SLR - June 2018 - Cathy T. Chuang

A Comparative Analysis of the Efficacy of Topical Phenytoin with Conventional Wound Dressing in Healing of Diabetic Foot Ulcers

Reference: Prasad S, Prakash A, Patel S, Lunawat A, Mahore D. A Comparative Analysis of the Efficacy of Topical Phenytoin with Conventional Wound Dressing in Healing of Diabetic Foot Ulcers. Int Surg J 2017;4:1389–93.

Scientific Literature Review

Reviewed By: Cathy T. Chuang, DPM
Residency Program: Chino Valley Medical Center, Chino, CA

Podiatric Relevance: Diabetic complications are a serious public health issue. The prevalence of diabetic foot ulcers globally is 6.3 percent, with North America being the most severely affected region at 13.0 percent. According to the American Diabetes Association, nearly 100,000 lower-limb amputations are performed annually on patients living with diabetes in the United States alone. The authors conducted a study to compare the efficacy of topical phenytoin with conventional wound dressings in healing of diabetic foot ulcers.

Methods: A prospective randomized study was undertaken at a tertiary healthcare center. Fifty patients were included in the study and randomly divided into a betadine group and a phenytoin group by using a lottery system. Inclusion criteria included Wagner grade 1 and 2 diabetic foot ulcers and patients with controlled diabetes. Exclusion criteria included Wagner grade 3 to 5 ulcers, chronic ulcer of other etiology and any other comorbidity, such as renal failure, generalized debility and patients with phenytoin allergy. In each patient, one ulcer was chosen, surgically debrided and measured. A single 100 mg phenytoin sodium capsule was opened and suspended in 5 mL of sterile normal saline. The betadine group consisted of 5 percent povidone-iodine solution. Dressing changes were done twice daily. Patients were followed up daily for 14 days with wound culture obtained at seventh and 14th day. Patients were then subjected to a split thickness skin graft. In each patient, the rate of granulation tissue formation, graft uptake measured at fifth postop day, duration of the hospital stay and culture sensitivity were statistically calculated and compared. One-month follow-up was also done for postsurgical complications. The means were compared using paired and unpaired student’s t-test, and comparison was performed using chi-square test with p-value of < 0.05 as significant.

Results: The rate of granulation tissue formation was significantly higher for the phenytoin group (42.50 +/- 4.48 percent at day 14) versus betadine group (36.68 +/- 5.89 percent at day 14). The graft uptake in the phenytoin group (40.57 +/- 5.14 percent) was also significantly higher compared to the betadine group (34.41 +/- 5.27 percent). The mean hospital stay was shorter for the phenytoin group (17.64 days versus 20.04 days); however, it was not statistically significant. Negative wound culture after 14 days of treatment was significantly higher in the phenytoin group (96 percent) versus betadine group (52 percent). One month follow-up did not show an increase in common side effects from long-term use of phenytoin, such as hypersensitivity reactions like fever, rash and lymphadenopathy.

Conclusions: Topical phenytoin dressing decreases bacterial load and forms healthy granulation tissue for graft preparation. The overall hospital stay and postoperative complications were also less compare to the conventional group. Thus, topical phenytoin could be an effective therapeutic agent in treating diabetic foot ulcers compared to a conventional treatment modality, such as using betadine dressings.

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