Last week, I had a medical representative come into the wound care center to see the use of one of her company’s products on a patient I was treating. While I was examining the patient, she expressed curiosity at the proud flesh granulation tissue she saw on the venous stasis ulcer. After telling her that it was hypergranulation tissue, she went on to ask why it develops. Accordingly, for this blog, I thought it would a good idea to review and discuss the underlying etiology, treatment and prevention of hypergranulation tissue.
Hypergranulation, which is also known as overgranulation, exuberant granulation tissue or proud flesh, usually presents by secondary intention in the wound healing process. Granulation tissue is comprised of new connective tissue and tiny blood vessels that form on the surfaces of a wound during the healing process. Prolonged stimulation of fibroplasia and angiogenesis results in hypergranulation, which can be a potential problem for the wound healing process.
Hypergranulation prevents epithelialization and the healing process may be arrested. The point at which hypergranulation tissue replaces normal healthy granulation tissue has not been clearly defined but we can speculate that epithelialization stops and the healing process is halted. This is a result of the nature of the hypergranular tissue, which impedes epithelial migration.
Hypergranulation physically impedes epithelial cell movement (raised rolled overgrowth) or, as a result of changes in extracellular signaling, switches off the movement of epithelial cells. This exact mechanism is unclear. The wound generally will not heal when there is hypergranulation tissue because it will be difficult for epithelial tissue to migrate across the surface of the wound and contraction will be halted at the edge of the swelling.
In regard to clinical recognition, hypergranulation has a friable red, sometimes shiny and soft appearance that is above the level of the surrounding skin. While there is limited research on the cause of hypergranulation tissue, clinicians have identified a few common characteristics. These characteristics include:
• moist areas from exudates or bleeding
• prolonged physical irritation or friction with continued repetitive minor trauma or pressure
• excessive inflammation
• bacterial bioburden or infection
• a new scenario of negative pressure suction with microdeformation, particularly applicable to large pore foam dressings
• low oxygen levels
Additionally, patients with diabetes are very prone to clinical wound infection due to the inadequate delivery of oxygen and nutrients to the wound bed, which increases the potential for abnormal tissue such as hypergranulation tissue. Also keep in mind that overuse of occlusive dressings is thought to have an influence as it creates a hypoxic environment that causes the body to produce more blood vessels but some of those are immature blood vessels to compensate.
Differentiating Between Hypergranulation Tissue And Malignancy
Clinicians may mistake a malignancy for overgranulation. If there is any suspicion that this is not normal, one should obtain a biopsy. There will be some clinical clues.
• The overgranulation has been present for many months.
• It has a cauliflower appearance or is hard to touch.
• It is growing outward beyond the wound margins.
• It does not respond to any of the treatments below.
Possible Treatment Options For Hypergranulation Tissue
• Silver nitrate. When activated, this is a caustic material that oxidises organic matter, coagulates tissue and destroys bacteria. Tissue dies almost immediately. Unfortunately, this sets up further inflammation and exudate formation.
• Vapor permeable dressing. A non-occlusive dressing, such as a foam dressing, with light pressure application can be effective.
• Hypertonic NaCl dressing products, such as Mesalt® (Molnlycke Health Care)or Curasalt® (Medline), use oncotic pressure to promote drying by managing exudates, promoting movement of fluid away from the wound and reducing tissue edema.
• Sharp debridement of the area is extremely successful at removing the hypegranulation tissue but not successful at preventing recurrence.
• Low-dose cortisone cream or tape to promote collagen breakdown Topical corticosteroids are not approved or indicated for open wounds or hypergranulation tissue. This method of treatment is rarely successful.
• Surgical lasers. These devices not only remove overgranulation tissue but also cauterize small blood vessels. They are very selective, leaving healing cells alone.
Please feel free to provide any further insights from your clinical experience in the comment section below.
Resources
1. Widgerow AD, Leak K. Hypergranulation tissue: evolution, control and potential elimination. Wound Healing Southern Africa. 2010;3(2):1-3. Available at: www.woundhealingsa.co.za/index.php/WHSA/article/viewFile/87/127
2. Stephen-Haynes J. Achieving effective outcomes in patients with overgranulation. Wound Care Alliance UK. Available at: www.wcauk.org/downloads/booklet_overgranulation.pdf