Appropriateness of alert antibiotics measured by repeated prevalence surveys and impact of direct prescriber interaction and feedback.

OBJECTIVES: Hospital point prevalence surveys (PPS) are shown to help identifying determinants for inappropriate antimicrobial therapy (AMT) and create feedback opportunities to optimize AMT. METHODS: PPS were performed at the AZNikolaas hospital, on four wards with high consumption rates of three alert antibiotics (AB) to judge their appropriateness. The impact of a multidisciplinary interaction between a medical microbiologist, a clinical pharmacist and the prescriber on inappropriate AMT, hospital costs and intravenous AMT days, was analyzed. RESULTS: During this survey, 7,39% of hospitalized patients in the selected wards received one or more of three alert antibiotics. Out of 78 prescriptions, 35.90% were judged appropriate, 39.74% inappropriate and 24.36% had insufficient data for judgment. Only the oncology ward was associated with more frequent appropriate use of alert AB. In case of an unknown infection focus or a catheter-related infection, the relative risk of inappropriate use was the highest. Multidisciplinary interaction improved inappropriate AMT in 59% of cases. It resulted in a 2478€ healthcare AMT cost saving and a reduction of 30 intravenous AMT days. CONCLUSIONS: This survey shows high consumption rates and a high rate of inappropriate use of three alert AB in the observed wards. It revealed the lack of a local guideline concerning treatment of neutropenic fever of unknown origin and the need for more diagnostic information in electronical medical records. The survey demonstrated that direct feedback on inappropriate AMT to clinicians can be of added value, cost-saving and reducing length of intravenous AMT days. However, more studies are needed to confirm this.

Distinct transcriptome signatures of Helicobacter suis and Helicobacter heilmannii strains upon adherence to human gastric epithelial cells.

The porcine Helicobacter suis and canine-feline H. heilmannii are gastric Helicobacter species with zoonotic potential. However, little is known about the pathogenesis of human infections with these Helicobacter species. To gain more insight into the interactions of both zoonotic Helicobacter species with human gastric epithelial cells, we investigated bacterial genes that are differentially expressed in a H. suis and H. heilmannii strain after adhesion to the human gastric epithelial cell line MKN7. In vitro Helicobacter-MKN7 binding assays were performed to obtain bacterial RNA for sequencing analysis. H. suis and H. heilmannii bacteria attached to the gastric epithelial cells (i.e. cases) as well as unbound bacteria (i.e. controls) were isolated, after which prokaryotic RNA was purified and sequenced. Differentially expressed genes were identified using the DESeq2 package and SARTools pipeline in R. A list of 134 (83 up-regulated and 51 down-regulated) and 143 (60 up-regulated and 83 down-regulated) differentially expressed genes (padj ≤ 0.01; fold change ≥ 2) were identified for the adherent H. suis and H. heilmannii strains, respectively. According to BLASTp analyses, only 2 genes were commonly up-regulated and 4 genes commonly down-regulated in both pathogens. Differentially expressed genes of the H. suis and H. heilmannii strains belonged to multiple functional classes, indicating that adhesion of both strains to human gastric epithelial cells evokes pleiotropic adaptive responses. Our results suggest that distinct pathways are involved in human gastric colonization of H. suis and H. heilmannii. Further research is needed to elucidate the clinical significance of these findings.