An unusual case of Staphylococcus pasteuri osteomyelitis

Staphylococcus pasteuri is a gram-positive organism found in food products as well as naturally occurring in air and on surfaces. We present the first known case of Staphylococcus pasteuri osteomyelitis caused by machine injection injury. The patient was treated with emergent surgical debridement as well as doxycycline for a soft tissue infection. Despite targeted therapy, the infection progressed to osteomyelitis and was treated successfully with additional surgical debridement and trimethoprim-sulfamethoxazole. There is sparse information on both infections and treatment of Staphylococcus pasteuri. We present our case report as well as a review of the literature on the epidemiology, susceptibility and treatment recommendations for Staphylococcus pasteuri infections.

Staphylococcus pasteuri infective endocarditis: A case report

Staphylococcus pasteuri is a coagulase negative bacterium which although formally described in 1993, has only recently become possible to reliably speciate in diagnostic microbiology laboratories. S. pasteuri remains an extremely infrequent cause of human infection to date, namely bacteremia in an individual suffering acute myeloid leukemia, catheter-associated urinary tract infection in a patient receiving chemotherapy and endocarditis within a case series without specific clinical information. As such, our report provides the first detailed account of Staphylococcus pasteuri infective endocarditis entailing a subacute community-onset infection involving native aortic and mitral valves, multiple systemic emboli, and ultimately cardiothoracic surgery.

Purification and Characterization of Pasteuricin Produced by Staphylococcus pasteuri RSP-1 and Active against Multidrug-Resistant Staphylococcus aureus

Staphylococcus aureus is an important pathogen implicated in various diseases, including staphylococcal food poisoning. Bacteriocins are considered safe and effective antimicrobial substances for the prevention of the growth of pathogenic bacteria. In this article, we describe the purification and characterization of pasteuricin, a novel bacteriocin produced by Staphylococcus pasteuri RSP-1. A cell-free supernatant of S. pasteuri RSP-1 exerted strong antimicrobial activity against staphylococci, including methicillin-resistant S. aureus (MRSA), and gram-positive bacteria. The loss of antimicrobial activity upon treatment with proteolytic enzymes confirmed the proteinaceous nature of pasteuricin. A rapid and pronounced bactericidal effect of pasteuricin was confirmed by a live-dead bacterial viability assay. To our knowledge, pasteuricin is the first reported S. pasteuri bacteriocin that inhibits S. aureus. Because pasteuricin is characterized by strong antimicrobial activity and high stability, it has potential as an alternative antimicrobial agent to antibiotics.

Distribution, origin and contamination risk of coagulase-negative staphylococci from platelet concentrates

Transfusion-associated bacterial sepsis is the most common microbiological risk of transfusion and is caused mostly by platelet concentrates (PCs). The most frequently identified bacterial contaminants of PCs are coagulase-negative staphylococci (CNS). In order to learn more about the distribution, source and risk of the CNS that are involved in bacterial contamination of PCs, CNS strains isolated during platelet screening were collected and characterized to the species level with three different methods: 16S rRNA and sodA gene sequencing, matrix-assisted laser desorption ionization-time of flight mass spectrometry (MALDI-TOF MS) and amplified fragment length polymorphism (AFLP) analysis. AFLP analysis was also used for the typing of the CNS strains. A total of 83 CNS strains were analysed by sequencing and 8 different CNS species were identified, with Staphylococcus epidermidis being the predominant species. MALDI-TOF MS and AFLP analysis confirmed these results to a large extent. However, MALDI_TOF MS could not identify all strains to the species level and AFLP analysis revealed an additional, likely novel, CNS species. The species identified are mainly recognized as being part of the normal skin flora. Typing of the CNS strains by AFLP analysis showed that there was not a unique strain which is significantly more often present during bacterial contamination of PCs.

Diversity of staphylococcal cassette chromosome mec structures in coagulase-negative staphylococci and relationship to drug resistance

The objective of this study was to determine the distribution of staphylococcal cassette chromosome mec (SCCmec) elements in meticillin-resistant coagulase-negative staphylococci (MR-CoNS) isolated from a tertiary-care hospital in Mexico and to examine the relationship to drug resistance. Fifty selected MR-CoNS isolates collected from catheters (n=15), blood (n=15), bone (n=9), bronchial lavage (n=2) and urine (n=2) and one isolate each from an abscess, cerebrospinal fluid, eye, pleural effusion, synovial fluid, tracheal aspirate and wound secretion were examined. Susceptibility testing was performed by the broth microdilution method. SCCmec types were determined by multiplex PCR and PFGE was carried out as described previously for Staphylococcus aureus. Among the MR-CoNS strains studied, the most frequently isolated species were Staphylococcus epidermidis (n=26) and Staphylococcus haemolyticus (n=13). Staphylococcus cohnii (n=5), Staphylococcus hominis (n=3), Staphylococcus sciuri (n=1), Staphylococcus pasteuri (n=1) and the recently described species Staphylococcus pettenkoferi (n=1) were also identified. The most frequent MR-CoNS genotype identified was SCCmec type IVa in S. epidermidis isolates, which also showed a high diversity in their PFGE patterns. A clone was found that amplified both SCCmec III and V elements in five isolates examined. The single MR S. pettenkoferi isolate harboured SCCmec type IVd and the single MR S. pasteuri isolate harboured SCCmec type I. The carriage of SCCmec type III was associated with resistance or intermediate resistance to meropenem (P <0.05). These results confirm the high prevalence of S. epidermidis SCCmec IVa and the high genetic diversity among MR-CoNS strains. As far as is known, this is the first report describing the newly identified S. pettenkoferi possessing SCCmec IVd and S. pasteuri harbouring SCCmec type I. MR-CoNS harbouring SCCmec type III were found to be more resistant to meropenem.