Phenotypic and genomic identification of Staphylococcus epidermidis GOI1153754-03-14 isolated from an infected orthopedic prosthesis

Introduction: Staphylococcus epidermidis GOI1153754-03-14 is able to colonize orthopedic implants and to cause septic non-unions, as validated in a recent in vivo study (Lovati, 2016). To pore over the mechanisms leading to the biofilm formation on metallic implants, in the present study, we carried out the phenotypic and genotypic characterization of the clinical isolate S. epidermidis GOI1153754-03-14.Materials and Methods: The antimicrobial susceptibility and minimum inhibitory concentration (MIC) of the strain were evaluated through the Vitek2 System (Biomerieux), as well as its ability to form biofilm in vitro through a spectrophotometric assay (Stepanovich, 2000).The genomic DNA was extracted by Bacterial Genomic DNA Isolation Kit (Norgen Biotek Corp.). Libraries were prepared with the ThruPLEX DNA-seq (Rubicon Genomics) and then sequenced on the Illumina MiSeq platform through the MiSeq Reagent Kit v3 (600-cycles) to produce 300 bp paired-end reads (Illumina Inc.). Reads were quality-trimmed and gene annotated thanks to the RAST software (Aziz, 2008).Results: The antimicrobial susceptibility along with the MIC values are reported in Table 1. The outputs resulted in 51 contigs (Average = 50,720.6 Mb) with 396X fold average coverage. The total genome is 2,586,753 bp long with a GC content of 31.84% and an N50 value of 7 bp. The whole genome is composed by 2,467 protein-encoding genes and 64 RNAs (55 tRNAs and 9 rRNAs). The entire genome sequence has been deposited in the European Nucleotide Archive (ENA) under the accession no. FWCG01000000 (Bottagisio, 2017).Discussion: The genotypic and phenotypic characterization of the S. epidermidis GOI1153754-03-14 will enable a better comprehension of the mechanisms involved in the biofilm formation on orthopedic implants paving the way for innovative preventative and therapeutic strategies. Moreover, the sequence of this clinical strain is mandatory to develop dedicated proteomics analysis in order to highlight functional mechanism of biofilm formation

Antibacterial Bioactive Glass, S53P4, for Chronic Bone Infections - A Multinational Study

Correction: Volume: 971 Pages: 115-116 DOI: 10.1007/5584_2017_13 Published: 2017 WOS:000446017300010Osteomyelitis is an infectious process in bone that occasionally leads to bone destruction. Traditionally, the surgical treatment procedure is performed in combination with systemic and local antibiotics as a two-stage procedure that uses autograft or allograft bone for filling of the cavitary defect. Bioactive glass (BAG-S53P4) is a bone substitute with proven antibacterial and bone bonding properties. One hundred and sixteen patients who had verified chronic osteomyelitis was treated using BAG-S53P4 as part of the treatment. Most of the patients had previously undergone numerous procedures, sometimes for decades. A register of patient data obtained from 11 centers from Finland, Italy, the Netherlands, Germany, Azerbaijan and Poland was set-up and continuously maintained at Helsinki University Central Hospital. The location of the osteomyelitis was mainly in the tibia followed by the femur and then the calcaneus. The median age of the patients was 48 years (15-87). The patients were either treated according to a one-stage procedure without local antibiotics (85 %) or by a two-stage procedure using antibiotic beads in the first procedure (15 %). The minimum follow-up was 1 year (12-95 months, median 31). The cure rate was 104/116, the total success rate 90 % and most of the patients showed a rapid recovery. The study shows that (BAG-S53P4) can be used in a one-stage procedure in treatment of osteomyelitis with excellent results.Peer reviewe

Prevenzione delle infezioni peri-protesiche mediante rivestimento riassorbibile anti-batterico: un nuovo approccio?

Currently studied antibacterial coatings are far from having large-scale applications, due to various limitations. A recently developed fast resorbable, antibacterial-loaded, hydrogel coating may provide a new approach to offer an effective antibacterial and antibiofilm protection to orthopedic implants

Successful staged hip replacement in septic hip osteoarthritis in osteopetrosis: a case report

<p>Abstract</p> <p>Background</p> <p>Osteopetrosis is a rare, inherited, bone disorder, characterized by osteosclerosis, obliteration of the medullary cavity and calcified cartilage. The autosomal dominant form is compatible with a normal life span, although fractures often result from minimal trauma, due to the pathologic nature of bone. Osteomyelitis is common in patients with osteopetrosis because of a reduced resistance to infection, attributed to the lack of marrow vascularity and impairment of white cell function. Only one case of osteomyelitis of the proximal third of the femur has been previously reported, treated with several repeated debridements and finally with femoral head resection. Here we present for the first time a case of a staged implant of a cementless total hip prosthesis for the treatment of a septic hip in femoral neck nonunion in osteopetrosis.</p> <p>Case presentation</p> <p>A 36-years-old woman, affected by autosomal dominant osteopetrosis was referred to our department because of a septic hip arthritis associated with femoral neck septic non-union, with draining fistulas. The infection occurred early after a plate osteosynthesis for a closed perthrocanteric fracture of the femur and persisted in spite of osteosynthesis removal, surgical debridement and external fixation. In our hospital the patient underwent accurate debridement, femoral head and greater trochanter resection, preparation of the diaphyseal intramedullary canal and implant of an antibiotic-loaded cement spacer. The spacer was exchanged after one month, due to infection recurrence and four months later, a cementless total hip arthroplasty was implanted, with no clinical and laboratory signs of infection recurrence at two years follow-up.</p> <p>Conclusions</p> <p>In case of hip septic arthritis and proximal femur septic non-union, femoral head resection may not be the only option available and staged total hip arthroplasty can be considered.</p