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Essentials of Diagnosis
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Productive cough, fever, rigors, dyspnea, early pleuritic chest pain
Consolidating lobar pneumonia on chest radiograph
Lancet-shaped gram-positive diplococci on Gram stain of sputum
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General Considerations
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High fever, productive cough, occasional hemoptysis, and pleuritic chest pain
Rigors may occur initially but are uncommon later in the course
Bronchial breath sounds are an early sign
Differentiating pneumococcal from other bacterial pneumonias is not possible clinically or radiographically because of significant overlap in presentations
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Differential Diagnosis
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Pneumonia due to other causes, eg, Haemophilus influenzae, influenza
Aspiration pneumonia or lung abscess
Pulmonary embolism
Myocardial infarction
Acute exacerbation of chronic bronchitis
Acute bronchitis
Hypersensitivity pneumonitis
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A rapid urinary antigen test for Streptococcus pneumoniae, with sensitivity of 70–80% and specificity > 95%, can assist with early diagnosis
A good-quality sputum sample (less than 10 epithelial cells and more than 25 polymorphonuclear leukocytes per high-power field) shows gram-positive diplococci in 80–90% of cases
Blood cultures are positive in up to 25% of selected cases and much more commonly so in HIV-positive patients
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Chest radiograph shows findings of consolidation, often with a lobar distribution, infiltrates, pleural effusion
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Aqueous penicillin G (susceptible strains), 2 million units every 4 hours intravenously
Ceftriaxone, 1 g every 24 hours intravenously
For a highly penicillin-resistant strain, vancomycin, 1 g every 12 hours intravenously
Alternatively, a fluoroquinolone (eg, levofloxacin, 750 mg) can be used
Total duration of therapy is not well defined but 5–7 days is appropriate for patients who have an uncomplicated infection and demonstrate a good clinical response
Corticosteroid use remains controversial in community-acquired pneumonia and should not be administered routinely
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Therapeutic Procedures
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