For decades we have taught the same thing. If you suspect diabetic foot osteomyelitis (DFO) and you are going to bone biopsy, hold the antibiotics for a week or two beforehand. The IWGDF and IDSA guidelines have largely echoed this advice. The reasoning is intuitive enough: drugs in the bloodstream contaminate the petri dish, so let the bugs come up clean.
A new systematic review and meta-analysis in Wound Repair and Regeneration from our friends and colleagues Lavery LA, Tarricone AN, Madsen AWE, Thirugnanasambandam N, Gee A, Wukich DK, and Peters EJG now asks whether that intuition actually holds up under the weight of the data.
The short answer: it might not.
What they did
The team performed a PRISMA-compliant meta-analysis pooling all comparative studies they could find where patients suspected of DFO underwent bone biopsy, with culture yields stratified by whether or not they had received antibiotics beforehand. PubMed, EMBASE, and the Cochrane Library were searched. Pooled odds ratios were calculated with a random-effects Mantel–Haenszel model, with heterogeneity assessed via the I² statistic and Cochran’s Q. Four studies met inclusion criteria.
What they found
The cumulative odds ratio for a positive culture in patients with antibiotic exposure versus those naïve to antibiotics was 0.78 (95% CI 0.31–1.98, p = 0.60). In plain language: no statistically significant difference. Pre-biopsy antibiotics did not meaningfully reduce the chance of growing a pathogen from bone. Heterogeneity was moderate (I² = 50%), and the authors are appropriately measured about how far one ought to extrapolate from four studies.
Why it matters
This is a small literature interrogating a big dogma. If the answer holds up across larger and prospective datasets, the implications are real and immediate.
- We may not need to delay treatment in a patient with a brewing pedal infection simply to “wash out” before biopsy.
- Conversely, antibiotic stewardship still matters—but the rationale shifts from “you will ruin the culture” to “we should not be exposing tissue to drugs we do not yet need.”
- For the patient on the table, this could mean less suffering and a shorter time-to-source-control.
This is exactly the kind of clinical question we love at SALSA and at DFCon: the practices we inherit are often more inherited than tested. Four studies is a starting line, not a finish line. But Larry, Edgar, Dane and their team have done the field a service by putting this question squarely on the table where it belongs.
You can find the paper here: https://doi.org/10.1111/wrr.70171 (PMID 42141702).
Read it. Argue with it. And most of all, use it to ask the patient in front of you the right next question.
#DiabeticFoot #DFO #Osteomyelitis #BoneBiopsy #AntibioticStewardship #MetaAnalysis #WoundCare #DFCon #SALSA #LimbPreservation
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