diabetic foot infections

Diabetic Foot Infections : 

Diabetic Foot Infections

Overview : 

Overview Introduction Epidemiology Etiology Pathophysiology Microbiology Assessment Classification Treatment Follow-Up

Introduction : 

Introduction One in every six people with diabetes will have a foot ulcer during their lifetime Every year 4 million people with diabetes will develop a foot ulcer Every 30 seconds a leg is lost due to diabetes somewhere in the world Foot problems are the most common cause of admission to hospital for people with diabetes In developing countries foot problems may account up to 40% of health care resources The direct cost of an amputation is estimated to be between $30,000 and $ 60,000 Ulcers can be prevented and up to 85% of amputations can be avoided

Epidemiology : 

Epidemiology Young adults, early middle age, but not uncommon in juvenile diabetics Females > males Uncontrolled diabetes increases risk Poor foot hygiene

Etiology : 

Etiology Local bacterial invasion Typically polymicrobic Staphylococci and streptococci most common pathogens Gram-negative bacilli and/or anaerobes occur in about 50% of cases Peripheral neuropathy is responsible for the "diabetic foot" Other factors are angiopathy, atherosclerosis, and infection and most often they are combined

Pathophysiology : 

Pathophysiology Complications of diabetes that affect the lower extremities include: Peripheral neuropathy sensory autonomic motor Peripheral arterial disease reduced blood supply to feet and legs Trauma acute- burns or cuts chronic- foot deformities

Pathophysiology : 

Pathophysiology

Microbiology : 

Microbiology Deep abscesses Cellulitis Infected diabetic “mal perforans” ulcers

Clinical Assessment : 

Clinical Assessment GENERAL EXAMINATION The leg and foot are inspected for overall appearance of the skin, hair growth, perfusion, pulses, and color erythema warmth tenderness swelling visible pus FOOT EXAMINATION bony prominences presence of protective sensation ulcers should be evaluated for infection in the adjacent soft tissues wounds should be measured for length, width, depth and location open wounds should be probed with a sterile cotton swab or other appropriate instrument to evaluate the extent of involvement of deeper structures (tendons, joints, and bone)

Diagnosis : 

Diagnosis Wound culture X-ray especially bones; to determine if there is evidence of infection in the bones CT scan to evaluate a suspected pocket of pus called an abscess MRI to evaluate a suspected pocket of pus called an abscess Doppler or arteriographic studies to assess for adequate blood flow to feet, which is necessary for healing Complete blood count to determine if there is an infection

Management : 

Management An interdisciplinary network is required to assess, prevent and manage diabetes foot complications Core team members should include: Family Practitioner Diabetes Specialist or Nurse Practitioner Chiropodist/Podiatrist Diabetes Educators Orthotist/Podiatrist Orthopedic or Vascular Surgeon

Classification : 

Classification

Treatment : 

Treatment Primary goal of treatment  to obtain healing as soon as possible the faster the healing, the less chance for an infection There are several key factors in the appropriate treatment of a diabetic foot ulcer: Prevention of infection Taking the pressure off the area, called “off-loading” Removing dead skin and tissue, called “debridement” Applying medication or dressings to the ulcer Managing blood glucose and other health problems

Treatment : 

Treatment Avoid using antibiotics in uninfected ulcerations Determine the need for hospitalization Stabilize the patient Choose an antibiotic regimen Determine the need for surgery Formulate a wound-care plan Adjunctive treatments

Treatment : 

Treatment Avoid using antibiotics for uninfected ulcerations Antibiotic use increases antimicrobial resistance, increases the cost of treatment, and may potentially cause adverse effects Antibiotic therapy for uninfected ulcers is not recommended Determine the need for hospitalization Most expensive component of treatment Severe infections or infections complicated by limb ischemia should be hospitalized Patients with mild – moderate infections may need to be hospitalized for observation, diagnostic testing, or other complications Without these factors, mild-moderate patients can be treated as outpatients Stabilize the patient Attend to the patient’s general metabolic state Restoration of fluid and electrolyte balances Correction of hypoglycemia, hyperosmolality, and acidosis

Treatment : 

Treatment Antibiotic Therapy Indications for therapy Route of therapy Choice of antibiotic agents Duration of therapy

Treatment : 

Treatment Suggested Empirical Antibiotic Therapy

Treatment : 

Treatment Empiric antibiotic regimen should include an agent active against Staphylococcus aureus, including MRSA Coverage for aerobic gram-negative pathogens is required for severe infection, chronic infection, or infection that fails to respond to recent antibiotic therapy Initial empiric antibiotic therapy should be modified on the basis of the clinical response and culture or susceptibility testing Diabetic patient with chronic foot wounds that have received multiple prolonged antibiotic treatments are at risk for developing VRSA

Treatment : 

Treatment Wound Classification Wound Care Arterial inflow is adequate Infection is treated appropriately Pressure is removed from the wound and the immediate surrounding area

Treatment : 

Treatment Adjuvant Therapies Recombinant granulocyte-colony stimulating factor (GCSF) Amputation Revascularization Larval (maggot) therapy Edema control

References : 

References Centers for Disease Control and Prevention: National Diabetes Surveillance System. Available online at: http://www.cdc.gov/diabetes/statistics/index.htm. Retrieved 9/2/2010. International Journal of Lower Extremity Wounds 2010 9: 127 Sanjeev Kumar Gupta, Satyajit Panda and Surya Kumar SinghThe Etiopathogenesis of the Diabetic Foot: An Unrelenting Epidemic Justin J. Sherman. Diabetic Foot Ulcer Assessment and Treatment: A Pharmacist’s Guide. US Pharm. 2010;35(6):38-44.  Jeffcoate WJ, Harding KG. Diabetic foot ulcers. Lancet. 2003; 361: 1545-51. Frykberg RG. Disorders of the foot and ankle. In Noble, ed. Textbook of Primary Care Medicine. St. Louis: Mosby Inc. 2001:1206-1225. Clayton W, Elasy, T. A Review of the Pathophysiology, Classification, and Treatment of Foot Ulcers in Diabetic Patients. Clinical Diabetes. 2009; 27: 2. Marion, DW. Diaphragmatic pacing. In: UpToDate, Basow, DS (Ed), UpToDate, Waltham, MA, 2010.