Unstable hemoglobin Montreal II uncovered in an adult with unexplained hemolysis exacerbated by a presumed viral infection: a case report.

BACKGROUND Unstable hemoglobinopathies are rare inherited disorders of hemoglobin causing a reduction of hemoglobin molecule solubility. This results in an unstable hemoglobin tetramer/globin polypeptide, which precipitates within the red blood cell. Affected red blood cells have a reduced lifespan due to oxidative stress and cellular rigidity, and tend to be phagocytized by spleen macrophages more rapidly. Unstable hemoglobin is frequently under- or misdiagnosed, because its clinical presentation varies broadly. Therefore, testing for unstable hemoglobinopathies is indicated in cases of unexplained hemolytic anemia. However, this approach is not systematically followed in clinical practice. CASE REPORT A 25-year-old Caucasian man with a recent history of a presumed viral upper respiratory infection was referred to the hematology outpatient clinic because of hemolytic anemia. The patient had scleral icterus, moderate splenomegaly, and mild macrocytic anemia with high reticulocyte count. Unconjugated bilirubin and lactate dehydrogenase were elevated. Haptoglobin was undetectable. Direct antiglobulin test was negative. Blood smear examination revealed anisopoikilocytosis, polychromasia, bite cells, and basophilic stippling, but no Heinz bodies. High-performance liquid chromatography and capillary electrophoresis showed slightly increased hemoglobin A2, normal fetal hemoglobin, and a variant hemoglobin. Deoxyribonucleic Acid sequencing revealed the heterozygous mutation c430delC in the beta-globin gene hallmark of hemoglobin Montreal II and the heterozygous mutation c287C>T in the alpha-globin gene corresponding to hemoglobin G-Georgia, indicative of the not yet described combination of double-heterozygous hemoglobin Montreal II and hemoglobin G-Georgia variants. Hemoglobinopathy Montreal II was here not associated with β-thalassemia syndrome, and carriers did not show ineffective erythropoiesis. In addition to the case report, we provide information about the largest pedigree with hemoglobinopathy Montreal II identified to date. CONCLUSION We emphasize that a transitory acute condition may uncover an underlying inherited red blood cell disorder. In this regard, awareness should be raised among hematologists caring for adult patients that unstable hemoglobinopathies should be considered in the differential diagnosis of unexplained hemolytic anemias

Clinical Utility of D-Dimer for Rule-Out or Rule-In of Venous Thromboembolism in Syncope

Fig. 1 Diagnostic performance of D-dimer using two different assays in patients presenting with syncope. A Left: Receiver-operating characteristic curves quantifying the diagnostic performance of Innovance® D-dimer (blue) and hs-Loci-Innovance® D-dimer (red) for the diagnosis of venous thromboembolism (VTE). Right: Clinical application of D-dimer using the 2-level Wells-score with age-adjusted1 or fixed cutoffs versus the YEARS-algorithm with probability-adjusted cut offs2. B Left: Specificity for different cufoffs of Innovance® D-dimer (blue) and hs-Loci-Innovance® D-dimer (red) for the diagnosis of venous thromboembolism (VTE). Right: Percentage of patients ruled-in and correctly identified VTE patients for different cutoffs of Innovance® D-dimer (blue) and hs-Loci-Innovance® D-dimer (red). 1In patients 50 years or younger, D-dimer concentration < 0.5 mg/l was considered negative. For patients older than 50 years, we used the formula: age in years divided by 100. 2YEARS-algorithm: assessment of only three items from the Wells-score (clinical signs of deep vein thrombosis, hemoptysis, pulmonary embolism the most likely diagnosis) and using a D-dimer test threshold of 0.5 mg/l in presence, and 1.0 mg/l in absence of one of the YEARS-items. Keywords: Diagnostic testing; Pulmonary embolism; Syncop

Exploring the host factors affecting asymptomatic Plasmodium falciparum infection: insights from a rural Burkina Faso study.

