In that study, nine factors were associated with the risk of bacteremia: no influenza vaccination in the last year, no pneumococcal vaccination in the last five years, blood urea nitrogen (BUN) level ≥30 mg/dL, sodium level <130 mmol/L, lymphocyte count <800/μL, C-reactive protein level ≥200 mg/L, respiratory failure, pleural effusion, and no previous antibiotic use before admission. Here, CRP is linked to Pleural effusion.