Prophylactic antibiotics in plastic and reconstructive surgery.

There is no consensus in the literature on the use of prophylactic antibiotics to prevent postoperative infection. This study was performed to investigate whether the use of prophylactic antibiotics has an effect on postoperative infection rates. A total of 1400 patients were classified into four groups based on their diagnosis. During the induction of anesthesia, half of each group received 2 g of a sulbactam-ampicillin combination and the other half received a placebo (saline solution) intravenously. Wound infection rates were observed in the postoperative period. Age, sex, and operative site of the patients with the same diagnosis were comparable in each group. The white blood cell count and the body temperature reading of each patient were recorded postoperatively. Wounds were observed daily in the postoperative period and graded according to a predetermined scale. Bacteriologic specimens were obtained from patients who had wound infections. According to our clinical experience, antibiotic prophylaxis is not necessary in plastic surgery. At the end of our 6-year study, a significant difference could not be found between the antibiotic prophylaxis and placebo groups.     

Treatment of massive thoracolumbar wounds and vertebral osteomyelitis following scoliosis surgery

Closure of thoracolumbar wounds and vertebral osteomyelitis after scoliosis surgery often proves difficult due to tautness and lack of usable tissue, and the resulting dead space containing metallic fixation devices is predisposed to infections and complications. The authors present their experience with 33 patients in whom massive thoracolumbar wounds and vertebral osteomyelitis developed following scoliosis surgery. Postoperative infection, due to the lack of vascularized tissue and presence of metallic hardware near the wound, is common and extremely counterproductive; within these cavernous wounds lie infected vertebrae, metallic hardware, and bone graft. The use of a modified and extended latissimus dorsi myocutaneous flap to close and supply blood to wounds in the lower thoracic and thoracolumbar areas is described. This surgical approach, predicated on effective débridement along with reconstruction by transposition of vascularized tissue, allows the wound to close and drastically decreases the risk of postoperative infection. Furthermore, for wounds already infected, the procedure allows for closure and increased blood supply to the area, thus giving the wound a much greater ability to heal. For wounds involving the lumbosacral area, the authors combine this with a transposed gluteus maximus muscle flap to obtain coverage over the caudal extent of the wound. In this study, all flaps accomplished their intended purpose: to secure the healing of once-infected wounds and to allow preservation of orthopedic instrumentation and bone graft. Follow-up revealed no flap losses, pseudarthroses, or loss of orthopedic instrumentation in the study group.     

鼻内镜手术合并大环内酯类抗生素治疗鼻窦炎43例

目的:评价鼻内镜手术治疗合并术后利用大环内酯类抗生素治疗鼻窦炎的疗效,探讨鼻窦炎患者治疗前后血清中IL-17及其受体的表达及血清中总IgE的变化。方法:鼻窦内窥镜行病侧上颌寞自然口扩大及下鼻道开窗双进路,彻底清除鼻腔、鼻窦病变组织,术后采用大环内酯类抗生素治疗;采用酶联免疫法检测30例患者治疗前后血清中IL-17,IL-17R及IgE的含量。结果:治疗30例,其中术后病理证实鼻寞真菌球20例,治愈20例;曲霉菌感染23例,治愈10例,6个月随访无复发;与只治疗前相比,手术治疗后鼻窦炎患者血清IL-17,IL-17R及IgE的含量均明显降低。结论:鼻内镜手术是治疗真菌性鼻一鼻窦炎的主要方法,IL-17和IL-17R均参与鼻窦炎的发病过程,可作为诊断鼻窦炎的新指标,鼻内镜术后使用大环内酯类抗生素进一步巩固治疗,可降低复发率。     

A meta-analysis of prophylactic antibiotics in head and neck surgery.

