The continuous need of outcome data of continuous beta-lactam infusion (or not?)

When I received this invitation for a PRO-CON, I accepted within 1 minute. Only later to realize that it was on “Optimised dosing according to PK/PD principles in patients – does it improve the efficacy of antibiotics?” Luckily I was given the CON, but I was in a poor position upfront: In a twitter poll 93% of voters were PRO (bias not excluded) and my opponent was Jason Roberts. So, this was my line of reasoning: Continue reading


Using qualitative methods to understand determinants of antibiotic prescribing

A couple of new studies provide insight into determinants of antibiotic prescribing using qualitative methodology. A systematic review in the Journal of Hospital Infection highlights the tension between the immediate need of the sick patient (“give ‘em broad spectrum antibiotics and keep ‘em on them for as long as I can get away with” [my caricature]) and the societal needs related to AMR (“we need to balance the individual needs of the patient with the bigger picture of AMR” [again, my caricature]). Also, a clever study by Esmita Charani and colleagues from Imperial College London provides new insight into antibiotic prescribing practice by “going native” and joining ward rounds – effectively becoming a fly on the wall to understand poor antibiotic prescribing practice. The study identified a contrast between antibiotic prescribing in Medicine, where decisions were generally multidisciplinary and policy-informed, and Surgery, where decisions were often ‘defensive’, resulting in prolonged and inappropriate antibiotic use.

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What urine can tell you

Urine should not be seen as a useless excretion product. Doping experts know, as do clinical microbiologists. In two recently published studies zillions of urine cultures were drained from computer systems and linked to primary care data, yielding very interesting findings. One study from Israel quantified the effects of direct and indirect fluoroquinolone use on antibiotic resistance in E. coli, see also our comments to that study. The second comes from the UK, the country that has an ambition to reduce Gram-negative bacterial bloodstream infection rates by 50%, because of increasing BSI rates. This study may provide both the reason for the problem and the direction to meet that ambition. Continue reading

An endless one-sided confidence in Pip-tazo?

This weeks’ publication of the highly controversial results of the MERINO trial in JAMA caused quite a stir on social media. The paper has been viewed >50,000 times and the unexpected outcome has been challenged by many. But what was the conclusion in JAMA? “Among patients with E. coli or K. pneumoniae bloodstream infection (BSI) and ceftriaxone resistance, definitive treatment with piperacillin-tazobactam compared with meropenem did not result in a non-inferior 30-day mortality.” Not and  in the same sentence, a doubled denial, is confusing. More important, as formulated, the study was inconclusive, which nobody seems to accept. We dived into the depths of the reporting and then tried to explain it. Continue reading

A POET with a sledgehammer

Imagine, the look on the face of that ambitious PhD student, each day screening six hospitals for patients with S. aureus endocarditis, opening the NEJM and seeing that the Danes randomized 400 patients with Infective endocarditis (IE). And then his supervisor rubbing in that these 400 all underwent two extra transoesphageal echocardiograms for study purposes, that there were zero losses to follow-up and telling him how many samples of blood were collected to analyze antibiotic concentrations. Luckily, he was scheduled for our Journal club, which allowed him to apply the “trias scientifica”. Continue reading

Gaming with non-inferiority in antibiotic stewardship

An early switch from IV to oral treatment is one of the pillars of antibiotic stewardship. Oral antibiotics are mostly cheaper, hospital stay shortens and thus also the risk of healthcare-associated infections. One problem: before we change our current practice, we must demonstrate that the new strategy is safe. The best evidence comes from a non-inferiority trial. Yet, that usually implies enrolment of many patients. The solution to that problem: put on your poker face when drafting your sample size calculation and hope for the best. Our Danish colleagues show how.  Continue reading

Procalcitonin-guided antibiotics for respiratory tract infections (part 2)

Two weeks ago I posted a blog about an impeccable NEJM study on the effects of procalcitonin (PCT) on antibiotic use in patients with lower respiratory tract infection. I stated that this RCT was one of the first diagnostic studies in this disease area targeting the correct patients and ended by an invitation to identify the fatal flaw. Last week one of the PhD students (Valentijn Schweitzer, absent when the paper was discussed in our journal club) told me that searching a fatal flaw was not needed; as the RCT was unnecessary in the first place. Here is why. Continue reading