Analysis of cryoproteins with a focus on cryofibrinogen: a study on 103 patients.

OBJECTIVES: Cryofibrinogen (CF) is an abnormal protein in plasma that precipitates at 4 °C and dissolves at 37 °C. Whilst serum cryoglobulins (CGs) analysis is common practice, CF investigation is rarely performed. This study aims to describe the testing methodology developed at our laboratory, potential pitfalls for all analytical phases, the distribution among hospital wards and clinical conditions underlying test requests and clinical conditions in which to order CF analysis is useful. METHODS: Retrospective analysis of laboratory samples received between January 2019 and June 2021 with CF testing requests. RESULTS: A complete protocol for CF pre-analytical, analytical and post-analytical phases are supplied. Most test requests were received from the rheumatology department for systemic sclerosis or liver transplant screening. Among the 103 in-patients included, CF+ was confirmed in 68 patients (66%). Of observed CF+ patients (n=68) most cases were CGs- (n=44, 67%). Isolated CF was found in 43% of the cases. Among CF- patients (n=35; 34%) only 2 patients had positive CGs (CGs+). Among rheumatology patients (n=66), isolated CF+ was observed in 45% (n=30/66), whilst among patients with systemic sclerosis with CF+ (n=19), isolated CF+ was detected in 79% (n=15/19). CONCLUSIONS: Described analytical procedures may be used for the creation of harmonized recommendations and indications for CF analysis. Isolated CF positivity among hospitalized patients, predominantly rheumatology and systemic sclerosis patients, appears higher than rates previously reported in literature. We propose CF test recommendations should be included in investigation protocols for diseases where cryofibrinogenemia may occur.

Cryoglobulins, Cryofibrinogens, and Cold Agglutinins in Cold Urticaria: Literature Review, Retrospective Patient Analysis, and Observational Study in 49 Patients.

Introduction: Cryoproteins, such as cryoglobulins, cryofibrinogens and cold agglutinins, precipitate at low temperatures or agglutinate erythrocytes and dissolve again when warmed. Their pathogenetic and diagnostic importance in cold urticaria (ColdU) is unclear. In this study, we aimed to characterize the prevalence of cryoproteins in patients with ColdU. Methods: We conducted 3 analyses: i) a systematic review and meta-analysis of published data using an adapted version of the Joanna Briggs Institute's critical appraisal tool for case series, ii) a retrospective analysis of 293 ColdU patients treated at our Urticaria Center of Reference and Excellence (UCARE) from 2014 to 2019, and iii) a prospective observational study, from July 2019 to July 2020, with 49 ColdU patients as defined by the EAACI/GA2LEN/EDF/UNEV consensus recommendations. Results: Our systematic review identified 14 relevant studies with a total of 1151 ColdU patients. The meta-analyses showed that 3.0% (19/628), 1.1% (4/357) and 0.7% (2/283) of patients had elevated levels of cryoglobulins, cryofibrinogens and cold agglutinins, respectively. Our retrospective analyses showed that cryoproteins were assessed in 4.1% (12/293) of ColdU patients. None of 9 ColdU patients had cryoglobulins, and one of 5 had cold agglutinins. In our prospective study, none of our patients had detectable cryoglobulins (0/48) or cryofibrinogens (0/48), but 4.3% (2/46) of patients had cold agglutinins (without any known underlying autoimmune or hematological disorder). Conclusion: Our investigation suggests that only very few ColdU patients exhibit cryoproteins and that the pathogenesis of ColdU is driven by other mechanisms, which remain to be identified and characterized in detail.

High prevalence of cryofibrinogenemia in patients with chilblains during the COVID-19 outbreak.

BACKGROUND: Many cutaneous manifestations have been described in possible association with the COVID-19 pandemic, including acral lesions resembling chilblains. The underlying pathomechanisms of COVID-19 chilblains are not fully understood. The aim of this study was to describe the clinical, pathological, and laboratory findings of a series of patients who developed chilblains during the COVID-19 outbreak and to investigate the possible factors that could be involved in the pathogenesis of these lesions. METHODS: We conducted a prospective cohort study that included 54 patients who presented with chilblains during the highest peak in the incidence of COVID-19 in Cantabria (northern Spain). Skin biopsies were performed on 10 of these patients who presented with recent lesions. Laboratory investigations, including immunological analysis, serological studies, and the assessment of cryoproteins, were also performed. RESULTS: Most patients presented erythematous plaques located on the toes and/or purpuric macules located on the feet. Histopathological findings were compatible with those of idiopathic chilblains. Immunohistochemical evaluation showed C3d and C4d deposits in the vessel walls in seven cases. The autoimmunity panel was negative in most of our series. Cryoprotein testing showed positive cryofibrinogen in two-thirds (66.7%) of the patients assessed. On follow-up, most patients presented almost complete resolution, although six patients required prednisone and antiaggregant drug treatment. CONCLUSIONS: This study shows, for the first time to our knowledge, a high prevalence of cryofibrinogenemia in patients with chilblains during the COVID-19 pandemic. Cryofibrinogenemia could be implicated in the pathogenesis of chilblains related to COVID-19.

