Evaluation of Multiple Real-Time PCR Tests on Nasal Samples in a Large MRSA Surveillance Program

Abstract

Our results suggest that the performance of the three commercial assays is similar. When assessing economic cost benefit of methicillin-resistant Staphylococcus aureus screening, the two measures with the most impact are the cost of the test and the specificity of the assay results.

Methicillin-Resistant Staphylococcus aureus Control in the 21st Century: Laboratory Involvement Affecting Disease Impact and Economic Benefit from Large Population Studies

“…The other factors important for the decision are test cost and performance specificity. The test cost directly impacts the expense of the assay to the laboratory and the specificity of the assay impacts the cost of the program to the health care organization (7,33). For example, a test with high cost and high specificity may actually be less expensive overall than one with low cost and low specificity since low specificity leads to unnecessary patient isolation, which can add as much as $30,000 of unnecessary isolation cost for every 10,000 tests done for each 1% loss of test specificity (33).…”

“…The test cost directly impacts the expense of the assay to the laboratory and the specificity of the assay impacts the cost of the program to the health care organization (7,33). For example, a test with high cost and high specificity may actually be less expensive overall than one with low cost and low specificity since low specificity leads to unnecessary patient isolation, which can add as much as $30,000 of unnecessary isolation cost for every 10,000 tests done for each 1% loss of test specificity (33). More discussion of the potential economic and patient safety impacts of test specificity is provided by Brukner and colleagues, who point out that some commercial assays have unacceptably low specificity (which can be improved) that can lead to adverse outcomes, especially when colonization prevalence is low (34).…”

Nonimpact of Decolonization as an Adjunctive Measure to Contact Precautions for the Control of Methicillin-Resistant Staphylococcus aureus Transmission in Acute Care

“…Paired nasal swabs were collected on all inpatients at admission and discharge from April 2010 through August 2012. One swab was used for real-time PCR, following the manufacturer's recommendation (19). The second swab (swab 2) was used for culture, and the result of this was used to determine the rate of MRSA transmission.…”

Molecular Diagnostics in Pulmonary Infections

“…An important component of the diagnostic armamentarium in pneumonia is a family of assays aimed at detecting bacterial antigens in bodily fluids (e.g., serum and urine). This approach is Commercially available [13,15,19,27] Mass spectrometry for proteomic profiling (continued) already in widespread practice given its relatively low cost, high specificity, rapid processing times, and ready accessibility to samples. The principal disadvantage derives from the indirect detection of pathogen through an antigen rather than isolation of the organism, which is necessary for assessing antibiotic susceptibility [11,12].…”