespiratory failureAcute respiratory distress syndrome ARDSVentilator dependenceDeath