AIM: To investigate the resistance to bacterial adhesion of materials used in oculoplastic surgery, particularly materials used in the manufacture of orbital implants.METHODS: Seven organisms of conjunctival flora(two...AIM: To investigate the resistance to bacterial adhesion of materials used in oculoplastic surgery, particularly materials used in the manufacture of orbital implants.METHODS: Seven organisms of conjunctival flora(two strains of Staphylococcus epidermidis and one strain each of Staphylococcus aureus, Staphylococcus hominis, Corynebacterium amycolatum, Acinetobacter calcoaceticus, and Serratia marcescens) were selected. A lactic acid bacterium(Lactobacillus rhamnosus) was also included as positive control because of its well-known adhesion ability. Eight materials used to make oculoplastic prostheses were selected(glass, steel, polytetrafluoroethylene, polymethylmethacrylate, silicone from orbital implants, commercial silicone, porous polyethylene, and semismooth polyethylene). Materials surfaces and biofilms developed by strains were observed by scanning electron microscopy. Kinetics of growth and adhesion of bacterial strains were determined by spectrophotometry. Each strain was incubated in contact with plates of the different materials. After growth, attached bacteria were re-suspended and colony-forming units(CFUs) were counted. The number of CFUs per square millimetre of material was statistically analyzed.RESULTS: A mature biofilm was observed in studied strains except Staphylococcus hominis, which simply produced a microcolony. Materials showed a smooth surface on the microbial scale, although steel exhibited 1.0-μm-diameter grooves. Most organisms showed significant differences in adhesion according to the material. There were also significant differences in thetotal number of CFUs per square millimetre from each material(P=0.044). CFU counts were significantly higher in porous polyethylene than in silicone from orbital implants(P=0.038).CONCLUSION: Silicone orbital implants can resist microbial colonization better than porous polyethylene implants.展开更多
AIM: To identify the spectrum and susceptibility pattern of isolated microorganisms from conjunctival flora of anophthalmic patients.METHODS: A cross-sectional clinical study including 60 patients with unilateral anop...AIM: To identify the spectrum and susceptibility pattern of isolated microorganisms from conjunctival flora of anophthalmic patients.METHODS: A cross-sectional clinical study including 60 patients with unilateral anophthalmia. Patients with use of antibiotic drops in their socket during the last month were also included. From each patient, three microbiological samples were taken from the lower conjunctival sac(healthy eye, pre-prosthesis, and retro-prosthesis space of socket). The 180 samples obtained were cultured. Isolates were identified and their antibiotic sensitivities were determined.RESULTS: A total of 251 isolates were recovered(62 isolates from healthy eye, 93 from pre-prosthesis, and 96 from retro-prosthesis space). The most common organism was Staphylococcus epidermidis, in both healthy eyes(64.5%) and sockets(45.5%). Altogether, coagulasepositive Staphylococci, Streptococci, and Gram-negative bacteria accounted for less than 15% of isolates in healthy eyes and more than 35% in sockets. Regarding the antibiotic sensitivities, there were no significant differences between isolates from sockets and healthy eyes. Nine patients recognized the use of self-prescribed antibiotic drops in their socket. In the healthy eyes of these subjects, Gram-positive microorganisms showed significantly greater resistance to aminoglycosides and tetracycline.CONCLUSION: Sockets of anophthalmic patients show a greater number of pathogens compared to healthy eyes.The use of antibiotic drops in the socket promotes a resistant flora not only in the socket but also in the healthy eye. Quinolones and macrolides may be better therapeutic options than aminoglycosides for treating conjunctivitis of anophthalmic sockets, since these antibiotics are less active against Staphylococcus epidermidis.展开更多
基金Supported by the Dirección General de Investigación(SAF 2015-64306-R)the Junta de Castilla y León,Spain(LE283U14)
文摘AIM: To investigate the resistance to bacterial adhesion of materials used in oculoplastic surgery, particularly materials used in the manufacture of orbital implants.METHODS: Seven organisms of conjunctival flora(two strains of Staphylococcus epidermidis and one strain each of Staphylococcus aureus, Staphylococcus hominis, Corynebacterium amycolatum, Acinetobacter calcoaceticus, and Serratia marcescens) were selected. A lactic acid bacterium(Lactobacillus rhamnosus) was also included as positive control because of its well-known adhesion ability. Eight materials used to make oculoplastic prostheses were selected(glass, steel, polytetrafluoroethylene, polymethylmethacrylate, silicone from orbital implants, commercial silicone, porous polyethylene, and semismooth polyethylene). Materials surfaces and biofilms developed by strains were observed by scanning electron microscopy. Kinetics of growth and adhesion of bacterial strains were determined by spectrophotometry. Each strain was incubated in contact with plates of the different materials. After growth, attached bacteria were re-suspended and colony-forming units(CFUs) were counted. The number of CFUs per square millimetre of material was statistically analyzed.RESULTS: A mature biofilm was observed in studied strains except Staphylococcus hominis, which simply produced a microcolony. Materials showed a smooth surface on the microbial scale, although steel exhibited 1.0-μm-diameter grooves. Most organisms showed significant differences in adhesion according to the material. There were also significant differences in thetotal number of CFUs per square millimetre from each material(P=0.044). CFU counts were significantly higher in porous polyethylene than in silicone from orbital implants(P=0.038).CONCLUSION: Silicone orbital implants can resist microbial colonization better than porous polyethylene implants.
基金Supported by The Dirección General de Investigación (No.SAF 2015-64306-R)The Junta de Castilla y León, Spain (No.LE283U14)
文摘AIM: To identify the spectrum and susceptibility pattern of isolated microorganisms from conjunctival flora of anophthalmic patients.METHODS: A cross-sectional clinical study including 60 patients with unilateral anophthalmia. Patients with use of antibiotic drops in their socket during the last month were also included. From each patient, three microbiological samples were taken from the lower conjunctival sac(healthy eye, pre-prosthesis, and retro-prosthesis space of socket). The 180 samples obtained were cultured. Isolates were identified and their antibiotic sensitivities were determined.RESULTS: A total of 251 isolates were recovered(62 isolates from healthy eye, 93 from pre-prosthesis, and 96 from retro-prosthesis space). The most common organism was Staphylococcus epidermidis, in both healthy eyes(64.5%) and sockets(45.5%). Altogether, coagulasepositive Staphylococci, Streptococci, and Gram-negative bacteria accounted for less than 15% of isolates in healthy eyes and more than 35% in sockets. Regarding the antibiotic sensitivities, there were no significant differences between isolates from sockets and healthy eyes. Nine patients recognized the use of self-prescribed antibiotic drops in their socket. In the healthy eyes of these subjects, Gram-positive microorganisms showed significantly greater resistance to aminoglycosides and tetracycline.CONCLUSION: Sockets of anophthalmic patients show a greater number of pathogens compared to healthy eyes.The use of antibiotic drops in the socket promotes a resistant flora not only in the socket but also in the healthy eye. Quinolones and macrolides may be better therapeutic options than aminoglycosides for treating conjunctivitis of anophthalmic sockets, since these antibiotics are less active against Staphylococcus epidermidis.
