Case #1 Answers:

Answer 1
Yes, this patient most likely has pneumonia.




 

Answer 2
Pneumonia should be considered in the face of a new infiltrate on CXR and some of the following:  fever or hypothermia, new cough with or without sputum production, change in sputum color in patient with chronic cough, or dyspnea.  Physical findings include altered breath sounds and/or localized rales.  Laboratory findings often include leukocytosis.  Symptoms may be subtle in the elderly.  Non-infectious mimics should also be considered, especially if the patient does not improve (i.e., PE, CHF, BOOP, carcinoma or lymphoma).




 

Answer 3
This patient should be admitted for parenteral antibiotic therapy, oxygen and observation. She is at increased risk because of her age, hypoxia, confusion, increased respiratory rate and diastolic hypotension.  She also has associated comorbidities of CHF, DM and dementia.


 

Answer 4
Please see the practice guideline for community acquired pneumonia.  All patients with a diagnosis of pneumonia should be questioned regarding possible TB exposure and whether they have an immunocompromised state.  Respiratory isolation would then be required.


 

Answer 5
Consolidation of the lung parenchyma increases sound transmission and vibration from the vocal cords, trachea and bronchi to the lung parenchyma.  Bronchophony, egophony (E-A) whispered pectoriloquy and increased tactile fremitus should be present.  A pleural effusion decreases sound transmission.  There will be dullness and decreased breath sounds without any of the above.


 

Answer 6
Fifty percent of the time no etiology for pneumonia can be determined. At least one-third of the time the patient is unable to produce an adequate sputum.  Eleven percent of patients hospitalized with community-acquired pneumonia and 20% of cases of pneumococcal pneumonia have positive blood cultures.  Two blood cultures should be obtained from patients hospitalized with community-acquired pneumonia. Pleural fluid evaluation can also be diagnostic. Afebrile bacteremia may occur in up to 20% of cases of pneumonia (especially in the elderly).  An increased RR (>30) can indicate pneumonia in the elderly, as can increased confusion.



 

Answer 7
Expectorated sputum is frequently contaminated by bacteria that colonize the upper airway. Up to 50% of normal adults may carry S. pneumonia in their nasopharynx.  Sputum culture is expensive and often not done properly.  Sensitivity at best is around 50%. The patient should be observed to expectorate deeply.  Only the purulent portion of sputum should be selected for Gram stain and culture.  It should only be examined if it contains >25 PMNS and <10 epithelial cells per low power (not oil-immersion) field (minimal criteria = <25 epithelial cells per low power field). Some studies show that Gram stain sensitivity and specificity for S. pneumonia is 62 and 85 percent, respectively (better than for sputum culture).


 

Answer 8
Respiratory droplet or airborne inhalation (some viruses and tuberculosis); hematogenous (staphylococcus aureus, especially intravenous drug abusers), aspiration and direct inoculation are mechanisms of transmission. Aspiration is the most common mechanism.


 

Answer 9
Streptococcus pneumonia is the most common cause of community acquired pneumonia in which a pathogen is identified, i.e., 40-60% of cases. Up to 35% of respiratory isolates of S. pneumonia are resistant to penicillin (28% of Loyola isolates in 1998, 21% are resistant to erythromycin, 22% are resistant to trimethoprim/sulfamethoxazole).  However, correlation of clinical failures with in vitro testing results are lacking.  Empirical therapy with a beta-lactam antibiotic (ceftriaxone) with or without a macrolide or a fluoroquinolone (levofloxacin, sparfloxacin, grepafloxacin, trovafloxacin or another fluoroquinolone with enhanced activity against S. pneumonia [NOT ciprofloxacin]) alone is appropriate.  Therapy should be altered if susceptibility results indicate that the isolate is resistant to penicillin, ceftriaxone and/or macrolides.  Mycoplasma pneumonia (2-30%, esp. younger persons) or Chlamydia pneumonia (5-15%) may also cause pneumonia – both more common in the outpatient setting. Legionella pneumophila should be considered in the ICU setting or in the elderly, smokers, or the immunocompromised, esp organ transplant recipients. The latter three would be appropriately treated with any of the macrolides, fluoroquinolones or doxycycline.


 

Answer 10
Nosocomial pneumonia occurs in hospitalized patients whose upper respiratory tracts have been colonized by enteric gram-negative bacilli,  Pseudomonas aeruginosa and Staphylococcus aureus.  An antibiotic that covers for gram-negatives and pseudomonas (i.e., Ceftazidime, aztreonam, [with antistaphylococcal drug],  ticarcillin/clavulanate, or imipenem [the latter two cover staphylococcus]) should be used.  Legionella and aspergillus—both more frequent in the immunocompromised--may also occur if the hospital environment is contaminated.

 

Answer 11
Patients, especially elderly, may have slow resolution of CXR infiltrates. The patient generally improves before the CXR. Repeat CXR=s should only be done in the hospital if the patient clinically worsens or for follow-up of a pleural effusion. In order to document resolution and exclude underlying disease such as neoplasm, a repeat CXR may be done in the outpatient setting at 7-12 weeks.



 

Answer 12
S.J. should be given influenza vaccine yearly.  Pneumococcal vaccine should also be given.