Controlling Hospital-Acquired Infection: Focus on the Role of the Environment and New Technologies for Decontamination

SUMMARY

There is increasing interest in the role of cleaning for managing hospital-acquired infections (HAI). Pathogens such as vancomycin-resistant enterococci (VRE), methicillin-resistant Staphylococcus aureus (MRSA), multiresistant Gram-negative bacilli, norovirus, and Clostridium difficile persist in the health care environment for days. Both detergent- and disinfectant-based cleaning can help control these pathogens, although difficulties with measuring cleanliness have compromised the quality of published evidence. Traditional cleaning methods are notoriously inefficient for decontamination, and new approaches have been proposed, including disinfectants, steam, automated dispersal systems, and antimicrobial surfaces. These methods are difficult to evaluate for cost-effectiveness because environmental data are not usually modeled against patient outcome. Recent studies have reported the value of physically removing soil using detergent, compared with more expensive (and toxic) disinfectants. Simple cleaning methods should be evaluated against nonmanual disinfection using standardized sampling and surveillance. Given worldwide concern over escalating antimicrobial resistance, it is clear that more studies on health care decontamination are required. Cleaning schedules should be adapted to reflect clinical risk, location, type of site, and hand touch frequency and should be evaluated for cost versus benefit for both routine and outbreak situations. Forthcoming evidence on the role of antimicrobial surfaces could supplement infection prevention strategies for health care environments, including those targeting multidrug-resistant pathogens.     

Selective spatial attention to left or right hand flutter sensation modulates the steady-state somatosensory evoked potential

Steady-state somatosensory evoked potentials (SSSEPs) were recorded from the scalp of human subjects elicited by 20 and 26 Hz mechanical vibrations applied simultaneously to the index finger of the left (20 Hz) and right hand (26 Hz). Subjects were instructed to attend to the flutter vibration at one finger while ignoring the other finger and to detect rare target events at the to-be-attended finger. The amplitude of the frequency coded SSSEP elicited by the attended vibration was significantly enlarged when attention was focused at the respective finger. This amplitude enhancement with attention was most prominent over fronto-central electrode locations contralateral to the attended finger. This is the first report to show the attentional modulation of the SSSEP amplitude in humans, suggesting an enhancement of neural responses in the sense of flutter with attention. The findings will open a new approach for studying the neural mechanisms of sustained selective attention in somatosensation.     

Update on the prevention and control of community-acquired meticillin-resistant Staphylococcus aureus (CA-MRSA)

The rapid dissemination of community-acquired meticillin-resistant Staphylococcus aureus (CA-MRSA) since the early 2000s and the appearance of new successful lineages is a matter of concern. The burden of these infections varies widely between different groups of individuals and in different regions of the world. Estimating the total burden of disease is therefore problematic. Skin and soft-tissue infections, often in otherwise healthy young individuals, are the most common clinical manifestation of these infections. The antibiotic susceptibilities of these strains also vary, although they are often more susceptible to 'traditional' antibiotics than related hospital-acquired strains. Preventing the dissemination of these organisms throughout the general population requires a multifaceted approach, including screening and decolonisation, general hygiene and cleaning measures, antibiotic stewardship programmes and, in the future, vaccination. The current evidence on the prevention and control of CA-MRSA is appraised and summarised in this review.     

Small cell carcinoma of the kidney: a clinicopathologic study of 14 cases

Small cell carcinoma of the kidney is distinctively rare. We searched pathology files in 2 institutions and found 14 cases of renal small cell carcinoma. The patients' mean age at diagnosis was 59 years (range, 22-75 years); 8 were women, and 6 were men. Patients usually presented with hematuria (n = 6) and abdominal pain (n = 5). The mean tumor size was 7.1 cm (range, 3.5-14.0 cm). The small cell carcinoma was pure in 9 cases and mixed with high-grade urothelial carcinoma in 5 cases. None was associated with any type of renal cell carcinoma. Tumor necrosis was present in all cases, and lymphovascular invasion was identified in 6 cases. The tumor invaded the perinephric adipose tissue in 13 cases and was confined to the kidney in only 1 case. Lymph node metastases were identified in all patients who underwent lymph node dissection (5/5). On immunostains, the small cell carcinoma cells were positive for pancytokeratin (11/12), chromogranin (6/9), and synaptophysin (8/9). Follow-up data were available for 13 patients, and 11 died of small cell carcinoma at a mean of 15 months (range, 4-31 months) after diagnosis. Of the 2 surviving patients, 1 was alive at 5 months after diagnosis, and the other, whose disease was confined to the kidney, was alive with no evidence of disease at 137 months. In summary, renal small cell carcinoma is a highly aggressive disease that often presents at an advanced stage with widespread metastases. Patients usually have a poor clinical outcome despite multimodal therapy. The frequent coexistence of small cell carcinoma with urothelial carcinoma suggests that renal small cell carcinomas may evolve from a preexisting urothelial carcinoma.     

Field efficacy trial of a novel HVT-IBD vector vaccine for 1-day-old broilers

Two vaccination programmes for infectious bursal disease (IBD) were compared in broiler chickens with maternal immunity, placed on two farms. A turkey herpes virus (HVT)-IBD vector vaccine was administered by the subcutaneous route, at the hatchery, into the chicks of farm A at the age of 1 day. On farm B, an attenuated intermediate live IBD vaccine was given orally at the ages of 17 and 24 days. The vaccine uptake was monitored via serology and bursa/body weight ratio evolution, as well as PCR-based viral IBDV detection in the bursa of Fabricius at various time points. It was also verified by an experimental very virulent IBDV challenge performed at the age of 30 days in birds transferred from the farms with appropriate control groups in a laboratory. An immunity gap was observed in birds from farm B between the decay of the passive and the rise of the active immunity based upon serological data. The level of protection against challenge is not possible to establish in this farm as the reduction of the bursa/body weight ratio observed could be due to the residual pathogenicity of the vaccine strain or the challenge as well. This immunity gap was not present on farm A showing higher serological titres at the ages of 26 and 45 days via a suitable ELISA test and 93% protection against the very virulent challenge at the age of 30 days was observed. The maternal immunity interfering with the live IBDV vaccine replication had no detectable effect on the vector vaccine take.     

Epidemic syphilis exhibits diverse manifestations

There are recent reports of a sustained increase in the incidence of syphilis around the world, including in the Australian cities of Sydney and Melbourne.