The use of contrast-enhanced ultrasound in the characterisation of focal liver lesions.

PURPOSE: To determine the potential application of contrast-enhanced ultrasound in the characterisation of focal liver lesions encountered in radiological practice at a district general hospital. MATERIALS & METHODS: Retrospective analysis of 68 sequential patients undergoing contrast-enhanced ultrasound (CEUS) of liver. All patients were referred for CEUS following identification of 1 or more focal liver lesions on conventional ultrasound or CT imaging. After baseline US examination (Acuson), a bolus of 1.0-2.4 ml of SonoVue (Bracco, UK) was administered intravenously. CEUS images were obtained during arterial, portal venous and delayed phases. Patients were followed up for a mean period of 6 months. The CEUS diagnosis was compared to that indicated by other imaging modalities, histopathology, and clinical follow up. RESULTS: CEUS correctly identified malignant liver lesions in 19 patients, with the final diagnosis confirmed by histopathology in 5 cases and clinico-radiological follow up in 14 cases. 47 patients were correctly identified with benign liver lesions on CEUS imaging, with all these cases confirmed on clinico-radiological follow up. In the detection of malignancy, the sensitivity was 95.0% and the specificity was 97.9%. CONCLUSIONS: In our experience to date, contrast-enhanced ultrasound imaging is highly accurate in characterising malignant and benign focal liver lesions. It therefore has significant potential for utilisation in most general radiology departments.

Father and son. The origins of Strange case of Dr Jekyll and Mr Hyde.

In Strange Case of Dr Jekyll and Mr Hyde Robert Louis Stevenson created, out of one of his own dreams, the most famous pre-Freudian case study of the divided self. The present essay explores the roots of that work in Stevenson's lifelong difficulty in separating from his moody, conflicted, and passionately possessive father. Out of a matrix of religious guilt and social conformity, Stevenson struggled to create and define his own identity as a writer, a struggle that ran counter to many of his beloved father's deepest needs and led to sharp clashes, accompanied by periods of severe depressive and physical illness in both. Stevenson's creative block during his father's final depression and dementia was broken only by the nightmare that became Jekyll and Hyde, which enabled him to give enduring literary expression to the disavowed rage, guilt, and sense of deformity and fractured identity endemic to their internalized relationship. It may also have functioned as an act of exorcism and expiation that helped him recover rapidly from his father's death and exploit more productively the few years that were left to him.

Evaluation of disc diffusion and Etest for determining the susceptibility of Staphylococcus aureus to mupirocin.

The susceptibilities to mupirocin of 102 selected clinical isolates of Staphylococcus aureus and of control strain S. aureus NCTC 6571 were determined by disc diffusion (using discs containing 5, 15, 25, 30, 50 and 200 microg of mupirocin) and Etest and the results were compared with MICs determined using an agar incorporation method. On the basis of agar incorporation MICs, 42 isolates were sensitive to mupirocin (MIC < or = 4 mg/L), 39 showed low-level resistance (MICs = 8-128 mg/L) and 22 were highly resistant (MICs > or = 256 mg/L) and contained the mupA resistance gene. Using Stokes' criteria, none of the discs used gave major errors (sensitive isolates classified as highly resistant) or very major errors (highly resistant isolates classified as sensitive) in assigning a category of susceptibility, but minor errors (a difference of one category) were noted with all strengths. The best correlation with agar incorporation MIC was obtained with 25 microg mupirocin discs, which classified correctly 98 (95%) isolates, while worse correlations were noted with 5 microg and 200 microg discs which are the only types currently available commercially, for which there were 47 and 30 minor errors, respectively. The MICs found by Etest were the same as, or lower than, those determined by agar incorporation. Etests classified correctly all 42 mupirocin-sensitive isolates, 19 (49%) low-level resistant isolates and 16 (73%) highly resistant isolates. Two isolates that contained the mupA gene and showed agar incorporation MICs of 256 mg/L and 512 mg/L were not classified as highly resistant by any of the diffusion methods used. Agar incorporation MIC determination, possibly supported by detection of the mupA gene, offers the most effective means of identifying high-level mupirocin resistance in S. aureus, although the Etest also proved to be reproducible. However, we conclude that 25 microg discs warrant further evaluation for possible use in clinical laboratories, as they appear to be more reliable than the discs currently available.

