Risk Factors for CAP (pneumococcus): Cig smoking, Alcoholism, Asthma, COPD, immunosuppression, AIDS, ChemoTx, Institutionalized - prison, military, Dementia, sz d/o, stroke, CHF

Risk Factors for CA-MRSA: Native american, homeless youth, MSM, prison inmates, military, child care centers, atheletes - wreslters.

Enterobacteriaceae and Pseudomonas: Pts who had received recently received Abx Tx and corticosteroids, or been hospitalized or have comorbidities such as alcoholism, heart failure, or renal failure.

Legionella infection: DM, hematologic malignancy, cancer, severe renal disease, HIV infection, smoking, male gender, and a recent stay or ship cruise.

Severity/Morbidity:

• Older Pts, DM, CAD, home O2 = admit.

• PSI (Pneumonia severity Index), prognostic model used to identify pts at low risk of dying. Less practical in a busy ER setting, because it has 20 variables.

• CURB-65: severity-of-illness score.

  • Aassign 1 point to each. Confusion, Uremia (BUN >7 mmol/L); RR: >30 or more; BP: SBP <90 or lower, or DPB <60 or lower, and >65 yr or more of age.

    • Score 2: admit

    • Score 3: admit in ICU

  • High scores predict higher mortality

• ATS and IDSA have major and minor criteria - although not validated, can be used as a guide

  • Major Criteria: Need for vasopressors or mechanical ventilation.

  • Minor Criteria: Non-invasive ventilation, RR >30, multilobar infiltrates, hypotension that requires aggressive fluid resuscitation, hypothermia, thrombocytopenia, leukopenia, delirium, uremia, PaO2/FiO2 <250, and hypoglycemia in a nondiabetic patient.

  • Presence of 1 major and/or 3 minor criteria likely warrants admission to an ICU.

Clinical features:

• CAP can vary from sudden onset to indolent presentations and from mild to fatal in severity.

• Constitutional and lung symptoms: HA, fatigue, malaise, myalgias, and arthralgias

• Fever, chills, sweats, cough +/- productive of mucoid, purulent or blood-tinged sputum, tachypnea and tachycardia. Pleuritic CP.

• 20% have GI sx: abdominal pain, nausea, vomiting, diarrhea.

DDx: acute bronchitis, acute exacerbation of chronic bronchitis, HF, PE, XRT pneumonitis, hypersensitivity pneumonitis, and connective tissue disease involving lungs.

HEALTH CARE-ASSOCIATED PNEUMONIA

• HAP

• VAP (VENTILATOR-ASSOCIATED PNEUMONIA

VAP:

Microbiologic Causes of VAP

Tx:

Empirical ABx Tx of CAP:

• Outpatients: previously healthy and no Abx in past 3 months

  • A macrloide (clarithromycin), 500 mg PO bid or azithromycin, 500 mg PO once, then 250 mg PO daily, OR

  • Doxycycline, 100 mg PO bid as alternative to macrolide.

• Comorbidities or Abx in past 3 mo: select an alternative from a different class

  • Fluoroquinolone, moxifloxacin, 400 mg PO daily, gemifloxacin, 320 mg PO daily, levofloxacin, 750 mg PO daily, OR

  • B-lactam, amoxicillin, 1 g PO tid, or amoxicillin/clavulanate, 2 g PO bid; alternatives: ceftriaxone, 1 - 2 g IV daily, cefpodoxime, 200 mg PO bid, cefuroxime, 500 mg PO bid + a macrolide or doxycycline, 100 mg PO bid

  • In regions with a high rate of "high-level" penumococcal macrolide resistance (MICs of >16 mcg/mL in 25% of isolates), consider doxycycline 100 mg PO bid.

• Inpatients, non-ICU

  • Moxifloxacin, 400 mg PO or IV daily; gemifloxacin, 320 mg PO daily; levofloxacin, 750 mg PO or IV daily.

  • Cefotaxime, 1 - 2 g IV q8h, ceftriaxone, 1 - 2 g IV daily, ampicillin, 1 - 2 gm IV q4 - 6hr, ertapenem, 1 gm IV daily in selected pts + a macrolide, clarithromycin or azithromycin or azithromycin, 1 g IV once, then 500 mg PO daily. Doxycycline, 100 mg IV q12hr, can be given as alternative to macrolide.

• Inpatients, ICU

  • Cefotaxime, 1 - 2 g IV q8h, ceftriaxone, 2 g IV daily, ampicillin-sulbactam, 2 g IV q8h + Azithromycin or a fluoroquinolone (as listed for non-ICU)

• Special concerns:

  • If Pseudomonas is a consideration

    • Piperacillin/tazobactam, 4.5 gm IV q6hr, cefepime, 1 - 2 gm IV q12 hr, imipenem, 500 mg IV q6 hr, meropenem, 1 g IV q8 hr + either ciprofloxacin, 400 mg IV q12hr or levofloxacin, 750 mg IV daily.

    • The above beta-lactams + amikacin, 15 mg/kg daily or tobramycin, 1.7 mg/kg daily and azithromycin.

  • If CA-MRSA is a consideration:

    • Linezolid, 600 mg IV q12hr or vancomycin, 1 gm IV q12hr

• General Considerations:

  • Treatment of uncomplicated pneumonia is 5 days. Long term Tx in complicated cases, bacteremia, disseminated inf, P. aeruigonsa, MRSA

  • Failure to improve in 3 days or less, needs reassessment.

  • Adequate hydration, O2, assisted vent if needed.

  • Aspiration precautions

  • Pts with severe CAP who remain hypotensive despite aggressive fluid resuscitation may have adrenal insufficiency and may respond to glucocorticoid tx.

  • Immunomodulatory tx, drotrecogin alfa (activated) should be considered in CAP Pts with persistent septic shock, especially if inf is due to S. pneumoniae.

Complications:

• Respiratory failure, shock, MOD, DIC, lung abscess, pleural effusion, parapneumonic effusion, metastatic inf/septic emboli - brain abscess, endophthalmitis, endocarditis.

• If pleural fluid has pH <7, glucose <2.2 mmol/L, LDH >1000 U/L or if bacteria are seen or cultured, then fluid should be drained - a chest tube is usually required.

Discharge Goals:

• D/c after fever and leukocytosis has resolved, Pt. is afebrile for 48 - 72 hrs, O2 saturation while breathing RA is >92%, eating PO. Sometimes it is possible to arrange for home O2, ABx Tx, with close OP f/up, but it depends in part on the particular Pt and whether or not insurance will cover HHC services.

• All D/c Pt. should receive vaccination against influenza if it is during the flu season. Pts >65 yrs or with comorbidities such as lung disease, DM, immunosuppression should receive the adult pneumonia vaccine.

• F/up with PCP in 1 - 2 wk, following d/c.

F/up:

• Fever and leukocytosis usually resolve in 2 - 4 days in uncomplicated CAP.

• Physical findings last longer.

• CXR are slowest to resolve, takes 4 - 12 weeks to clear. F/up CXR can be done ~4 - 6 wks post d/c. If relapse or recurrence is documented, particularly in the same lung segment, then think of neoplasm.

HCAP: HAP and VAP

Empirical ABx Tx for HCAP