Evaluation of Glycologic Point-of-Care Infection Test Kit for Diabetic Foot Ulcers in Relation to Bacterial Presence: A Prospective Cohort Study.

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.

A Pragmatic, Single-Center, Prospective, Randomized Controlled Trial of Adjunct Hemoglobin-Mediated Granulox Topical Oxygen Therapy Twice Weekly for Foot Ulcers.

BACKGROUND: Achieving timely healing of foot ulcers can help avoid complications such as infection and amputation; topical oxygen therapy has shown promise in achieving this. We evaluated the clinical effectiveness of Granulox, a hemoglobin spray device designed to deliver oxygen to the surface of wounds, for the healing of foot ulcers. METHODS: We conducted a single-center, prospective, randomized controlled trial comparing standard of care (once-weekly podiatric medical clinic visits) versus standard care plus adjunct Granulox therapy twice weekly in adults with foot ulcers. After a 2-week screening phase, patients in whom the index wound had healed by less than 50% were randomized 1:1. Outcome measures were collated during the trial phase at 6 and 12 weeks. RESULTS: Of 79 patients enrolled, 38 were randomized. After 12 weeks, the median percentage wound size reduction compared with the size of the ulcer at the start of the trial phase was 100% for the control arm and 48% for the Granulox arm (P = .21, Mann-Whitney U test). In the former, eight of 14 foot ulcers had healed; in the latter, four of 15 (P = .14, Fisher exact test). In the control arm, two amputations and one withdrawal occurred, whereas in the Granulox arm, one unrelated death and five withdrawals were recorded. CONCLUSIONS: We could not replicate the favorable healing associated with use of Granulox as published by others. Differences in wound chronicity and frequency of Granulox application might have influenced differences in study results. Granulox might perform best when used as an adjunct for treatment of chronic wounds at least 8 weeks old.

Point-of-care testing for bacterial infection in diabetic foot ulcers: a prospective cohort study.

OBJECTIVE: To appraise the performance of a new point-of-care wound infection detection kit in diabetic foot ulcers (DFUs), using clinician opinion as the primary comparator. The proprietary swab-based chromatic Glycologic (Glycologic Ltd., UK) detection kit used in this study is designed to detect host response to pathogenic levels of bacteria in wounds. METHOD: In high-risk podiatry clinics, patients with DFUs were recruited and infection detection kit test results compared with initial clinician opinion. Chi-squared tests, principal component analysis (PCA) and multiple regression analysis were performed to determine which variables were possibly associated with infection. The variables considered were patients' wound parameters, wider vascular comorbidity and demographics. RESULTS: A total of 136 patients, providing 383 wound swabs, were included in the study. Total agreement in terms of DFU wound assessment for infection-between podiatrists' clinical opinion and Glycologic kit test result-was observed in 79% of cases (301/383). For 56 of the 349 negative infection detection kit test results (16%), podiatrists identified a 'possible' or 'definite' infection. Conversely, in 14 of the 307 cases (4.6%) where podiatrists deemed the wound 'not infected', the infection detection kit test showed a colour change. Regression analysis and PCA showed that clinical signs of wound infection, namely erythema, purulence and odour, were all significantly associated with both a positive clinical opinion and infection detection kit test result. However, in the case of the infection detection kit, a patient's number of lesions and vascular comorbidities were also significantly correlated with a positive test result. CONCLUSION: A host response to critical pathological levels of bioburden in a wound-as detected with the infection detection kit-may partly be determined by an individual patient's (vascular) health and therefore be person-specific. Further research is indicated to determine the relationship between an infection detection kit test result and the microbiological status of the wound.