0/1h-algorithm using a new high-sensitivity cardiac troponin I assay for early diagnosis of myocardial infarction

Background

The clinical performance of the novel high-sensitivity cardiac troponin I EXL (hs-cTnI-EXL) assay is unknown so far.

Purpose

We aimed to validate the clinical performance of the hs-cTnI-EXL assay and to derive and validate an hs-cTnI-EXL-specific 0/1h-algorithm for the early diagnosis of myocardial infarction (MI).

Methods

This multicenter study included patients presenting to the emergency department with symptoms suggestive of myocardial infarction. Central adjudication of final diagnoses was performed by two independent cardiologists using all clinical information including cardiac imaging twice: first, using serial hs-cTnI-Architect (primary analysis) and second, using serial hs-cTnT-Elecsys (secondary analysis) concentrations in addition to those clinically used (hs)-cTn. Hs-cTnI-EXL was measured at presentation and at 1h. The primary objective was to directly compare diagnostic accuracy quantified by the area under the receiver-operating-characteristic curve (AUC) of hs-cTnI-EXL, hs-cTnI-Architect and hs-cTnT-Elecsys. Secondary objectives included the derivation and validation of an hs-cTnI- EXL-specific 0/1h-algorithm.

Results

MI was the adjudicated final diagnosis in 204/1454 (14%) patients. At presentation, the AUC for hs-cTnI-EXL was 0.94 (95% CI, 0.93–0.96), being comparable to hs-cTnI-Architect (0.95; 95% CI, 0.93–0.96) and hs-cTnT-Elecsys (0.93; 95% CI, 0.91–0.95; Figure 1). In the derivation cohort (n=813), an optimal hs-cTnI-EXL-0/1h-algorithm was rule-out of MI with <9ng/L if onset of chest pain >3h or <9ng/L & 0h-1h-change <5ng/L, and rule-in with ≥160ng/L or 0h-1h-change ≥100ng/L. In the validation cohort (n=345), this hs-cTnI-EXL-0/1h-algorithm also performed well: rule-out in 56% of patients, negative predictive value 99.5% (95% CI, 97.1–99.9), sensitivity 97.8% (95% CI, 88.7–99.6), rule-in in 9% of patients, positive predictive value 83.3% (95% CI, 66.4–92.7), specificity 98.3% (95% CI, 96.1–99.3; Figure 2). Secondary analyses confirmed the findings using adjudication including serial measurements of hs-cTnT-Elecsys.

Conclusions

Hs-cTnI-EXL has comparable diagnostic performance to the currently best-validated hs-cTnT/I assays.

Funding Acknowledgement

Type of funding sources: Foundation. Main funding source(s): Swiss National Foundation, Swiss Heart Foundation

Associations of oral fluid MMP-8 with periodontitis in Swiss adult subjects

OBJECTIVE

MMP-8 is a prominent collagenase in periodontal disease. This cross-sectional study examined whether MMP-8 levels in saliva and gingival crevicular fluid (GCF) are associated with periodontitis in a Swiss population.

SUBJECTS AND METHODS

A total of 258 subjects (107 m, 151 f, mean age: 43.5 yr; range: 21-58 yr) acquired from the Swiss bone marrow donor registry participated in the study. Saliva and GCF samples were collected from subjects followed by a thorough dental and periodontal examination. MMP-8 levels were determined with immunofluorometric assay. Associations of MMP-8 levels with periodontal diagnosis, probing pocket depth (PPD) and bleeding on probing were statistically analysed with Pearson chi-square test, Spearman's rho and logistic regression analysis.

RESULTS

MMP-8 in GCF correlated with MMP-8 in saliva (p < .001). Periodontitis was more common (p < .001) among subjects with high levels of MMP-8 in saliva and/or GCF compared with subjects with low levels of MMP-8. Higher MMP-8 levels in GCF and saliva were associated with any periodontal diagnosis (mild, moderate or severe), greater PPD, and bleeding on probing (p < .05). When age, gender, smoking, body mass index, number of medications and decayed, missing and filled teeth were adjusted for, all observed associations remained statistically significant. The area under curve of receiver-operating characteristic was 0.67 for saliva and 0.71 for GCF.

