Diabetic foot overview: Difference between revisions
| Line 23: | Line 23: | ||
==Risk Factors== | ==Risk Factors== | ||
There are numerous [[risk factors]] for [[diabetic foot]] development in a [[diabetes|diabetic]] [[patient]], such as poor [[blood sugar|glycaemic]] control, inappropriate [[foot]] care and [[foot]]wear, [[foot]] [[deformity|deformities]], [[peripheral arterial disease]], [[peripheral neuropathy]], history of previous [[foot]] [[ulcer]] or [[amputation]], [[infection]], high [[body mass index]] and poor socioeconomic status. Other [[Comorbidity|comorbidities]] such as [[hypertension]] and [[Lipoprotein disorders|dyslipidemia]] are also responsible as [[risk factors]] for [[diabetic foot]] [[ulcer|ulceration]]. | |||
==Screening== | ==Screening== | ||
Revision as of 19:35, 14 July 2021
|
Diabetic foot Microchapters |
|
Diagnosis |
|---|
|
Treatment |
|
Case Studies |
|
Diabetic foot overview On the Web |
|
American Roentgen Ray Society Images of Diabetic foot overview |
|
Risk calculators and risk factors for Diabetic foot overview |
Editor-In-Chief: C. Michael Gibson, M.S., M.D. [1] Associate Editor(s)-in-Chief: Vishnu Vardhan Serla M.B.B.S. [2] Anahita Deylamsalehi, M.D.[3] Usama Talib, BSc, MD [4]
Overview
Type 2 diabetes and its complications are now considered as a growing health threat. It is the leading cause of blindness, end stage renal disease, coronary heart disease and foot ulceration which leads to amputations. In general, the incidence of nontraumatic lower extremity amputations has been reported to be at least 15 times greater in those with diabetes than with any other medical illness. Among patients with diabetes, the lifetime risk of having foot ulcer is 15%. Diabetic foot ulcers dramatically worsen the physical, psychological and social quality of life [1]. 1 in every 4 patients with diabetes develops complications. The pathogenesis of diabetics foot is due to two causes i.e. neuropathy and vasculopathy. Due to neuropathy the patient loses sensation whereas, vasculopathy causes poor blood supply to the foot region. Due to both these contributing factors, even a small trauma to the feet can give rise to ulcer or gangrene and may even require amputation. Thus, foot examination by a podiatrist or a doctor is recommended every year.
Historical Perspective
The discovery of the association between diabetes and foot ulceration and subsequent infection dates back to the 1850s. Significant breakthroughs in the management of diabetic foot wounds include the introduction of surgical debridement occurred in the early 1900s by Frederick Treves. He also introduced the critical role of footwear in diabetic foot ulcers. Furthermore the discovery of penicillin in 1928 by Alexander Fleming reduced the mortality rate of diabetic foot patients and their related complications significantly. Throughout the 20th century, advances in surgical limb revascularization and the advent of angioplasty drastically reduced the need for amputation. The latter method remained the mainstays of diabetic foot management, in the 2004 and 2012 Infectious Disease Society of America guidelines.
Classification
Diabetic foot is classified based on ulcer's features in order to assist with clinical decision-making regarding the need for oral or parenteral antibiotics, outpatient management, hospitalization, and surgical intervention. There are multiple methods of classification for diabetic foot. One of them that has been published by The Infectious Disease Society of America (IDSA) in their 2004 guideline and mainly has been focused on the extent of infection and inflammation of the ulcer. In addition another similar classification system has been released by The International Working Group on the Diabetic Foot (IWGDF) in 2012. The aforementioned systems were externally validated in a longitudinal study to assess prognostic value, which demonstrated increased risk for amputation among patients with infections classified as severe. Another widely accepted diabetic foot ulcer classification is Wagner ulcer classification system, which uses some ulcer's features such as depth, in addition to presence of osteomyelitis or gangrene.
Pathophysiology
Diabetic foot is an umbrella term for foot problems in patients with diabetes mellitus. Neuropathy, ischemia and trauma are three main pathogenesis of diabetic foot. Neuropathy is the most common and is responsible in more than 60% of diabetic foot cases. Factors such as high blood glucose, reactive oxygen species, insufficient oxygenation of the nerves and inflammation leads to neuropathy development is diabetic patients and get worse by alcohol use and smoking. Neuropathy can involve motor, autonomic or sensory nerves and is able to involve both large and small fibers. Motor nerve involvement can lead to some mechanical changes in the foot of a diabetic patient, which cause more plantar pressure and higher risk of callus formation. Each and every lead to higher rate of skin breakdown and ulceration. Autonomic neuropathy leads to anhidrosis and impaired function of oil glands, subsequent skin dryness, higher chance of skin breakdown and ulcer formation. Diabetic patients with sensory neuropathy are more prone to ulcer formation and related complications, since they don't feel pain with ever-deepening ulcers. Ischemia is the second best known pathogenesis of diabetic foot could occur due to a higher rate of lower limb atherosclerosis in diabetic patients, compared to normal population. Diabetes related complications such as Micro and macrovascular complications further intensify ischemia. Ischemic changes can be discovered by an impaired ankle brachial index (ABI). Trauma to the foot usually acts as a trigger for diabetic foot. A defective hypoxic response has been explained in diabetic foot, which is related to a transcription factor, named hypoxia‐inducible factor‐1 (HIF‐1). Lower level of HIF‐1 in biopsies of diabetic foot could be related to it's role in wound healing. Some genetic associations (such as MAPK14 gene located on chromosome 6, decreased expression of certain cytokines and growth factors, and the HSPA1B genotype) have been explained in diabetic foot development. Charcot arthropathy, some psychosocial conditions, necrotizing fasciitis (NF), vitamin D deficiency, tinea pedis, onychomycosis and diabetic retinopathy are associated conditions in diabetic foot. On gross pathology, the most common site of ulceration is on the sole of the feet, under the metatarsal head with various depth and possible anatomical deformities of foot. In microscopic evaluations of the ulcers evidences of necrosis, hyperkeratosis, fibrosis, inflammation, cellular debris, granulation tissue and angiogenesis have been found.
