Effects of Microplastics on Microbial Community in Zhanjiang Mangrove Sediments

Microplastics are easily consumed by marine animals, thereby entering the food chain and endangering animal health. However, there are few studies focusing on the effects of microplastics in mangrove sediments on microbial communities. In order to study the influence of microplastics on microorganisms, microplastics and microorganisms were extracted from Zhanjiang (Guangdong Province, China) mangrove sediments and analyzed. The results showed that there were differences in Shannon and Simpson indices of the microbial community in microplastics (p < 0.05), and there were also differences between JG30_KF_CM45 and Natranaerovirga at the genus level, indicating that microplastics may affect the diversity and composition of microorganisms in sediments. In addition, FAPROTAX function prediction analysis showed that microplastics may affect the nitrification of microbial communities. The results from this study indicate that microplastics affected the diversity and richness of microorganisms in mangrove sediments, which provides an experimental basis for the relationship between microplastics and microorganisms.

The Status of Polychlorinated Biphenyls (PCBs) Extract from Zhanjiang Mangrove Sediments and the Effects on Tissue Structure and Inflammatory Cytokines in Zebrafish Liver

Polychlorinated biphenyls (PCBs) are released into the environment from a wide range of sources. The aim of the present study was to investigate the effect of the PCBs extracted from the Zhanjiang mangrove sediments on the immune function of zebrafish. The sediments were collected from 3 mangrove forest points in Zhanjiang (Guangdong Province, China), and the results showed that PCB153 was detected in the sediments of the Guangdong Zhanjiang Mangrove National Nature Reserve (MNNR) and Gaoqiao Mangrove Reserve (GMR), while PCB101, PCB112, PCB155, and PCB198 were detected in the sediments of the Leizhou Peninsula (LP). The zebrafish were exposed to different concentrations of PCBs, i.e., control group, positive control group (Aroclor1254; 10 μg/L), low dose group (LD; 0.6 μg/L), medium-dose group (MD; 3.0 μg/L) and high dose group (HD; 15 μg/L) for 14 days. As compared to the control group, the liver index increased significantly in all PCB treated groups. The liver tissue structure was destroyed in all PCB-treated groups as compared to the control group. In addition, the relative mRNA expression of the target genes (IL-1β, IL-8, and TNF-α) was significantly expressed in each concentration group. Therefore, these findings suggest that exposure of zebrafish to PCBs can destroy the liver histology and increase the liver index and mRNA expression of inflammatory cytokines in a dose and time-dependent manner.

Prognostic significance of polyvascular disease in patients admitted with acute decompensated heart failure: the ARIC Study Community Surveillance

Introduction

The prevalence and outcomes of polyvascular disease (PVD) in patients admitted with acute decompensated heart failure (ADHF) have not been previously reported, nor is it known whether associations differ for heart failure (HF) with reduced vs. preserved ejection fraction (HFrEF vs HFpEF, respectively).

Purpose

To investigate the relationship between atherosclerotic involvement of multiple arterial territories and mortality in patients hospitalized with ADHF.

Methods

The Atherosclerosis Risk in Communities (ARIC) study conducted hospital surveillance of adjudicated heart failure in 4 US areas from 2005–2014, with events verified by physician review. Medical histories were abstracted from the hospital record. PVD was defined by coexisting disease in ≥2 arterial beds, identified by prevalent coronary artery disease, peripheral arterial disease, and cerebrovascular disease. Mortality hazards of PVD vs. no PVD were analyzed separately for HFpEF and HFrEF, with adjustment for age, race, sex, year of admission and geographic region. All analyses were weighted by the inverse of the sampling probability.

Results

Of 24,936 ADHF hospitalizations (52% female, 32% Black, mean age 75 years), 19% had PVD (22% among HFrEF hospitalizations, 17% among HFpEF hospitalizations), Figure 1. There was an increasing trend in 1-year mortality with 0, 1 and ≥2 arterial bed involvement, both for patients with HFrEF (29% to 32% to 38%; P-trend=0.0006) and HFpEF (26% to 32% to 37%; P-trend &lt;0.0001). After adjustments, PVD was associated with a 20% higher hazard of 1-year mortality in patients with HFrEF (HR=1.23; 95% CI: 1.06–1.44) and a 30% higher hazard in patients with HFpEF (HR=1.33; 95% CI: 1.09–1.63), with no significant interaction by HF type (P-interaction = 0.5).

Conclusion

Patients hospitalized with ADHF and coexisting PVD have an increased risk of death, irrespective of HF type. Clinical attention should be directed toward PVD, with secondary prevention strategies enacted to improve the prognosis of this vulnerable population.

Funding Acknowledgement

Type of funding sources: Public Institution(s). Main funding source(s): National Institutes of Health Distributions of arterial diseaseTrends in 1-year mortality outcomes

Increasing prevalence of diabetic peripheral angiopathy and complications in hospitalized patients in the United States

Objectives

We aim to assess prevalence of diabetes related peripheral arterial disease and associated outcomes in hospitalized patients in the United States.

