ACUTE PULMONARY INFECTIONSZen AhmadMedical Faculty, Sriwijaya University

Case presentationA 55-year-old male with a history of type 2 diabetes, presents with dyspnea, high fever, chills, and productive cough with purulent sputum for 2 days duration. He denies hemoptysis. He has smoked 2 packs of cigarettes a day for the past 20 years and drinks six beers a day. On physical exam he appears acutely ill. His vital signs show a temperature of 40.2C, pulse is 130 beats/minute, RR is 48x/per minute, BP is 113/60.Lungs are dull to percussion and bronchial breath sound heard over the left lower lobe. Chest X-ray showed infiltrates in the left lower lobe.

Key clinical questions

What are the most likely diagnosis in this patient? What are the most likely causative organisms in this patient?What further diagnostic tests are recommended for diagnosis? What are the risk factors for pneumonia Can this patient be treated as an outpatient or should he be admitted?What antibiotic agent would be recommended for this patient?

What are the most likely diagnosis in this patient?

Differential diagnosticPneumoniaTuberculosisAcute bronchitisAcute exacerbation of chronic bronchitisUpper respiratory infectionSinusitisCHFAsthmaLung cancer

Definition of pneumoniaAn acute infection of the lung parenchyma distal to the terminal bronchiole, associated with clinical or radiologic evidence of consolidation of part or parts of one or both lungs.

TerminologyCommunity Acquired Pneumonia versus Nosocomial pneumonia (HAP; VAP, HCAPTypical pneumonia versus atypical pneumoniaMild pneumonia; Moderate pneumonia and Severe pneumoniaLobar pneumonia; Bronchopneumonia and Pleuropneumonia

Clinical manifestationsSudden onset of fever, chillsCoughSputum productionPleuritic chest painDyspnea; TachypneaTachycardiaExtra pulmonary symptoms (nausea, vomiting, malaise, headache, myalgia)

Physical examinationsSign of pulmonary consolidationRestricted movement of the afflicated hemithoraxIncreased fremitus DullnessBronchial breath soundsRales

Clinical manifestations of pneumonia

FeaturesTypicalAtypicalOnsetAgeAppearanceFeverRigorCoughSputumExtra pulmonal Pleuritic chest pain Lung consolidationGram stain WBC, difrential Chest x-raySuddenYoungerToxicHighCommonProductivePurulentUncommonCommonCommonAbundant bacteriaElevated; left shitConsolidationGradual Older Malaise, fatiqueLow gradeUncommonNonproductiveMucoidCommonUncommonUncommonRare bacteriaNormal Patchy, infiltrate

PatientAcute (2 days) Dyspnea, High fever, ChillsProductive cough, purulent sputum T: 39.8CPulse: 130 x/minuteRR: 48x/per minute Percussion: dull Auscultation: bronchial breath sound over the left lower lobeCXR: infiltrates in the left lower lobe.Sudden onset of feverShortness of breath Productive cough, purulent sputumPleuritic chest painTachypnea Restricted movement of the afflicated hemithoraxIncreased fremitus DullnessBronchial breath sounds; RalesCXR: infiltrates (lobar, multilobar, segmental) or pleural effusions Pneumonia

What are the most likely causative organisms in this patient?

Microbial causes of pneumoniaWoodhead M.Medicine International 1995; 31 (9)

CAPNosocomialPneumoniaAtypical PneumoniaS.pneumoniaeH.influenzaeMoraxella catarrhalisS.aureusGram negative bacilliVirusGram negative bacilliS.aureusPseudomonas aerugi-nosaM.pneumoniaeC.pneumoniaeLegionella pneumophila

CAP : Most Common Pathogensexcluding Pneumocystis spp.ICU = intensive care unitFile MJ. Tan JS. Cure open Purn Med 1997. 3(2) 89

Mild (AmbulatoryPatients)Moderate (hospitalized, non ICU)* Severe (ICU)*

S. Pneumoniae M. Pneumoniae H. InfluenzaeC. Pneumoniae VirusesMixed flora (aspiration)S. PneumoniaeM. PneumoniaeC. PneumoniaeH. influenzae Legionella spp Mixed flora(aspiration)S. PneumoniaeS. aureusH. influenzaeGram negative bacilli Legionella spp

Bacterial Pathogens in CAPPersahabatan Hosp. 2000

What further diagnostic tests are recommended for diagnosis?

