Antibiotics for Bone and Joint Infections (Adults)

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  1. Osteomyelitis
    *investigations: blood cultures (x2), bone cultures (CT-guided or open biopsy for culture in vertebral osteomyelitis), CBC and differential, serum creatinine, ESR/CRP (low sensitivity for diagnosis but if initially elevated then either can be used to monitor response), plain x-ray +/- MRI OR bone scan +/- WBC scan
    **MRI superior to x-ray and bone scan for early diagnosis, and superior to CT scan for vertebral osteomyelitis and identification of epidural abscess
    ***bone scan may be falsely positive if recent trauma/aspiration of joint/superficial infection (WBC or gallium scan may improve specificity)
    ****clindamycin achieve excellent bone penetration and is a good agent for osteomyelitis if organism susceptible. However due to high resistance rates, not recommended empirically
    • Vertebral (spinal osteomyelitis, spondylodiscitis, septic discitis, disc space infection):
    • *caused by: hematogenous seeding, direct inoculation at time of surgery, contiguous spread from adjacent soft tissue
    • **if staphylococcal hardware infection, add rifampin. Ensure TB has been ruled out before rifampin initiation.
    • S. aureus/MRSA:
    • 1. cloxacillin 2g IV Q4H x6/52

    • B-lactam allergy:
    • 1. vancomycin 25-30mg/kg IV once then 15mg/kg IV Q8-12H x6/52
    • *desired trough= 15-20mg/L

    • Alternative: 
    • 1. linezolid 600mg IV/PO Q12H x6/52
    • 2. SMX/TMP 15-20mg TMP/kg/d IV/PO divided Q6-8H x6/52

    • If MRSA suspected:
    • *consider MRSA if: preceding trauma, multifocal lesions, disease in adjacent muscle
    • **if no debridement, add rifampin 600mg PO daily or 300-450mg PO BID x minimum 8/52
    • 1. vancomycin 25-30mg/kg IV once then 15mg/kg IV Q8-12H x minimum 8/52
    • *desired trough= 15-20mg/L
    • 2. linezolid 600mg PO Q12H x minimum 8/52
    • 3. SMX/TMP 15-20mg TMP/kg/d IV/PO divided Q6-8H x minimum 8/52

    • Hematogenous long bones= S.aureus/MRSA, Streptococcus spp./Enterobacteriaceae/M. tuberculosis/Dimorphic fungi (rare):
    • Treatment:
    • 1. cloxacillin 2g IV Q4H x4=6/52
    • 2. cefazolin 2g IV Q8H x4=6/52

    • B-lactam allergy:
    • 1. vancomycin 15mg/kg IV Q8-12H x4-6/52
    • *desired trough= 15-20mg/L
    • 2. clindamycin 600mg IV Q8H x4-6/52
    • 3. clindamycin 450mg PO QID x4-6/52
    • *clindamycin can be used if: bacteremia cleared, no intravascular infection, AND documented susceptibility

    • If MRSA suspected:
    • 1. vancomycin 15mg/kg Q8-12H x minimum 8/52 +/- rifampin 600mg PO daily OR rifampin 300-450mg PO BID
    • *if no debridement, consider adding rifampin and continue therapy for minimum 12/52

    • Intravenous drug use= S. aureus/MRSA, P. aeruginosa, Salmonella spp./Serratia spp./Candida spp./Anaerobes (occasionally), M. tuberculosis (rare):
    • 1.vancomycin 15mg/kg Q8-12H x6/52 + ciprofloxacin 750mg PO BID x6/52 OR tobramycin 7mg/kg IV Q24H x6/52
    • *if MSSA= cloxacillin or cefazolin. If MRSA= vancomycin alone
    • **reassess need for FQ or aminoglycoside therapy as soon as C&S results available

    • Contiguous vascular insufficiency, diabetic foot= polymicrobial
    • *tetanus Px recommended
    • **bone biopsy recommended
    • ***anaerobic coverage recommended
    • ****if known/suspected P. auruginosa, use ciproflixacin or ceftazidime instead of ceftriaxone
    • Mild to moderate:
    • 1. clindamycin 450mg PO QID x≥6/52 + ciprofloxacin 750mg PO BID x≥6/52
    • 2. cefazolin 2g IV Q8H x≥6/52 + metronidazole 500mg PO BID x≥6/52
    • *cefazolin and metronidazole combination doesn't cover P. aeruginosa

