Hilary Humphreys

Learn More
Device-associated infections involving biofilm remain a persistent clinical problem. We recently reported that four methicillin-resistant Staphylococcus aureus (MRSA) strains formed biofilm independently of the icaADBC-encoded exopolysaccharide. Here, we report that MRSA biofilm development was promoted under mildly acidic growth conditions triggered by the(More)
Production of icaADBC-encoded polysaccharide intercellular adhesin, or poly-N-acetylglucosamine (PIA/PNAG), represents an important biofilm mechanism in staphylococci. We previously described a glucose-induced, ica-independent biofilm mechanism in four methicillin-resistant Staphylococcus aureus (MRSA) isolates. Here, biofilm regulation by NaCl and glucose(More)
Meticillin-resistant Staphylococcus aureus (MRSA) remains endemic in many UK hospitals. Specific guidelines for control and prevention are justified because MRSA causes serious illness and results in significant additional healthcare costs. Guidelines were drafted by a multi-disciplinary group and these have been finalised following extensive consultation.(More)
OBJECTIVES To review and document the changing patterns in diagnosis, causes and treatment of bacterial infections of the central nervous system (CNS) in a national neurosurgical unit only in patients from whom a specimen was obtained for culture. METHODS The case notes, radiological results and laboratory records of all 163 patients in our institution(More)
Nosocomial infection is a major problem in intensive therapy units (ITUs) and a significant cause of mortality. Selective decontamination of the digestive tract (SDD) has been advocated as a means to reduce ITU morbidity and mortality. Ninety-one patients in a general ITU underwent SDD, consisting of topical polymyxin E, tobramycin and amphotericin B(More)
Prosthetic aortic graft infections represent a major diagnostic and therapeutic challenge. Although a combination of clinical assessment, imaging and microbiological investigations is usually helpful, there are no agreed criteria to confirm a diagnosis. Potential pathogens isolated from superficial specimens may be misleading but influence the choice of(More)
The coagulase-negative staphylococci and, in particular, Staphylococcus epidermidis, have emerged as major nosocomial pathogens associated with infections of implanted medical devices. These organisms, which are among the most prevalent bacteria of the human skin and mucous membrane microflora, present unique problems in the diagnosis and treatment of(More)
Synthesis of a polysaccharide adhesin by icaADBC-encoded enzymes is currently the best-understood mechanism of staphylococcal biofilm development. In four methicillin-resistant Staphylococcus aureus isolates, environmental activation of icaADBC did not always correlate with increased biofilm production. Moreover, glucose-mediated biofilm development in(More)
A multiplex polymerase chain reaction (PCR), involving detection of the mecA and femB genes, was combined with a novel immunoassay system capable of detecting specific PCR products. The resulting PCR-immunoassay was evaluated in comparison with conventional microbiological techniques used in the routine diagnostic laboratory for the rapid identification of(More)
Biofilm formation in Staphylococcus epidermidis is dependent upon the ica operon-encoded polysaccharide intercellular adhesin, which is subject to phase-variable and environmental regulation. The icaR gene, located adjacent to the ica operon, appears to be a member of the tetR family of transcriptional regulators. In the reference strain RP62A, reversible(More)