Clinical teaching models: a review of the role of preceptor in the undergraduate nursing program.

The relatively recent transition of nursing education in Australia from a hospital-based apprenticeship, into the higher education sector has been marked by an acknowledgement that the clinical knowledge of undergraduate student nurses is at risk of becoming separated from their theoretical knowledge. The length of time which student nurses spend on clinical placements experiencing the complexities of the clinical world is diminishing, partly in response to economic constraints on universities and health care agencies. This contrasts with an expectation that students will be safe and competent practitioners immediately on graduation. The preceptor model is being increasingly used in the final semester of the undergraduate-nursing course to facilitate the development of critically thinking, reflective practitioners. This paper examines some of the assumptions that have been made about preceptorship in its adoption into the Australian nursing education context. It is concluded that further research into the experiences of registered nurses in the preceptor role may increase our understanding of the potential of preceptorship as a clinical teaching model which can meet the future needs of both nursing education and nursing service.

Extended-spectrum beta-lactamase-producing Klebsiella pneumoniae strains causing nosocomial outbreaks of infection in the United Kingdom.

Representative isolates from 10 distinct extended-spectrum beta-lactamase-producing strains of Klebsiella pneumoniae that caused hospital outbreaks in the United Kingdom from 1991 to 1994 were examined for relationships between their enzymes and plasmids. The beta-lactamases were identified by a combination of isoelectric focusing and gene sequencing. SHV-2 beta-lactamase was produced by isolates from four outbreaks, SHV-5 was involved in three, and SHV-4, TEM-15, and TEM-26 were involved in one outbreak each. All of the extended-spectrum beta-lactamases were encoded by self-transmissible plasmids, with sizes ranging from about 70 to 160 kb. No similarities between the restriction digest patterns of the extended-spectrum beta-lactamase-encoding plasmids were detected, except to some extent between those that produced TEM-15 and TEM-26. Thus, outbreaks of hospital infection with these organisms in the United Kingdom from 1991 to 1994 involved distinct organisms and resistance plasmids and appeared to be unrelated.

Physician attitudes toward cost containment. The missing piece of the puzzle.

A survey of 720 physicians practicing in central and western Massachusetts was undertaken to examine their attitudes toward cost-containment measures. The majority of physicians felt that major techniques (58%), major procedures (57%), inappropriate ordering of diagnostic tests (48%), and malpractice concerns (47%) were very important contributors to increasing health care costs. Physician age, practice affiliation, and specialty area were related to the perceived importance of these factors. In addition, while there was a uniform lack of prior training in cost-containment measures, 48% of all physicians felt that courses in cost-containment techniques would be worthwhile. These results suggest a variety of concerns and issues that need to be considered when attempting to modify the cost-containment attitudes and practices of physicians.

Hypersensitivity to tobacco glycoprotein in human peripheral vascular disease.

One hundred and sixty-four patients with peripheral vascular disease (PVD) were skin tested with a purified tobacco glycoprotein (TGP). A basophil degranulation test (BDT) was also performed to assess in vitro reactivity to TGP. Immediate skin test hypersensitivity to TGP was found in 18 of 164 (11%) patients with radiologically demonstrable PVD. BDT was positive in 25/42 (60%) smokers as opposed to 6/23 (24%) nonsmokers (p less than 0.01). Twenty-one of 49 (43%) skin test-negative and 10/11 (91%) skin test-positive patients wih PVD had a positive BDT (p less than 0.02). Only 1/34 (3%) patients with negative BDT had a positive skin test. Skin test-positive patients had significantly higher BDT at 0.01 and 0.001 microgram/ml TGP in vitro compared to skin test-negative patients (p less than 0.01). When PVD was graded by arteriography, one of 11 patients with "mild," 11/87 with "moderate" and 4/20 with "severe" PVD were skin test-positive to TGP (p less than 0.01 "mild" vs "moderate"; p less than 0.05 "mild" vs. "severe"). These differences could not be attributed to age, sex, atopy or smoking status. Reactivity to TGP exists in a proportion of patients with PVD and may be causally related in such cases to the development of atherosclerotic vascular disease.