CONCLUSION

Elevated MMP-8 levels both in saliva and GCF are associated with periodontitis in a normal adult population.

Numerical impairment of nestin(+) bone marrow niches in acute GvHD after allogeneic hematopoietic stem cell transplantation for AML

The nestin(+) perivascular bone marrow (BM) stem cell niche (N(+)SCN) may be involved in GvHD. To investigate whether acute GvHD (aGvHD) reduces the number of N(+)SCN, we examined patients with AML who had undergone allogeneic hematopoietic stem cell transplantation. In the test cohort (n=8), the number of N(+)SCN per mm(2) in BM biopsies was significantly reduced in aGvHD patients at the time of aGvHD compared with patients who did not have aGvHD (1.2±0.78 versus 2.6±0.93, P=0.04). In the validation cohort (n=40), the number of N(+)SCN was reduced (1.9±0.99 versus 2.6±0.90 N(+)SCN/mm(2), P=0.05) in aGvHD patients. Receiver operating curves suggested that the cutoff score that best discriminated between patients with and without aGvHD was 2.29 N(+)SCN/mm(2). Applying this cutoff score, 9/11 patients with clinically relevant aGvHD (⩾grade 2) and 13/20 with any type of GvHD had decreased N(+)SCN numbers compared with only 10/29 patients without clinically relevant aGvHD (P=0.007) and 6/20 patients without any type of GvHD (P=0.028). In patients tracked over time, N(+)SCN density returned to normal after aGvHD resolved or remained stable in patients who did not have aGvHD. Our results show a decrease in the number of N(+)SCN in aGvHD.

The Expression Pattern of CD56 (N-CAM) in Human Bone Marrow Biopsies Infiltrated by Acute Leukemia

In hematological neoplasms CD56 (N-CAM) is expressed by T/natural killer (NK) cell lymphoma, by most neoplastic plasma cells in multiple myeloma and also in a subset of acute myelogenous leukemias (AML). In the latter, it is an indicator of poor clinical outcome. Most of the data on CD56 expression in acute leukemia have been obtained by flow cytometric analysis. Up to now, no systematic analysis of the expression pattern of CD56 in formalin fixed paraffin embedded bone marrow biopsies of acute leukemias has been performed. We immunohistochemically studied the expression of CD56 in a series of 141 bone marrow biopsies fixed in Sublimat Mercury II Chloride (SUSA) including 100 cases of AML FAB M0-M7, 11 cases of AML not further specified, 3 cases of biphenotypical leukemia, 20 cases of acute lymphoblastic leukemia (ALL) and 7 cases of reactive bone marrow biopsies. Overall, 14 of 134 (10%) leukemia cases were positive for CD56. Detail analysis revealed positivity in 5/13 cases of AML M5 (38%), 3/9 AML M1 (33%), 1/8 AML M0 (13%), 1/11 AML not specified (9%), 2/31 AML M2 (7%) and 2/26 AML M4 (8%). All cases of ALL and biphenotypic leukemias were CD56 negative. The CD56 expression in AML M5 was statistically significant (p = 0.003). On paraffin embedded bone marrow biopsies CD56 expression occurs in de novo AML with an overall frequency of 13%. It is significantly correlated with AML M5, which is positive in 38% of the cases. Cases of ALL are consistently CD56 negative.

A pilot iron substitution programme in female blood donors with iron deficiency without anaemia

BACKGROUND AND OBJECTIVES

Blood donation can contribute to iron deficiency. The possibly resulting anaemia importantly affects donor return rate. The determination of serum ferritin levels revealed iron deficiency in many non-anaemic premenopausal female blood donors at our Institution. We started an iron substitution programme targeting this donor group to prevent anaemia and enhance donor retain.

MATERIALS AND METHODS

Women aged≤50 with haemoglobin levels adequate for donation and serum ferritin≤10 ng/ml were offered iron supplementation. Substitution lasted 16 weeks and the donation interval was extended. History collection including iron deficiency-related symptoms, whole blood count and serum ferritin determination was performed at baseline and after 2 and 6 months. Data were recorded prospectively and compared with those of 108 female controls with iron deficiency not receiving iron substitution (retrospective data).

