ACUTE BRONCHITIS:
Definition:Â
- Infection of trachea and bronchi due to spread of URI or exposure to irritants
MCC:
- Non-smokers: Mycoplasma pneumoniae (Dx: high agglutinin titer)
- Smokers: S. pneumoniae + H. influenza
Clinical features:Â
- Productive cough, sore throat, fever, wheeze
CXR:
- Mild congestion
Treatment:Â
- Most cases are viral -> self-limited, if suspecting bacteria -> give abx
PNEUMONIA:
Definition:Â
Infection of the bronchoalveolar tree
Types:
a. Community acquired pneumonia (CAP):
- From the community or w\ in the first 72 hrs of hospitalization
- MCC pathogen: Pneumococcus
b. Nosocomial pneumonia:
- After the first 72 hrs of hospitalization
- MCC pathogen: Gram neg (E. coli, pseudomonas) and Staph aureus
Diagnosis:
CXR:
- PA + lateral. Sensitive (if neg -> don’t treat)
- Once URI is excluded, CXR is done to differentiate between acute bronchitis and pneumonia, which are both LRI
- False negative -> neutropenia, dehydration, PCP infection, early ds
- Changes after treatment take up to 6 weeks
Sputum:
- Gram stain: in all pts
- Culture: in pts requiring hospitalization
- Acid-fast stain -> for mycobacterium
- Silver stain -> for fungi (PCP) in HIV\immunocompromised pts
- Legionella -> urinary Ag assay. Very sensitive, remains for wks even after treatment
- PCP -> Broncho-alveolar lavage
- Mycoplasma -> cold agglutins
- “Consider” two Pretreatment blood cultures from diff sites
Thoracentesis:
- PH < 7.2: empyema -> chest tube drainage
- LDH > 0.6 or protein > 0.5: exudate; infection or cancer
Treatment:
Outpatients:
- Continue treatment for 5 days. Don’t stop until pt is afebrile for 48 hrs
- < 60 yo -> 1st Macrolides (azithromycin or clarithromycin) or doxycycline. 2nd fluoroquinolone
- > 60 yo OR those treated w\ antibiotic in the last 3 mo -> 1st fluoroquinolone (levofloxacin, moxifloxacin). 2nd third-gen cephalosporin
Hospitalized:
- Fluoroquinolone
- Third-gen cephalosporin + macrolides (ceftriaxone + azithromycin)
HAP: tailored towards gram-neg rods
- Cefrazidime or cefepime (cephalosporin w\ pseudomonal coverage)
- Carbapenems: imipenem
- Piperacillin\tazobactam
When to admit?
Based on pneumonia severity (index, CURB65)
- Hypotension (sys <90)
- RR > 30, or pO2 <60 mmHg, PH <7.35
- BUN > 30 mg\dL, Na < 130 mmol\L, glucose > 250 mg\dL
- Pulse > 125
- Confusion
- Temprature > 40 c
- > 65 yo, or w\ comorbid: ca, COPD, CHF, renal failure, liver ds
Pneumococcal vaccinations given to?
- Pts > 65 yo
- Younger pt w\ risk: CSF leak, cochlear implant, sickle cell, DM, alcoholic cirrhosis, asplenic, pulmn\cardiac ds
- NOT healthcare workers
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Complications:
- Pleural effusion (50%). If significant (>1cm on lateral) -> thoracocentesis
- Pleural empyema (2% of CAP, 7% hospitalized CAP)
- Acute respiratory failure
 Random notes:
- Nursing home residents -> nosocomial pathogens + prefer upper lobes (Pseudomonas)
- Legionella –> transplant recipients, renal failure pts, chronic lung ds, smokers: present w\ GI sx + hyponatremia
Download the PDF version: here
References:
- Step up to medicine
- Master the boards
- Kaplan step 2 videos