Gram Positive Cocci
An enterococcus was isolated from a urine specimen. Treatment of the patient with ampicillin and gentamicin faileD. What is the most clinically appropriate action?
|A||Consider vancomycin as an alternative drug|
|B||Determine if fluorescent microscopy is available for the diagnosis of actinomycosis|
|C||Do no further clinical workup|
|D||Suggest of the laboratory that low colony counts may reflect infection|
a. These questions demonstrate commonly occurring clinical infectious diseases and microbiologic problems.
b. Enterococci may be resistant to ampicillin and gentamicin. Vancomycin would be the drug of choice. However, laboratory results do not always correlate well with clinical response.
c. The National Committee on Clinical Laboratory Standards recommends testing enterococci only for ampicillin and vancomycin.
d. Some symptomatic patients may have 10 leukocytes per mL of urine but relatively few bacteria. The patient is likely infected and the organisms, particularly if in pure culture, should be further processed.
e. The patient in question 251 probably has actinomycosis. These laboratory data are not uncommon.
f. There is no reason to work up all the contaminating bacteria. A fluorescent microscopy test for A. israelii is available. If positive, the FA provides a rapid diagnosis.
g. In any event, it may be impossible to recover A. israelii from such a specimen. High-dose penicillin has been used to treat actinomycosis.