Predictors of Repeat Emergency Department Visits by Elders

Objective: To determine which characteristics of older patients who use a hospital ED are associated with repeat visits during the 90 days following the index visit.
Methods: The study was conducted in the ED of a 400-bed university-affiliated acute care community hospital in Montreal. Patients aged ≥75 years who visited the ED between 08:00 and and 16:00 on a convenience sample of days over an 8-week period (July and August 1994) were assessed using a questionnaire, physical and cognitive status instruments, and a functional problem checklist. The hospital's administrative database was used to identify repeat visits during the 90 days following the ED visit. The representativeness of the sample was assessed by analyses of ED visits made by 4,466 persons aged ≥65 years during a 12-month period (September 1993 to August 1994) using the hospital's administrative database.
Results: 256 patients aged ≥75 years visited the ED during the study period and 167 were assessed. Of these, 54 (32%) were admitted to the hospital. Among the 113 patients released from the ED, 27 (24%) made repeat visits during the next 90 days. In univariate analyses, repeat visits were significantly associated with the number of functional problems, cognitive impairment, and previous ED visits. In multiple logistic regression, male gender, living alone, and number of functional problems were independent predictors of repeat visits. In the administrative data analyses, nighttime arrival to the ED for the index visit was significantly associated with repeat visits.
Conclusions: Self-reported risk factors can help to identify a group of elders likely to make repeated ED visits; the development of a screening instrument incorporating questions on these problems and implementation of appropriate interventions might improve these patients' quality of life and reduce the demand for further ED care in this age group.     

Common bile duct calculi: updated experience with dissolution with methyl tertiary butyl ether

The authors describe their experience with methyl tertiary butyl ether (MTBE) in a larger series of patients than previously reported in order to acquaint physicians with both its effectiveness for dissolution of common bile duct calculi and the limitations of its use. Ten patients with 13 biliary calculi underwent percutaneous stone dissolution treatment with the experimental cholesterol solvent, MTBE. Three stones completely dissolved within 30 minutes, seven were reduced in size, and three were visibly unaffected. All stones not completely dissolved were easily extracted by means of a stone basket except for one in a patient taken to surgery. Although MTBE perfusion is an effective technique for management of biliary calculi, practitioners should be aware that its use is quite time consuming and its odor difficult to control.     

The Association of Different Measures of Insulinaemia with Vascular Risk Factors in Healthy Normoglycaemic Normotensive Non-obese Men and Women

Hyperinsulinaemia is said to be a risk factor for cardiovasculardisease, but the extent to which different insulinaemic measuresare associated with vascular risk factors in ostensibly healthyindividuals, and whether they operate independently in men andwomen, remains uncertain. The association between risk factors and various insulinaemicmeasures was examined in 148 men and 118 women who were normoglycaemic,normotensive, and non-obese (body mass index in men <27,in women <25). A 75 g glucose tolerance test was administeredafter blood sampling for fibrinogen, lipids, lipoproteins andinsulin. Insulin was also measured after 1 and 2 hours. Significantunivariate correlations (p<0.01) were most consistently recordedbetween insulinaemic measures and fasting serum triglyceridesin men and women, whilst systolic blood pressure only correlatedwith insulinaemia in women, and diastolic blood pressure correlatedwith fasting and 2 hour insulinaemic measures in men and women.Inconsistent associations were noted with total serum cholesterolin men and women, with high density lipoprotein cholesterol,body mass index, apoprotein B and A1 in men, and with fibrinogenin women. Age was not correlated with any insulinaemic measurein men or women. Differences in vascular risk factors between quintiles of theinsulinaemic measures were examined, after correction for bodymass index. The dominant association with fasting and post-glucoseload insulinaemic measures was with triglycerides, especiallyin women, with less frequent graded differences between quintilesobserved for total cholesterol, and diastolic and systolic bloodpressures in men and women. The incidence of other risk factors often only differed in thelowest or highest quintile in comparison to other quintiles,suggesting a threshold rather than a graded effect. Furthermore,differences in HDL cholesterol and apoprotein B were only recordedfor top quintiles of post-glucose challenge/integrated insulinaemicmeasures in men, whilst serum fibrinogen concentrations onlydiffered significantly in women in the top insulinaemic areaunder the curve quintile. In the absence of additional risk factors such as diabetes,hypertension and obesity, insulinaemic measures are not consistentlyrelated to blood pressure and measures of lipid metabolism andcoagulation, and are thus a weak predictor of other cardiovascularrisk factors. The vascular risk profile associated with insulinappears somewhat different in apparently healthy men and women.     

