What's New in Antibiograms? Updating CLSI M39 Guidance with Current Trends.

A vast amount of antimicrobial susceptibility test (AST) data is generated from routine testing in diagnostic laboratories for the primary purpose of guiding clinicians in antimicrobial therapy decisions for their patients. However, there is additional value for these data when they are compiled at the local, regional, national, and global levels. Cumulative AST data can be used to prepare antibiograms at the individual health care facility level. These reports can be used to gain insight into appropriate empirical therapy options prior to the availability of AST results on an individual patient's isolate. Different types of cumulative AST data reports can also be compiled at the regional, national, and global levels to estimate susceptibility rates in geographic regions, document trends in evolving microbial populations, and recognize the appearance and spread of emerging antimicrobial resistance threats. The first CLSI M39 Guideline for Analysis and Presentation of Cumulative AST Data was published in 2000. Since that time, there have been changes to AST and reporting recommendations as well as the introduction of advanced informatics technologies to analyze and present data. The 5th edition of M39 has taken into consideration these changes to assist those who analyze, present, and utilize routine antibiograms and other types of cumulative AST data reports as well as those who design information systems for the capturing and analyzing of AST data. Furthermore, antimicrobial stewardship programs (ASPs) have expanded considerably, and uses of the antibiogram by ASPs have been addressed. This minireview will remind users of the basic recommendations for analysis and presentation of antibiograms and provide new suggestions to enhance these reports.

Enhancing the empiric antibiotic selection by introducing an antibiogram toolkit in a tertiary care hospital in Southern India - A prospective study.

WHAT IS KNOWN AND OBJECTIVE: Antibiograms gives an overview of the cumulative susceptibility of formal antibiotics to bacterial isolates, which reflects the portion of each bacterium susceptible to a given antibiotic formulation by using antimicrobial susceptibility testing. The objective of this study is to gather and analyse data from drug utilization evaluation (DUE) studies and antimicrobial susceptibility tests in order to create an antibiogram toolkit that will help clinicians to select appropriate antimicrobial agents for initial empirical antibiotic therapy at point of care settings and avoid irrational use of antibiotics. METHODS: A prospective interventional study was conducted at tertiary care hospital, biological samples of infectious patients were collected from various wards as per Clinical & Laboratory Standards Institute CLSI M39-A4 guidelines. Antimicrobial susceptibility results were analysed using WHONET software. Antibiotic stewardship committee was formed and involved in monitoring the usage of antibiotics, measuring outcomes, collecting feedback and finding the scope for improving the application of antibiogram toolkit in the hospital. Antibiotic usage tracking method was followed to know the level of adherence to the prescribing guidelines by the health care professionals. RESULTS AND DISCUSSION: A total of 157 samples were obtained from various wards of the hospital. In that, Escherichia coli, Staphylococcus aureus and Klebsiella Pneumoniae were isolated in significant numbers. Antibacterial susceptibility results were collected, an initial antibiogram was developed for 18 antibacterial agents with respect to 3 gram-positive (+) and 1 gram-negative (-) organisms. 90% of prescribers mentioned that the antibiogram was useful, and 76% of them adhered to the guidelines. 26% were not adhered due to the patient-related factors. WHAT IS NEW AND CONCLUSION: In our study, we have used qualitative and quantitative evaluation of drug utilization (DUE) reports to understand the existing prescribing pattern of antibiotics and setting target organisms and antibacterials to develop the hospital antibiogram. Combining DUE studies and antibiogram development was helpful in implementing effective antibiotic policies for the hospital. Further, this study pattern will be continued on a yearly basis and focused on developing cumulative antibiograms to understand the changes in resistance pattern of antimicrobials and utilization of antibiotics in the hospital.

Influence of the Novel Histamine H3 Receptor Antagonist/Inverse Agonist M39 on Gastroprotection and PGE2 Production Induced by (R)-Alpha-Methylhistamine in C57BL/6 Mice.

The role of histamine H3 receptors (H3Rs) in the regulation of gastroprotection and production of prostaglandin E2 (PGE2) as well as somatostatin remains contradictory. Therefore, the effects of the H3R antagonist/inverse agonist M39 on in vivo acidified ethanol-induced gastric ulcers and gastric acid secretion in the C57BL/6 mice were assessed. Results showed that acute systemic administration of H3R agonist (R)-α-methylhistamine (RAMH, 100 mg/kg, i.g.) significantly reduced the severity of ulcer index, increased gastric acid output, and increased mucosal PGE2 production without any alteration of somatostatin concentration in gastric juice. However, only acute systemic administration of the H2R agonist dimaprit (DIM, 10 mg/kg, p.o.) significantly decreased the level of somatostatin measured in gastric juice. Moreover, acute systemic administration of M39 (0.3 mg/kg, i.g.) abrogated the RAMH-induced increase of acid output as well as PGE2 production, but not the DIM (10 mg/kg, i.g.)-stimulated acid secretion, indicating that RAMH as well as M39 modulate the gastroprotective effects through interactions with histamine H3Rs. The present findings indicate that agonistic interaction with H3Rs is profoundly involved in the maintenance of gastric mucosal integrity by modulating PGE2 as well as gastric acid secretion, with no apparent role in the regulation of the inhibitory influence of somatostatin.