BACKGROUND Asymptomatic Plasmodium falciparum parasitaemia forms a reservoir for the transmission of malaria disease in West Africa. Certain haemoglobin variants are known to protect against severe malaria infection. However, data on the potential roles of haemoglobin variants and nongenetic factors in asymptomatic malaria infection is scarce and controversial. Therefore, this study investigated the associations of iron homeostasis, inflammation, nutrition, and haemoglobin mutations with parasitaemia in an asymptomatic cohort from a P. falciparum-endemic region during the high transmission season. METHODS A sub-study population of 688 asymptomatic individuals (predominantly children and adolescents under 15 years, n = 516) from rural Burkina Faso previously recruited by the NOVAC trial (NCT03176719) between June and October 2017 was analysed. Parasitaemia was quantified with conventional haemocytometry. The haemoglobin genotype was determined by reverse hybridization assays targeting a selection of 21 HBA and 22 HBB mutations. Demographics, inflammatory markers (interleukins 6 and 10, hepcidin), nutritional status (mid upper-arm circumference and body mass index), and anaemia (total haemoglobin, ferritin, soluble transferrin receptor) were assessed as potential predictors through logistic regression. RESULTS Malaria parasites were detected in 56% of subjects. Parasitaemia was associated most strongly with malnutrition. The effect size increased with malnutrition severity (OR = 6.26, CI95: 2.45-19.4, p < 0.001). Furthermore, statistically significant associations (p < 0.05) with age, cytokines, hepcidin and heterozygous haemoglobin S were observed. CONCLUSIONS According to these findings, asymptomatic parasitaemia is attenuated by haemoglobin S, but not by any of the other detected genotypes. Aside from evidence for slight iron imbalance, overall undernutrition was found to predict parasitaemia; thus, further investigations are required to elucidate causality and inform strategies for interventions

Biomarkers of Hemodynamic Stress and Aortic Stiffness after STEMI: A Cross-Sectional Analysis

Aim. Increased aortic stiffness might adversely affect cardiac structure, function, and perfusion. Release of biomarkers of hemodynamic stress is thought to be enhanced by these alterations. We aimed to evaluate the association between biomarkers of hemodynamic stress and aortic stiffness assessed at a chronic stage after ST-segment elevation myocardial infarction (STEMI). Methods. Fifty-four patients four months after STEMI were enrolled in this cross-sectional, single-center study. N-terminal pro-B-type natriuretic peptide (NT-proBNP), mid-regional pro-A-type natriuretic peptide (MR-proANP), and mid-regional proadrenomedullin (MR-proADM) levels were measured by established assays. Aortic stiffness was assessed by the measurement of pulse wave velocity using phase-contrast cardiovascular magnetic resonance. Results. NT-proBNP, MR-proANP, and MR-proADM concentrations were all correlated with aortic stiffness in univariate analysis ( = 0.378, = 0.425, and = 0.532; all &lt; 0.005, resp.). In multiple linear regression analysis, NT-proBNP ( = 0.316, = 0.005) and MR-proADM ( = 0.284, &lt; 0.020) levels were associated with increased aortic stiffness independently of age, blood pressure, and renal function. NT-proBNP was the strongest predictor for high aortic stiffness (area under the curve: 0.82, 95% CI 0.67-0.96). Conclusion. At a chronic stage after STEMI, concentrations of biomarkers for hemodynamic stress, especially NT-proBNP, are positively correlated with aortic stiffness. These biomarkers might also be useful as predictors of high aortic stiffness after STEMI

Diagnostic discrimination of a novel high-sensitivity cardiac troponin I assay and derivation/validation of an assay-specific 0/1h-algorithm