Methods

Trends in hospitalizations in diabetic patients with PAD were determined using the 2003–2017 National Inpatient Sample database. Hospital outcomes including diabetic ulcer incidence, amputations, and revascularizations were analyzed.

Results

The analysis included 10,303,673 hospitalizations in diabetic patients with PAD (DMPAD) during the study period. Prevalence of PAD among patients with diabetes increased over time (p&lt;0.001). The prevalence of foot ulcers in diabetics have also increased over time (p&lt;0.001). The incidence of amputations in patients with diabetes showed a decreasing trend with increasing prevalence of revascularizations from 2003 to 2009. Since 2010 however, rising rates of amputations, both minor and major are seen, especially in younger populations (age 18–49). Hospital costs for amputations have increased ($6.6 billion in 2003 vs $ 14.8 billion in 2017) as well as the costs for revascularization (6.1 billion in 2003 vs $13 billion in 2017) during the study period (p&lt;0.001).

Conclusions

In this analysis of patients with DMPAD, an alarming rate of disease prevalence and in-hospital limb outcomes, including costs, are realized in the current era.

Funding Acknowledgement

Type of funding sources: None.

Terpinen4-ol inhibits heat stress induced inflammation in colonic tissue by Activating Occludin, Claudin-2 and TLR4/NF-κB signaling pathway

Heat stress has severe implications on the health of mice involving intestinal mucosal barrier damage and dysregulated mucosal immune response. This study was designed with long-term heat stress to detect the protective effect of terpinen4-ol on body weight, colon length, organ index, morphological structure, inflammatory cytokines expression, Claudin-2, Occludin, and TLR4 signaling pathway of colonic tissue in mice under heat stress. A study found that oral administration of terpinen4-ol helped against mortality and intestinal inflammation in a mouse model of acute colitis induced by heat stress (40 °C per day for 4 h) exposed for 14 consecutive days. The mice were divided into five groups including control, heat stress, terpinen4-ol low dose (TER LD: 5 mg/kg), medium dose (TER MD: 10 mg/kg), and high dose (TER HD: 20 mg/kg) group. Our study showed that the heat-stress terpinen4-ol group had improved body weight, colon length, and organ index, the number of white blood cells, lymphocytes, and neutrophils in the blood as compared to the heat stress group. In addition, results showed that heat stress upregulated the expression of TLR4, p65, TNF-α, and IL-10. While, in mice receiving the oral administration of terpinen4-ol, the production of TNF-α, IL-10, TLR4, and p65 was suppressed on day 1, 7, and 14 of heat stress. In addition Claudin-2, Occludin mRNA levels were upregulated in mice receiving terpinen4-ol on day 1, 7, and 14 of heat stress. Furthermore, the IL-6, IL-10, TNF-α serum levels were also upregulated in mice under heat stress, but in mice receiving the oral administration of terpinen4-ol, the IL-6, IL-10, TNF-α level was down-regulated on day 1, 7, and 14 of heat stress. Histomorphological examination found that as compared to the control group, the muscle layer thickness and villi height of mice in the heat stress group were significantly reduced, while the changes of the above indicators in the terpinene4-ol groups were improved than those in the heat stress group. In conclusion, the terpinen4-ol has a protective effect on colonic tissue damage induced by heat stress.

Prevalence and antibiotic resistance of Salmonella spp. in South Punjab-Pakistan

Present study aimed at investigating the magnitude of the prevalence and antibiotic resistance among four Salmonella spp. i.e., S. typhi, S. paratyphi A, S. paratyphi B and S. typhimurium. Raw milk and environment samples were collected from the five districts of southern part of the province of Punjab in Pakistan i.e., Multan, Bahawalpur, Lodhran, Dera Ghazi Khan and Muzaffargarh. Extent of antibiotic resistance was also determined and classified as resistant, intermediate and susceptible. District–wise prevalence data on Salmonella spp. in milk and environmental samples indicated higher S. typhi, S. paratyphi B and S. typhimurium count in Bahawalpur, D.G. Khan and Muzaffargarh districts, respectively. Amongst 13 tested antibiotics, chloramphenicol and ofloxacin were found to be the most susceptible against Salmonella spp. Increased emergence of antibacterial resistance was noted with respect to the type of antibiotics among Salmonella spp. isolates. The study suggests serious interventions to be practiced by the farmers and raw milk vendors in animal husbandry and milk marketing, respectively to curb the burden of Salmonella spp. prevalence in milk. Further, active engagement of animal health division and enforcement agencies to ensure sagacious use of antibiotics at farm level may also help in containment of antimicrobial resistance in Salmonella spp.

Cause and risk factors for readmissions after transcatheter aortic valve replacement

Background

Hospital readmissions following transcatheter aortic valve replacement (TAVR) are associated with higher costs and worse outcomes.

Purpose

Identify causes and risk factors for readmissions after TAVR

Methods

Hospitalizations of adults aged ≥50, with aortic stenosis and undergoing elective TAVR between 2012 and 2016 in the National Readmission Database were analyzed. Multivariable generalized logistic regression, adjusting for age, sex, Charleson Comorbidity Index, primary insurance type, median household income, hospital type and size, were used to assess the effect of inpatient complications, length of stay (LOS), discharge disposition, and TAVR hospital volume on 30-day cardiovascular (CV) and non-cardiovascular (non-CV) readmission.