Causes
Conditions such as peripheral neuropathy and ischemia are two common causes of diabetic foot ulcer formation. Decreased sensation due to peripheral neuropathy increase the risk of trauma which is another known cause of ulcer formation. Microorganisms such as staphylococcus aureus, pseudomonas aeruginosa, proteus mirabilis, escherichia coli and bacteroides fragilis are responsible for diabetic foot ulcer infection.
Differentiating Diabetes foot other Diseases
Diabetic foot must be differentiated from other diseases that cause foot ulceration, erythema, swelling and skin lesion, such as skin and soft-tissue infections, gas gangrene, cellulitis, deep venous thrombosis and inflammatory disorders.
Epidemiology and Demographics
The incidence of diabetic foot ulcer is approximately 1500 per 100,000 diabetic individuals world wide. Just among the US veterans the incidence of active diabetic foot ulcers is approximately 500 per 100,000 individuals. On the other hand the incidence of active diabetic foot ulcers in United Kingdom has been estimated 220 per 100,000 individuals. Furthermore it's prevalence has been reported 170 per 100,000 individuals among the United Kingdom population. The 5 year risk of mortality in diabetic patients with a foot ulcer is 2.5 times higher than diabetic individuals without a foot ulcer. Based on 2 studies with different follow up duration, mortality rate of diabetic foot has been estimated as 10% and 24% in 16 months and 5 years follow up, respectively. Based on a systematic review and metanalysis done on diabetes patients, diabetic foot was more common among older patients. White people develop diabetic peripheral neuropathy (which is a serious risk factor for diabetic foot) more frequently. In 1987, Borch-Johnsen et al. described a male preponderance for the development of severe microvascular complications and diabetic foot disease is not an exception to this rule. Highest prevelance of diabetic foot has been reported in North America. In contrast Oceania has the lowest prevelance of diabetic foot.
Risk Factors
There are numerous risk factors for diabetic foot development in a diabetic patient, such as poor glycaemic control, inappropriate foot care and footwear, foot deformities, peripheral arterial disease, peripheral neuropathy, history of previous foot ulcer or amputation, infection, high body mass index and poor socioeconomic status. Other comorbidities such as hypertension and dyslipidemia are also responsible as risk factors for diabetic foot ulceration.
Screening
Natural History, Complications and Prognosis
Patients with diabetic foot have an increased risk of all-cause mortality, especially cardiovascular disorders, compared with patients with diabetes without a history of diabetic foot ulcer. The complications of diabetic foot ulcers include infection, sepsis, osteomyelitis and death.[2][3]
Diagnosis
History and Symptoms
Physical Examination
Laboratory Findings
Electrocardiogram
Chest X Ray
CT
MRI
Echocardiography or Ultrasound
Other Imaging Findings
Other Diagnostic Studies
Treatment
Medical Therapy
Appropriate wound care is essential for the management of all diabetic foot ulcers. Uninfected diabetic ulcers do not require antibiotic therapy. For acutely infected wounds, empiric antibiotic with efficacy against Gram-positive cocci should be initiated after obtaining a post-debridement specimen for aerobic and anaerobic culture. Infections with antibiotic-resistant organisms and those that are chronic, previously treated, or severe usually require broader spectrum regimens.
Surgery
Primary Prevention
The primary prevention of diabetic foot ulcer includes control of blood sugar levels , pressure offloading, frequent physical examinations, good foot hygiene, diabetic socks and shoes, and by avoiding injury.
Secondary Prevention
The secondary prevention of diabetic foot ulcer includes pressure offloading, prevention of infection, treatment of infection, debridement and reconstruction of the damaged blood vessels, along with the use of primary preventive strategies.[3]
Cost-Effectiveness of Therapy
Future or Investigational Therapies
Case Studies
Case #1
References
- ↑ Assal JP, Mehnert H, Tritschler HJ, Sidorenko A, Keen H, Hellmut Mehnert Award Workshop Participants (2002). "On your feet! Workshop on the diabetic foot". J Diabetes Complications. 16 (2): 183–94. PMID 12039404.
- ↑ Brownrigg JR, Davey J, Holt PJ, Davis WA, Thompson MM, Ray KK; et al. (2012). "The association of ulceration of the foot with cardiovascular and all-cause mortality in patients with diabetes: a meta-analysis". Diabetologia. 55 (11): 2906–12. doi:10.1007/s00125-012-2673-3. PMID 22890823.
- ↑ 3.0 3.1 Armstrong DG, Boulton AJM, Bus SA (2017). "Diabetic Foot Ulcers and Their Recurrence". N Engl J Med. 376 (24): 2367–2375. doi:10.1056/NEJMra1615439. PMID 28614678.