BACKGROUND We aimed to assess the diagnostic utility of the Dimension EXL LOCI High-Sensitivity Troponin I (hs-cTnI-EXL) assay. METHODS This multicenter study included patients with chest discomfort presenting to the emergency department. Diagnoses were centrally and independently adjudicated by two cardiologists using all available clinical information. Adjudication was performed twice including serial measurements of high-sensitivity cardiac troponin (hs-cTn) I-Architect (primary analysis) and serial measurements of hs-cTnT-Elecsys (secondary analysis) in addition to the clinically used (hs)-cTn. The primary objective was to assess and compare the discriminatory performance of hs-cTnI-EXL, hs-cTnI-Architect and hs-cTnT-Elecsys for acute myocardial infarction (MI). Furthermore, we derived and validated a hs-cTnI-EXL-specific 0/1h-algorithm. RESULTS Adjudicated MI was the diagnosis in 204/1454 (14%) patients. The area under the receiver operating characteristics curve for hs-cTnI-EXL was 0.94 (95%CI, 0.93-0.96), and 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). In the derivation cohort (n = 813), optimal criteria for rule-out of MI were 3h) or <9ng/L and 0h-1h-change <5ng/L, and for rule-in ≥160ng/L at presentation or 0h-1h-change ≥100ng/L. In the validation cohort (n = 345), these cut-offs ruled-out 56% of patients (negative predictive value 99.5% (95%CI, 97.1-99.9), sensitivity 97.8% (95%CI, 88.7-99.6)), and ruled-in 9% (positive predictive value 83.3% (95%CI, 66.4-92.7), specificity 98.3% (95%CI, 96.1-99.3)). Secondary analyses using adjudication based on hs-cTnT measurements confirmed the findings. CONCLUSIONS The overall performance of the hs-cTnI-EXL was comparable to best-validated hs-cTnT/I assays and an assay-specific 0/1h-algorithm safely rules out and accurately rules in acute MI. CLINICAL TRIAL REGISTRATION ClinicalTrials.gov number, NCT00470587

Perioperative Myocardial Injury After Non-cardiac Surgery: Incidence, Mortality, and Characterization

Perioperative myocardial injury (PMI) seems to be a contributor to mortality after noncardiac surgery. Because the vast majority of PMIs are asymptomatic, PMI usually is missed in the absence of systematic screening.; We performed a prospective diagnostic study enrolling consecutive patients undergoing noncardiac surgery who had a planned postoperative stay of ≥24 hours and were considered at increased cardiovascular risk. All patients received a systematic screening using serial measurements of high-sensitivity cardiac troponin T in clinical routine. PMI was defined as an absolute high-sensitivity cardiac troponin T increase of ≥14 ng/L from preoperative to postoperative measurements. Furthermore, mortality was compared among patients with PMI not fulfilling additional criteria (ischemic symptoms, new ECG changes, or imaging evidence of loss of viable myocardium) required for the diagnosis of spontaneous acute myocardial infarction versus those that did.; From 2014 to 2015 we included 2018 consecutive patients undergoing 2546 surgeries. Patients had a median age of 74 years and 42% were women. PMI occurred after 397 of 2546 surgeries (16%; 95% confidence interval, 14%-17%) and was accompanied by typical chest pain in 24 of 397 patients (6%) and any ischemic symptoms in 72 of 397 (18%). Crude 30-day mortality was 8.9% (95% confidence interval [CI], 5.7-12.0) in patients with PMI versus 1.5% (95% CI, 0.9-2.0) in patients without PMI (; P; &lt;0.001). Multivariable regression analysis showed an adjusted hazard ratio of 2.7 (95% CI, 1.5-4.8) for 30-day mortality. The difference was retained at 1 year with mortality rates of 22.5% (95% CI, 17.6-27.4) versus 9.3% (95% CI, 7.9-10.7). Thirty-day mortality was comparable among patients with PMI not fulfilling any other of the additional criteria required for spontaneous acute myocardial infarction (280/397, 71%) versus those with at least 1 additional criterion (10.4%; 95% CI, 6.7-15.7, versus 8.7%; 95% CI, 4.2-16.7;; P; =0.684).; PMI is a common complication after noncardiac surgery and, despite early detection during routine clinical screening, is associated with substantial short- and long-term mortality. Mortality seems comparable in patients with PMI not fulfilling any other of the additional criteria required for spontaneous acute myocardial infarction versus those patients who do.; URL: https://www.clinicaltrials.gov. Unique identifier: NCT02573532

Daytime variation of perioperative myocardial injury in non-cardiac surgery and effect on outcome