Results

Between January 2012 and November 2016, 56,858 weighted TAVR hospitalizations were included. The most common causes of readmissions after TAVR were heart failure (23%), infection (17%), gastrointestinal (11%), respiratory (8%), and “other” non-CV causes (8%). The adjusted odds of both CV and non-CV readmissions were significantly higher in patients with acute kidney injury, inpatient LOS ≥5 days, those discharged to skilled nursing facility (SNF) and those treated at medium volume compared with high volume hospitals, Table 1.

Conclusion

Heart failure is the most common cause of readmissions after TAVR. Inpatient incidence of acute kidney injury, as well as longer LOS, SNF discharge and lower hospital TAVR volume were associated with higher odds of 30-day readmissions.

Funding Acknowledgement

Type of funding source: None

Immunotoxicological effects of dioxin-like polychlorinated biphenyls extracted from Zhanjiang Bay sediments in zebrafish

Dioxin-like polychlorinated biphenyls (DLPCBs) are ubiquitous environmental contaminants spread all over the world. They can cause disorders in the reproductive, nervous, gut, and immune systems. We investigated the effects of DL-PCB extracted from Zhanjiang (Guangdong Province, China) offshore area on the immune functions of adult zebrafish. Zebrafish were exposed to different levels of DL-PCBs, i.e., control, positive control (PCB77 at 16.0 μg/L), low (LD; PCB81 + PCB118 at 0.32 μg/L), and high-dose (HD; PCB81 + PCB118 at 16.0 μg/L) groups for 28 days. Compared with the control group, positive control and HD group showed a significant decrease (P < 0.05) in the number of red blood cells (RBC) on day 7 and the same decrease was observed in the LD group (P < 0.05) on day 21. The results of white blood cell (WBC) profiles were opposite to that of RBCs. Moreover, the serum lysozyme activity was significantly lower in positive control and HD group (P < 0.05) on day 21 but no significant effect was observed in the LD group. The mucus lysozyme activity and immunoglobulin concentration in positive control and HD group decreased significantly (P < 0.05) from day 14. A similar effect was observed in the LD group but was significant (P < 0.05) only on day 28. Additionally, histopathological examination showed accumulation of hemosiderin in the spleen of experimental animals, which was significant in positive control and HD group. Further, renal tubular epithelial cells of head kidney were swollen in the positive control and HD group while the expansion of lumen and renal interstitial edema was observed in the LD group on day 21 and with significant presence on 28 days. Therefore, these findings suggest that the exposure of zebrafish to DL-PCBs at > 16.0 μg/L can impair their immune functions.

P57262018 ESC/ESH guideline-recommended age categories and intensive blood pressure management in high-risk adults: insights from SPRINT

Background

The 2018 European Society of Cardiology/European Society of Hypertension (ESC/ESH) guidelines for arterial hypertension propose different intensities of blood pressure (BP) lowering in patients <65 years, 65–79 years, and ≥80 years of age. However, it is unclear whether intensive BP management is well-tolerated and modifies risk uniformly across this age spectrum.

Purpose

To assess the relationship between age, treatment response to intensive BP lowering, and cardiovascular (CV) outcomes.

Methods

SPRINT was a randomized, controlled trial in which 9,361 individuals ≥50 years of age, at high CV risk but without diabetes who had a systolic BP (SBP) 130–180 mmHg, were randomized to intensive (target SBP <120mmHg) or standard antihypertensive treatment (target SBP <140mmHg). The primary efficacy endpoint was the composite of acute coronary syndromes, stroke, heart failure, or death from CV causes. The primary safety endpoint was the composite of serious adverse events (SAE). We examined the prognostic implications of age, using Cox proportional-hazards regression models adjusted for demographic, clinical, and laboratory variables. Whether a linear association was present between age and clinical endpoints was evaluated using restricted cubic splines. We further explored the effects of intensive BP lowering across the age spectrum using interaction analyses.

Results

Age was noted for all individuals, and 3,805 (41%), 4,390 (47%), and 1,166 (12%) were <65 years, 65–79 years, and ≥80 years, respectively. Mean age was similar between the two study groups (intensive group 67.9 years vs. standard group 67.9 years; P=0.94). Median follow-up was 3.3 years (range 0–4.8), with 562 primary efficacy events (6%) and 3,529 primary safety events (38%) recorded during the study period. Age was linearly associated with the risk of stroke (test for overall trend, P<0.001) and non-linearly associated with the risk of primary efficacy events, death from CV causes, death from any cause, heart failure, and SAE (test for non-linearity, P<0.05; test for overall trend, P<0.001). Age remained significantly associated with all tested endpoints after multivariable adjustment (P<0.001). Furthermore, the risk of primary events increased over guideline-recommended age-categories (65–79 years vs. <65 years; adj. HR 1.65, 95% CI 1.34–2.04; P<0.001 and ≥80 years vs. 65–79 years; adj. HR 1.92, 95% CI 1.54–2.40; P<0.001), as did the risk of SAE (P<0.001). The safety and efficacy of intensive BP lowering was not modified by age whether tested continuously or categorically (P>0.05). The Figure shows similar treatment effects (hazard ratios) across the spectrum of age. P-values are for the interaction between age and treatment effect for each endpoint.

