Clinical Scorecard: Autologous Fat Transfer: A Promising Approach for Treating Complex Anal Fistulas
At a Glance
Category
Detail
Condition
Complex anal fistulas, including those associated with Crohn’s disease
Key Mechanisms
Use of autologous fat grafts containing adipose-derived stem cells to promote healing by targeting inflammation, infection, epithelialization, and nonhealing tissue
Target Population
Patients with complex anal fistulas, including Crohn’s disease patients often refractory to standard treatments
Care Setting
Surgical and outpatient settings at academic institutions with plastic surgery and colorectal expertise
Key Highlights
Anal fistulas affect 20,000–25,000 new patients annually in the USA, with high recurrence and nonhealing rates especially in Crohn’s disease.
Autologous fat grafting (AFG) leverages adipose-derived stem cells to improve healing potential in complex wounds including anal fistulas.
AFG procedure involves harvesting, processing, and injecting lipoaspirate around the fistula tract with careful surgical technique to promote closure and reduce recurrence.
Guideline-Based Recommendations
Diagnosis
Clinical exam including fistula probing and assessment of drainage and pain.
Radiologic imaging as needed to confirm fistula anatomy and closure.
Use of Perianal Disease Activity Index (PDAI) scores to assess disease severity and treatment response.
Management
Control local sepsis and place setons 6–12 weeks prior to AFG if necessary.
Harvest subcutaneous fat under general anesthesia using tumescent infiltration and manual liposuction.
Process lipoaspirate by gravity separation or using the REVOLVE system for washing and filtering.
Debride fistula tract to healthy tissue, close internal opening with absorbable sutures, and inject fat graft around internal orifice and tract.
Prescribe 1-week oral antibiotics and stool softeners postoperatively.
Monitoring & Follow-up
Assess clinical improvement by reduction in pain and drainage impacting quality of life.
Evaluate clinical closure by absence of drainage, pain, seton, and visual closure of external orifice on exam.
Monitor for fistula recurrence defined as persistence or symptomatic fistula requiring intervention within 3 months.
Track fecal incontinence excluding patients with stomas.
Risks
Potential abscess formation if large bolus fat injections (>1 mL) are used.
Risk of recurrence and nonhealing especially in Crohn’s disease patients.
Minimal risk of worsening fecal incontinence reported.
Patient & Prescribing Data
Patients with complex anal fistulas including Crohn’s disease patients often refractory to standard surgical and medical treatments
AFG shows promising healing rates and safety profile comparable to more expensive lab-expanded stem cell therapies, with potential to reduce recurrence and improve quality of life.
Clinical Best Practices
Ensure local sepsis control and appropriate seton placement prior to AFG.
Minimize local anesthetic use during graft injection to avoid graft toxicity.
Use careful surgical technique to debride fistula tract and close internal opening securely.
Inject fat graft in small aliquots (≤1 mL) to prevent abscess formation.
Use appropriate fat processing method based on surgeon preference and fat availability.
Follow patients closely postoperatively for symptom improvement and fistula closure.
by Estella Y. Huang, Beiqun Zhao, Jason Llaneras, Shanglei Liu, Sarah B. Stringfield, Benjamin Abbadessa, Nicole E. Lopez, Sonia L. Ramamoorthy, Lisa A. Parry, Amanda A. Gosman, Marek Dobke, Samuel Eisenstein