Characteristic electron-microscopic features of cryofibrinogen-associated glomerulonephritis: a case report.

BACKGROUND: Cryofibrinogenemia is a rare disorder that mainly affects the skin and occasionally the kidney. However, there are few published reports of cryofibrinogenemia-associated renal pathology. We therefore report a patient with cryofibrinogen-associated glomerulonephritis. Samples from this patient were examined by electron microscopy, laser microdissection, and liquid chromatography-tandem mass spectrometry (LC-MS/MS). CASE PRESENTATION: A 78-year-old Japanese man presented with declining renal function, proteinuria, and gross hematuria. Kidney biopsy showed a membranoproliferative pattern with crescent formation and dominant C3c deposition in which subendothelial deposits with uniquely organized electron-microscopic features were observed. Additional ultrastructural analysis of cryoprecipitates extracted from plasma revealed similar structures of the glomerular subendothelial deposits. LC-MS/MS identified an increase in fibrinogen α, ß, and γ chains, fibronectin, filamin-A, and C3. The glomerular lesions were diagnosed as cryofibrinogen-associated glomerulonephritis on the basis of these findings. CONCLUSIONS: Although there are few reports of cryofibrinogen-associated glomerulonephritis, we believe that accurate diagnosis can be achieved by performing LC-MS/MS and ultrastructural analysis.

Association between fibrinogen and fibrinogen γ' and atherosclerotic plaque morphology and composition in symptomatic carotid artery stenosis: Plaque-At-RISK study.

INTRODUCTION: Von Willebrand Factor (VWF), ADAMTS13, fibrinogen and fibrinogen γ' are associated with an increased risk of ischemic stroke. Carotid atherosclerosis is an important risk factor for ischemic stroke. Characteristics of the vulnerable plaque; intraplaque hemorrhage (IPH), plaque ulceration and lipid-rich necrotic core (LRNC) can be visualized with imaging techniques. Since atherosclerosis might attribute to the association between coagulation factors and ischemic stroke risk, the aim of this study is to investigate the association between coagulation factors and atherosclerotic plaque characteristics in more detail. MATERIALS AND METHODS: In 182 patients of the Plaque-At-RISK study (prospective multicenter cohort study) with a recent transient ischemic attack (TIA) or ischemic stroke and a symptomatic mild-to-moderate carotid artery stenosis, we measured VWF antigen (VWF:Ag), ADAMTS13 activity, fibrinogen (Clauss), and fibrinogen γ'. Presence of plaque ulceration, IPH volume and LRNC volume were determined by Multidetector-Row Computed Tomography (MDCTA, n = 160) and Magnetic Resonance Imaging (MRI, n = 172). Linear regression analysis was used to assess the association between imaging biomarkers and coagulation factors. RESULTS: VWF:Ag or ADAMTS13 levels were not significantly associated with plaque ulceration, IPH and LRNC. We found an inverse association between fibrinogen and fibrinogen γ' and IPH volume (B = -23.40 mm3/g/L, p = 0.01 and B = -161.73 mm3/g/L, p = 0.01) and between fibrinogen and fibrinogen γ' and LRNC volume (B = -38.89 mm3 g/L, p < 0.01 and B = -227.06 mm3 g/L, p = 0.01). Additional adjustments for C-reactive protein (CRP) did not change the results. CONCLUSIONS: Fibrinogen and fibrinogen γ' are inversely associated with IPH volume and LRNC volume, independent of inflammation. CLINICAL TRIAL REGISTRATION: clinicaltrials.govNCT01208025.

