Diagnostic studies-pneumonia

(AJRCC 2019;200:e45)

• Sputum Gram stain and Cx:
• Procalcitonin:
• CXR (PA & lateral; see Radiology inserts)
• HIV test (if unknown); MRSA nares swab in HAP/VAP (if ⊖ 96% NPV for MRSA PNA)
• Consider in severe disease (otherwise not recommended):
  • Legionella urinary Ag (detects L. pneumophila L1 serotype, 60–70% of clinical disease)S. pneumoniae urinary Ag (Se 70%, Sp >90%)
  • Blood cultures (before antibiotics!): ⊕ in ~10% of inPts, depending on pathogen
• if clinical suspicion for mTB pneumonia
• Viral testing (DFA or PCR) on nasopharyngeal swab or sputum
• Bronchoscopy indication:
• Reasons for failure to improve on initial treatment of pneumonia :