Assessment of risk factors for multi-drug resistant organisms to guide empiric antibiotic selection in long term care: a dilemma.

Multidrug-resistant organisms (MDRO) are a significant problem in many long-term care facilities (LTCFs), as well as hospitals. It is important that practitioners identify residents at risk for infection with MDROs. The risk factor assessment should be done before selecting empiric antibiotic therapy. It is well documented that during critical illness failure to “get it right the first time” with antibiotic therapy leads to excess mortality. The data for this conclusion come from studies of hospitalized patients that included identifying the etiologic organism in culture and documenting resistance by sensitivity testing. In clinical practice it is difficult to get cultures in LTCFs, especially in residents with pneumonia, and there will inevitably be a delay in obtaining the results, so empiric therapy must be given, and should consider risk factors for MDRO. If this is done, it may lead to more accurate antibiotic choices, and may prevent some patients with a mild-moderately severe infection from becoming severely ill as a consequence of inappropriate empiric therapy. The American Thoracic Society/ Infectious Disease Society of America (ATS/IDSA) Clinical Practice Guideline for Health-Care Associated Pneumonia focused on patients ill enough to require hospital admission. It is unclear how this Guideline should be applied to residents with pneumonia who remain in the nursing home. The Guideline recommended performing a risk factor assessment for MDRO, combined with a low threshold for using empiric antibiotics directed at MDRO, along with efforts to culture the causative pathogen to allow “de-escalation” of antibiotic therapy. This approach can give the best of all worlds: appropriate and effective therapy, while limiting the duration of broad-spectrum therapy, a responsible strategy