Figure 1

Conclusions

In SPRINT, higher age was associated with a greater risk of both CV events and SAE. However, intensive BP lowering appeared to be associated with similar risks and benefits across the age spectrum.

Effects of Starvation and Thermal Stress on the Thermal Tolerance of Silkworm, Bombyx mori: Existence of Trade-offs and Cross-Tolerances

Organisms, in nature, are often subjected to multiple stressors, both biotic and abiotic. Temperature and starvation are among the main stressors experienced by organisms in their developmental cycle and the responses to these stressors may share signaling pathways, which affects the way these responses are manifested. Temperature is a major factor governing the performance of ectothermic organisms in ecosystems worldwide and, therefore, the thermal tolerance is a central issue in the thermobiology of these organisms. Here, we investigated the effects of starvation as well as mild heat and cold shocks on the thermal tolerance of the larvae of silkworm, Bombyx mori (Linnaeus). Starvation acted as a meaningful or positive stressor as it improved cold tolerance, measured as chill coma recovery time (CCRT), but, at the same time, it acted as a negative stressor and impaired the heat tolerance, measured as heat knockdown time (HKT). In the case of heat tolerance, starvation negated the positive effects of both mild cold as well as mild heat shocks and thus indicated the existence of trade-off between these stressors. Both mild heat and cold shocks improved the thermal tolerance, but the effects were more prominent when the indices were measured in response to a stressor of same type, i.e., a mild cold shock improved the cold tolerance more than the heat tolerance and vice versa. This improvement in thermal tolerance by both mild heat as well as cold shocks indicated the possibility of cross-tolerance between these stressors.

Long term outcomes in 46, XX adult patients with congenital adrenal hyperplasia reared as males

Patients with Congenital Adrenal Hyperplasia (CAH) owing to 21-hydroxylase deficiency and whose karyotype is 46, XX are usually assigned to the female gender. Reported herein are the long term outcomes in three patients with CAH whose karyotype is 46, XX and who were reared as males. A retrospective review of three CAH patients with a 46, XX karyotype who were reared as males was conducted. Gender assignment, clinical and biochemical data, pre and post-genitoplasty genital examinations were reviewed. Gender identity was tested by an extensive questionnaire. Gender role, sexual preference, marital status and sexual satisfaction were evaluated by interview. The three patients were genotyped for the CYP21A2 gene confirming the diagnosis of CAH. Owing to genital virilization, cultural preferences for male gender and the lack of newborn screening programs the three patients reported herein were assigned to the male gender at birth before the diagnosis of CAH was established. In adulthood the patients remained significantly virilized. Thorough psychosexual assessments in adulthood revealed well established male gender identities compatible with their male gender assignments at birth. In all three patients, gender role and behavior were consistent with male gender identity including sexual intercourse with female partners. The three patients reported herein revealed that male gender assignment to CAH patients with a 46, XX karyotype may have a successful outcome providing there is strong parental support and expert endocrine care. No standard guidelines have been published for the gender assignment of CAH patients with a 46, XX karyotype and genital ambiguity. More studies concerning gender assignment in CAH patients with a 46, XX karyotype reared as males are needed.

Antimicrobial resistance in Salmonella enterica serovar typhi and paratyphi in South Asia-current status, issues and prospects

The human race owes a debt of gratitude to antimicrobial agents, penicillin and its successors that have saved people from tremendous pain and suffering in the last several decades. Unfortunately, this consideration is no more true, as millions of people are prone to the challenging threat of emergence of antimicrobial resistance worldwide and the menace is more distressing in developing countries. Comparable with other bacterial species, Salmonella enterica serovar Typhi (S. typhi) and Paratyphi (S. paratyphi) have been evolving multidrug resistance (MDR) against a wide array of antibiotics, including chloramphenicol, ampicillin and co-trimoxazole, and globally affecting 21 million people with 220,000 deaths each year. S. typhi and S. paratyphi infections are also endemic in South Asia and a series of antibiotics used to treat these infections, have been losing efficacy against enteric fever. Currently, quinolones are regarded as a choice to treat MDR Salmonella in these regions. Travel-related cases of enteric fever, especially from South Asian countries are the harbinger of the magnitude of MDR Salmonella in that region. Conclusively, the MDR will continue to grow and the available antimicrobial agents would become obsolete. Therefore, a radical and aggressive approach in terms of rational use of antibiotics during treating infections is essentially needed.

