The use of antibiotics can be based on either the clinical course of a patient without the benefit of well-defined microbiologic data (empiric therapy), or targeted at specific identified pathogens once sensitivity reports are available (directed therapy). The following statement(s) is/are true concerning these therapies.
A. The issue of toxic side effects of antibiotics is only important in dealing with emperic therapy B. Single agent therapy is generally inferior to specific multi-drug therapy (aminoglycoside plus an antianaerobic agent) for the treatment of secondary bacterial peritonitis due to appendicitis, diverticulitis, penetrating gastrointestinal injury, or anastomotic leak C. With the empiric use of antibiotics, a diligent search for the septic source should be undertaken and continued until identified D. In clinical situations in which polymicrobial infection is identified, specifically-directed treatment for the predominant organism is satisfactory
With the empiric use of antibiotics, a diligent search for the septic source should be undertaken and continued until identified-the use of empiric therapy without the benefit of well-defined microbiologic data is appropriate when there is sufficient clinical evidence to support the diagnosis such that it would be imprudent to withhold antimicrobial therapy. in this setting, however, a diligent search for the septic focus source should be undertaken and continued (cultures, radiographic procedures, etc.), and initial limits should be placed in the course of empiric therapy with continued reevaluation based on the clinical course of the patient. the choice of antibiotic agents should be based on the clinical situation and known activity patterns within the given institution. single broad-spectrum agents, although suffering slightly from a lack of individual pathogen specificity, are useful in this setting in that they provide a broad coverage against several groups of pathogens and may avoid some of the toxic effects with specific combined modality regimens. similarly, for directed therapy, single-agent therapy has been demonstrated to be equivalent to combined therapy and should be chosen in an attempt to select agents with appropriate sensitivities which retain suitable clinical efficacy but exhibit minimal toxicity. after review of cultural reports, many patients have demonstrated polymicrobial infection. because experimental clinical evidence supports the concept of aerobic-anaerobic synergy, therapy should be directed against all potential components of the infection if the body site is such that these microorganisms may be present.