Community-Acquired Pneumonia acquired pneumonia as: a. An ailment - PDF document

In 1898, William Osler described community- Community-Acquired Pneumonia acquired pneumonia as:  a. An ailment that often leads to suffocation and death.  b. A friend of the aged.  c. A common and mortal disease which can be diagnosed by simple observation and percussion of the chest. Rachel Chin, MD University of California, San Francisco  d. Bad. Really really bad. San Francisco General Hospital In 1898, William Osler described community- Roadmap acquired pneumonia as:  a. An ailment that often leads to suffocation  Background and death.  Etiology  b. A friend of the aged.  Diagnosis  c. A common and mortal disease which can be  Treatment diagnosed by simple observation and  Prevention percussion of the chest.  d. Bad. Really really bad. CAP: Background - Epidemiology CAP: Symptom Frequency  5 million cases/year in the US  Cough 90%  80% of CAP is treated outpatient  Dyspnea 66%  6 th leading cause of death  Sputum 66%  Inpatient mortality 10-35%  Pleuritic chest pain 50%  Outpatient mortality <1% But, only 4% of all visits for cough turn out to be pneumonia…. Halm EA, Teirstein AS. N Engl J Med 2002;347(25):2039 .

Clinical Presentation: Geriatrics Roadmap  Less “classic” presentations  Background  Etiology  10% have NONE of the classic signs or symptoms  Diagnosis  Up to 40% will not have fever  Treatment  Up to 45% will have altered mental status  Prevention Mehr DR, et al. J Fam Prac 2001;50(11);1101 Riquelme R, et al. Am J Respir Crit Care Med 1997;156:1908 Host Defenses “Typical” vs “Atypical”  Mechanical factors  Antimicrobial factors  Classic teaching is not supported by the literature  IgA (and IgG, IgM)  Nasal hair  Complement  Some general trends  Turbinates  Alveolar lining fluid  S. pneumoniae in older pts, co-morbidities  Mucocilliary apparatus  Cytokines (TNF, IL-1, IL-  Mycoplasma in patients < 50 years old 8, others)  Cough  Macrophages  But – no history, exam, laboratory or  Airway branching radiographic features predict organism  PMNs  Lymphocytes Typical vs. Atypical Etiology  Typical  Atypical  Streptococcus pneumoniae 20-60%  Haemophilus influenzae 3-10%  Visible on Gram stain,  Not visible on Gram stain, grows in routine culture special culture techniques  Mycoplasma pneumoniae up to 10%  Chlamydophila pneumoniae up to 10%  Susceptible to beta  Not treated with beta lactams lactams  Legionella up to 10%  S. pneumoniae , H.  M. pneumoniae , C.  Enteric Gram negative rods up to 10% pneumoniae , Legionella influenzae  Staphylococcus aureus up to 10% X X  Viruses up to 10%  No etiologic agent 20-70%

Community Acquired Pneumonia Roadmap (CAP): definition  At least 2 new symptoms  Background Fever or hypothermia Cough  Etiology Rigors and/or diaphoresis Chest pain  Diagnosis Sputum production or color change Dyspnea  New infiltrate on chest x-ray and/or  Treatment abnormal chest exam  Prevention  No hospitalization or other nursing facility prior to symptom onset Sputum for CAP Diagnosis  Chest radiograph – needed in all cases?  Complicated and controversial  Avoid over-treatment with antibiotics  Simple, inexpensive, specific for  Differentiate from other conditions pneumococcus  Specific etiology, e.g. tuberculosis  Problems include:  Co-existing conditions, such as lung mass or pleural effusion  Up to 30% could not produce adequate sputum  Evaluate severity, e.g. multilobar  Good quality available in only 14%  Unfortunately, chest physical exam not sensitive or  Most don’t narrow antibiotics specific and significant variation between observers Sputum for CAP Blood Cultures in CAP  In general, sputum cultures are not indicated in  Limitations the management of outpatient CAP  Positive in < 10% of cases  For inpatient CAP, sputum is indicated:  High percentage of contaminants  Culture change antibiotics in < 5% of patients  High-quality specimen, right to the lab  Costly  ICU, Cavitary infiltrates, Underlying lung disease Metersky ML, et al. Am J Respir Crit Care Med 2004;169 (3):342-7