    • If MRSA suspected:
    • 1. ADD SMX/TMP 2 DS PO BID x≥6/52 to regimens above

    • Out patient and failure of oral therapy or known/suspected ESBL/Amp C-producing organisms:
    • 1. ertapenem 1g IV daily x≥6/52
    • *ertapenem has no P. aeruginosa coverage

    • Moderate to severe and MRSA suspected:
    • 1. vancomycin 15mg/kg IV Q8-12H x≥6/52 + ceftriaxone 1-2g IV daily x≥6/52 + metronidazole 500mg IV/PO Q12H x≥6/52
    • *vancomycin, ceftriaxone and metronidazole combination doesn't have P. aeruginosa coverage
    • **desired vancomycin trough= 15-20mg/L

    • Severe/limb threatening:
    • 1. PIPTAZO 3.375mg IV Q6H x≥6/52 OR imipenem 500mg IV Q6H x≥6/52 + vancomycin 15mg/kg IV Q8-12H x≥6/52
    • *if P. auruginosa detected, use PIPTAZO 4.5g IV Q6H if renal function allows
    • **if known/suspected ESBP/Amp C-producing organism, use imipenem

    • Contiguous post-nail puncture of foot= P. aeruginosa, S. aureus/Bacillus spp./Anaerobes (occasionally):
    • Prophylaxis:
    • *local debridement/tetanus Px recommended
    • **osteomyelitis develop in 1-2% of plantar puncture wounds. Consider Px if within 24h of nail puncture
    • 1. ciprofloxacin 750mg PO BID x5/7

    • Treatment:
    • *tetanus Px recommended 
    • 1. PIPTAZO 4.5mg IV Q6H x minimum 6/52 (IV + PO)

    • Oral therapy:
    • 1. ciprofloxacin 750mg PO BID to complete minimum of 2/52

    • Post-operative sternotomy/mediastinitis= S. aureus/MRSA, S. epidermidis, Enterobacteriaceae/Corynebacterium spp./Candida spp.
    • 1. vancomycin 15mg/kg IV Q8-12H x6-8/52 +/- ciprofloxacin 500-750mg PO BID x6-8/52 OR ciprofloxacin 400mg IV Q12H x6-8/52 OR gentamicin 7mg/kg IV Q24H x6-8/52
    • *reassess need for FQ or aminoglycoside Tx as soon as C&S results available
  2. Prosthetic joint infections
    *diagnosis: presence of at least one of the following: sinus tract communicating with prosthesis, isolation of same organism from ≥2 cultures of joint aspirates or periprosthetic tissue, gross purulence in joint space, acute inflammation on histological exam (>5PMNs/hpf)
    **ANTX therapy should be discontinued ≥2/52 prior to surgery and perioperative ANTX should be deferred until after intraoperative cultures have been taken
    ***early (<3/12) after implant= S. aureus, Coagulase negative staphylococci (CoNS), Enterobacteriaceae
    ****delayed(3-24/12)= CoNS, Propionibacterium spp., Anaerobes, S. aureus
    *****late/hematogeneous (>2y)= Streptococcus spp., Enterococcus spp., Abiotrophia spp., Granulicatella spp., S. aureus, CoNS, Enterobacteriaceae, P. aeruginosa
    ******polymicrobial (20%), culture-negative (7-11%), fungi (1%)
    • Treatment:
    • *recommended duration= debridement and retention or one-stage exchange (2-4/52 IV followed by PO Tx for total of 3/12 for hip and 3-6/12 for knee prostheses), two-stage exchange (4-8/12 of ANTX Tx + ≥2/52 ANTX-free interval before re-implantation. Post-op: continue ANTX Tx until intraoperative cultures come back negative, as long as ANTX was stopped ≥2/52 prior to surgery, or for 6-12/52 if positive intraoperative cultures)
    • 1. vancomycin 15mg/kg IV Q8-12H + rifampin 450mg PO BID +/- ciprofloxacin 750mg PO BID
    • *desired vancomycin trough= 15-20mg/L
    • **ciprofloxacin may be considered emperically for Gram negative coverage, especially if early (<3/12)

    • Alternative PO therapy:
    • 1. ciprofloxacin 750mg PO BID OR levofloxacin 750mg PO daily OR minocycline 100mg PO BID OR doxycycline 100mg PO BID OR SMX/TMP 1 DS PO TID + rifampin 450mg PO BID

