Minor microbial alterations after faecal diversion do not affect the healing process of anus-near pressure injuries in patients with spinal cord injury - results of a matched case-control study.

ABSTRACT

STUDY DESIGN: Retrospective matched case-control study including patients with spinal cord injury who presented with an anus-near pressure injury. Two groups were formed based on the presence of a diverting stoma. OBJECTIVES: To evaluate the primary microbial colonisation and secondary infection of anus-near pressure injuries depending on the presence of a pre-existing diverting stoma and to investigate the effect on the wound healing. SETTING: University hospital with a spinal cord injury unit. METHODS: A total of 120 patients who had undergone surgery of an anus-near decubitus stage 3 or 4 were included in a matched-pair cohort study. Matching was realised according to age, gender, body mass index and general condition. RESULTS: The most common species in both groups was Staphylococcus spp.(45.0%). The only significantly different primary colonisation affected Escherichia coli, that was found in the stoma patients less often (18.3 and 43.3%, p < 0.01). A secondary microbial colonisation occurred in 15.8% and was equally distributed, except for Enterococcus spp. that was present in the stoma group only (6.7%, p < 0.05). The time to complete cure took longer in the stoma group (78.5 versus 57.0 days, p < 0.05) and was associated with a larger ulcer size (25 versus 16 cm2, p < 0.01). After correction for the ulcers' size, there was no association to outcome parameters such as overall success, healing time or adverse events. CONCLUSIONS: The presence of a diverting stoma alters the microbial flora of an anus-near decubitus slightly without impact on the healing process.