Clinical Recurrences After Successful Accessory Pathway Ablation:

Dormant Accessory Pathways. Introduction : Recurrence of clinical symptoms after radiofrequency catheter ablation of an accessory atrioventricular pathway (AP) may be due to the late manifestation of an additional AP that was not detected during the initial ablation session. It was the purpose of this study to elucidate the phenomenon of these "dormant" APs.
Methods and Results : Of 1280 consecutive patients who underwent radiofrequency catheter ablation of an AP, 54 patients (4.2 %) developed clinical symptoms postablation, necessitating a repeat ablation session. Recurrence of conduction over the AP targeted al the initial ablation session was found in 45 patients, whereas in the other 9 patients (0.7%) the manifestation of a previously unnoticed AP had caused symptom recurrence. Retrospective analysis of the data from these patients' ablation sessions revealed that the late manifesting AP was ablated at a site clearly different from that of the initially targeted AP, and that the manifestation of conduction over a previously "dormant" AP occurred significantly later than the recovery of a presumably ablated AP. Seven (78%) of the 9 "dormant" APs were concealed, and none exhibited decremental conduction properties.
Conclusion : The incidence of clinical recurrences mediated by the late manifestation of conduction over a previously "dormant" AP is low. The lack of an anatomic vicinity of these predominantly concealed APs with the initially targeted AP and the lack of evidence for their presence during the initial ablation session suggest intermittent conduction as the most likely explanation for their late manifestation.     

Herpetic croup: two case reports and a review of the literature

Croup is an acute infectious illness usually occurring in children; it is characterized by brassy cough and stridor. The main pathogens include mainly parainfluenza and influenza viruses. Recently there have been reports of prolonged croup caused by the herpes simplex viruses. We report two cases of prolonged croup due to herpes simplex types 1 and 2. We also review and summarize the reported pediatric cases of herpetic croup.     

Monomethylfumarate affects polarization of monocyte-derived dendritic cells resulting in down-regulated Th1 lymphocyte responses

Psoriasis vulgaris, a type-1 cytokine-mediated chronic skin disease, can be treated successfully with fumaric acid esters (FAE). Beneficial effects of this medication coincided with decreased production of IFN-gamma. Since dendritic cells (DC) regulate the differentiation of T helper (Th) cells, this study focussed on effects of monomethylfumarate (MMF, bioactive metabolite of FAE) on polarization of monocyte-derived DC. MMF-incubated, lipo-polysaccharide-stimulated DC (MMF-DC) produced dramatically (p<0.05) reduced levels of IL-12p70 and IL-10 (8+/-4% and 20+/-4%, respectively) compared to control DC. MMF-DC were mature. MMF affected polarization of DC irrespective of polarization factor(s) and ligands for the various Toll-like receptors used. Coculture of MMF-DC with naive and primed allogenous Th cells resulted in lymphocytes producing less IFN-gamma, i.e. 59% and 54% of that by the respective Th cells cocultured with control DC. IL-4 production by primed, but not naive Th cells cocultured with MMF-DC was decreased as compared to cocultures with control DC. IL-10 production by naive and primed Th cells cocultured with MMF-DC and control DC did not differ. In addition, MMF inhibited LPS-induced NF-kappaB activation in DC. Together, beneficial effects of FAE in psoriasis involve modulation of DC polarization by MMF such that these cells down-regulate IFN-gamma production by Th cells.     

Immunocytochemical analysis of cellular responses to BCG.

The study reported here was performed to find out whether changes in the number of mycobacteria in various organs of BCG-infected mice can be related to changes in the phenotype of monocytes, macrophages and lymphocytes in the blood, various tissues, and peritoneal cavity and to the formation of granulomas in the spleen, liver and lungs. The relative amounts of various antigens on the leukocytes were assessed semi-quantitatively after immunocytochemical detection of the binding of monoclonal antibodies. Granuloma formation was determined after immunocytochemical staining of cells in sections of liver and lung tissue with a monoclonal antibody against the common leukocyte antigen and in sections of the spleen with a monoclonal antibody against the Mac-2 antigen. The results showed that during the first week of infection the number of BCG in spleen, liver and lungs declined considerably. Multiplication of mycobacteria during the second week of infection was associated with decreased expression of antigen F4/80 and increased expression of Ia antigen and Mac-2 antigen by blood monocytes and macrophages. Reduction of the numbers of BCG in the spleen and liver during the third week after i.v. injection of BCG and in lungs during the fourth week of the infection was found to be correlated with the degree of granuloma formation in these organs. After intravenous injection of killed BCG no changes were observed in the phenotype of monocytes and the macrophages in spleen, liver, lungs and peritoneal cavity. These mice showed considerably less granuloma formation than BCG-infected mice. The present results indicate that live but not killed mycobacteria induce macrophage activation.     

