Tuesday Conference Approach to Community Acquired Pneumonia

1. Tuesday ConferenceApproach to Community Acquired Pneumonia Selim Krim, MD Assistant Professor TTUHSC

2. Case 1 A 62-year-old white male presents complaining of cough, fever, and difficulty breathing, which developed during the night. He has no symptoms of rhinorrhea, sore throat, or earache. He is not a smoker and has no history of asthma or recent antibiotic use. He is a business executive who travels extensively and just returned from California.

3. Case 1 On physical examination, he appears flushed but otherwise alert and oriented. He is 5-11, 180 lbs and has a blood pressure of 110/70 mmHg, a heart rate of 90 beats per minute, a respiratory rate of 24 breaths per minute, and a body temperature of 39 ºC. Lung sounds reveal a mild dullness in right base, no increased tympany, and coarse breath sounds with mild rales in right posterior lung base. He is not wheezing. The rest of his exam is normal.

4. Based on your history and physical exam what is your diagnosis?

5. Diagnosis of Pneumonia Signs and symptoms • Fever or hypothermia, cough with or without sputum, dyspnea, chest discomfort, sweats, or rigors • Atypical pneumonia associated with headaches, diarrhea, nonexudative pharyngitis, bullous myringitis, slow onset, myalgias • Physical exam may reveal fever, tachypnea, tachycardia. • Lung exam; increased tactile fremitus, dullness to percussion, decreased breath sounds, presence of rales or crackles

6. MCQ 3 • What is the next most important step in this patient's care? • Empiric therapy with a fluoroquinolone • Chest x-ray • Sputum culture • Hospitalization • CBC, glucose, BUN, Na tests

7. Diagnostic tests • Chest x-ray essential (AP and Lateral) • Patchy airspace infiltrates (Mycoplasma) • Lobar or segmental consolidation (w/air bronchogram) (Pneumococcal) • Diffuse alveolar or interstitial infiltrates (viral or Mycoplasma and other)

8. Epidemiology

9. MCQ 1 • Which of the following statements is not true about community-acquired pneumonia? • More than 4 million cases of community-acquired pneumonia (CAP) occur each year • Less than 10% of patients with CAP need hospitalization • No causative agent is identified in 30% to 50%of cases • Streptococcus pneumoniae is the most commonly identified organism • Nursing home-acquired pneumonias are usually caused by the same organisms as community acquired pneumonias but with increased numbers of S aureus and gram-negative organisms

10. MCQ 2 • Streptococcus pneumoniae is identified in up to what percentage of community-acquired pneumonia cases? • 40% • 50% • 60% • 70% • 80%

11. Identified Pathogens in Community-acquired Pneumonia Pathogen Percentage • Streptococcus pneumoniae 20-60% • Haemophilus influenzae 3-10% • Staphylococcus aureus 3-5% • Gram-negative bacilli 3-10% • Legionella species 2-8% • Mycoplasma pneumoniae 1-6% • Chlamydia pneumoniae 4-6% • Viruses 2-15% • Aspiration 6-10% • Others 3-5%

12. MCQ 4 • What is the most likely pathogenic mechanism in this patient's pneumonia? • Direct inoculation • Aspiration of oropharyngeal contents • Hematogenous deposition • Reactivation • Inhalation of infectious particles

13. Pathogenetic mechanisms in Pneumonia • Inhalation of infectious particles Common • Aspiration of oropharyngeal or gastric content Common • Hematogenous deposition Uncommon • Invasion from infection in contiguous structures Rare • Direct inoculation Less common • Reactivation More common in Immunocompromised hosts

14. Case 1 A 62-year-old white male presents complaining of cough, fever, and difficulty breathing, which developed during the night. He has no symptoms of rhinorrhea, sore throat, or earache. He is not a smoker and has no history of asthma or recent antibiotic use. He is a business executive who travels extensively and just returned from California.

15. Case 1 On physical examination, he appears flushed but otherwise alert and oriented. He is 5-11, 180 lbs and has a blood pressure of 110/70 mmHg, a heart rate of 90 beats per minute, a respiratory rate of 24 breaths per minute, and a body temperature of 39 ºC. Lung sounds reveal a mild dullness in right base, no increased tympany, and coarse breath sounds with mild rales in right posterior lung base. He is not wheezing. The rest of his exam is normal.

