Diabetic Foot Screening: How to Manage A Diabetic’s Worst Nightmare?

Diabetes is a growing epidemic in our nation and globally. The prevalence of diabetes among Singapore residents (Singapore citizens and Permanent Residents) has increased over the decade. In Singapore,it is estimated that 1 in 9 adults has diabetes1. Today, there are over 450,000 Singaporeans living with diabetes. This number is projected to go up to 1 million by 2050, if nothing is done2.The Ministry of Health (MOH) launched the War on Diabetes in 2016, in response to the significant health and societal burden posed by diabetes. The cost burden of diabetes, including loss to productivity, is anticipated to double from S$940 million in 2014 to S$1.8 billion in 20503.

People with diabetes are at high risk of developing a range of serious complications, including heart disease, kidney failure, blindness, and lower-extremity complications. The most disabling of these is the lower limb complications. It is the leading cause of diabetes-related reason for hospitalization and lower limb amputation. In addition to high healthcare costs, it is also associated with significant reduction in quality of life4-5.

Diabetes Complications

Approximately 25% of diabetics will develop a foot wound or ulcer in their lifetime. Amputation in people with diabetes is 10 to 20 times more common than in people without diabetes⁶.Every year, more than one million of leg amputations are performed globally because of diabetes, which is equivalent to one leg amputation every 30 seconds⁷.

In a person with diabetes, higher than normal sugar levels in the body will over time damage nerves (neuropathy)⁸ and cause blood vessels of the leg and foot to narrow and harden (atherosclerosis) leading to reduced blood flow down to the feet (Peripheral Arterial Disease (PAD))⁹.

1. 1. Diabetic neuropathy⁸– This can result in:

      1. Poor sensation in the feet- Minor injuries to the foot can be left undetected because of poor sensation and may consequently lead to foot ulceration and infection.

      2. Foot deformities- Structural changes in the foot such as hammertoes, claw toes, collapse of the midfoot (Charcot foot)and limited joint mobility can result in focal areas of high pressure on the sole. Skin can breakdown over pressure points leading to ulceration.

      3. Decreased sweating- Nerves supplying the sweat glands stop functioning, leading to dry, flakyand cracked skin.Cracked skinin the foot may allow bacteria to enter and cause infection.

   2. Peripheral Arterial Disease (PAD)⁹–People with diabetes are at increased risk of atherosclerosis which narrows and harden the blood vessels of the leg and within the foot. Poor blood supply to the foot will lead to poor healing and gangrene as well as reduced ability to fight infection.

      
      Atherosclerosis with narrowing of artery

      Here are some statistics of diabetic peripheral arterial disease¹⁰:

      • 70% of diabetic wounds have associated PAD

      • Nearly 85% of diabetes-related amputations are preceded by an ulceration. This imply that majority ofthe amputations can be prevented.

      • Two-thirds of elderly patients undergoing amputation do not return to independent life

      • About 70% of amputees will die within 5 years

   3. Immunocompromised¹¹– Poor immune system reduces the ability to combat infection. Small injuries to the foot such as cuts, blisters and ingrown toenails can become infected easily if left untreated. The combination of neuropathy, PAD and poor immunityis responsible for the increased risk of developing foot complications such ulcers, gangrene and infection which may eventually lead to leg amputation if treatment is not sought early.

   
   Skin cracks

   
   Callus

   Diabetic foot deformity Photos

   

   

   Hammer toes

   

   

   Claw toes

   

    

   Flat foot

   

   Amputation

   

   Diabetic Foot Wounds/ Ulcers

   

   Gangrene

   

   Infected Wounds

   

   Neuropathic/Pressure Ulcers

   Management of Diabetic Foot Complications

   It is important to recognize that most diabetic foot complications are manageable and amputation can be prevented if treatment is sought early.Delayed in treatment of diabetic foot complications is common. The main reasons are underestimation of the severity of foot problems and lack of recognition of poor circulation¹². Management of diabetic foot problemsis often complex and experts from other specialties may need to be involved, including vascular/ endovascular surgery, diabetology and podiatry.

   Successful management of diabetic foot ulcers/wounds hinges on addressing the following treatment modalities:

   1. Ensure adequate blood supply to the foot- Every foot ulcer/wound should be examined for the presence of ischaemia. If poor circulation of the foot is suspected, investigations such as ultrasound scan or CT angiogram are required to assess the nature of the blockage in the leg arteries. The procedures to improve blood supply to the leg include surgical bypass or endovascular techniques (balloon angioplasty with or without stent)¹³. The treatment of choice depends on the specific type of blockage and which artery is involved and thegeneral health condition of each patient.

      

   2. Control of infection- Signs of wound infection may include:

      1. Peri-wound redness/ swelling

      2. Foul smelling wound

      3. Pus

      4. Pain

      Systemic signs of infection may include fatigue, fever, tachycardia (increased in heart rate), and general malaise. When infection is present clinically, cultures should be obtained. Antibiotics that are shown to be effective against the offending bacteria through sensitivity testing should be given either orally or intravenously, depending on the severity of the infection.

      For severe wound infection with significant tissue destruction involving muscle, tendon and bone; urgent surgical intervention will be needed to control the spread of infection.