Recently, daytime variation in perioperative myocardial injury (PMI) has been observed in patients undergoing cardiac surgery. We aim at investigating whether daytime variation also occurs in patients undergoing non-cardiac surgery.; In a prospective diagnostic study, we evaluated the presence of daytime variation in PMI in patients at increased cardiovascular risk undergoing non-cardiac surgery, as well as its possible impact on the incidence of acute myocardial infarction (AMI), and death during 1-year follow-up in a propensity score-matched cohort. PMI was defined as an absolute increase in high-sensitivity cardiac troponin T (hs-cTnT) concentration of ≥14 ng/L from preoperative to postoperative measurements.; Of 1641 patients, propensity score matching defined 630 with similar baseline characteristics, half undergoing non-cardiac surgery in the morning (starting from 8:00 to 11:00) and half in the afternoon (starting from 14:00 to 17:00). There was no difference in PMI incidence between both groups (morning: 50, 15.8% (95% CI 12.3 to 20.3); afternoon: 52, 16.4% (95% CI 12.7 to 20.9), p=0.94), nor if analysing hs-cTnT release as a quantitative variable (median morning group: 3 ng/L (95% CI 1 to 7 ng/L); median afternoon group: 2 ng/L (95% CI 0 to 7 ng/L; p=0.16). During 1-year follow-up, the incidence of AMI was 1.2% (95% CI 0.4% to 3.2%) among morning surgeries versus 4.1% (95% CI 2.3% to 6.9%) among the afternoon surgeries (corrected HR for afternoon surgery 3.44, bootstrapped 95% CI 1.33 to 10.49, p log-rank=0.03), whereas no difference in mortality emerged (p=0.70).; Although there is no daytime variation in PMI in patients undergoing non-cardiac surgery, the incidence of AMI during follow-up is increased in afternoon surgeries and requires further study.; NCT02573532;Results

Daytime variation of perioperative myocardial injury in non-cardiac surgery and effect on outcome

Recently, daytime variation in perioperative myocardial injury (PMI) has been observed in patients undergoing cardiac surgery. We aim at investigating whether daytime variation also occurs in patients undergoing non-cardiac surgery.; In a prospective diagnostic study, we evaluated the presence of daytime variation in PMI in patients at increased cardiovascular risk undergoing non-cardiac surgery, as well as its possible impact on the incidence of acute myocardial infarction (AMI), and death during 1-year follow-up in a propensity score-matched cohort. PMI was defined as an absolute increase in high-sensitivity cardiac troponin T (hs-cTnT) concentration of ≥14 ng/L from preoperative to postoperative measurements.; Of 1641 patients, propensity score matching defined 630 with similar baseline characteristics, half undergoing non-cardiac surgery in the morning (starting from 8:00 to 11:00) and half in the afternoon (starting from 14:00 to 17:00). There was no difference in PMI incidence between both groups (morning: 50, 15.8% (95% CI 12.3 to 20.3); afternoon: 52, 16.4% (95% CI 12.7 to 20.9), p=0.94), nor if analysing hs-cTnT release as a quantitative variable (median morning group: 3 ng/L (95% CI 1 to 7 ng/L); median afternoon group: 2 ng/L (95% CI 0 to 7 ng/L; p=0.16). During 1-year follow-up, the incidence of AMI was 1.2% (95% CI 0.4% to 3.2%) among morning surgeries versus 4.1% (95% CI 2.3% to 6.9%) among the afternoon surgeries (corrected HR for afternoon surgery 3.44, bootstrapped 95% CI 1.33 to 10.49, p log-rank=0.03), whereas no difference in mortality emerged (p=0.70).; Although there is no daytime variation in PMI in patients undergoing non-cardiac surgery, the incidence of AMI during follow-up is increased in afternoon surgeries and requires further study.; NCT02573532;Results

Emerging biomarkers for cardiac arrhythmias

Cardiac arrhythmias are associated with substantial morbidity and mortality. Recent advances in the pathophysiological understanding of cardiac arrhythmia indicate that inflammation, fibrosis, and even autoimmune mechanisms could facilitate the development of arrhythmias by interfering either with fibroblast activation-related electrical remodeling or with the function of different cardiac ion channels, leading to the emerging concepts of autoimmune and inflammatory channelopathies. In this descriptive review, we considered recent data of the literature focusing on biomarkers reflecting the degree of inflammation, myocardial stretch, fibrosis and sustained B-cell activation as potential additional diagnostic, risk stratification tools and potential therapeutic targets in cardiac arrhythmia