-inﬂammation of the bronchi in lower respiratory tract (RT) usually caused by infection.
-One of the most common conditions seen in primary care
-usually follows an upper respiratory tract infection (URI)
-A type of acute bronchitis is acute exacerbation of chronic bronchitis (AECB)
-Infection superimposed on chronic bronchitis
-May lead to respiratory failure
-Most cases of AECB are d/t viral (rhinovirus, inﬂuenza) infection. Bacterial causes are also
common in both smokers (strep puneumoniae, haemophilius inﬂuenzae) and nonsmokers
(mycoplasma pneumoniae, chlamydia pneumoniae).
-Persistent cough is most common symptom
-Production of clear, mucoid sputum, although some patients produce purulent sputum
-fever, headache, malaise, SOBOE
-mildly elevated temp, pulse, and RR with either normal breath sounds or expiratory
-Radiography can differentiate between acute bronchitis and pneumonia, as there is no
radiographic evidence of consolidation or inﬁltrates with bronchitis
-Acute inﬂammation of lung parenchyma caused by microbial agent.
-Discovery of sulpha drugs and penicillin was pivotal in treatment of pneumonia
-Still common and associated with signiﬁcant morbidity and mortality rates
-Pneumococcal Pneumonia = most common bacterial pneum.
-Airway distal to larynx generally sterile d/t ﬁltration, warming and humidifaction, epiglottis
closure over trachea, cough reﬂex, mucociliary escalator mechanism, secretion of
immunoglobulin A, alveolar macrophages
-most likely when defence mechanisms become incompetent or are overwhelmed
-Decreased consciousness leading to depressed cough and epiglottal reﬂexes, allowing
aspiration of oropharyngeal contents into lungs
-tracheal intubation interferes w normal cough and mucociliary escalation mechanism. Also
bypasses upper airways, thus bypassing ﬁltration, humidiﬁcation
-Leukemia, alcoholism, DM, associated with gram-negative bacilli in oropharynx.
Acquisition of Organisms
1. Aspiration from nasopharynx or oropharynx
2. Inhalation of microbes present in air
3. Hematogenous spread from primary infection elsewhere (e.g., Staph aureus)
Types of pneumonia
-Community acquired (CAP) - LRI of lung parenchyma with onset in community or during ﬁrst
2 days post admission.
-Highest incidence in winter
-Smoking!, COPD, recent use of abx, risk of aspiration
-Commonly caused by s pneumoniae and atypical organisms (e.g., legionella, mycoplasma,