RESULTS

Of the 116 participating subjects, 60% completed the programme. Significant results were serum ferritin increase (from a mean value of 7.12 to 25.2 ng/ml), resolution of prostration, fatigue, sleep disturbances, tension in the neck, hair loss and nail breakage. No case of anaemia occurred. Sixty per cent of the women completed the programme and donated blood again.

CONCLUSIONS

Targeted iron substitution prevents the development of anaemia and enhances donation return in premenopausal female blood donors with iron deficiency.

Transplant-associated microangiopathy (TAM) in recipients of allogeneic hematopoietic stem cell transplants

We studied occurrence, risk factors and outcome of patients with transplant-associated microangiopathy (TAM) after allogeneic stem cell transplantation (HSCT). A total of 221 consecutive patients were transplanted between 1995 and 2002. TAM is defined as evidence of hemolysis and schistocytes in the first 100 days. Outcomes analyzed included TAM and overall survival. Of 221 patients, 68 had TAM. The cumulative incidence was 31 (25-38)% at 100 days. Patients with TAM had higher LDH, higher bilirubin, higher creatinine and more often neurologic symptoms. TAM was not associated with stem cell source, cyclosporine levels and was not more frequent in recent years. In multivariate analysis, risk factors for TAM included donor type, age, gender, ABO-incompatibility and acute graft-versus-host disease (aGvHD). In patients with TAM, 1-year survival was lower than in patients without TAM (27 +/- 18% for TAM with high schistocyte counts; 53 +/- 15% for TAM with low schistocyte counts; vs 78 +/- 7% in patients without TAM; P<0.0001). TAM was independently associated with mortality adjusting for donor type, age and aGvHD occurrence and severity. TAM is frequent after HSCT and is associated with mortality even after adjustment for aGvHD grade. Risk factors of TAM are similar to aGvHD. TAM may represent endothelial damage driven by donor-host interactions.

Status febrilis mit Bewusstlosigkeit

Cerebral malaria with Plasmodium vivax is uncommon. Normally Plasmodium falciparum is the cause of cerebral malaria. We report about a 18 year old patient from Pakistan with a history of intermittent fever for several months. The patient recovered within a few days; however prognosis can be severe when cerebral malaria is complicating the course of Plasmodium vivax infection.

[Reduced visual capacity increases the risk of accidents in street traffic]

BACKGROUND

This study was carried out to investigate the relationship between the frequency of traffic accidents and impaired vision.

MATERIALS AND METHODS

Seven hundred and fifty-four drivers involved in accidents were recruited, in addition to 250 accident-free drivers similar in age and driving experience as an control group. The age distribution of the persons involved in traffic accidents (mean 56.3 years) was similar to that of the control group (mean 57.7 years), the difference was not statistically significant. Both groups underwent a complete ophthalmological examination.

RESULTS

All three types of accidents (night-time accidents, violations of right of way, accidents during an overtaking manoeuvre) had a statistically significantly higher incidence of reduced photopic visual acuity, mesopic vision and an increased sensitivity to glare. Some other visual functions were also abnormal, with differences according to the type of accident. In particular, there were noticeable differences between the control group and those who were involved in night-time accidents regarding mesopic vision and sensitivity to glare. Concerning mesopic vision, 15% of the 261 persons involved in night-time accidents did not reach the contrast limit of 1:5; with glare, 20.7% failed. In comparison 4% of the control group reached this critical limit without glare and 7.6% with glare. These differences are highly statistically significant. In contrast to these findings, many of the drivers involved in accidents assessed their own visual capability as "excellent".

CONCLUSIONS

The results of this study show that reduced mesopic vision and increased sensitivity to glare are accompanied by an increased risk of night-time accidents (for example, collisions with a non-illuminated obstacle). This emphasizes the importance of regular ophthalmological check-ups including visual functions such as mesopic vision and sensitivity to glare, which currently are not required by the traffic laws in Germany.