Diagnostic testing for CAP Blood Cultures in CAP  In general, blood cultures are not indicated in the  Get the CXR (esp. outpatient) management of outpatient CAP.  Blood and sputum cultures generally  For inpatient CAP, blood cultures are optional unless discouraged in outpatient CAP clear risk factors for positive blood cultures:  General trend away from blood and sputum in  ICU, severe liver disease, cavitary infiltrates, pleural non-ICU patients admitted with CAP effusion IDSA/ATS Guidelines. CID. 2007;44:S27-72. Other diagnostic tests in CAP Microbiological Investigation - Inpatients  Pneumococcal urinary antigen  Consider evaluation for Legionella  Rapid test, specificity > 90% ( but specificity poor in  Urinary antigen test for L. pneumophila serogroup 1 (70%) children, possibly due to carriage)  Culture with selective media  If positive, tx for pneumococcal disease  May not reduce antibiotic spectrum  -- > 70% with no change Sorde R, et al. Arch Intern Med. 2011;171:166. The future in CAP - biomarkers Microbiological Investigation - Inpatients  Other studies as clinically indicated, e.g. influenza  Procalcitonin: precursor of calcitonin  M. pneumoniae serologic studies can be considered but are uncommon in routine practice (mostly IgM-specific assays)  No hormonal activity  Serologic studies of Chlamydophila largely for epidemiology  Inflammatory marker  For C. pneumoniae , IgM is available, titer > 1:16 considered  Increased in sepsis, bacterial infection positive  Bronchoscopy perhaps for fulminant course, unresponsive to conventional therapy, or for specific pathogens (e.g. M. tuberculosis , Pneumocystis )

Case # 1 Bacterial Pneumonia  28 year old HIV positive man complains of  Clinical presentation productive cough for 1 week and fevers. CD4  CD4 cell count: any 800. He has no history of Opportunistic  Symptoms: Fever, SOB, chest pain, productive Infection (OI ’ s) and takes no medicines. O 2 cough w/ purulent sputum saturation 93%. CXR pending.  Duration: 3-5 days  Signs: Focal lung findings  Labs: WBC often (relatively) elevated Case # 1  28 year old HIV positive man complains of dry  Returns 10 days later with diffuse pneumonia cough for 2-4 weeks and fevers. He has no and goes to the ICU with the diagnosis of PCP. history of Opportunistic Infection (OI ’ s) and  What could have changed this management? takes no medicines. CD4 150. Normal Vital signs. O 2 saturation 95%. CXR clear.  What was the stage of the HIV infection? What is the Stage of HIV infection?  Pulmonary disease is one of the most common  Defined by CD4 count: HIV-related emergencies  Early: CD4 > 500/mm 3  PCP is the leading AIDS-defining condition in  Intermediate: CD4 200-500/mm 3 the United States  Late: CD4 < 200/mm 3  Pneumocystis jiroveci ( “ yee row vet zee ” -  ?Very Late: CD4 < 50/mm 3 formerly carinii) pneumonia

Treatment P neumo c ystis jiroveci P neumonia  Clinical presentation  Trimethoprim-sulfamethoxazole  Clindamycin + Primaquine  CD4 cell count ≤ 200 cells/mm 3  Trimethoprim + Dapsone  Symptoms: fever, DOE, dry cough , fatigue  Atovaquone  Duration: >2-4 weeks  Pentamidine  Signs: Nonspecific  Labs: Serum LDH often elevated  Treat for 21 days followed by prophylaxis  Steroids 40 mg PO BID if Pa02 < 70 mm Hg Roadmap A healthy 48 yo woman who was recently treated for cystitis (1 month ago) with cipro presents with fever, cough, sob. CXR reveals RLL infultrate and you dx CAP and decide to treat as an outpatient.  Background Which of the following is the best treatment regimen?  Etiology a. Levofloxacin PO  Diagnosis b. Azithromycin PO  Treatment c. Ertapenem IV  Prevention d. Augmentin PO and Azithromycin PO e. Doxycycline PO and penicillin PO Etiology of CAP Treatment Principle #1 Outpatients (mild) Non-ICU Inpatients ICU inpatient Outpatients (mild) S pneumoniae S pneumoniae S pneumoniae S pneumoniae M pneumoniae M pneumoniae Legionella spp M pneumoniae Must cover all these organisms H influenzae H influenzae C pneumoniae H influenzae C pneumoniae H influenzae GNRs C pneumoniae Resp viruses Legionella spp S Aureus Resp viruses Resp viruses File TM. Lancet 2003;362:1991.