Fractures of the distal third of the clavicle treated by hook plating

We retrospectively assessed the union and shoulder function following hook plate fixation in 18 patients with Neer type 2 fractures of the lateral end of the clavicle. The average age was 40 (range 22-62) years, and the mean follow-up was 25 (range 6-48) months. Fifteen patients had acute fractures and the rest were non-unions. Complications included two non-unions, one following a deep infection. There were no iatrogenic fractures. Acromial osteolysis was seen in five patients who had their plates in situ. The average pain score at rest was 1 (range 0-4), and the average pain score on abduction was 2.2 (range 0-5). The average Constant score was 88.5 (range 63-100). Patients were asked to rate their shoulder function; three rated it as normal, 11 as nearly normal and one as not normal. Hook plate fixation appears to be a valuable method of stabilising Neer type 2 fractures of the clavicle, resulting in high union rates and good shoulder function. These plates need to be removed after union to prevent acromial osteolysis.

Saccharomyces boulardii stimulates intestinal immunoglobulin A immune response to Clostridium difficile toxin A in mice

Saccharomyces boulardii is a nonpathogenic yeast that protects against antibiotic-associated diarrhea and recurrent Clostridium difficile colitis. The administration of C. difficile toxoid A by gavage to S. boulardii-fed BALB/c mice caused a 1.8-fold increase in total small intestinal immunoglobulin A levels (P = 0.003) and a 4.4-fold increase in specific intestinal anti-toxin A levels (P < 0.001). Enhancing host intestinal immune responses may be an important mechanism for S. boulardii-mediated protection against diarrheal illnesses.

Association between antibody response to toxin A and protection against recurrent Clostridium difficile diarrhoea

BACKGROUND

We have reported that symptom-free carriers of Clostridium difficile have a systemic anamnestic immune response to toxin A. The aim of this study was to determine whether an acquired immune response to toxin A, during an episode of C. difficile diarrhoea, influences risk of recurrence.

METHODS

We prospectively studied 63 patients with nosocomial C. difficile diarrhoea. Serial serum IgA, IgG, and IgM concentrations against C. difficile toxin A, toxin B, or non-toxin antigens were measured by ELISA. Individuals were followed for 60 days.

FINDINGS

19 patients died (30%). Of the 44 who survived, 22 had recurrent C. difficile diarrhoea. Patients with a single episode of C. difficile diarrhoea (n=22) had higher concentrations of serum IgM against toxin A on day 3 of their first episode of diarrhoea than those with recurrent diarrhoea (n=22, p=0.004). On day 12, serum IgG values against toxin A were higher in patients who had a single episode of diarrhoea (n=7) than in those who subsequently had recurrent diarrhoea (n=9, p=0.009). The odds ratio for recurrence associated with a low concentration of serum IgG against toxin A, measured 12 days after onset of C. difficile diarrhoea, was 48.0 (95% CI 3.5-663).

INTERPRETATION

A serum antibody response to toxin A, during an initial episode of C. difficile diarrhoea, is associated with protection against recurrence.

p38 MAP kinase activation by Clostridium difficile toxin A mediates monocyte necrosis, IL-8 production, and enteritis

Clostridium difficile toxin A causes acute neutrophil infiltration and intestinal mucosal injury. In cultured cells, toxin A inactivates Rho proteins by monoglucosylation. In monocytes, toxin A induces IL-8 production and necrosis by unknown mechanisms. We investigated the role of mitogen-activated protein (MAP) kinases in these events. In THP-1 monocytic cells, toxin A activated the 3 main MAP kinase cascades within 1 to 2 minutes. Activation of p38 was sustained, whereas stimulation of extracellular signal-regulated kinases and c-Jun NH(2)-terminal kinase was transient. Rho glucosylation became evident after 15 minutes. IL-8 gene expression was reduced by 70% by the MEK inhibitor PD98059 and abrogated by the p38 inhibitor SB203580 or by overexpression of dominant-negative mutants of the p38-activating kinases MKK3 and MKK6. SB203580 also blocked monocyte necrosis and IL-1beta release caused by toxin A but not by other toxins. Finally, in mouse ileum, SB203580 prevented toxin A-induced neutrophil recruitment by 92% and villous destruction by 90%. Thus, in monocytes exposed to toxin A, MAP kinase activation appears to precede Rho glucosylation and is required for IL-8 transcription and cell necrosis. p38 MAP kinase also mediates intestinal inflammation and mucosal damage induced by toxin A.

Asymptomatic carriage of Clostridium difficile and serum levels of IgG antibody against toxin A

BACKGROUND

Clostridium difficile infection can result in asymptomatic carriage, mild diarrhea, or fulminant pseudomembranous colitis. We studied whether antibody responses to C. difficile toxins affect the risks of colonization, diarrhea, and asymptomatic carriage.

METHODS

We prospectively studied C. difficile infections in hospitalized patients who were receiving antibiotics. Serial stool samples were tested for C. difficile colonization by cytotoxin assay and culture. Serum antibody (IgA, IgG, and IgM) levels and fecal antibody (IgA and IgG) levels against C. difficile toxin A, toxin B, and nontoxin antigens were measured by an enzyme-linked immunosorbent assay (ELISA).