[Measuring saccades in endocrine orbitopathy]

Thyroid-associated ophthalmopathy (TAO) is evaluated mainly by orthoptic examination and morphometric parameters such as ultrasound, CT scanning or magnetic resonance imaging. Inflammatory changes of the extraocular muscles lead to an impairment of eye movement. Recent evidence suggests that saccades are altered by changes to the extraocular muscles. Although of potential interest, this phenomenon has so far received little attention. To determine the role of saccades as a potential diagnostic tool for assessing the function of the affected muscles, we have begun to analyze saccadic parameters in patients with TAO. Preliminary results of this study are reported in the present paper. For registration of both horizontal and vertical eye movements, we used the "Ober-2-Apparatus," which uses the infrared technique. Horizontal and vertical saccades with an amplitude of 10 degrees were analyzed in 20 healthy persons and 30 patients suffering from TAO. Patients showed changes in the quality of saccades, such as the appearance of glissades and additional correctional saccades as well as quantitative changes, such as an increase in the maximum speed and latency. Our current data suggest the presence of saccadic alterations in TAO. Our ongoing studies are designed to evaluate whether characteristic changes can be assigned to certain stages of the disease and whether assessment of saccadic changes in a promising tool for early detection and functional follow-up in patients with TAO.

[Effect of low alcohol concentrations on visual attention in street traffic]

There is currently public discussion as to whether the legal limit of blood alcohol concentration of drivers might be reduced from 0.8% to 0.5%. To acquire information concerning this problem, we measured temporal parameters of saccades and analysed the overall eye-movement behaviour with various blood ethanol concentrations. Eye movements were registered with an IR eye tracker and analysed while the subjects followed a randomly moving stimulus on a CRT screen and during presentation of a realistic traffic scene of 4 min duration on a TV screen. Alcohol has a significant effect on latency, velocity and accuracy of saccades, even at low concentrations between 0.4% and 0.6%. Because of the altered "gaze activity", the inflow of visual information is reduced in a state of inebriation. Our results are a further argument for reducing the legal limit of blood alcohol concentration to 0.5%.

[What visual information does the automobile driver need for safe driving in street traffic?]

In daytime traffic the driver experiences a tremendous input of visual information: His problem is to extract the relevant stimuli in order to have an adequate reaction. Traffic at dusk or nighttime, however, is characterized by the fact that even a driver with full visual function approaches his physiological limit. By assessing real traffic situations under various circumstances of weather and illumination (daytime, dusk, nighttime, city traffic, country road) limits of adaptation luminance, object size, object contrast and color are demonstrated. In addition, typical distributions of luminance in the visual field of the driver and the distributions of size and location of relevant objects are quantified. For glare situations typical values of glare angle and corneal illuminance of the glare light and the induced reduction of contrast are determined. Our data demonstrate the type of visual information required by the driver in order to drive safely in road traffic. These data allow conclusions to be made with respect to minimum requirements of visual function for car drivers.

[Limitation of lens power in automobile drivers]

High plus lenses may cause defects in the peripheral visual field. Simple full vision lenses or lenticular lenses without a masked transition zone caused an absolute ring scotoma in the mid-periphery. Patients who were glasses of this type cannot see well enough to drive safely. Although modern edge finishes with masking of the transition zone reduce this problem, visual disturbances in the periphery of the lenses cannot be completely eliminated. A recommendation recently issued by the German Ophthalmological Society concerning maximum lens powers for motorists is aimed at preventing visual field defects of this type.

Influence of stimulus size and contrast on the temporal parameters of saccadic eye movements: implications for road traffic

Saccadic eye movements are required for the recognition of peripheral objects in road traffic. Their latencies largely determine reaction time in emergency situations. The aim of this study was to investigate the influence of stimulus and surround parameters on the temporal characteristics of saccadic eye movements under conditions of object size, contrast and luminance corresponding to nighttime traffic. Square stimuli of 1 degree or 5 degrees size were presented under an eccentricity of 5 degrees and 15 degrees. The luminance of the surround was 4 x 10(-4) cd/m2 and 1 cd/m2. More than approx. 2,000 saccades of 7 normal subjects were registered and evaluated with respect to the latency, maximal velocity, and frequency of secondary saccades. At high stimulus contrast, latency approaches a minimum of approx. 200 ms. Latency increases with decreasing contrast up to maximal values of more than 600 ms. Transforming the contrast values into a relative decibel scale shows that this increase in latency occurs at significantly higher relative contrast values under scotopic as compared with photopic conditions. Our results demonstrate that an overall latency of 200-300 ms is not adequate for the assessment of accidents, especially under the stimulus conditions of nighttime traffic.