Outpatient vs. Inpatient Workup of Diabetic Foot Infections
By: Marisse Lardizabal, DPM,
Diabetic foot infections (DFI) are both challenging and common amongst all podiatrists. Treatment of DFI’s require a level of comfort and training as well as resources available to clinicians. ABPM has traditionally been a great source of information for podiatrists which makes the board certification by ABPM paramount. Like many podiatrists, you may encounter these types of patients initially in the clinic/outpatient setting, where you can catch the potential signs and symptoms of a diabetic foot infection waiting to happen.
First, nothing can substitute a thorough History and Physical Exam on a patient. A complete NLDOCAT will give one a lot of information as well as develop a story as to why the patient is presenting with a diabetic foot infection. For example, time frame of the ulceration, how well the patient’s diabetes is controlled, and any prior and/or current ulcerations will help you formulate a treatment plan. This may also foreshadow how compliant a patient will be with their recovery. A thorough physical exam is of significant value when looking for classic clinical signs of infection, as well as the status of the neurovascular structures. Does the patient have enough circulation to heal an ulcer? Is a referral to a vascular surgeon necessary? Obtaining radiographs and necessary labs (CBC, CMP, ESR, CRP) should be obtained for a complete work up.
The Infectious Disease Society of America Diagnosis and Treatment of DFI, also known as IDSA Classification, is one of the most helpful guidelines that should be utilized by clinicians who treat DFI routinely. This guideline classifies DFI based on severity of the infection, clinical signs, and constitutional symptoms presented. IDSA also makes recommendations of what the appropriate treatment course should be. For example, consider a patient who presents with erythema <2 cm around the ulcer with 2+ signs of infection. According to the IDSA guidelines, the patient’s infection is classified as “uncomplicated soft tissue infection” or Mild DFI. Therefore one may feel comfortable sending the patient home with oral antibiotics, local wound care and offloading as well as a 3-5 day follow up to see if the signs of infection have resolved.
Moderate DFIs (erythema > 2cm with 2+ signs of infection present) are the most challenging to classify and treat. Without close observation, these patients can potentially get worse and can be very much considered as admitting criteria depending on presentation of the infection. At times, these patients can benefit from a decompression of the infected foot in the clinic setting, while making sure wound cultures are obtained prior to discharge. If patients are discharged home, close follow up and monitoring is essential. If symptoms do not improve, the safest course of treatment may be hospital admission for IV antibiotics and possible surgical interventions.
Lastly, severe DFIs are complicated local infections in conjunction with the patient endorsing constitutional symptoms as well as presence of SIRS criteria. These are the patients that will be admitted to the hospital for surgical management of the infection due failure of conservative treatment. The IDSA guidelines are key elements to be familiar with as they will guide your treatment and tell you which patient will need a higher level of care.
Once the patient is admitted to the hospital, inpatient work up of DFI is very much similar to the outpatient setting. If admitting the patient under Internal Medicine, it is important to communicate necessary labs, imaging, choice of IV antibiotics, NPO status as well as plan for surgical intervention to the service for an efficient and effective hospital course. One may consider advanced imaging, such as an MRI (preferably prior to surgical intervention), whether there is concern for osteomyelitis or abscess in the foot. The advanced imaging should by no means delay surgical intervention if it is considered emergent.
This brief overview of triaging DFIs can hopefully streamline how DFIs are treated in one’s practice. Effective treatment of DFIs is our expertise and it will benefit our patients to have a standard of how it is treated. Being board certified by ABPM, I feel confident in treating DFIs with the knowledge and background that I continually use in my daily career as a Podiatrist.
Clinical Infectious Diseases, Volume 54, Issue 12, 15 June 2012, Pages e132–e173, https://doi.org/10.1093/cid/cis346