Temporal changes in the diversity and composition of the bed microbiota of patients with pressure ulcers

Abstract

　Wound infection is a life-threatening problem in pressure ulcers and still develops despite interventions to reduce bioburden on wounds and periwound skin. We focused on the bed environment as the hotbed for bacteria on the wound because many patients with pressure ulcers are immobile. However, the formation process of the bed microbiota remains unclear. This study aimed to investigate the temporal changes in the diversity and composition of the bed microbiota of one patient each with an infected pressure ulcer, non-infected pressure ulcer, and without a pressure ulcer. Microbiome samples were obtained from three areas, namely the bed sheet area around the buttocks, center of the wound, and periwound skin for 7 consecutive days. The microbiota were determined by 16S ribosomal RNA gene sequencing. Sequences were clustered into operational taxonomic units, and diversity indices were calculated. Regarding the evaluation of temporal changes, the day following the changing of bed sheets was designated as the starting point. The analysis of alpha diversity showed no significant changes in bed environment over time, and this was evident in all patients. In addition, the temporal change in the composition of bed microbiota for the patient with a pressure ulcer was greater than for the patient without a pressure ulcer. This finding suggests that the bed environment is a source of wound microbiota, and the presence of a pressure ulcer is likely to affect the bed environment. Interventions in the bed environment may be effective to prevent wound infection.