BRUCELLOSIS COMPLICATED BY AORTIC VALVE ENDOCARDITIS

A 30 year old veterinary surgeon developed a febrile illness with serological evidence of Brucellosis. He was known to have aortic valve disease and during the course of the illness, the clinical features of endocarditis became evident, with a vegetation visible echocardiographically on the aortic valve. Because of persisting fever despite appropriate antibiotic therapy, aortic valve replacement with a viable cryopreserved allograft aortic valve was undertaken. Organisms consistent with Brucella species were demonstrated in the excised vegetation. The patient received a six week course of antibiotics and his post-operative course was uneventful.     

The Role of Stigma in Access to Health Care for the Poor

Context

The Affordable Care Act provides new Medicaid coverage to an estimated 12 million low-income adults. Barriers to access or quality could hamper the program''s success. One of these barriers might be the stigma associated with Medicaid or poverty.

Methods

Our mixed-methods study involved 574 low-income adults and included data from an in-person survey and follow-up interviews. Our analysis of the interviews showed that many participants who were on Medicaid or uninsured described a perception or fear of being treated poorly in the health care setting. We defined this experience as stigma and merged our qualitative interviews coded for stigma with our quantitative survey data to see whether stigma was related to other sociodemographic characteristics. We also examined whether stigma was associated with access to care, quality of care, and self-reported health.

Findings

We were unable to identify other sociodemographic characteristics associated with stigma in this low-income sample. The qualitative interviews suggested that stigma was most often the result of a provider-patient interaction that felt demeaning, rather than an internalized sense of shame related to receiving public insurance or charity care. An experience of stigma was associated with unmet health needs, poorer perceptions of quality of care, and worse health across several self-reported measures.

Conclusions

Because a stigmatizing experience in the health system might interfere with the delivery of high-quality care to new Medicaid enrollees, further research and policy interventions that target stigma are warranted.     

DESIGNING STUDIES FOR DOSE RESPONSE

‘Dose response’ refers to the regression of a response on a stimulus. We review a number of options for dose–response designs, and compare various designs which may be used in practice. We start with two group designs. Next, we introduce basic optimal approximate design theory for simple linear and quadratic regression illustrating different criteria of optimality and their effect on the allocation of the levels of the dose. Then we obtain the efficiencies of these optimal approximate designs and some simple designs which have intuitive appeal (symmetry, equal spacing of treatments, reduced numbers of observations at the highest and lowest doses).     

A TECHNIQUE FOR MEASURING EPIDEMIOLOGICALLY USEFUL FEATURES OF BIRTHWEIGHT DISTRIBUTIONS

Birthweight distributions have been conceptualized as a predominant Gaussian distribution contaminated in the tails by an unspecified ‘residual’ distribution. Acknowledging this idea, we propose a technique for measuring certain features of birthweight distributions useful to epidemiologists: the mean and variance of the predominant distribution; the proportions of births in the low- and high-birthweight residual distributions, and the boundaries of support for these residual distributions. Our technique, based on an underlying multinomial sampling distribution, involves estimating parameters in a mixture model for the multinomial bin probabilities after having chosen the support of the residual distribution with a model selection criterion. A modest simulation study and experience with a few actual datasets indicate that use of a Bayesian information criterion (BIC) as model selection criterion is superior to use of Akaike's information criterion (AIC) in this application.     

MUTATION OF THE VHL GENE IS ASSOCIATED EXCLUSIVELY WITH THE DEVELOPMENT OF NON-PAPILLARY RENAL CELL CARCINOMAS

To define the possible role of the VHL gene in the development of sporadic renal cell carcinomas, 91 different parenchymal tumours of the kidney have been investigated for mutation of the VHL gene by single strand conformation polymorphism (SSCP) and/or heteroduplex (HD) techniques. Chromosome 3p deletion was detected in 98 per cent of non-papillary renal cell carcinomas and in 25 per cent of chromophobe renal cell carcinomas. In 22 of the 43 non-papillary renal cell carcinomas, abnormally migrating DNA bands were detected by SSCP and/or HD analysis. No mobility shift was seen in any of the 23 chromophobe renal cell carcinomas. In addition, 15 papillary renal cell tumours and ten renal oncocytomas, which are characterized by genetic changes other than loss of chromosome 3p sequences, were analysed for mutation of the VHL gene. None of these tumours showed abnormal migration patterns. The results indicate that mutation of the VHL gene is associated exclusively with the development of non-papillary renal cell carcinoma.     

IMMUNOHISTOCHEMICAL ASSAY FOR OESTROGEN RECEPTORS IN PARAFFIN WAX SECTIONS OF BREAST CARCINOMA USING A NEW MONOCLONAL ANTIBODY

The aim of this study was to evaluate the utility of a new monoclonal antibody (AER311) that targets the oestrogen receptor (ER) in an immunohistochemical assay (IHA) applied to breast cancers. Ninety-seven cases of invasive ductal carcinoma were studied by AER311-IHA using a pressure-cooking antigen retrieval technique applied to formaldehyde-fixed, paraffin-embedded tissue sections; immunostaining was assessed by semi-quantitative scoring ( H score). There was 80 per cent concordance between the ER status measured by dextran-coated charcoal (DCC) assay and AER311-IHA, with 63/97 (65 per cent) tumours positive and 15/97 (15 per cent) tumours negative by both assays. Of the 12 DCC-positive cases that were negative by AER311-IHA, 11 were borderline positive (3–8 fmol/mg). Similarly, six of seven DCC-negative cases that scored positive by AER311-IHA had only borderline positive H scores (<50). When AER311-IHA was compared with 1D5-IHA, there was good concordance in ER status (77 per cent) and a significant correlation ( r =0·7, P <0·001) between H scores. Nevertheless, the correlation between ER level determined by AER311-IHA and that measured by DCC ( r =0·53, P <0·001) was higher than that for 1D5-IHA ( r =0·32, P =0·002). AER311-IHA can therefore provide reliable information about the ER status of breast carcinoma on paraffin sections and is an acceptable alternative to other commercially available monoclonal antibodies.     

Intestinal ischaemia associated with carcinoid tumour: A case report with review of the pathogenesis

A case of ischaemic ileal perforation associated with a macroscopically unapparent ileal carcinoid is described. The mesenteric vessels were non-pulsatile at operation but were anatomically patent when examined by the pathologist. The characteristic elastic perivascular sclerosis of mesenteric vessels, which probably caused a functional vascular obstruction, was only discovered after the histological sections were reviewed. The true incidence of this rare condition may be higher than previously suspected because the perivascular sclerosis can easily be overlooked. Awareness of the association between carcinoid tumour and mesenteric ischaemia may lead to early surgery and an improved outcome.