Chronic Wound, Non-Healing Wounds | MicroGen Diagnostics

Chronic Wound, Non-Healing Wounds

A chronic wound can be a sore or cut that doesn’t heal normally. It could be the result of several things, including traumatic injury, poor circulation, increased bacteria count, abnormal cells, or improper treatment. A wound is generally considered chronic if it’s shown no serious progress toward healing after 30 to 40 days. In fact, some chronic wounds can take years or decades to heal.

According to the National Institutes of Health, 80% of wound infections are due to biofilms. These are thin layers of bacteria that hold together and stick to surfaces in the body. Because biofilms are difficult to get rid of, they can interfere with wound healing and a wound can remain inflamed. A wound may become chronic and not heal due to a biofilm. Using a molecular diagnostic approach such as a MicroGenDX test to diagnose and treat a wound with a biofilm makes a major difference. Using MicroGenDX for treatment and diagnosis has shown improved healing rates of 21% to 25%. In short, you’ll get better faster.

Chronic leg and foot ulcers are common examples of chronic wounds, often affecting adults with vascular disease or diabetes. An estimated 2.4–4.5 million people in the United States experience these types of ulcers, which can reappear in up to 70% of patients.

Chronic Wound Infection Symptoms

Common symptoms of chronic wounds include:

  • Pain, bleeding, or blistering
  • Skin redness and swelling
  • Skin darkening or discoloration with open sores
  • Shiny, smooth appearance to the skin, which often feels warm, dry, and itchy

MicroGenDX Tests Used in Diagnosing Chronic Wounds

Growing microbes from your sample in a lab – usually known as a culture – is often used to diagnose chronic wound infections. However, standard cultures might come back negative even when you actually have an infection – or culture results may come back with bacteria that may be present in the wound, but not actually causing the infection. And that means your infection won’t be treated. With a MicroGenDX test, the DNA of all microbes in your wound sample can be detected. The test will show how much of each microbe is present and will use that information to identify causes of the infection.

To get complete instructions, you can order that WoundKEY test here:

Providing a Sample for the Chronic Wound Infection Test

Everything you need to know about how chronic wound samples are taken is included with the WoundKEY test. It’s also available online on the product page. The instructions included with your test contain illustrations that will help you assist your doctor in collecting a sample without contaminating it. To obtain a proper sample, it’s important to follow the instructions for collecting the sample, as well as packaging and shipping it. For example, be sure not to contaminate the sample by touching it with your hands. For best results, you must be off all antibiotics for two days before the sample is collected. However, if this isn’t possible, the test can still be run.

Your doctor will use one of two methods to provide a sample for this test: the swab method or “debridement,” which is the surgical removal of dead or contaminated tissue. Both methods start by using gauze and saline to lightly wipe the surface area to remove dead skin and tissue.

For the swab method, your doctor will roll the swab over the entire surface area of the wound, applying pressure as it moves across the wound. As much material as possible needs to be gathered on the swab to ensure a conclusive sample. Then the swab will be inserted into the specimen tube.

For the debridement method, your doctor might use a numbing agent such as injectable Lidocaine for your comfort. Then your doctor will collect the sample by scraping the entire surface of the wound. There might be a little bit of bleeding. If possible, your doctor will collect samples from all areas of the wound to ensure a full and accurate sample, and then transfer the sample into a specimen vial.

Medical Specialties That Treat Chronic Wound Infections

Your first contact for treatment is your primary care physician. For advanced care, a wound care specialist should be consulted. Most chronic wound care procedures recommend the use of advanced therapies after four weeks for non-healing wounds.

How Chronic Wound Infections Are Treated

Chronic wound infections are treated with antibiotics or antifungals that may be taken orally, applied topically on the surface of the wound, or both. How long and how often you take or apply the antibiotic or antifungal will depend on which types your doctor prescribes. It is important to complete the full course of medication as it is prescribed, even when a wound seems to be healing well.

Some bacteria that cause chronic wound infections can also develop resistance to specific antibiotics, which means that the infection can’t be effectively treated with those antibiotics. This is why all MicroGenDX diagnostic tests include detection of antibiotic resistance genes in your sample, and then provide alternative antibiotics for your doctor to consider prescribing to you.

It’s critical to know what microbes (fungi and bacteria) are present in wounds that won’t heal, and qPCR+NGS reveals exactly that. Molecular testing like qPCR+NGS is 20 times more precise than other methods when identifying the species of microbes involved in your wound’s infection, which allows your doctor to select the most appropriate treatment options. Your doctor should consult the "antimicrobials for consideration" chart on your MicroGenDX report to decide what antibiotic or antifungal is right for you.


  1. Brownrigg JR, Apelqvist J, Bakker K, Schaper NC, Hinchliffe RJ. Evidence-based management of PAD & the diabetic foot. Eur J Vasc Endovasc Surg 2013;45:673–681
  2. Richmond NA, Maderal AD, Vivas AC. Evidence-based management of common chronic lower extremity ulcers. Dermatol Ther2013;26:187–196
  3. Järbrink K, Ni G, Sönnergren H, et al. The humanistic and economic burden of chronic wounds: a protocol for a systematic review. Syst Rev. 2017;6(1):15.
  4. Optimal Care of Chronic, Non-Healing, Lower Extremity Wounds: A Review of Clinical Evidence and Guidelines [Internet]. Ottawa (ON): Canadian Agency for Drugs and Technologies in Health; 2013 Dec 17. Available from:
  5. Wolcott RD, Cox SB, Dowd SE, Healing and healing rates of chronic wounds in the age of molecular pathogen diagnostics, Journal of Wound Care, , Vol 19, No 7, July 2010
  6. Davies D. Understanding biofilm resistance to antibacterial agents. Nat Rev Drug Discov. 2003;2(2):114–122.
  7. Lebrun E, Kirsner RS. Frequent debridement for healing of chronic wounds. JAMA Dermatol. 2013;149(9):1059.

Show References

Translate »
Shopping cart0
There are no products in the cart!
Continue shopping