DiagnosticCXRSputum examination Blood count Blood culturesSerologic studies Thoracentesis Invasive diagnostic proceduresTranstracheal aspirationBronchoscopy or BALDirect needle aspiration

CXRCXR is the most important diagnostic toolNew or progressive pulmonary infiltratesLobus consolidationSegmental consolidationPatchy infiltratePulmonary cavitationsLymphadenopathyPleural effusions

Lobar pneumonia

Location of pneumonia

Sputum examinationThe key factor to identification of the etiology Macroscopic; Gram stain and Sputum cultureLower sensitivity 3050% pathogen could not identifiableFrequently contaminated by MO in the URI

What are the risk factors for pneumonia

Risk factors for pneumonia Extreme of ageUnderlying co-morbid illnessImunocompromiseImpaired mucociliary clearanceAlcoholism; Drug abusersSmokingEndotracheal intubationUpper respiratory infectionImpaired level of consciousnessAn increase in gastric pH (the use of H2 Blocker, Antacid)Neurologic dysfunction

Can this patient be treated as an outpatient or should he be admitted?

Risk Factors used to determine assignment to risk classes II-V

Risk class for patients with CAP

Algorithm pneumonia

What antibiotic agent would be recommended for this patient?

The ideal antibiotic in pneumoniaBactericidal +++Low resistanceCoverage, almost all of respiratory pathogenSingle drug Once-daily doseSafe High respiratory penetrationCost effective

Antibiotics in pneumoniaMacrolideTetracyclineCotrimoxazoleCo-AmoxyclavSultamicillin - lactam (include cephalosporin)FluoroquinoloneAminoglycosideAntipseudomonas

CAP Management IssuesCausative pathogen frequently not foundTypical and atypical found together Therapy must be started early (

Outpatient treatment (IDSA/ATS 2007)

Previously healthy and no use of antimicrobials within the previous 3 months A macrolide Doxycyline Have a comorbid (chronic heart, lung, liver /renal disease; DM; alcoholism; malignancies; asplenia; immunosuppressing conditions ; use of immunosuppressing drugs; use of antimicrobials within the previous 3 months A respiratory fluoroquinolone (moxifloxacin, gemifloxacin, levofloxacin) A b-lactam plus a macrolide (strong recommendation; level I evidence)In regions with a high rate of infection with high-level (MIC _16 mg/mL) macrolide-resistant S. pneumoniae, consider use of alternative agents listed above in (2) for patients without comorbidities

Inpatients, non-ICU treatmentA respiratory fluoroquinolone (strong recommendation; level I evidence)

A b-lactam plus a macrolide (strong recommendation; level I evidence)

Inpatients, ICU treatmentA b-lactam (cefotaxime, ceftriaxone, or ampicillin-sulbactam) plus either azithromycin (level II evidence) or a respiratory fluoroquinolone (level I evidence) (strong recommendation) (for penicillin-allergic patients, a respiratory fluoroquinolone and aztreonam are recommended)

Incorrect diagnosisHost issuesPathogen issuesFailure of empirical treatmentCorrect diagnosisDrug issuesBacterialNonbacterialError in drug selectionError in dose/routeComplianceAdverse drug reactionLocal factorInadequate host responseComplication

Prognostic factorsExtremes of ageInappropriate antibiotic therapyShockInvolvement of 1 lobePeripheral WBC count 5000/lPresence of associated disorders (eg: cirhosis; heart/renal failure)Development of extrapulmonary complications (eg: meningitis, endocarditis)

Mortality in patients with CAPFine et al. JAMA 1995;274: 134-141

Study FocusPatients Mortality (%)Hospitalized and ambulatoryHospitalized onlyElderlyBacteriemicNursing homeIntensive Care Unit5.113.617.619.630.836.5

ComplicationsAcute respiratory distress syndromeLung abscessRenal failure Septic shockPleural effusions/EmpyemaBacteriemia (Septic arthritis; Endocarditis; Meningitis; Peritonitis; Endopthalmitis.