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Published on: September 25, 2019
Does pH Influence the Bacterial Profile of Chronic Lesions? An Analysis of Venous Ulcer Samples
Fernanda Rabello Sergio1, Nathália Caldas Santos, Isabelle Andrade Silveira
1At the Fluminense Federal University, Niterói, Rio de Janeiro, Brazil, Fernanda Rabello Sergio and Nathália Caldas Santos are master's students; Isabelle Andrade Silveira, PhD, RN, is Head Nurse, Antonio Pedro University Hospital; Bruna Maiara Ferreira Barreto Pires, PhD, is Professor, School of Nursing; Gabriel Luis Cavalcanti Valente is an undergraduate student; Lenise Arneiro Teixeira, PhD, is Professor, Felipe Lopes Teixeira, PhD, is Postdoctoral Researcher, and Geraldo Renato de Paula, PhD, is Professor, Faculty of Pharmacy; and Beatriz Guitton Renaud Baptista de Oliveira, PhD, is Professor, School of Nursing. Acknowledgments: This research received financial support from Fundação Carlos Chagas Filho de Amparo à Pesquisa do Estado do Rio de Janeiro (FAPERJ), process number E-26/010.101008/2018. The authors have disclosed no other financial relationships related to this article. Submitted January 18, 2021; accepted in revised form February 24, 2021.
Objective:
To analyze the pH of venous ulcers and their relationship with the quantitative and qualitative bacterial profile of the wounds.
Methods:
Cross-sectional study carried out through data collection and microbiologic analyses of samples obtained from 35 venous ulcers. Investigators performed pH measurement with indicator strips and collected biologic material using swabs. After aerobic and anaerobic cultivation, colony-forming units (CFUs) were counted and used for bacterial identification via mass spectrometry.
Results:
The pH values ranged from 7.9 to 8.7; 8.5 (37.1%) was the most frequent, followed by 8.3 (28.6%). The most common species were Staphylococcus aureus (68.6%), Pseudomonas aeruginosa (62.9%), Proteus mirabilis (45.7%), and Corynebacterium striatum (40.0%). The number of CFUs ranged from 0 to 200,000 in both anaerobiosis and aerobiosis and was predominantly between 1,000 and 10,000 (37.1%) in anaerobiosis and between 10,000 and 100,000 (37.1%) in aerobiosis. No association was found between the different pH values and the variation in CFUs in anaerobiosis (P = .21) and aerobiosis (P = .55) or by bacterial species identified: S aureus (P = .41), P aeruginosa (P = .29), P mirabilis (P = .19), and C striatum (P = .96).
Conclusions:
The pH of venous ulcers did not influence bacterial profile in quantitative or qualitative parameters.
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