Usefulness of cerebrospinal fluid bacterial antigen tests

Abstract

To the Editor:We found the recent article1Maxson S Lewno MJ Schultze GE Clinical usefulness of cerebrospinal fluid bacterial antigen studies.J PEDIATR. 1994; 125: 235-238Abstract Full Text Full Text PDF PubMed Scopus (52) Google Scholar attempting to quantify the clinical utility of the cerebrospinal fluid (CSF) Directigen test (Becton Dickinson Microbiology Systems, Cockeysville, Md.) very interesting. This study addresses issues of cost containment that are vital to providing quality care in a managed care environment. If a diagnostic study or therapeutic intervention is without utility, it should be abandoned. We applaud the authors for having the intellectual courage to examine the usefulness of CSF bacterial studies in that light.Of the 901 reviewed circumstances in which a CSF Directigen test was obtained, 29 antigen test results were positive and 872 results were negative. The authors describe in detail the negligible impact that the positive test result had on the management of the 29 patients with positive results, but are curiously silent about the 872 patients with negative results, except to say that results for 6 patients were deemed falsely negative. Is it possible that the real benefit of the Directigen test is in the true-negative results? How many of these patients would have been hospitalized and given intravenously administered antibiotics (with all of the costs involved) had it not been for the negative Directigen test result? Preventing only a few needless admissions each year could more than offset the cost savings of not performing the test.Given that the purpose of the study was to try to find ways to cut costs without decreasing the quality of care rendered, have the authors considered eliminating the routine ordering of determinations of CSF protein and glucose levels? On the basis of our understanding of their protocol, the results of these determinations apparently never affected the clinical decisions made for patients in whom a diagnosis of meningitis was suspected. At a cost of $54 per test, not obtaining these studies in the 901 subjects would have saved nearly $49,000 during the study period. Perhaps the utility of those tests should be the focus of a future clinical review.In this era of changes in health care delivery, all health care professionals are obligated to seek opportunities to cut costs. Provided our efforts serve to eliminate the ”dead wood“ and preserve the ”good wood,“ we can be assured that we are making progress; however, it is incumbent on us to consider the value of a negative test result when we make those determinations. This article serves an admirable purpose in focusing our attention toward the goal of practicing quality, cost-conscious medicine, but until all of the potential cost benefits of a negative test result are included in the equation, the author's conclusion that the Directigen test not be used is premature.9/35/61127 To the Editor:We found the recent article1Maxson S Lewno MJ Schultze GE Clinical usefulness of cerebrospinal fluid bacterial antigen studies.J PEDIATR. 1994; 125: 235-238Abstract Full Text Full Text PDF PubMed Scopus (52) Google Scholar attempting to quantify the clinical utility of the cerebrospinal fluid (CSF) Directigen test (Becton Dickinson Microbiology Systems, Cockeysville, Md.) very interesting. This study addresses issues of cost containment that are vital to providing quality care in a managed care environment. If a diagnostic study or therapeutic intervention is without utility, it should be abandoned. We applaud the authors for having the intellectual courage to examine the usefulness of CSF bacterial studies in that light.Of the 901 reviewed circumstances in which a CSF Directigen test was obtained, 29 antigen test results were positive and 872 results were negative. The authors describe in detail the negligible impact that the positive test result had on the management of the 29 patients with positive results, but are curiously silent about the 872 patients with negative results, except to say that results for 6 patients were deemed falsely negative. Is it possible that the real benefit of the Directigen test is in the true-negative results? How many of these patients would have been hospitalized and given intravenously administered antibiotics (with all of the costs involved) had it not been for the negative Directigen test result? Preventing only a few needless admissions each year could more than offset the cost savings of not performing the test.Given that the purpose of the study was to try to find ways to cut costs without decreasing the quality of care rendered, have the authors considered eliminating the routine ordering of determinations of CSF protein and glucose levels? On the basis of our understanding of their protocol, the results of these determinations apparently never affected the clinical decisions made for patients in whom a diagnosis of meningitis was suspected. At a cost of $54 per test, not obtaining these studies in the 901 subjects would have saved nearly $49,000 during the study period. Perhaps the utility of those tests should be the focus of a future clinical review.In this era of changes in health care delivery, all health care professionals are obligated to seek opportunities to cut costs. Provided our efforts serve to eliminate the ”dead wood“ and preserve the ”good wood,“ we can be assured that we are making progress; however, it is incumbent on us to consider the value of a negative test result when we make those determinations. This article serves an admirable purpose in focusing our attention toward the goal of practicing quality, cost-conscious medicine, but until all of the potential cost benefits of a negative test result are included in the equation, the author's conclusion that the Directigen test not be used is premature. We found the recent article1Maxson S Lewno MJ Schultze GE Clinical usefulness of cerebrospinal fluid bacterial antigen studies.J PEDIATR. 1994; 125: 235-238Abstract Full Text Full Text PDF PubMed Scopus (52) Google Scholar attempting to quantify the clinical utility of the cerebrospinal fluid (CSF) Directigen test (Becton Dickinson Microbiology Systems, Cockeysville, Md.) very interesting. This study addresses issues of cost containment that are vital to providing quality care in a managed care environment. If a diagnostic study or therapeutic intervention is without utility, it should be abandoned. We applaud the authors for having the intellectual courage to examine the usefulness of CSF bacterial studies in that light. Of the 901 reviewed circumstances in which a CSF Directigen test was obtained, 29 antigen test results were positive and 872 results were negative. The authors describe in detail the negligible impact that the positive test result had on the management of the 29 patients with positive results, but are curiously silent about the 872 patients with negative results, except to say that results for 6 patients were deemed falsely negative. Is it possible that the real benefit of the Directigen test is in the true-negative results? How many of these patients would have been hospitalized and given intravenously administered antibiotics (with all of the costs involved) had it not been for the negative Directigen test result? Preventing only a few needless admissions each year could more than offset the cost savings of not performing the test. Given that the purpose of the study was to try to find ways to cut costs without decreasing the quality of care rendered, have the authors considered eliminating the routine ordering of determinations of CSF protein and glucose levels? On the basis of our understanding of their protocol, the results of these determinations apparently never affected the clinical decisions made for patients in whom a diagnosis of meningitis was suspected. At a cost of $54 per test, not obtaining these studies in the 901 subjects would have saved nearly $49,000 during the study period. Perhaps the utility of those tests should be the focus of a future clinical review. In this era of changes in health care delivery, all health care professionals are obligated to seek opportunities to cut costs. Provided our efforts serve to eliminate the ”dead wood“ and preserve the ”good wood,“ we can be assured that we are making progress; however, it is incumbent on us to consider the value of a negative test result when we make those determinations. This article serves an admirable purpose in focusing our attention toward the goal of practicing quality, cost-conscious medicine, but until all of the potential cost benefits of a negative test result are included in the equation, the author's conclusion that the Directigen test not be used is premature. 9/35/61127