CAP

Question 1

Phases in lobar pneumococcal pneumonia

Answer 1

Edema (Congestion)
Red Hepatization
Gray Hepatization
Resolution (Final phase)

Question 2

Initial phase w/ the presence of proteinaceous exudate and bacteria in the alveoli

rarely evident in clinical or autopsy specimens because of the rapid transition to the next phase

Answer 2

EDEMA

Question 3

presence of ERYTHROCYTES in the cellular intraalveolar exudate

neutrophils influx - more important with regard to host defense

bacteria are occasionally seen in pathologic specimens collected during this phase

Answer 3

RED HEPATIZATION

Question 4

no new erythrocytes are extravasating and those already present have been lysed and degraded

NEUTROPHILS - predominant cells

abundant fibrin deposition
(-) bacteria

corresponds with SUCCESSFUL CONTAINMENT OF THE INFECTION and IMPROVEMENT IN GAS EXCHANGE

Answer 4

GRAY HEPATIZATION

Question 5

final phase

MACROPHAGE reappears as the dominant cell type in the alveolar space, and the debris of neutrophils, bacteria, and fibrin has been cleared, as has the inflammatory response

Answer 5

RESOLUTION

Question 6

MC pattern in nosocomial pneumonias

Answer 6

bronchopneumonia pattern

Question 7

TYPICAL BACTERIAL PATHOGENS (CAP)

Answer 7

• S. pneumoniae
• Haemophilus influenzae
• S. aureus
• gram- (-) bacilli - Klebsiella pneumoniae and Pseudomonas aeruginosa

Question 8

ATYPICAL BACTERIAL PATHOGENS

Answer 8

Chlamydia pneumoniae
Legionella species (in inpatients)
Mycoplasma pneumoniae
respiratory viruses - influenza viruses, adenoviruses, human metapneumovirus, and respiratory syncytial viruses

Question 9

Play a significant role only when an episode of aspiration has occurred days to weeks before presentation of pneumonia

Answer 9

Anaerobes

Question 10

MCC of CAP

Answer 10

Strep pneumoniae

Question 11

complicate influenza infection

Answer 11

S. aureus pneumonia

Question 12

RISK FACTORS FOR CAP:

Answer 12

• alcoholism
• asthma
• immunosuppression
• institutionalization
• age of ≥70 years

Question 13

RISK FACTORS FOR PNEUMOCOCCAL PNEUMONIA:

Answer 13

• dementia
• seizure disorders
• heart failure
• cerebrovascular disease (CVD)
• alcoholism
• tobacco smoking
• chronic obstructive pulmonary disease (COPD)
• HIV infection

Question 14

more likely in patients with skin colonization or infection with CA-MRSA

Answer 14

CA-MRSA pneumonia

Question 15

Tend to infect patients who have RECENTLY BEEN HOSPITALIZED and/or RECEIVED ANTIBIOTIC THERAPY or who have comorbidities such as alcoholism, heart failure, or renal failure

Answer 15

Enterobacteriaceae

Question 16

Particular problem in patients with SEVERE STRUCTURAL LUNG DISEASE, such as bronchiectasis, cystic fibrosis, or severe chronic obstructive pulmonary disease (COPD)

Answer 16

P. aeruginosa

Question 17

RISK FACTORS FOR LEGIONELLA INFECTION:

Answer 17

• diabetes
• hematologic malignancy
• cancer
• severe renal disease
• HIV infection
• smoking
• male gender
• recent hotel stay or ship cruise

Question 18

CLINICAL MANIFESTATIONS of CAP

Answer 18

• febrile with tachycardia
• cough - either nonproductive or productive of mucoid, purulent, or blood-tinged sputum
• gross hemoptysis - suggestive of CA-MRSA pneumonia
• involvement of the pleura  pleuritic chest pain
• 20% of patients - GI symptoms such as nausea, vomiting, and/or diarrhea
• OTHER SYMPTOMS - fatigue, headache, myalgias, and arthralgias
• ↑ respiratory rate and use of accessory muscles of respiration – common

Question 19

CLINICAL MANIFESTATIONS of CAP

Answer 19

• febrile with tachycardia
• cough - either nonproductive or productive of mucoid, purulent, or blood-tinged sputum
• gross hemoptysis - suggestive of CA-MRSA pneumonia
• involvement of the pleura –> pleuritic chest pain
• 20% of patients - GI symptoms such as nausea, vomiting, and/or diarrhea
• OTHER SYMPTOMS - fatigue, headache, myalgias, and arthralgias
• ↑ respiratory rate and use of accessory muscles of respiration – common

Question 20

PE findings in CAP

Answer 20

• PALPATION - ↑ or ↓ TACTILE FREMITUS
• PERCUSSION - can vary from DULL to flat, reflecting underlying consolidated lung and pleural fluid, respectively
• AUSCULTATION - CRACKLES, BRONCHIAL BREATH SOUNDS, and PLEURAL FRICTION RUB (possible)

Question 21

DIFFERENTIAL DIAGNOSIS INCLUDES BOTH INFECTIOUS AND NONINFECTIOUS ENTITIES:

Answer 21

acute bronchitis
acute exacerbations of chronic bronchitis
heart failure
pulmonary embolism
hypersensitivity pneumonitis
radiation pneumonitis

Question 22

often necessary to differentiate CAP from other conditions

Answer 22

Chest radiography

Question 23

often necessary to differentiate CAP from other conditions

Answer 23

Chest radiography

pneumatoceles - suggest infection with S. aureus
upper-lobe cavitating lesion - suggests tuberculosis

Question 24

May be of value in a patient with SUSPECTED POSTOBSTRUCTIVE PNEUMONIA caused by a tumor or foreign body or suspected cavitary disease

Answer 24

CT

Question 25

specific views of chest radiograph should be requested?