Although it is generally agreed that prophylactic antibiotics are necessary for the prevention of postoperative wound infection, the choice of antibiotic regimen is controversial. In an attempt to determine the most effective antibiotic regimen, a meta-analysis of published clinical trials of prophylactic antibiotics for head and neck surgery was undertaken. The meta-analysis revealed a relative difference in infection rates of 43.7 percent in favor of the use of antibiotics versus placebo, of 8.3 percent in favor of multiple antibiotics versus a single antibiotic, of 13.7 percent in favor of multiple antibiotics versus cefazolin, and of 4.1 percent in favor of multiple-day prophylaxis versus single-day prophylaxis. This meta-analysis suggests that a 1-day course of clindamycin may be the most effective prophylactic antibiotic regimen for head and neck surgery.     

Sensitivity to cephalosporin antibiotics of infectious causative agents in surgery

Comparison of antimicrobial effects of cephalosporins of the 1st and 2nd generations showed that the latter were advantageous with respect to gram-negative bacteria causing surgical infections. Three cephalosporins of the 3rd generation were characterized by the highest activity against such bacteria, including Enterobacter spp. and indole positive strains of Proteus spp., as well as non-enzymatic bacteria. The antimicrobial spectra and MICs of the new cephalosporins with respect to the cultures isolated from surgical patients were different which requires in vitro sensitivity assay of each antibiotic.     

Sideromycins: tools and antibiotics

Sideromycins are antibiotics covalently linked to siderophores. They are actively transported into gram-positive and gram-negative bacteria. Energy-coupled transport across the outer membrane and the cytoplasmic membrane strongly increases their antibiotic efficiency; their minimal inhibitory concentration is at least 100-fold lower than that of antibiotics that enter cells by diffusion. This is particularly relevant for gram-negative bacteria because the outer membrane, which usually forms a permeability barrier, in this case actively contributes to the uptake of sideromycins. Sideromycin-resistant mutants can be used to identify siderophore transport systems since the mutations are usually in transport genes. Two sideromycins, albomycin and salmycin, are discussed here. Albomycin, a derivative of ferrichrome with a bound thioribosyl-pyrimidine moiety, inhibts seryl-t-RNA synthetase. Salmycin, a ferrioxamine derivative with a bound aminodisaccharide, presumably inhibts protein synthesis. Crystal structures of albomycin bound to the outer membrane transporter FhuA and the periplasmic binding protein FhuD have been determined. Albomycin and salmycin have been used to characterize the transport systems of Escherichia coli and Streptococcus pneumoniae and of Staphylococcus aureus, respectively. The in vivo efficacy of albomycin and salmycin has been examined in a mouse model using Yersinia enterocolitica, S. pneumoniae, and S. aureus infections. Albomycin is effective in clearing infections, whereas salmycin is too unstable to lead to a large reduction in bacterial numbers. The recovery rate of albomycin-resistant mutants is lower than that of the wild-type, which suggests a reduced fitness of the mutants. Albomycin could be a useful antibiotic provided sufficient quantities can be isolated from streptomycetes or synthesized chemically.     

Pyogenic vertebral osteomyelitis: diagnosis and management.

Vertebral osteomyelitis represents a diagnostic challenge to the clinician. Two cases of pyogenic vertebral osteomyelitis occurring weeks to months after a urinary tract infection with Escherichia coli are described. The rarity and subtle clinical presentation of this condition, the presence of pre-existing degenerative arthritic changes, and delayed appearance of radiologic signs of progression to destructive osteomyelitis contributed to a significant delay in diagnosis. Increased awareness of vertebral osteomyelitis as a clinical entity combined with information from radionuclide scanning may permit earlier detection of this condition.     

Haematogenous osteomyelitis and staphylococcus aureus

Some 80 – 90% of all acute haematogeneous osteomyelitis is caused by staphylococcus aureus. We suggest that this is due to the special ability of staphylococci to synthesise prostaglandins from appropriate precursors such as arachidonic acid. Prostaglandins, especially of the E series, are potent stimulators of bone resorption. Establishment of osteomyelitis could thus result from minor bone trauma and local release of prostaglandins and their precursors, followed by adventitious infection. Infection by staphylococcus aureus, but not by other bacteria, could then lead to a sudden surge in prostaglandin production and so bone destruction, facilitating the formation of an osteomyelitic focus.