Treatment of Diabetic Bullae
Diabetic bullae should be deroofed immediately and then managed as diabetic foot ulcers using standard wound care principles: sharp debridement, basic moisture-retaining dressings, strict glycemic control with attention to hypoglycemia, and appropriate offloading. 1
Immediate Management
Deroofing the Bullae
- Remove the blister roof (deroof) to examine the base and prevent progression to chronic ulceration 1
- This allows direct assessment of the wound bed and prevents accumulation of fluid that can become infected 1
- After deroofing, treat the resulting wound as a diabetic foot ulcer 1
Glycemic Control
- Aggressively correct hyperglycemia with insulin therapy, as hyperglycemia delays wound healing through osmotic diuresis, decreased oxygenation, and impaired neutrophil function 2
- Pay special attention to hypoglycemic episodes, which are associated with bullae eruption in 83% of cases (29 of 35 outbreaks) 1
- Monitor for highly varying blood glucose levels at the time of eruption 1
Standard Wound Care Protocol
Debridement
- Perform sharp debridement to remove necrotic tissue, debris, and surrounding callus as the standard of care 2, 3
- The frequency of sharp debridement should be determined by clinical need 4, 3
- Avoid surgical debridement when sharp debridement can be performed outside a sterile environment 4, 2
Dressing Selection
- Use basic wound dressings that absorb exudate and maintain a moist wound healing environment 4, 3
- Do NOT use topical antiseptic or antimicrobial dressings routinely for wound healing purposes 4, 2, 3
- Apply non-adherent dressings to denuded dermis 2
- Re-evaluate dressings daily, ideally 2
Infection Management
- Administer systemic antibiotics ONLY when clinical signs of infection are present (erythema, warmth, swelling, tenderness, or purulent discharge) 2
- Antibiotics were required in approximately 49% of bullae episodes (17 of 35) 1
- Obtain wound cultures before initiating antibiotics if infection is suspected 4
- Do NOT use antibiotics prophylactically for uninfected wounds 4, 2
Offloading
- Use a non-removable knee-high offloading device as first-line treatment for plantar lesions 3, 5
- For patients with limited access to specialized devices, consider felted foam with appropriate footwear 3, 5
- Protective footwear is essential during the healing phase 1
Expected Healing Timeline and Complications
Healing Duration
- Median healing time is 2.5 months (range 0.5-23 months), which is considerably longer than typical acute wounds 1
- Diabetic bullae can progress to chronic foot ulcers with serious complications if not managed properly 1
Potential Complications
- Minor amputations occurred in 8% of patients (2 of 25) in one series 1
- The mortality risk increases more than twofold when diabetic wounds are present 6
Adjunctive Therapies for Non-Healing Wounds
If the wound fails to show sufficient improvement after 2 weeks of standard care 3:
Consider These Options
- Sucrose-octasulfate impregnated dressing for non-infected, neuro-ischemic wounds (conditional recommendation, moderate certainty) 4, 3
- Autologous leucocyte, platelet, and fibrin patch where resources exist for regular venepuncture (conditional recommendation, moderate certainty) 4, 3
- Hyperbaric oxygen therapy for neuro-ischemic or ischemic wounds where standard care has failed and resources exist (conditional recommendation, low certainty) 4, 3
Critical Pitfalls to Avoid
- Do NOT leave bullae intact - deroofing is essential to prevent chronic ulceration 1
- Do NOT overlook hypoglycemia as a precipitating factor - investigate glucose variability at time of eruption 1
- Do NOT use collagen, alginate, honey, or herbal dressings - these have strong recommendations against use 4
- Do NOT delay offloading - this is a common cause of treatment failure 3
- Recognize that diabetic bullae are not as rare or benign as traditionally thought, with an incidence of 0.16% per year in diabetic populations 1