RESULTS

Of 271 patients, 37 (14 percent) were colonized with C. difficile at the time of admission, 18 of whom were asymptomatic carriers. An additional 47 patients (17 percent) became infected in the hospital, 19 of whom remained asymptomatic. The baseline antibody levels were similar in the patients who later became colonized and those who did not. After colonization, those who became asymptomatic carriers had significantly greater increases in serum levels of IgG antibody against toxin A than did the patients in whom C. difficile diarrhea developed (P<0.001). The adjusted odds ratio for diarrhea was 48.0 (95 percent confidence interval, 3.4 to 678) among patients with colonization who had a serum level of IgG antibody against toxin A of 3.00 ELISA units or less, as compared with patients with colonization who had a level of more than 3.00 ELISA units.

CONCLUSIONS

We find no evidence of immune protection against colonization by C. difficile. However, after colonization there is an association between a systemic anamnestic response to toxin A, as evidenced by increased serum levels of IgG antibody against toxin A, and asymptomatic carriage of C. difficile.

The Goldman algorithm revisited: prospective evaluation of a computer-derived algorithm versus unaided physician judgment in suspected acute myocardial infarction

BACKGROUND

It has been nearly a decade since Goldman's computer-driven algorithm to predict myocardial infarction was validated. Despite the potential to avoid admission of patients without acute myocardial infarction (AMI) to the coronary care unit (CCU), the routine use of computer-generated protocols has not been widely adopted.

METHODS

Two hundred consecutive patients admitted to a university-affiliated community hospital with the suspected diagnosis of AMI as determined by physicians without the aid of the Goldman protocol underwent a blinded prospective evaluation to assess the performance of the Goldman algorithm in predicting the presence of AMI. Over the same time period, the Goldman algorithm was applied by retrospective chart review in 762 patients with non-AMI admitting diagnoses. Prospective history, physical examination, and electrocardiographic data were obtained within 24 hours of admission to the CCU by a physician blinded to each patient's clinical course. Retrospective chart reviews were conducted for 762 patients with chest pain given with non-AMI diagnoses.

RESULTS

The diagnosis of AMI was confirmed in 68.5% (137/200) of patients with suspected AMI admitted to the CCU. In prospective parallel evaluations the Goldman algorithm predicted the presence of AMI in 167 (83.5%) of these 200 patients. All 137 confirmed patients with AMI were correctly identified by the Goldman algorithm. All major in-hospital complications occurred in the 137 patients who were diagnosed as having AMI. Of the 762 patients with chest pain with non-AMI diagnoses, only 27 (3.5%) sustained an AMI. The Goldman algorithm predicted the presence of AMI in 85% (23/27) of these patients. Adherence to the use of Goldman's algorithm in the triage of chest pain could have prevented 16.5% of CCU admissions for AMI.

CONCLUSIONS

Routine adherence to the Goldman algorithm for the evaluation of patients with acute chest pain could have decreased the number of CCU admissions for suspected AMI by 16. 5%. Because major in-hospital complications occurred only in patients with AMI, this strategy would result in significant cost savings to our health care system without jeopardizing patient safety.

Diagnosis of myocardial infarction: integration of serum markers and clinical descriptors using information theory

OBJECTIVE

We examine the use of information theory applied to a single cardiac troponin T (cTnT) (first generation monoclonal; Boehringer Mannheim Corp., Indianapolis, Indiana) used with the character of chest pain, electrocardiography (ECG) and serial ECG changes in the evaluation of acute myocardial infarction (AMI). We combined a single measure of cTnT (blinded to the investigators) with a creatine kinase MB isoenzyme (CK-MB) measurement to discover the best decision value for this test in a study of 293 consecutive patients presenting to the emergency department with symptoms warranting exclusion of AMI.

METHODS

The decision value for determining whether cTnT is positive or negative was determined independently of the final diagnosis by examining the information in the cTnT and CKMB data. Using information theory, an autocorrelation matrix with a one-to-one pairing of the CKMB and troponin T was constructed. The effective information, also known as Kullback entropy, assigned the values for troponin T and for CKMB that have the lowest frequency of misclassification error. The Kullback entropy is determined by subtracting the data entropy from the maximum entropy of the data set in which the information has been destroyed. The assignment of the optimum decision values was made independently of the clinical diagnoses without the construction of a receiver-operator characteristic curve (ROC). The final diagnosis of AMI was independently determined by the clinicians and entered into the medical record.

RESULTS

The decision value for cTnT was 0.1 ng/ml as determined by the the information in the data. The method was validated within the same study by mapping the results so obtained into the diagnoses obtained independently by the clinicians using all of the methods at their disposal. The cTnT was different in AMI (n = 60) compared with non-AMI patients (n = 233) (2.08 +/- 0.21 vs. 0.07 +/- 0.10; p < .0001).

CONCLUSION

Information theory provides a strong framework and methodology for determining the decision value for cTnT which minimizes misclassification errors at 0.1 ng/ml. The result has a strong correlation with other features in detecting AMI in patients presenting with chest pain.

