<|endoftext|>450 inhibitor). Poor choice for bacteremia/endocarditis due to static nature.
5. Tigecycline (IV)
Mechanism: Glycylcycline class - structurally related to Tetracyclines (bacteriostatic). Only IV.
Spectrum: Broad coverage - Gram positive (including MRSA and VRE), Gram negatives, anaerobes, and atypicals. Notable holes in coverage include Pseudomonas, Proteus, and Providencia.
Used for: complicated intraabdominal infections, skin/soft tissue infections, and sometimes for pneumonia. Beware overall increased risk of death when used for severe infections (2010 metanalysis) – FDA black box warning!
when used for severe infections (2010 metanalysis) – FDA black box warning! High rate of failure for HAP/VAP , use with caution
, use with caution Achieves low serum concentrations (distributes widely into tissues) – poor choice for bacteremia (also note its static mechanism)
(also note its static mechanism) Sometimes effective against MDR gram negative pathogens including some ESBL and carbapenemase-producing strains – if dealing with such a bug, should ask micro to test susceptibility to tigecycline.
– if dealing with such a bug, should ask micro to test susceptibility to tigecycline. Main side effects = GI (nausea/vomiting/diarrhea) and elevated LFTs 6. Ceftaroline (5th Gen Cephalosporin) – see Beta-lactam section above. Covers MRSA, VISA, VRSA, Strep, Enterococcus faecalis/VRE (but not as good vs E.faecium). Similar gram negative coverage as Ceftriaxone.
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VI. ��SUPER GRAM NEGATIVE ANTIBIOTICS�� THAT COVER PSEUDOMONAS
Pseudomonas aeruginosa is a non-fermenting Gram-negative bacillus that inhabits a variety of environments (soil, water) and causes nosocomial infections (HAP/VAP, catheter-related infections, UTIs, post-surgical) and commonly affects immunocompromised patients (common cause of neutropenic fever, ecthyma gangrenosum), cystic fibrosis, and burn patients. It is feared due both for its inherent resistance to most antibiotics as well as its propensity to develop resistance. For serious infections due to suspected Pseudomonas, generally recommended to ��empirically double cover�� with two antibiotics from different classes until susceptibilities identified, then narrow appropriately to one drug. However , the utility of ��continued double-coverage�� (after susceptibilities identified) is a long-standing point of controversy – some experts recommend this for serious infections including bacteremia in neutropenic patients, endocarditis, meningitis, and possibly pneumonia.
However the utility of ��continued double-coverage�� (after susceptibilities identified) is a long-standing point of controversy Double coverage involves a beta-lactam plus either Fluoroquinolone or Aminoglycoside. Use Aztreonam if PCN-allergic. Avoid double beta-lactam therapy.
Only Ciprofloxacin and Levofloxacin come in PO form, all other are IV only. 1. Zosyn(Piperacillin/Tazobactam) and Timentin (Ticarcillin/Clavulanate) – note high rates of resistance to Ticarcillin.
2. Carbapenems – Meropenem, Imipenem , Doripenem. Remember: Ertapenem has no activity.
3. Ceftazidime, Cefepime (4th gen cephalosporin)
4. Aztreonam – high rates of resistance at most institutions, so use only if PCN-allergic, and empirically double-cover.
5. Fluoroquinolones - Ciprofloxacin (~70% coverage) > Levofloxacin (~65%), NOT Moxifloxacin (0%) - usually used as double coverage, not for monotherapy for empiric Pseudomonas treatment.
6. Aminoglycosides – On average, Amikacin > Tobramycin > Gentamicin - generally do not use as monotherapy for serious Pseudomonas infections except for UTIs (tend to have worse outcomes), only as 2nd agent added to primary beta lactam therapy.
7 . Polymyxins