Efficacy of Antipseudomonal Agents

List of Antipseudomonal Agents

Antipseudomonal Agents	SENSITIVITY**
	Pseudomonas sp	P. aeruginosa
Ticarcillin-clavulanate	Not available	Not available
Piperacillin-tazobactam	83.3%	66.7%
Piperacillin	91.2%	89%
Cephalosporins
Ceftazidime	95.7%	93.2%
Cefoperazone	60.7%	79.9%
Cefoperazone/Sulbactam	88.9%	90.9%
Cefepime	100%	0%
Monobactam
Aztreonam	Not available	Not available
Fluoroquinolones
Levofloxacin
Ciprofloxacin	80%	100%
Carbapenems
Meropenem	80%	84.2%
Doripenem	Not available	Not available
Imipenem/Cilastatin	100%	85.7%
Other Antibiotics
Colistin (Polymyxin E)	Not available	Not available
Polymyxin B	Not available	Not available
Aminoglycosides
Amikacin	93.4%	100%
Gentamicin	Sensitivity to Gentamicin 10mcg: 94.5%	Sensitivity to Gentamicin 10mcg : 98.4%
Tobramycin	Not Available	Not Available

**Sensitivity results from isolates in Hospital Keningau, Sabah in 2013

• Cefoperazone: A study done in a Malaysian general hospital showed that increased sensitivity (in vitro) observed if sulbactam is added
• Aztreonam is not recommended to be used as monotherapy
• Levofloxacin has no advantage over ciprofloxacin in term of coverage. Levofloxacin primarily indicated for Respiratory Tract Infection. But 750mg/day can be used in polymicrobial infection susceptible to streptococci and P. aeruginosa.
• Other fluoroquinolones agents are not recommended (eg: Moxifloxacin)
• MIC:
• Doripenem< Meropenem < Imipenem
• Imipenem less recommended due to higher risk of resistance developing during treatment.
• All carbapenems associated with resistance emergence thus reserved in cases resistant to all other agents or polymicrobial infections

GENERAL PRINCIPLES OF TREATMENT & RECOMMENDATION

• Empiric or Directed therapy affected by the Antibiotic Resistance (Intrinsic and acquired) Combination therapy is indicated in certain high risk patients and in severe infections. 
• Antimicrobial therapy should be prompt, as delayed therapy correlates with increased mortality. 
• All infected catheters should be removed, and abscesses or obstructions should be drained or removed, whenever possible
• Choice of antibiotics should be referred from guidelines (http://askdis.blogspot.my/2016/01/antibiotic-choices-for-p-aeruginosa.html) and also the sensitivity result of the pathogen.

REFERENCES

1. www.uptodate.com
2.  https://www.researchgate.net/publication/14272308_In_vitro_activity_of_cefoperazone-sulbactam_combination_against_cefoperazone_resistant_clinical_isolates_in_a_Malaysian_general_hospital
3. National Antibiotic Guidelines 2014
4. British Medical Journal
5. Antibiotic Guidelines 2015-2016 (John Hopkins)