Evaluating a new graphical ordinal logit method (GOLDminer) in the diagnosis of myocardial infarction utilizing clinical features and laboratory data

OBJECTIVE

We used a new graphical ordinal logit method (GOLDminer) to assess a single cardiac troponin T (cTnT) analysis at the time of admission (first generation monoclonal; Roche BMC Corp., Indianapolis, Indiana), the character of chest pain, and electrocardiographic (ECG)findings in predicting the likelihood of acute myocardial infarction (AMI) in patients presenting with suspected myocardial ischemia. The final diagnosis of AMI was based on serial ECG findings and evolution of CKMB isoenzyme levels in conjunction with clinical findings.

SUBJECTS

The study population consisted of 293 consecutive patients who presented at a mean of six hours after onset of chest pain or associated symptoms warranting a "rule-out" for AMI assessment to a university-affiliated community hospital.

RESULTS

The odds-ratio for an elevated cTnT (> 0. 1 ng/ml) in AMI was 22.2:1. There was an association between typical chest pain and cTnT (chi square = 78.23, p < .0001) and between abnormal ECG findings and cTnT (chi square = 108, p < .0001). The cTnT yielded diagnostic benefit in addition to chest pain characteristics and ECG findings in AMI. We present the odds-ratios for the combined features in GOLDminer plots.

CONCLUSION

We demonstrate how the odds-ratios for AMI are obtained after scaling continuous to ordinal the values for a single cTnT determination alone and with other features in patients presenting with chest pain.

Myocardial infarction in critically ill patients presenting with gastrointestinal hemorrhage: retrospective analysis of risks and outcomes

OBJECTIVES

To determine the frequency of and risk factors for myocardial infarction (MI) in patients admitted to an ICU with GI hemorrhage, and the effects of MI on mortality and length of stay.

METHODS

A retrospective review of the medical records of patients admitted to our ICU with GI hemorrhage was conducted. Charts were reviewed for various demographic, laboratory, and outcome parameters. Patients were categorized as having MI, not having MI, or inadequate data to allow classification.

RESULTS

Two hundred thirty admissions to the ICU for GI hemorrhage were reviewed. One hundred thirteen cases had serial creatine phosphokinase (CK) measurements with isoenzymes allowing diagnosis of MI. In these 113 cases, patients' mean age was 67.4+/-1.3 years and the mean APACHE II (acute physiology and chronic health evaluation) score was 10.9+/-0.6. The in-hospital mortality rate was 13/113 (11.5%). Patients who did not survive had a higher admission APACHE II score (15.8+/-2.0 vs 10.2+/-0.5; p = 0.02), lower initial systolic BP (104.5+/-4.4 vs 121.2+/-3.2 mm Hg; p = 0.005), and a longer length of ICU stay (8.3+/-1.8 vs 4.0+/-0.4 days; p = 0.04) than those who survived. Sixteen of 113 patients met enzymatic and ECG criteria for MI. One patient complained of chest pain and nine of 16 had shortness of breath and/or dizziness. Patients with MI had significantly more cardiac risk factors (2.4+/-0.2 vs 1.6+/-0.1; p = 0.006), lower presenting hematocrit (26.0+/-1.3 vs 30.5+/-0.8; p = 0.007), and lower lowest hematocrit in the first 48 h (22.3+/-0.9 vs 25.1+/-0.6; p = 0.01), and tended to have a longer ICU stays (7.9+/-2.2 vs 4.0+/-0.4 days; p = 0.09) than those without MI. Patients who had MI were not more likely to die during hospitalization (risk ratio = 1.8; 95% confidence interval, 0.6 to 5.8).

CONCLUSIONS

Myocardial infarction occurs frequently in patients admitted to intensive care with GI hemorrhage. A clinical history of and multiple risk factors for coronary artery disease may help identify patients who are at increased risk of MI, which tends to be associated with a higher acuity of illness and in-hospital mortality. Prospective studies are required to further substantiate these associations.

Outcomes research is the fifth discipline of the fifth generation of managed care: utility of a single troponin-T

OBJECTIVE

The fifth generation of managed care is disease management. Diseases have measurable risk in providing laboratory and medical services. The link between managing services and managing risk can be aided by leveraging the laboratory. We wish to remodel laboratory services to fit the needs of the use, thereby using the laboratory for competitive advantage by redesigning a desired output using a formal structured process. Outcomes research is the systems framework for the remodeling process through the link of laboratory output to clinical and financial outcomes. A process redesign model connects the use of laboratory tests to improved medical services by leveraging resources to achieve measurable improvement over current results. This view of outcomes research seeks both competitive advantage and measurable improvements in quality.

METHODOLOGY

This approach is illustrated by the patient presenting with chest pain (CP). A majority of the patients rule out for acute myocardial infarction (AMI), including patients with indigestion, shortness of breath, and other clinical findings. This is the basis for an emergency department (ED) CP observation unit to reduce coronary care unit admission rates. When the Goldman algorithm for discharging low-risk patients with CP from the ED using only clinical features and electrocardiographic findings proved difficult to implement, we turned to measuring the diagnostic efficiency of a new cardiac marker to replace the evolutionary changes in creatine kinase (CK) isoenzyme MB. The physicians making the decision were blinded to the results of the study. We fitted the expected characteristics of the test to the expected results for our program. The test was done on the presenting specimen of 293 evaluable patients with a median of 6.5 hours from the time of onset of CP to the time the specimen was drawn. The result was compared with the evolutionary pattern of CK-MB.

