Platelet Rich Plasma (PRP) is a blood product having a platelet concentration above baseline. In vitro studies have reported that PRP may significantly inhibit the growth of undesirable pathogens in diabetic foot ulcers (Bielecki et al. 2007, Moojern et al. 2008). This study aimed to determine the inherent antibacterial properties of autologous PRP from 40 study participants. The participants consisted of 3 groups. Healthy diabetics - no complications of diabetes and a HbA1c <8% (n=13) and their healthy age gender matches (n=13) and a discreet group of 14 participants who had a non-healing diabetic foot ulcer with no antibiotic therapy in the preceding 21 days. Ethical approval was obtained from ORECNI (10/NIRO2/30). A sample of 55ml of whole venous blood was drawn from each participant and prepared as per the manufacturer’s instructions to produce PRP. The antibacterial efficacy of PRP was established using the well diffusion assay. Five wells were aseptically created in each nutrient agar plate seeded with lawns of S. aureus (NCTC 8329), Ps. aeruginosa (NCTC 10780), Methicillin resistant S. aureus (MRSA) (NCTC 8323), MRSA - clinical isolate, S. pyogenes (β Haemolytic Streptococcus) (NCTC10876), Proteus vulgaris (NCTC10031) and E. coli (NCTC09001). These bacteria are of significance in diabetic foot wounds (Lipsky and Berendt 2000, Vardakas et al., 2008). PRP from the study participants was aseptically transferred into 4 of the wells; the 5th (control) well contained Ringers solution. The plates were incubated at 37 °C for 24 hours, and the resultant zones of inhibition were used to provide a semi-quantitative estimation of antibacterial activity. Results Zones of inhibition (ZOI) were observed on the lawns of S.aureus, S. pyogenes, and Proteus vulgaris, of all participants. ZOI were also observed on the lawns of MRSA (both types) in the age gender matched group and participants with an active diabetic foot wound. Enhanced growth of Ps. aeruginosa was observed in the healthy participants (n=11), as previously found by Bielecki et al. (2007), but was also observed in participants with diabetes and participants with diabetes (n=10) and an active diabetic foot wound (n=13). Discussion These findings may be clinically significant, as they demonstrate that PRP has a wider than previously recognised range of antimicrobial activity against infecting / contaminating bacteria. Zones of inhibition were not identified for all the participants on the plates with lawns of these organisms. The significance of these effects requires further investigation in the clinical environment as the in vitro findings may not mimic what happens in vivo. Clinically, the lack of antimicrobial properties against Ps. aeruginosa is important as Ps.aeruginosa causes 9.3% to 31% of diabetic foot infections (Viswanathan, 2007); is known to form biofilms, which delay wound healing (Swarna et al., 2012) and has been linked to the migration of keratinocytes. These observations are significant in wound healing (Loryman and Mansbridge 2007). The findings of this work, indicates that it would be advisable to sample a wound prior to the application of autologous PRP to ensure there was no evidence of the presence of Ps. aeruginosa.
|Title of host publication||College of Podiatrists|
|Publication status||Published (in print/issue) - Nov 2018|
|Event||College of Podiatrists annual conference - Bournemouth conference Centre, Bournemouth, United Kingdom|
Duration: 22 Nov 2018 → 24 Nov 2018
|Conference||College of Podiatrists annual conference|
|Period||22/11/18 → 24/11/18|
- PRP, Antimicrobial