   3. Wound care

      1. Debride all non-viable tissue (e.g. callus, foreign bodies and necrotic tissue) that may impede wound healing

      2. Appropriate dressing choice to ensure moist wound environment for healing.

      3. Antimicrobial dressings need to be considered to treat and prevent wound from infection

   4. Offloading- redirecting weight (or pressure) off and away from the wound with proper footwear. Some patients may require wheelchair or crutches to achieve effective offloading.

   Prevention

   1. Management of risk factors

      1. Blood sugar level- High blood sugar, the hallmark of diabetes, injures nerves and blood vessels throughout the body.

      2. High blood pressure- high blood pressure damages blood vessels, leading to atherosclerosis

      3. High cholesterol level- accumulation of cholesterol-rich fatty deposits in arteries can result in atherosclerosis.

   2. Lifestyle modification

      1. Smoking cessation- Smoking interferes with blood circulation, and so compounds the effects of nerve and blood vessel damage.

      2. Exercise- naturally improves circulation while working to lower cholesterol and improve heart function.

      3. Healthy diet- Steering clear of excessive amounts of salt and saturated fats can help you manage your body weight, blood pressure and cholesterol.

      4. Weight loss- losing weight improves the body’s ability to control blood sugar and it also takes some pressure off the feet.

   3. Foot Care

      1. Check your feet and toes every day for cuts, sores, corns or blisters

      2. Never go barefoot. Choose shoes that are comfortable and fit well.Ill-fitting shoes can cause corns and calluses, ulcers and nail problems.

      3. Wash feet daily. Apply moisturising skin lotion to feet to prevent dryness and cracks.

      4. Cut or file your toenails regularly.

      5. Yearly foot screening by podiatrist, doctor or trained nurse- Early identification of those at risk of diabetic foot ulcers will prevent development of foot complications and thus reduce the number of amputations.Education on proper foot care and good glycaemic (blood sugar level) control

      

   Finally, if there are symptoms of unusual pain, redness in the foot, swelling, injury to the foot, infection or ulcer; make sure this is checked by your doctor or diabetic nurse as soon as possible. There is a clear need to recognise decreased perfusion or vascular impairment as an indicator for the need for revascularisation in the diabetic foot in order to achieve and maintain healing and to avoid or delay a future amputation.Early identification of the problem and treatment before the problem becomes severe is CRITICAL in preventing limb loss.

    

   Dr Tan YIH KAI
   Consultant Surgeon (Vascular and Endovascular Surgery)
   Farrer Vascular, Vein and Wound Centre
   Farrer Park Medical Centre
   1 Farrer Park Station Road
   #13-11 Connexion, Singapore 217562

    

   References

   • Information Paper on Diabetes in Singapore.Vol6 2016 https://www.nrdo.gov.sg/docs/librariesprovider3/default-document-library/diabetes-info-paper-v6.pdf?sfvrsn=0. Accessed 28 Oct. 2020

   • Ministerial Conferenceon Diabetes to Tackle Global Diabetes Epidemic. 25^th Nov 2018
     https://www.moh.gov.sg/news-highlights/details/ministerial-conference-on-diabetes-to-tackle-global-diabetes-epidemic. Access 28 Oct 2020

   • Singapore’s War on Diabetes. 30 Aug 2018

     https://www.ourcommons.ca/Content/Committee/421/HESA/Brief/BR10093093/br-external/MinistryOfHealth-Singapore-e.pdf. Accessed 28 Oct 2020

   • SinghN, ArmestrongDG, LipskyBA. (2005) Foot ulcer in patients with diabetes. JAMA. 293(2):217–228.

   • FrykbergRG, ZqonisT, ArmstrongDG, et al.(2006) American College of Foot and Ankle Surgeons. Diabetic foot disorders: a clinical practiceguideline (2006 revision). J Foot Ankle Surg. 45(5 Suppl):S1–S66.

   • International Diabetes Federation. IDF Diabetes Atlas, 8th ed. Brussels, Belgium: International Diabetes Federation, 2017.

   • BakkerK, FosterAVM, van HoutoumWH, Riley P (Eds). International Diabetes Federation and International Working Groupof the Diabetic Foot. Time to act. The Netherlands. 2005

   • Pop-BusuiR, BoultonAJM, etal. (2017)Diabetic Neuropathy: A Position Statement by the American Diabetes Association Diabetes Care. 40:136–154

   • American Diabetes Association. (2003) Peripheral Arterial Disease in People with Diabetes. Diabetes Care. 26(12): 3333-3341

   • MavrogenisA F, MegaloikonomosP D, AntoniadouT, etal. (2018) Current concepts for the evaluation and management of diabetic foot ulcers.EFORT Open Rev. 3(9): 513–525.

   • BerbudiA, RahmadikaN, TjahjadiA I, and RuslamiR. (2020)Type 2 Diabetes and its Impact on the Immune System. Curr Diabetes Rev. 16(5): 442–449.

   • ManuC, LacopiE,BouilletB, etal. (2008) Delayed referral of patients with diabetic foot ulcers across Europe: patterns between primary care and specialised units. Journal of Wound care. 27(3): 186-192

   • HeikkinenM, SalmenperäM, LepäntaloA, LepäntaloM. (2007) Diabetes Care for Patients with Peripheral Arterial Disease.European Journal of Vascular and Endovascular Surgery.33(5): 583-591.