A comparative analysis of tissue swabs versus deep tissue samples in infected foot ulcers in the diabetic Maltese population.

Abstract

AIM The aim of this study is to identify the most accurate microbiological test in detecting micro-organisms in infected diabetic foot ulcers in people living with Type 2 diabetes in Malta. The two test compared in this study were the superficial swab and the deep tissue sample. RESEARCH DESIGN AND METHOD An exploratory same-subject design study was conducted at the Diabetes and Endocrine Centre, Mater Dei Hospital Malta from July 2008 to December 2008. Twenty patients living with Type 2 diabetes were randomly recruited from the out-patient clinic. The sample comprised twenty patients presenting for the first time with an infected foot ulcer. A diabetes data collection sheet was used to gather information as regard to their diabetic treatment, foot complications and history about foot ulceration. Participants were assessed for peripheral neuropathy using the 10 gram monofilament, five point's testing procedure. Peripheral vascular disease was assessed using foot pulse palpations. Infected foot ulcers were graded according to the Wagner's classification. Two swabs, a superficial sample and a deep tissue sample, were collected from each participant. Further data on medical history regarding patients was obtained from the annual medical report held at the Diabetes and Endocrine Centre, Mater Dei Hospital. RESULTS The study found a significant difference (p = 0.028) between the two different samples. The deep tissue sample was found to be more accurate in identifying micro-organisms then the superficial swabs. Furthermore this study identified peripheral vascular disease and peripheral neuropathy as the most common diabetes complications amongst the study population. It also identified that most ulcers were already grade 3 on the Wagner's classification when presenting for the first time at the Diabetes Foot Clinic. CONCLUSION A significant difference was found in the accuracy of identifying micro-organisms present in infected foot ulcers among people living with Type 2 diabetes between two microbiological tests. Results demonstrated that the deep tissue sample is more accurate in identifying micro-organisms than the superficial swab which is currently being used inside the Diabetes Foot Clinic. Furthermore these findings demonstrated that patients are being referred to the diabetes foot clinic presenting already with serious diabetes mellitus complications, such as peripheral vascular disease, peripheral neuropathy and grade 3 ulcerations.