Introduction
Diabetes mellitus, one of the most common chronic metabolic diseases
worldwide, is characterized by high blood sugar and leads to many
serious complications.1 The complications caused by
long-term high blood glucose include nephropathy, retinopathy and
neurovascular complications.2 One of the most serious
conditions of diabetes-related neurovascular complications is foot
ulcers. It was estimated that approximately 15% of people with type 2
diabetes would be affected by foot ulcers.3 However,
in 2015, the International Diabetes Federation reported that this rate
was approximately 34%.4 Diabetic foot ulcers lead to
amputation at various levels, depending on severity, in approximately
20% of patients. Furthermore, diabetic foot ulcers increase the risk of
death. Patients with diabetic foot ulcers have a 2.5-fold higher risk of
death at 5 years than those without diabetic foot
ulcers.5 Unfortunately, despite significant
improvements in diabetic foot care and treatment, the rate of amputation
due to diabetic foot ulcers is increasing.
One of the classifications of diabetic foot ulcers was developed by
Wagner in the 1970s, in which ulcers were graded between 0-5. In this
classification, only the depth of the ulcer, osteomyelitis and gangrene
are evaluated, but the presence of ischemia is not
considered.6, 7, New classification systems have been
developed after this classification; however, the Wagner classification
is simple and very effective in predicting low extremity
amputation.8, 9 Ischemia in tissues due to the
decreased blood flow in diabetic foot ulcers is not considered in the
Wagner classification, making it difficult to determine the level of
amputation. Therefore, a biomarker to help determine the level of
ischemia in these patients may be more effective in determining the
degree of amputation. Classical blood parameters such as the erythrocyte
sedimentation rate (ESR), C-reactive protein (CRP), procalcitonin and
white blood cells (WBC) are used to determine the severity of infection
in diabetic foot ulcers. However, there is no blood biomarker to
determine the level of ischemia in diabetic foot
ulcer.10
Ischemia-modified albumin (IMA) is a structure formed by the change of
the N-terminal end as a result of ischemic damage of circulating
albumin; due to this modification, the transport of elements such as
cobalt and nickel is impaired.11 In recent years, many
studies have been reported on whether IMA may be a novel predictor in
ischemic injury-related diseases such as stroke, acute mesenteric
ischemia, acute pulmonary embolism and coronary
syndrome.12 In previous studies, IMA levels were
examined for diabetes and diabetes-related complications such as
diabetic nephropathy and diabetic ketoacidosis.13 It
has also been reported that IMA may be an indicator of diabetes-related
complications.14 In the literature review we
conducted, we found only one study that examined IMA levels in diabetic
foot patients, but there is no study examining the relationship of IMA
levels with the Wagner classification in these
patients.15
In this study, we aimed to compare IMA levels in diabetic foot patients
and a healthy control group. In addition, we aimed to determine the
relationship of IMA levels with diabetic foot severity by grouping
diabetic foot patients according to the Wagner classification.