RESULTS

The sensitivity of the test at presentation to the ED was 85% compared with < 50% for the presenting CK-MB, the false negative results taken earlier than 3 hours or 10 days after the onset of symptoms. Troponin-T effectively identifies non Q-wave AMI much earlier than the CK-MB. This study led to a prospective randomized clinical trial to demonstrate an improved medical and financial benefit from an early rule in or rule out of severe coronary artery ischemia.

CONCLUSION

The study supports our hypothesis that the laboratory can systematically redesign its technology strategy and participate in the construction of a clinical pathway for the discharge from ED or admitting decisions with a test 98% sensitive for identifying patients with serious coronary ischemia by 3.5 hours after the onset of symptoms.

Effective resource management using a clinical and laboratory algorithm for chest pain triage

BACKGROUND

Bridgeport Hospital recently compared the use of a clinical algorithm with unaided physicians for the triage of 200 emergency department (ED) patients with chest pain for coronary care unit (CCU) admission.

HYPOTHESIS

Cardiac troponin-T may be an effective adjunct to an established clinical algorithm for accurate selection of patients who are admitted to the CCU for suspected acute myocardial infarction (AMI). It is elevated 6 hours earlier than lactate dehydrogenase fraction 1 (LD1) and may be the most effective test for confirming non Q-wave AMI (usually with ST-T changes and LD1/lactase dehydrogenase > 35%). It is elevated in class 3 angina with a high risk of fatal arrhythmia.

STUDY DESIGN

Clinical and electrocardiogram criteria for triage are as defined by Goldman et al. (see references 6 and 11). The exclusion of non-AMI within 4 hours of ED visit using troponin-T (or an alternative test) should allow more rapid treatment of non-AMI patients at a lower intensity of hospital service (e.g., telemetry versus ICU). This should translate into shorter length of stay for non-AMI patients and facilitate thrombolytic therapy with significant resultant medical and cost benefits.

LABORATORY DATA

Creatine kinase and its MB isoenzyme (CK-MB) are measured at the time of clinical triage and 4, 8, and 12 hours later. LD1 and total lactase dehydrogenase are measured 12 hours after initial sampling. Cardiac troponin-T is measured at the time of ED arrival and 4 hours later. ANALYSIS OF BENEFIT: The first thing to consider is reducing the cost from stress thalliums for low risk evaluation. The second is the evaluation of active ischemia--unstable angina and diagnosis of missed AMI. The Goldman algorithm eliminates unnecessary admissions to the CCU for chest pain, including unstable angina. There is a difference between AMI and triage for CCU admission (200 patients). CK-MBs allowed for the elimination of 37 non-AMIs. However, we missed eight cases of AMI that would have been LD1 positive (troponin positive) and gained 10 cases of unstable angina that should have been assigned to CCU or a monitored bed. Troponin found six more cases of unstable angina that were CK-MB negative but should have been class 3 unstable angina that could be assigned to at least a telemetry bed. This makes 14 cases of AMI or unstable angina unaccounted for by CK-MB (5.6%). All of the cases were at risk of ventricular arrhythmia within 36 hours. The only question was whether to assign them to CCU or to monitored beds. The third point in the analysis is to examine the savings in operating costs by substitution. The cost model, in selecting a strategy, takes test costs, clinical outcomes, and the cost of clinical algorithms into consideration.

An outbreak of enterically transmitted non-A, non-B hepatitis in Pakistan

An epidemic of enterically transmitted non-A, non-B hepatitis occurred at a college in Sargodha, Pakistan in early 1987. There were 133 clinical cases, an attack rate of approximately 20%. Though the disease was relatively mild, all clinical cases required hospitalization and prolonged convalescence. Nearly all cases were associated with a single water source. The epidemic ended when the water supply was improved. This is the 4th described epidemic of non-A, non-B hepatitis in Pakistan.

A Comparison of Thermal Observations of Mount St. Helens Before and During the First Week of the Initial 1980 Eruption

Before and during the first week of the March-April 1980 eruptions of Mount St. Helens, Washington, infrared thermal surveys were conducted to monitor the thermal activity of the volcano. The purpose was to determine if an increase in thermal activity had taken place since an earlier airborne survey in 1966. Nine months before the eruption there was no evidence of an increase in thermal activity. The survey during the first week of the 1980 eruptions indicated that little or no change in thermal activity had taken place up to 4 April. Temperatures of ejected ash and steam were low and never exceeded 15 degrees C directly above the vent.

Hydraulic Transients: A Seismic Source in Volcanoes and Glaciers

A source for certain low-frequency seismic waves is postulated in terms of the water hammer effect. The time-dependent displacement of a water-filled sub-glacial conduit is analyzed to demonstrate the nature of the source. Preliminary energy calculations and the observation of hydraulically generated seismic radiation from a dam indicate the plausibility of the proposed source.