Background and Importance In the intensive care unit, wound infections are complications with highly associated morbimortality, especially in immunocompromised patients. In some circumstances, a combination of endovenous and topical therapies may be required. Due to the lack of adequate commercial presentations, a compounded topical treatment could be a solution to manage a specific infection.

Aim and Objectives Developing a sterile topical gel of Amphotericin B-deoxycholate (Amfob-dc) and colistin to treat severe necrotic wound caused by Aspergillus fumigatu, Acinetobacter baumanii and Rhizopus arizus refractory to surgical debridement in a critical patient. Galenic and microbiological validation.

Material and Methods Bibliographic research was done first and based on the information compiled, it was decided to use sterile water-soluble gel(Varihesive Hydrogel®) as an excipient base. Varihesive Hydrogel is used on the debridement of necrotic wounds. When used with AmfoB-dc 0,15% and colisitin 0,5% in sterile conditions, both refrigerated, remained 7-days stable based on the risk matrix (low risk) of Good Pharmacy Practices. For galenic and microbiological validation, 3 samples of both gels were stored in refrigerator and in room temperature protected from light. Organoleptic characteristics (colour and fluidity), pH and weight were controlled and validated at days 0,7,14,21 and 28 of preparation. Microbiological validation was performed at day 28. Efficacy of treatment was studied with wound reduction and granulation one month after the initiation of the treatment, which was applied 3 tid.

Results Particle-free, homogeneous and viscous gels were obtained. The AmfoB-dc gel exhibited yellow colour and the colistin-based gel gray-translucent. No microbial growth was observed between days 0 to 28. Organoleptic characteristics remained constant throughout the period, however, once stored at cold tempatures they exhibited more viscosity.There were no differences in pH levels or weight variation of >10% (table 1).

Clinical Outcomes were excellent one month after the initiation resulting in an 80% reduction and granulation of the wounds and negative microbiological cultures.

Conclusion and Relevance These formulations are simple and give accurate results as a targeted therapy for necrotising infected wounds. The individualised topical preparations allow to solve problems of unavailability of adequate commercial forms. According to our validation, the galenic stability of the product seemed to be extended. However, further stability and quantitative studies should be conducted.

Conflict of Interest No conflict of interest