Charcot-Marie-Tooth phenotype produced by a duplicated PMP22 gene as part of a 17P trisomy-translocation to the X chromosome

The Charcot-Mane-Tooth disease type 1A (CMTlA) phenotype is most often associated with a 1.5 megabase (mb), tandem duplication of chromosome 17 band p12 (17˜12). The prevailing hypothesis is that the demyelinating neuropathy results from a dosage effect of the peripheral myelin protein gene PMP22 which is included within this duplication. We present a patient with clinical and electrophysiological features ofCMTlA in whom an extra PMP22 gene resulted from a rare unbalanced translocation of 17p to the X chromosome. This finding further supports the hypothesis of gene dosage as the basis for CMTlA. More-over, this case highlights the importance of fluorescence in siiu hybridization (FISH) as an alternative molecular technique in the diagnosis of CMTlA.     

Effect of IFN-gamma and endogenous TNF on the histopathological changes in the liver of Listeria monocytogenes-infected mice.

During primary infection of mice with Listeria monocytogenes, the bacteria proliferate extensively in the liver resulting in the development of inflammatory lesions in this organ. In the present study, the effect of interferon-gamma (IFN-gamma) on the development of these lesions, and the involvement of endogenous tumour necrosis factor-alpha (TNF-alpha) in the IFN-gamma-induced effects were evaluated. During an infection of naive mice with L. monocytogenes, two types of inflammatory lesions in the liver could be distinguished: large necrotic lesions consisting of granulocytes and/or exudate macrophages and small lesions containing mainly mature macrophages, i.e. BM8-expressing cells. Necrotic lesions were characterized by the presence of CD11b-expressing cells and consisted mainly of granulocytes during days 1 and 2 of infection and thereafter of exudate macrophages. The lesions consisting of mature macrophages and lymphocytes were not associated with necrosis and were called granulomatous lesions. Some of the granulomatous lesions contained many cells that expressed Ia antigen, i.e. activated cells. Treatment of mice with recombinant (r)IFN-gamma before injection of L. monocytogenes resulted in a decrease in the number of necrotic lesions and an increase in the number of granulomatous lesions in the liver, which was accompanied by a reduced bacterial proliferation in the liver. The effect of rIFN-gamma on the development of the various types of inflammatory lesions in the liver during infection with L. monocytogenes was abrogated by anti-TNF-alpha antibody and this antibody abrogated the rIFN-gamma-induced reduction of bacterial proliferation in the liver as well. Together, the results demonstrate that endogenous TNF-alpha plays a key role in the effects of rIFN-gamma on the inflammatory response in the liver during an infection with L. monocytogenes.     

Endogenous tumor necrosis factor alpha is required for enhanced antimicrobial activity against Toxoplasma gondii and Listeria monocytogenes in recombinant gamma interferon-treated mice.

In vitro studies have shown that macrophages stimulated with recombinant gamma interferon (rIFN-gamma) produce tumor necrosis factor alpha (TNF-alpha), which in an autocrine fashion activates these cells. The aim of the present study was to determine whether endogenously formed TNF-alpha also is required for rIFN-gamma-induced macrophage activation and enhanced antimicrobial activity in vivo. After an intraperitoneal injection of rIFN-gamma into CBA/J mice, their peritoneal macrophages released enhanced amounts of NO2- and inhibited the intracellular proliferation of Toxoplasma gondii. Injection of neutralizing antibodies against TNF-alpha simultaneously with the rIFN-gamma completely inhibited both the release of NO2- by macrophages and their toxoplasmastatic activity. Similar results were observed after intraperitoneal injection of a competitive inhibitor of L-arginine, NG-monomethyl-L-arginine, together with rIFN-gamma, demonstrating that in vivo L-arginine-derived reactive nitrogen intermediates are essential for the induction of toxoplasmastatic activity. Intravenous injection of rIFN-gamma inhibited the growth of Listeria monocytogenes in the livers and spleens of mice; this effect was abrogated by antibodies against TNF-alpha. Intravenous injection of a large dose of rTNF-alpha resulted in a decrease in the number of bacteria in the liver and spleen, but an injection of rIFN-gamma and rTNF-alpha did not result in enhanced inhibition of the proliferation of L. monocytogenes. Together, the results of the present study are the first to demonstrate that endogenous TNF-alpha is required in vivo for the expression of macrophage activation with respect to the release of reactive nitrogen intermediates and toxoplasmastatic activity and for enhanced listericidal activity in the livers and spleens of mice stimulated with rIFN-gamma.