16. Should this patient be admitted?

17. RISK STRATIFICATION Pneumonia Severity Index Calculator

18. Risk of 30 d Mortality By Point Total Risk Class Point score Mortality% • I   0.1 • II < 70 0.6 • III 71-90 2.8 • IV 91-130 8.2 • V > 130 29.2

19. Case 1 (Part 2) Empiric therapy with an oral macrolide was prescribed, and the patient was sent home. Two days later, he presents at the emergency room with shaking chills and fever, increasingly productive cough, and difficulty breathing. His vital signs are as follow: BP 110/60 mmHg, body temperature 40.5° C, pulse rate 126 beats/min, and respiration rate 28 breaths/min. He is alert and oriented. His exam again reveals rales and dullness in the right lower posterior lung fields without wheezing. Chest x-ray shows a focal infiltrate in the right lower lung and a small pleural effusion.

20. MCQ 5 • After recalculating your PSI , what is this patient's 30-day mortality risk factor classification and should he be admitted? • I • II • III • IV • V

21. RISK STRATIFICATION Pneumonia Severity Index Calculator

22. Risk of 30 d Mortality By Point Total Risk Class Point score Mortality% • I   0.1 • II < 70 0.6 • III 71-90 2.8 • IV 91-130 8.2 • V > 130 29.2

23. MCQ 6 • Which of the following findings would NOT further raise his risk factor score (and increase his 30-day mortality risk)? • Serum urea nitrogen > 30 mg/dL • Confusion • Arterial blood pH below 7.35 • Elevated white blood cell count (>15,000) • Na below 130 mEq/L

24. MCQ 7 • Which statement is NOT correct concerning this patient? • Because initial empiric outpatient therapy failed, the possibility of pulmonary emboli or malignancy constitutes a majority • He should be hospitalized and given empiric intravenous antibiotic therapy with fluoroquinolone alone • Extensive serology testing should be conducted for HIV, Mycoplasma and Chlamydia species, SARS, and influenza A and B on specimens obtained by bronchoscopy • Sputum gram-stain and cultures as well as blood cultures need to be obtained after hospital admission

25. Which test to order?

26. MCQ 8 • Pathogen-specific treatment with a macrolide or doxycycline in community-acquired pneumonia is recommended with which organism? • Staphylococcus aureus • Mycoplasma pneumoniae • Pseudomonas aeruginosa • Influenza A • Streptococcus pneumoniae

27. How would you treat this patient?

30. Case 1 (Part 3) • Patient is admitted to the hospital and treated with IV ciprofloxacin. After 3 days, he is still febrile and in need of oxygen supplementation, but he is alert and eating on his own. Blood and sputum cultures are negative.

31. MCQ 9 • Which of the following would be the next best step? • Change to oral antibiotics based on presumed S pneumoniae • Add zanamivir for possible influenza A or B • Direct fluorescent antibody staining by nasal swab for viruses or sputum for Legionella • Fiberoptic bronchoscopy with lavage and transbronchial biopsy • Add vancomycin with or without rifampin

32. Would you consider discharging your patient at this point?

33. Discharge Criteria • Candidates for discharge should have no more than one of the following poor prognostic indicators: • Temperature > 37.8 degrees Celsius • Pulse > 100 beats per minute • Respiratory rate > 24 per minute • Systolic blood pressure < 90 mmHg • Oxygen saturation < 90 percent • Inability to maintain oral intake

34. Key Points • Community-acquired pneumonia can be treated empirically with oral antibiotics in the outpatient setting in patients with class I or II PORT category risk factor stratification. • Patients younger than age 50 who have no comorbid health problems and who present with minimal signs and symptoms of possible pneumonia can safely be treated without the need for further testing. • A macrolide or doxycycline is the treatment of choice for healthy patients younger than age 60 who have presumed pneumonia. Fluoroquinolones are not recommended in these patients because of increasing problems with antibiotic resistance.

35. Key Points • In all patients in whom pneumonia is suspected, a chest x-ray should be ordered to provide diagnostic evidence with which to distinguish different patterns of infiltrates. • The need for in-patient care can be determined by professional judgment, based on the patient's signs and symptoms; however, a risk factor calculation can be helpful in determining those with high predicted mortality. • Obtaining blood cultures within 24 hours of admission and starting antibiotics within 4 hours of admission have been shown to reduce 30-day mortality and are considered quality indicators.

36. Key Points • Because 30% to 50% of patients with community-acquired pneumonia never have a pathogen identified, it is recommended that empiric therapy selection be based on presumed organisms and their sensitivities, history of exposure, other comorbid health conditions, and x-ray findings. • Aggressive testing including cultures, serology testing, and other rapid assays to determine the causative pathogen are appropriate for most inpatients. More invasive testing, including bronchoscopy, should be reserved for deteriorating patients in whom no etiology has been determined.

37. Thank You