Answer 25

Standing PA and LATERAL views of the chest in full inspiration comprise the best radiologic evaluation of a patient suspected of having pneumonia. (Grade A)

Question 26

Sputum Gram Stain and Culture

Answer 26

sputum sample: >25 neutrophils/LPF <10 squamous epithelial cells/LPF

Question 27

The standard for diagnosis of respiratory viral infection

Answer 27

PCR of nasopharyngeal swabs

Question 28

CURB-65 criteria - severity-of-illness score

Answer 28

Confusion Urea >7 mmol/L Respiratory rate ≥30/min Blood pressure - systolic ≤90 mmHg/ diastolic ≤60 mmHg Age ≥65 years score of 0 - among whom the 30-day mortality rate is 1.5% - can be treated outside the hospital score of 2 - the 30-day mortality rate is 9.2%, and patients should be admitted to the hospital 0-1 - treat as outpatient 2 - admit patient >3 - consider ICU admission

Question 29

Response to therapy is expected w/ 24-72 hrs of initiating treatment

Answer 29

fever decreases w/n 72 hrs temp normalizes w/n 5 days respiratory signs (tachypnea) return to normal

Question 30

MINIMAL INHIBITORY CONCENTRATION (MIC) CUTOFFS FOR PENICILLIN IN PNEUMONIA

Answer 30

≤2 μg/mL - susceptibility >2–4 μg/mL - intermediate ≥8 μg/mL- resistant

Question 31

RISK FACTORS FOR PENICILLIN-RESISTANT PNEUMOCOCCAL INFECTION:

Answer 31

recent antimicrobial therapy age of <2 years or >65 years attendance at day-care centers recent hospitalization HIV infection

Question 32

The most important risk factor for antibiotic-resistant pneumococcal infection

Answer 32

use of a specific antibiotic w/n the previous 3 months

Question 33

Previously healthy and no antibiotics in past 3 mos

Answer 33

macrolide CLARITHROMYCIN 500 mg PO BID OR AZITHROMYCIN 500 mg PO once then 250 mg qd OR DOXYCYCLINE 100 mg PO BID

Question 34

Comorbidities or antibiotics in past 3 mos: select an alternative from a different class

Answer 34

respiratory fluoroquinolone MOXIFLOXACIN 400 mg PO qd GEMIFLOXACIN 320 mg PO qd LEVOFLOXACIN 750 mg PO qd OR beta lactam preferred high dose AMOXICILLIN 1 g TID OR AMOXICILLIN/CLAVULANATE 2 g BID alternatives CEFTRIAXONE 1-2g IV qd CEFPODOXIME 2OO mg PO bid OR CEFUROXIME 500 mg PO bid PLUS a macrolide

Question 35

Inpatients, NON- ICU

Answer 35

respiratory fluoroquinolone MOXIFLOXACIN 400 mg PO or IV qd LEVOFLOXACIN 750 mg PO or IV qd beta lactam CEFTRIAXONE 1-2g IV qd AMPICILLIN 1-2 g IV q4-q6 CEFOTAXIME 1-2 g q8h ERTAPENEM 1 g IV qd PLUS macrolide ORAL CLARITHROMYCIN or AZITHROMYCIN or IV AZITHROMYCIN once, then 500 mg qd

Question 36

Inpatients, ICU

Answer 36

beta lactam CEFTRIAXONE 2 g IV qd AMPICILLIN-SULBACTAM 2 g IV q8h OR CEFOTAXIME 1-2 g IV q8h PLUS either AZITHROMYCIN or a FLUOROQUINOLONE

Question 37

If Pseudomonas is a consideration

Answer 37

*antipseudomonal beta lactam PIPERACILLIN/TAZOBACTAM 4.5 g IVq6h CEFEPIME 1-2 g IV q12h IMIPENEM 500 mg IV q6h MEROPENEM 1 g IV q8h PLUS either CIPROFLOXACIN 400 mg IV q12h OR LEVOFLOXACIN 750 mg IV qd *above beta lactam PLUS an aminoglycoside AMIKACIN 15 mg/kg qd OR TOBRAMYCIN 1.7 mg/kg qd PLUS AZITHROMYCIN *above beta lactams PLUS aminoglycoside PLUS and antipneumococcal fluoroquinolone

Question 38

If CA-MRSA is a consideration

Answer 38

ADD LINEZOLID 600 mg IV q12h OR VANCOMYCIN 15 mg/kg q12 h initiall w/ adjusted dose PLUS CLINDMYCIN 300 mg q6h

Question 39

Discharge Criteria

Answer 39

during the 24 hrs before discharge temp 36-37.5 pulse <100/min RR 16-25/min SBP >90 mmHg blood O2 saturation >90% functioning GIT (allowing use of oral antibiotics)