    • If surgery is CI:
    • *longterm/life-long suppressive Tx
    • **rifampin is not necessary since goal is to control clinical manifestations of infection rather than eradication
    • 1. agent according to C&S result 
    • 2. SMX/TMP 1 DS PO TID
    • 3. minocycline 100mg PO BID
    • 4. doxycycline 100mg PO BID

    • Shoulder arthroplasty, rotator cuff surgery= P. acnes, S. aureus, polymicrobial (occasionally):
    • *consider adding rifampin 450mg PO BID if hardware cannot be removed
    • **may need additional PO Tx on an individualized basis
    • 1. vancomycin 15mg/kg IV Q8-12H x4-6/52

    • Documented P. acnes infection:
    • 1. penicillin 4MU IV Q6H x4-6/52
    • 2. ceftriaxone 2g IV daily x4-6/52
  3. Septic arthritis
    *investigations: blood cultures (positive in 60%) x2, synovial fluid for cell count/C&S/crustal analysis, CBC and differential/serum creatinine, ESR/CRP (low sensitivity but can be used to monitor response, plain x-ray +/- MRI OR bone scan +/- WBC or gallium scan
    • Native joints +/- non-penetrating trauma= S. aureus, Streptococcus spp., Candida spp./P. aeruginosa/Enterobacteriaceae (rare):
    • 1. cloxacillin 2g IV Q4H x2-4/52 OR cefazolin 2g IV Q8H x2-4/52 +/- ciprofloxacin 750mg PO BID x2-4/52 OR gentamicin 7mg/kg IV Q24H x2-4/52
    • *consider adding ciprofloxacin or gentamicin if IVDU/immunocompromised/elderly as increased risk of Gram negative infection

    • B-lactam allergy/MRSA:
    • 1. vancomycin 15mg/kg IV Q8-12H x2-4/52 OR clindamycin 600mg IV Q8H x2-4/52 OR clindamycin 450mg PO QID x2-4/52 +/- ciprofloxacin 750mg PO BID x2-4/52 OR gentamicin 7mg/kg IV Q24H x2-4/52
    • *consider MRSA if: preceding trauma, multifocal lesion, disease in adjacent muscle
    • *desired vancomycin trough= 15-20mg/L

    • Gonococcal
    • Tenosynovitis/dermatitis/polyarthralgia syndrome= Neisseria gonorrhoeae:
    • *all patients: empiric Tx for concomitant Chlamydia trachomatis infections (azithromycin 1g PO x single dose OR doxycycline 100mg PO BID x7/7), test for HIV/syphilis/hep B, culture urine (males)/vagina or cervix (females)/rectum/throat/blood/joint fluid (and treat accordingly), test and treat all recent (60 days) sexual contacts
    • 1. ceftriaxone 2g IV daily x3-7/7 
    • *continue IV for 24 hours after improvement of symptoms

    • Oral therapy:
    • 1. cefixime 400mg PO BID x to complete 7/7
    • 2. cirprofloxacin 500mg PO BID x to complete 7/7
    • *high FQ resistance= only use of susceptibility documented

    • Purulent arthritis:
    • 1. joint drainage PLUS ceftriaxone 2g IV daily x7-14/7

    • Rheumatoid arthritis-associated infection= S. aureus, Streptococcus spp., Enterobacteriaceae
    • *if on TNF inhibitors, consider unusual bacterial, mycobacterial, or fungal pathogens
    • 1. cefazolin 2g IV Q8H x4/52 +/- ciprofloxacin 750mg PO BID x4/52 OR gentamicin 7mg/kg Q24H x4/52

    • B-lactam allergy:
    • 1. clindamycin 600mg IV Q8H x4/52 OR clindamycin 450mg PO QID x4/52 + ciprofloxacin 500mg PO BID x4/52

    • Intravenous drug use= S. aureus/MRSA, P. aeruginosa, Candida spp. (occasionally):
    • 1. vancomycin 15mg/kg IV Q8-12H x3-4/52 + ciprofloxacin 750mg PO BID x3-4/52 OR tobramycin 7mg/kg Q24H x3-4/52
    • *desired vancomycin trough= 15-20mg/L
    • **if MSSA, use cloxacillin or cefazolin as superior to vancomycin
Card Set:
Antibiotics for Bone and Joint Infections (Adults)
2015-01-12 05:54:27

recommended empiric therapy for bone and joint infections
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