ABSTRACT
BACKGROUND: Bacterial contamination remains the major problem in skin banks, even after antimicrobial treatment, and results in high rates of tissue discarding. This study aimed to analyze bacterial contamination in 32 human skin allografts from the skin bank of Dr. Roberto Corrêa Chem from the Hospital Complex Santa Casa de Misericórdia de Porto Alegre. These samples were already discarded due to microbial contamination. The identification of the bacteria isolated from skin allografts was performed by matrix assisted laser desorption ionization-time of flight. The antimicrobial susceptibility of the isolates to six different classes of antimicrobials was determined using the disk-diffusion agar method, and the evaluation of the inhibitory potential was determined by the minimal inhibitory concentration (50/90) of antimicrobials already used in the skin bank and those that most isolates were susceptible to. RESULTS: A total of 21 (65.6%) skin samples were contaminated with Gram-positive bacteria: 1 (4.7%) with Paenibacillus sp., 12 (61.9%) with Bacillus sp., 6 (28.5%) with Staphylococcus sp., and 2 (9.5%) with Bacillus sp. and Staphylococcus sp. Several resistance profiles, including multiresistance, were found among the isolates. Most of the isolates were susceptible to at least one of the antimicrobials used in the skin bank. All isolates were susceptible to amikacin, gentamicin, and tetracycline, which demonstrated the best inhibitory activities against the isolates and were considered as potential candidates for new antimicrobial treatments. CONCLUSIONS: Bacillus, Paenibacillus, and Staphylococcus were isolated from the skin allografts, thus demonstrating the predominance of Gram-positive bacteria contamination. Other factors not related to the resistance phenotype may also be involved in the persistence of bacterial isolates in the skin allografts after antibiotic treatment. Gentamicin, amikacin, and tetracycline can be considered as an option for a more effective treatment cocktail.
Subject(s)
Allografts/microbiology , Bacteria/isolation & purification , Skin/microbiology , Adolescent , Adult , Aged , Anti-Bacterial Agents/pharmacology , Bacteria/classification , Bacteria/genetics , Child , Drug Resistance, Bacterial , Female , Humans , Male , Middle Aged , Skin Transplantation , Tissue Banks/statistics & numerical data , Young AdultABSTRACT
OBJETIVO: Verificar se a talidomida é capaz de evitar a rejeição de aloenxertos de pele em coelhos, como droga isolada, ou melhorar a eficácia de doses subterapêuticas de ciclosporina, comparando seu efeito ao de doses terapêuticas da ciclosporina e também ao papel antiinflamatório do diclofenaco de sódio. MÉTODOS: Foram estudados 42 coelhos, distribuídos nos seguintes grupos (n=6): Grupo 1 - controle com auto-enxerto; Grupo 2 - controle com aloenxerto; Grupo 3 - aloenxerto sob o efeito de talidomida (100 mg/kg/dia); Grupo 4 - aloenxerto sob o efeito de diclofenaco de sódio (2 mg/kg/dia); Grupo 5 - aloenxerto sob o efeito de ciclosporina (10 mg/kg/dia); Grupo 6 - aloenxerto sob o efeito de ciclosporina (5 mg/kg/dia); Grupo 7 - aloenxerto sob o efeito de ciclosporina (5 mg/kg/dia) associada a talidomida (100 mg/kg/dia). Foram retirados enxertos circulares de pele total do dorso de uma das orelhas do animal. Os medicamentos foram administrados por cateter orogástrico, a partir do dia anterior ao transplante. Os enxertos foram trocados entre coelhos de raças diferentes. RESULTADOS: A ciclosporina a 10 mg/kg/dia prolongou a sobrevida dos enxertos de pele, sendo seu efeito comparável ao obtido com a ciclosporina em dose subterapêutica (5 mg/kg/dia) associada a talidomida a 100 mg/kg/dia. A talidomida isoladamente, mesmo em concentração de 100 mg/kg/dia, e o diclofenaco tiveram efeito mínimo na sobrevida média dos aloenxertos cutâneos. O número de eosinófilos no infiltrado inflamatório circunjacente à necrose foi maior nos grupos tratados com diclofenaco e com ciclosporina a 5 mg/kg/dia e menor no grupo em que se associou ciclosporina com talidomida. CONCLUSÃO: A talidomida pode ser uma droga útil para associar-se a baixas doses de ciclosporina no tratamento de aloenxertos cutâneos.
OBJECTIVE: Allografting is one of the therapeutic alternatives for extensive burn victims without sufficient skin donor areas. This research studied the effects of cyclosporine, as an immunosuppressor model, and thalidomide and dyclofenac as anti-inflammatory drugs on an experimental skin allograft research. METHODS: Forty-two rabbits were divided in the following groups (n=6): Group 1 - autografting control; Group 2 - allografting control; Group 3 - allografts under thalidomide effect (100 mg/kg/day); Group 4 - allografts under sodium dyclofenac effect (2 mg/kg/day); - Group 5 -allografts under cyclosporine effect (10 mg/kg/day); Group 6 - allografts under cyclosporine effect (5 mg/kg/day); Group 7- allografts under cyclosporine (5 mg/kg/day) plus thalidomide (100 mg/kg/day) effect. Drugs were given via orogastric tube since the day before transplantation and daily during the postoperative period. Circular total skin grafts of the ear were exchanged between California and White New Zealand rabbits. RESULTS: Cyclosporine 10 mg/kg/day increased allograft survival and this effect was comparable to the association of cyclosporine 5 mg/kg/day with thalidomide 100 mg/kg/day. Thalidomide as an isolated drug and dyclofenac had a minimum effect on the average survival of the skin allografts. The number of eosinophils around the necrotic skin was higher in the dyclofenac group and lower in the group receiving cyclosporine associated with thalidomide. CONCLUSION: This study showed that thalidomide may be an useful drug when associated with subtherapeutic doses of cyclosporine for treatment of skin allografts.