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Bronchitis, Pneumonia, and Pleural Empyema
Katay Bouttamy DOTintinalli Chapter 63
Acute Bronchitis Definition: an acute respiratory
tract infection with cough being the predominant feature
Usually lasts 1 to 3 weeks, peaks between October and March
Viruses cause the vast majority of cases: Influenza A and B, parainfluenza, and RSV are the most common
Acute Bronchitis Bordetella pertussis, Mycoplasma
pneumoniae, Chlamydia pneumoniae, and Legionella species are reported in 5-25% of cases
Clinical features: cough and wheezing are the strongest positive predictors, less than 10% of patients are febrile
Acute Bronchitis Diagnosis: (1) acute cough less than 1-2
weeks (2) no prior lung disease (3) no auscultatory abnormalities that suggest pneumonia
Treatment: studies have failed to show significant improvement with Abx therapy and at best may decrease duration of cough, decrease purulent sputum production and return patients to work < 1 day each
Acute Exacerbation of Chronic Bronchitis Two-thirds are bacterial in origin (H. flu,
Strep pneumo, M. Catarrhalis) High risk patients are the elderly and those
with poor lung function and with comorbid conditions
Characterized by increased dyspnea, increased cough and sputum production and purulence with underlying COPD
Treatment includes doxycycline, extended spectrum cephalosporin, macrolide, augmentin or fluoroquinolone
Pneumonia CAP is 6th leading cause of death Studies of both inpatients and
outpatients with CAP fail to identify a specific pathogen in 40-60% of patients but when found pneumococcus is still the most common
Pneumonia Typical presentation of
pneumococcal pneumonia is sudden onset of fever, rigors, dyspnea, bloody sputum production, chest pain, tachycardia, tachypnea and abnormal findings on lung exam
Some of the atypicals are associated with headache and GI illness
Other bacterial pneumonia Staph aureus is a consideration in
patients with chronic lung disease, laryngeal CA, immunosuppressed patients, NH patients; chest Xray usually shows extensive disease with empyema, effusion or multiple areas of infiltrate
Other bacterial pneumonia Klebsiella occurs in patients at risk at
aspiration, alcoholics, elderly and other patients with chronic disease; may develop abscesses but often have lobar infiltrates
Pseudomonas not a typical cause of CAP and usually associated in patients who have prolonged hospitalization, have been on broad-spectrum Abx, high-dose steroids, structural lung disease or NH patients
Other bacterial pneumonia H. flu seen in elderly and should be
considered in patients with COPD, sickle cell disease or immunocompromised disorders
M. catarrhalis similar to H. flu
Atypical Pneumonia Legionella should be considered in
cigarette smokers, persons with COPD, transplant patients and immunosuppressed patients; commonly complicated by GI symptoms including abdominal pain, vomiting and diarrhea
Chlamydia usually causes a mild subacute illness with sore throat, mild fever, and NP cough
Atypical Pneumonia Mycoplasma occurs year round
and causes a subacute respiratory illness and occasionally causes extrapulmonary symptoms including bullous myringitis, rash, neurologic symptoms, arthritis, hematologic abnormalities and rarely renal failure
Pneumonia in Special populations Alcoholics: Strep pneumo still most
common but Klebsiella and H. flu are important pathogens
Diabetics: patients between 25-64 are 4 times more likely to have pneumonia
Pregnancy: more likely to experience preterm labor, preterm delivery and deliver a low birthweight infant
Pneumonia in Special populations Elderly: 3 times more likely to have
pneumococcal bacteremia, mortality is 3-5 times greater than those younger than 65, have atypical symptoms (afebrile, c/o weakness, falling, GI symptoms, delirium, confusion) and up to 1/3 will not manifest leukocytosis
Nursing-Home acquired Pneumonia Patients are less likely to have productive
cough or pleuritic chest pain and more likely to be confused and have poorer functional status and more severe disease
8 independent predictors of pneumonia: increased pulse, RR>30, T>100.4, somnalence or decreased alertness, acute confusion, lung crackles, absence of wheezes and increased WBC
Treatment Outpatient: doxycycline, newer macrolide
or fluoroquinolone Hospitalized: evidence indicates that
early administration (within 8 hrs of presentation) leads to lower mortality rate and hospital stay, therapy should be initiated with 2-3rd generation cephalosporin or PCN plus beta-lactamase inhibitor, with a macrolide. Coverage can also be provided with newer fluoroquinolone.
Disposition Estimated 75% of patients with CAP
do not require hospitalization, many factors influence prognosis and outcome
Fine’s prediction rules can be used to estimate risk of death and ICU placement (does not include patients from NH or hospital setting and HIV patients)
Disposition PSI score of I, II, III generally have low
mortality and mortality jumps between III and IV
Forest study looked at clinical judgement vs PSI alone to determine need for hospitalization: many people with low PSI need to be admitted for other reasons (noncompliance, inability to eat or drink, unmet social needs, failed outpatient Tx)
Empyema Pleural effusions are present on X-
ray of 20-60% of patients with bacterial pneumonia and often resolve with antibiotic therapy
Risk factors: aspiration, immunocompromised patients with gram neg bacteria, fungal infections, TB or malignancy
Empyema Exudative stage: free flowing pleural fluid,
very amenable to treatment with closed tube drainage
Fibrinopurulent stage: formation of fibrin strands through the pleural fluid resulting in loculations, makes adequate drainage with single chest tube unlikely
Organizational stage: fibrosis is much more extensive forming a pleural peel that restricts expansion even if fluid can be evacuated
Empyema Decub films will be helpful in
determining if fluid is free flowing or loculated
Pleural fluid that is gross pus with positive cultures or gram stain is considered empyema along with other findings: pH<7.1, glucose<40 and LDH>1000
Empyema Treatment: drainage of pus by
chest tube, reexpansion of lung and eradication of the infection. Treatment of organizational stage requires surgical intervention with removal of the fibrous peel
Questions 1. All are true of Acute Bronchitis
except: a. Peaks from October and Marchb. Viruses are the majority of causec. Strep pneumo is a major cause if it is bacterial in etiologyd. Less than 10% of patients are febrile
Questions 2. A 45 yo male presents with
sudden onset of fever, rigors, shortness of breath and rust colored sputem. The most likely cause is:a. H. Flub. Legionellac. Strep pneumod. M. catarrhalis
Questions 3. The most common cause of CAP
in an HIV patient is:a. Strep pneumob. Tuberculosisc. H. Flud. Pneumoncystis carinii
Questions 4. T or F: Klebsiella is the most common
cause of CAP in alcoholics. 5. A 57 yo male presents with nonproductive
cough, fever of 102, dyspnea and diarrhea. His labs show a WBC of 18,000 and Na of 129. The most likely cause is:a. H. Flub. Strep pneumoc. Mycoplasmad. Legionella
Answers 1. C 2. C 3. A 4. False 5. D