Pneumonia, Community Acquired

Respiratory System


Clinicals - History

Fact Explanation
{"ops":[{"insert":"Introduction"},{"insert":"\n"}]}
{"ops":[{"insert":"Community-acquired pneumonia (CAP) is an infection of the pulmonary parenchyma, in an immune-competent individual, that has been acquired outside of hospital. CAP is common, with an inpatient mortality rate as high as 14%."}]}
{"ops":[{"insert":"Constitutional symptoms"},{"insert":"\n"}]}
{"ops":[{"insert":"Non-specific symptoms of CAP include fever, malaise and general weakness. These reflect the systemic response to infection.\n\nPatients with atypical CAP can present with prominent non-respiratory symptoms such as referred upper abdominal pain, diarrhea, headache, myalgia, arthralgia and delirium."}]}
{"ops":[{"insert":"Productive cough"},{"insert":"\n"}]}
{"ops":[{"insert":"The cough in pneumonia may be non-productive at the start. However, a productive cough eventually results. The latter is due to the inflammation caused by the infection giving rise to increased mucus and sputum production."}]}
{"ops":[{"insert":"Dyspnea"},{"insert":"\n"}]}
{"ops":[{"insert":"Patients with CAP can present with breathlessness or dyspnea shortly after the prodromal phase of the disease. This is the result of the infection interfering with normal alveolar function."}]}
{"ops":[{"insert":"Pleuritic chest pain"},{"insert":"\n"}]}
{"ops":[{"insert":"Pleuritic chest pain is described as intense sharp, stabbing, or burning pain in the chest, which is exacerbated by breathing, coughing, sneezing, or laughing. This is due to inflammation of the parietal pleura."}]}
{"ops":[{"insert":"Symptoms in the elderly"},{"insert":"\n"}]}
{"ops":[{"insert":"CAP in the elderly may be absent of any respiratory symptoms. Altered mental status, sudden decline in functional capacity and worsening of co-existing diseases may be the only findings. This is due to the lower local and systemic inflammatory response in older people."}]}
{"ops":[{"insert":"Risk factors"},{"insert":"\n"}]}
{"ops":[{"insert":"The history should explore CAP risk factors including:\n\n- Age \u003E65 years\n- Alcohol abuse\n- Coexisting chronic obstructive pulmonary disease (COPD)\n- History of cigarette smoking\n- Influenza and\/or pertussis co-infection\n- Structural anomalies of the lung"}]}
{"ops":[{"insert":"History of exposure"},{"insert":"\n"}]}
{"ops":[{"insert":"A history of exposure should be sought from patients with symptoms suggestive of CAP. This should include the travel history, occupational exposure, and contact with sick people, animals and birds. This may help narrow down the differential diagnosis or likely causative organism."}]}
{"ops":[{"insert":"Atypical CAP"},{"insert":"\n"}]}
{"ops":[{"insert":"Causative organisms of atypical CAP include Mycoplasma pneumoniae, Chlamydophila pneumoniae, Legionella pneumophila and respiratory viruses. As opposed to typical causes of CAP such as Streptococcus pneumoniae, these agents tend to affect younger adults and present with atypical symptoms e.g., headache, muscle pain, weakness and dry cough."}]}
{"ops":[{"insert":"Causative organisms"},{"insert":"\n"}]}
{"ops":[{"insert":"Globally, Streptococcus pneumoniae is the most common cause of CAP; and it is often encountered in co-infection with influenza.\n\nOther common organisms causing CAP include Haemophilus influenzae, Pseudomonas aeruginosa and Moraxella catarrhalis. Less common pathogens causing CAP include Enterobacteriaceae, Staphylococcus aureus and fungi, such as Pneumocystis jirovecii, aspergillus or coccidioides.\n\nNote that not all patients will have an identifiable pathogen."}]}
{"ops":[{"insert":"Introduction"},{"insert":"\n"}]}
{"ops":[{"insert":"Community-acquired pneumonia (CAP) is an infection of the pulmonary parenchyma, in an immune-competent individual, that has been acquired outside of hospital. CAP is common, with an inpatient mortality rate as high as 14%."}]}
{"ops":[{"insert":"Constitutional symptoms"},{"insert":"\n"}]}
{"ops":[{"insert":"Non-specific symptoms of CAP include fever, malaise and general weakness. These reflect the systemic response to infection.\n\nPatients with atypical CAP can present with prominent non-respiratory symptoms such as referred upper abdominal pain, diarrhea, headache, myalgia, arthralgia and delirium."}]}
{"ops":[{"insert":"Productive cough"},{"insert":"\n"}]}
{"ops":[{"insert":"The cough in pneumonia may be non-productive at the start. However, a productive cough eventually results. The latter is due to the inflammation caused by the infection giving rise to increased mucus and sputum production."}]}
{"ops":[{"insert":"Dyspnea"},{"insert":"\n"}]}
{"ops":[{"insert":"Patients with CAP can present with breathlessness or dyspnea shortly after the prodromal phase of the disease. This is the result of the infection interfering with normal alveolar function."}]}
{"ops":[{"insert":"Pleuritic chest pain"},{"insert":"\n"}]}
{"ops":[{"insert":"Pleuritic chest pain is described as intense sharp, stabbing, or burning pain in the chest, which is exacerbated by breathing, coughing, sneezing, or laughing. This is due to inflammation of the parietal pleura."}]}
{"ops":[{"insert":"Symptoms in the elderly"},{"insert":"\n"}]}
{"ops":[{"insert":"CAP in the elderly may be absent of any respiratory symptoms. Altered mental status, sudden decline in functional capacity and worsening of co-existing diseases may be the only findings. This is due to the lower local and systemic inflammatory response in older people."}]}
{"ops":[{"insert":"Risk factors"},{"insert":"\n"}]}
{"ops":[{"insert":"The history should explore CAP risk factors including:\n\n- Age \u003E65 years\n- Alcohol abuse\n- Coexisting chronic obstructive pulmonary disease (COPD)\n- History of cigarette smoking\n- Influenza and\/or pertussis co-infection\n- Structural anomalies of the lung"}]}
{"ops":[{"insert":"History of exposure"},{"insert":"\n"}]}
{"ops":[{"insert":"A history of exposure should be sought from patients with symptoms suggestive of CAP. This should include the travel history, occupational exposure, and contact with sick people, animals and birds. This may help narrow down the differential diagnosis or likely causative organism."}]}
{"ops":[{"insert":"Atypical CAP"},{"insert":"\n"}]}
{"ops":[{"insert":"Causative organisms of atypical CAP include Mycoplasma pneumoniae, Chlamydophila pneumoniae, Legionella pneumophila and respiratory viruses. As opposed to typical causes of CAP such as Streptococcus pneumoniae, these agents tend to affect younger adults and present with atypical symptoms e.g., headache, muscle pain, weakness and dry cough."}]}
{"ops":[{"insert":"Causative organisms"},{"insert":"\n"}]}
{"ops":[{"insert":"Globally, Streptococcus pneumoniae is the most common cause of CAP; and it is often encountered in co-infection with influenza.\n\nOther common organisms causing CAP include Haemophilus influenzae, Pseudomonas aeruginosa and Moraxella catarrhalis. Less common pathogens causing CAP include Enterobacteriaceae, Staphylococcus aureus and fungi, such as Pneumocystis jirovecii, aspergillus or coccidioides.\n\nNote that not all patients will have an identifiable pathogen."}]}

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