Initial Antibiotics in Sepsis - Uncited

Hospitalized adults pending identification of causative organism

Suspected Clinical Diagnosis	Likely Etiologic Diagnosis	Drugs of Choice
Meningitis, bacterial, community-acquired6	Pneumococcus1, meningococcus	Cefotaxime2, 2–3 g IV every 6 hours; or ceftriaxone, 2 g IV every 12 hours plus vancomycin, 10 mg/kg IV every 8 hours
Meningitis, bacterial, age > 50, community-acquired6	Pneumococcus, meningococcus, Listeria monocytogenes3, gram-negative bacilli	Ampicillin, 2 g IV every 4 hours, plus Cefotaxime or ceftriaxone and vancomycin
Meningitis, postoperative (or posttraumatic)6	S aureus, gram-negative bacilli (pneumococcus, in posttraumatic)	Vancomycin, 10 mg/kg IV every 8 hours, plus ceftazidime, 3 g IV every 8 hours
Brain abscess	Mixed anaerobes, pneumococci, streptococci	Penicillin G, 4 million units IV every 4 hours, plus metronidazole, 500 mg orally every 8 hours; or Cefotaxime or ceftriaxone plus metronidazole, 500 mg orally every 8 hours
Pneumonia, acute, community-acquired, severe	Pneumococci, M pneumoniae, 'Legionella', C pneumoniae	Doxycycline, 100 mg IV or orally every 12 hours (or azithromycin), plus Cefotaxime, 2 g IV every 8 hours (or ceftriaxone, 1 g IV every 24 hours); or a fluoroquinolone5 alone
Pneumonia, postoperative or nosocomial	S aureus, mixed anaerobes, gram-negative bacilli	Cefapime, 2 g IV every 8 hours; or , 2 g IV every 8 hours; or piperacillin-tazobactam, 45 g IV every 6 hours; or imipenem, 500 mg IV every 6 hours; or meropenem, 1 g IV every 8 hours plus tobramycin, 5 mg/kg IV every 24 hours; or ciprofloxacin, 400 mg IV every 12 hours; or levofloxacin, 500 mg IV every 24 hours plus vancomycin, 15 mg/kg IV every 12 hours
Endocarditis, acute (including injection drug user)	S aureus, E faecalis, gram-negative aerobic bacteria, viridans streptococci	vancomycin, 15 mg/kg IV every 12 hours, plus gentamicin, 1 mg/kg every 8 hours
Septic thrombophlebitis (eg, IV tubing, IV shunts)	S aureus, gram-negative aerobic bacteria	Vancomycin, 15 mg/kg IV every 12 hours plus ciprofloxacin, 400 mg IV every 12 hours; or levofloxacin, 500 mg IV every 24 hours; or ceftriaxone, 1 g IV every 24 hours
Osteomyelitis	S aureus	Nafcillin, 2 g IV every 4 hours; or cefazolin, 2 g IV every 8 hours
Septic arthritis	S aureus, N gonorrhoeae	Ceftriaxone , 1–2 g IV every 24 hours
Pyelonephritis with flank pain and fever (recurrent urinary tract infection)	E coli, Klebsiella, Enterobacter, Pseudomonas	Ceftriaxone, 1g IV every 24 hours; or ciprofloxacin, 400 mg IV every 12 hours (500 mg orally); or levofloxacin, 500 mg once daily (IV/PO)
Fever in neutropenic patient receiving cancer chemotherapy	S aureus, Pseudomonas, Klebsiella, E coli	Ceftazidime, 2 g IV every 8 hours; or cefepime, 2 g IV every 8 hours
Intra-abdominal sepsis (eg, postoperative, peritonitis, cholecystitis)	Gram-negative bacteria, Bacteroides, anaerobic bacteria, streptococci, clostridia	Piperacillin-tazobactam or ticarcillin-clavulanate, 3.1 g IV every 6 hours; or ertapenem, 1 g every 24 hours; or moxifloxacin, 400 mg IV every 24 hours

¹Some strains may be resistant to penicillin. Vancomycin can be used with or without rifampin.

²Cefotaxime, ceftriaxone, ceftazidime, or ceftizoxime can be used. Most studies on meningitis have been with cefotaxime or ceftriaxone (see text).

³TMP-SMZ can be used to treat Listeria monocytogenes in patients allergic to penicillin in a dosage of 15–20 mg/kg of TMP in three or four divided doses.

⁴Depending on local drug susceptibility pattern, use tobramycin, 5 mg/kg/d, or amikacin, 15 mg/kg/d, in place of gentamicin.

⁵Gatifloxacin, levofloxacin, moxifloxacin

⁶Remember to give steroids concomitatntly or 15 minutes prior to antibiotics for acute bacterial meningitis

See Also

• Initial Antibiotics in Sepsis (Main)