No abstract

Use of the CDSS was associated with more appropriate AM use. To achieve greater improvements, strategies are needed to improve provider diagnoses of syndromes that are infectious or possibly infectious.

Impaired development of local Ab responses may predispose HIV-1-infected patients to an increased rate, severity, and duration of mucosal infections. We characterized the repertoire of Ig-producing cells in the intestinal effector compartment (the lamina propria) of HIV-1-infected (n = 29) and seronegative control (n = 27) subjects. The density of Ig-producing cells per area was similar in both groups. However, the proportions of IgA-producing cells were lower in both the duodenum and colon from HIV-1-infected patients compared with those of control subjects (p < 0.05), with compensatory increases in IgG-producing cells in the colon and IgM-producing cells in the duodenum. Similarly, among Abs in the lumen the proportions of IgA were also decreased and the proportions of IgG were increased among HIV-1-infected patients. On a molecular level, VH gene repertoire analyses by RT-PCR revealed comparable proportions of the VH3 family among duodenal IgA transcripts (50–53%) from both groups. VH3 expression was decreased only for IgM among patients with advanced HIV-1 disease (n = 6) compared with that of control subjects (n = 8) (48 ± 8 vs 62 ± 13%; p < 0.01). Moreover, the frequencies of individual IgM and IgA VH3 genes were comparable in each group, including rates of putative HIV-1 gp120-binding VH3 genes (V3-23, V3-30, V3-30/3-30.5). We conclude that, despite a decrement in local IgA producing cells, the density and molecular VH repertoire of mucosal plasma cells are relatively intact among patients with HIV-1 infection. These data suggest that HIV-1-infected patients use functional regulatory mechanisms to provide sufficient VH diversity and effective induction and differentiation of mucosal B cells.

A hospital cafeteria-associated outbreak of gastroenteritis due to Salmonella enterica serotype Infantis was retrospectively evaluated using modified repetitive element PCR (rep-PCR) fingerprinting with the ERIC2 and BOXA1R primers and computer-assisted gel analysis and dendrogram construction. Rep-PCR yielded objective between-cycler, same-strain similarity values of from 92% (composite fingerprints) to 96% (ERIC2 fingerprints). The 70 Salmonella isolates (which included 19 serotype Infantis isolates from the hospital outbreak, 10 other serotype Infantis isolates, and 41 isolates representing 14 other serotypes) were resolved well to the serotype level with each of the three fingerprint types (ERIC2, BOXA1R, and composite). Rep-PCR typing uncovered several historical serotyping errors and provided presumptive serotype assignments for other isolates with incomplete or undetermined serotypes. Analysis of replicate fingerprints for each isolate, as generated on two different thermal cyclers, indicated that most of the seeming subserotype discrimination noted in single-cycler dendrograms actually represented assay variability, since it was not reproducible in combined-cycler dendrograms. Rep-PCR typing, which would have been able to identify the presence of the hospital-associated serotype Infantis outbreak after the second outbreak isolate, could be used as a simple surrogate for serotyping by clinical microbiology laboratories that are equipped for diagnostic PCR.

Background. We have reported that diagnostic errors factor into 89% of inappropriate inpatient antimicrobial (AM) courses. Here we describe in detail the diagnostic errors that led to inappropriate courses.Methods. We studied AM courses given to 500 randomly selected VA hospital inpatients between 2007 and 2008. We recorded information about the syndrome or disease that led to AM use (index condition), the initial provider diagnosis of the index condition ( provider diagnosis), and AM drug(s), dose, route, and duration. Each case summary was assigned randomly to 2 of 4 blinded reviewers. Based on data available to providers in real time, reviewers classified the provider diagnosis as correct, uncertain, not correct, or a sign or symptom of a potential infection rather than a syndrome or disease (sign or symptom) and the index AM course as appropriate or not, considering drug selection, route, dose, and duration.Results. Overall, provider diagnoses were correct in 292/500 (58%) of cases, but accuracy varied by diagnosis. For the 6 most common diagnostic groups (376 [75%] of all cases), accuracy ranged from 90% for bacteremia or sepsis to 27% for cystitis, pyelonephritis, or urosepsis (P < .001). Provider AM courses were considered appropriate in 191/500 (38%) of cases overall, but appropriateness varied in relation to diagnostic accuracy. When provider diagnoses were correct, 181/292 (62%) of courses were appropriate compared with only 10/208 (5%) when diagnoses were incorrect, uncertain, or signs or symptoms (P < .001). Considering the 111 cases in which provider diagnoses were correct and AM courses were inappropriate, reasons included wrong AM drug(s) (81, 73%), wrong duration (43, 39%), wrong dose (5, 5%), another type of drug error (1, 1%), and AM therapy not indicated (11, 4%). In contrast, of the 198 cases in which provider diagnoses were incorrect or uncertain or were signs or symptoms and AM courses were inappropriate, AM therapy was not indicated in 171 (86%) cases. Other reasons included wrong AM drugs (31, 16%), incorrect duration (13, 7%), wrong dose (2, 1%), and another type of drug error (1, 0.5%).Conclusion. Efforts to improve AM courses should include strategies to help providers make accurate diagnoses of syndromes that might be due to infection.