Studio di coorte sull’incidenza dei decubiti al calcagno in pazienti immobilizzati da gesso agli arti inferiori presso l’Istituto Ortopedico Rizzoli e dei possibili fattori di rischio

Introduzione. La lesione da decubito, in particolare al calcagno, può rappresentare una complicanza da immobilizzazione per apparecchio gessato. Obiettivo. Indagare l’incidenza delle complicanze cutanee tardive (in particolare la lesione da decubito al calcagno) da apparecchio gessato e valutare eventuali fattori di rischio. Materiali e metodi. Sono stati monitorati per 16 mesi tutti i pazienti consecutivi, provenienti da tre reparti, a cui veniva applicato un apparecchio gessato agli arti inferiori. I fattori di rischio sono stati identificati dall’infermiere addetto al confezionamento del gesso e la gravità della lesione stadiata con la scala NPUAP, al momento dell’asportazione del gesso, dall’infermiere del reparto o dell’ambulatorio. Risultati. Sono stati arruolati 216 pazienti. Il 17.6% (38/216) ha avuto una lesione da decubito: 16/124 (13%) nei reparti ortopedici e 22/92 (24%) nei reparti oncologici. Sono risultati fattori di rischio all’analisi multivariata, l’essere sottoposti a trattamenti con farmaci antiblastici (p=0.033; OR=2.61) (la sola patologia oncologica non aumentava il rischio rispetto alla popolazione ortopedica generale); l’avere la cute arrossata prima dell’applicazione dell’apparecchio gessato (p=0.001; OR=4.44) e l’avere accusato disturbi dopo l’applicazione (p=0.000; OR=7.86). Le lesioni erano prevalentemente di 1° grado e solo il 2.4% (6/216) erano di II grado o superiore. L’estensione e la durata del gesso, il materiale con cui viene confezionato, e l’aver subito un intervento chirurgico non sono risultati fattori di rischio statisticamente significativi. Conclusioni. Le lesioni da decubito da gesso sono una complicanza relativamente frequente in particolare in alcune popolazioni a rischio che devono tenere immobilizzati gli arti inferiori. La conoscenza del rischio di base e l’identificazione di specifici fattori di rischio possono permettere l’identificazione e lo studio di misure preventive per migliorare l’assistenza a questa specifica popolazione

Biofilm extracellular-DNA in 55 Staphylococcus epidermidis clinical isolates from implant infections

Biofilm formation is broadly recognized as an important virulence factor in many bacterial species implicated in implant-related opportunistic infections. In spite of a long history of research and many investigative efforts aimed at elucidating their chemical composition, structure, and function, the nature of bacterial biofilms still remains only partly revealed. Over the years, different extracellular polymeric substances (EPS) have been described that contribute functionally and structurally to the organization of biofilms. Recently extracellular DNA (eDNA) has emerged as a quantitatively conspicuous and potentially relevant structural component of microbial biofilms of many microbial species, Staphylococcus aureus and S. epidermidis among them. The present study aims at comparatively investigating the amount of eDNA present in the biofilm of 55 clinical isolates of S. epidermidis from postsurgical and biomaterial-related orthopedic infections. Quantification of eDNA was performed by a non-destructive method directly on bacterial biofilms formed under static conditions on the plastic surface of 96-well plates

Characterization of 26 Staphylococcus warneri isolates from orthopedic infections

Staphylococcus warneri is a coagulase negative Staphylococcus (CNS) commonly present in the flora of human epithelia and mucosal membranes. Over the last two decades, similarly to other CNS species, S. warneri has been reported as a new emerging pathogen, capable of causing serious infections usually in association with the presence of implant materials, but, at times, even in the absence of a foreign body and in patients considered immunocompetent. At present, there is still a lack of scientific data on the pathogenesis and epidemiology of this species. The present study investigated a collection of 26 clinical isolates derived from orthopedic infections, some associated with implant materials and others not. Automated ribotyping showed the existence of 5 distinct ribogroups. Except for the least numerous ribogroup consisting of a single isolate, all other ribogroups included at least one strain obtained from an infection not associated with implant materials, suggesting that putative virulence factors necessary for infections even in the absence of a foreign body could be transversal to most ribogroup categories. Orthopedic infections were found to involve S. warneri strains with low antibiotic resistance potential, differing in this respect from the strains isolated at neonatal intensive care units, where this species has been described to figure among the principal causative agents and exhibit an alarming profile of antibiotic resistance

Characterization of 26 Staphylococcus warneri isolates from orthopedic infections

Staphylococcus warneri is a coagulase negative Staphylococcus (CNS) commonly present in the flora of human epithelia and mucosal membranes. Over the last two decades, similarly to other CNS species, S. warneri has been reported as a new emerging pathogen, capable of causing serious infections usually in association with the presence of implant materials, but, at times, even in the absence of a foreign body and in patients considered immunocompetent. At present, there is still a lack of scientific data on the pathogenesis and epidemiology of this species. The present study investigated a collection of 26 clinical isolates derived from orthopedic infections, some associated with implant materials and others not. Automated ribotyping showed the existence of 5 distinct ribogroups. Except for the least numerous ribogroup consisting of a single isolate, all other ribogroups included at least one strain obtained from an infection not associated with implant materials, suggesting that putative virulence factors necessary for infections even in the absence of a foreign body could be transversal to most ribogroup categories. Orthopedic infections were found to involve S. warneri strains with low antibiotic resistance potential, differing in this respect from the strains isolated at neonatal intensive care units, where this species has been described to figure among the principal causative agents and exhibit an alarming profile of antibiotic resistance