Background: Point-of-care testing for infection might help podiatric physicians optimize management of diabetic foot ulcers (DFUs). Glycologic’s proprietary GLYWD product has been developed to detect changes in a patient’s immunologic/inflammatory response related to wound infection. We evaluated how bacterial presence in DFUs relates to GLYWD test outcome.
Methods: This was a single-organization, prospective, controlled cohort study of clinical opinion versus GLYWD test result for DFU infection status and the appraisal of bacterial presence in the wounds and semiquantitative microbiology swab at weeks 0, 3, 6, 12, and 18. Spearman correlation, backward elimination linear regression, and principal components analysis were applied to determine which variables, including degree of bacterial load, are associated with a positive clinical opinion or GLYWD result for DFU infection.
Results: Forty-eight patients were enrolled, and 142 complete wound appraisals were conducted; a consensus outcome between clinical opinion and GLYWD result was achieved in most (n = 122, 86%). Clinical opinion significantly correlated with a higher bacterial load (Spearman rho = 0.38; P < .01), whereas GLYWD did not (rho = –0.010; P = .91). This observation was corroborated with logistic regression analysis, in which a previous observation of both clinical opinion and GLYWD associating with wound purulence and erythema was also confirmed.
Conclusions: Podiatric physicians are guided by hallmark signs of DFU infection, such as erythema and purulence; furthermore, we found that clinical opinion of infection correlates with increased bacterial load. GLYWD test results match clinical opinion in most cases, although the results obtained with this point-of-care method suggest that the degree of bacterial presence might not necessarily mean a higher chance of inducing an immunologic/inflammatory host response to said bacteria.