Paraneoplastic hematological, biochemical, and hemostatic abnormalities in female dogs with mammary neoplasms / Anormalidades hematológicas, bioquímicas e hemostáticas de origem paraneoplásica em fêmeas caninas com neoplasia mamária

Paraneoplastic laboratory abnormalities are identified in several types of cancers in dogs and cats. In veterinary medicine, particularly in mammary cancer, there are few studies that correlate abnormal laboratory findings with tumor type and staging. The aim of this study was to evaluate hematological, biochemical, and hemostatic abnormalities and correlate them with mammary tumor staging in female dogs with mammary cancer. Blood samples from 24 female dogs were evaluated, and the hematological, biochemical, and hemostatic parameters were correlated with tumor staging obtained by physical examination, imaging exams, and histopathological surgical biopsies. The groups were organized according to tumor staging: group 1 (stages I and II), group 2 (stage III), and group 3 (stages IV and V). Anemia, neutrophilic leukocytosis, monocytosis, eosinophilia, thrombocytosis, hypoalbuminemia, hypocalcemia, hypoglycemia, and low blood urea were observed. The variables MCHC, TPP, and RDW were correlated with tumor staging with no clinical relevance. Thrombin time and fibrinogen were significant between the groups in the coagulation test, being associated with tumor staging. The findings suggest influence of the proinflammatory cytokines released during tumor growth.(AU)

Alterações laboratoriais de origem paraneoplásica são identificadas em diversos tipos de câncer de cães e gatos. Na medicina veterinária, existem poucos estudos que correlacionam os achados laboratoriais anormais com o tipo e estadiamento tumorais, principalmente em cadelas com neoplasia mamária. O objetivo deste estudo foi avaliar as alterações hematológicas, bioquímicas e hemostáticas em cadelas com neoplasia mamária e relacioná-las com o estadiamento tumoral. Foram coletadas amostras de sangue de 24 fêmeas caninas, e os parâmetros hematológicos, bioquímicos e hemostáticos obtidos foram relacionados com o estadiamento tumoral, realizado através do exame físico, exames de imagem e avaliação histopatológica após remoção cirúrgica. Os grupos foram organizados de acordo com o estadiamento tumoral em: Grupo 1 (estádios I e II), grupo 2 (estádio III) e grupo 3 (estádios IV e V). Observou-se anemia, leucocitose neutrofílica, monocitose, eosinofilia, trombocitose, hipoalbuminemia, hipocalcemia, hipoglicemia e diminuição de ureia sanguínea. As variáveis CHCM, PPT e RDW foram relacionadas com o estadiamento tumoral, porém sem relevância clínica. Nos testes de coagulação, o TT e o fibrinogênio apresentaram diferença significativa entre os grupos, sendo associado com estadiamento tumoral. Os resultados sugerem influência das citocinas pró-inflamatórias liberadas durante o crescimento do tumor.(AU)

Cryofibrinogen-Associated Glomerulonephritis.

Cryofibrinogen is an under-recognized cryoprotein. Cryofibrinogen is a cryoprecipitate that develops following plasma refrigeration, but does not occur in cold serum. People with cryofibrinogenemia may be asymptomatic, but this cryoprotein can be associated with thromboembolic disease, particularly affecting the skin. Kidney manifestations are relatively uncommon, but are likely underestimated. We describe clinical features and kidney biopsy results in 2 patients with cryofibrinogen-related kidney disease. Both patients presented with proteinuria and hematuria. One had significant cutaneous ulcers and palpable purpura. Kidney biopsy in both cases showed membranoproliferative glomerulonephritis with no immunoglobulin deposition. Weak segmental capillary wall fibrinogen staining was noted in glomeruli. Immunofluorescence studies following pronase digestion failed to reveal masked immunoglobulin deposits. Ultrastructural studies were distinctive and characterized by organized deposits of large-bore with multilayered tubular structures and fine fibrillary structures in a matrix. To confirm the composition of deposits, we extracted the cryoprecipitate from plasma of a patient and performed ultrastructural studies, which showed identical ultrastructural characteristics to those seen on the kidney biopsy. We also performed proteomic analysis of the cryoprecipitate that confirmed the presence of fibrinogen. Subsequent laboratory evaluation was positive for cryofibrinogen in both patients on multiple occasions. Appropriate therapy was instituted in both patients, which included prednisone, immunosuppressive therapy, and avoidance of cold exposure. In summary, we present clinical, kidney biopsy, and laboratory findings and the treatment and follow-up of cryofibrinogen-associated glomerulonephritis. Awareness of this entity will result in accurate diagnoses, appropriate investigation, and treatment.

Lack of association of plasma gamma prime (γ') fibrinogen with incident cardiovascular disease.

INTRODUCTION: The association of gamma prime (γ') fibrinogen; a fibrinogen γ chain variant generated via alternative mRNA processing, with cardiovascular disease (CVD) remains equivocal. We prospectively examine the association of plasma γ' fibrinogen with the incidence of multiple cardiovascular disease (CVD) endpoints, independent of established CVD risk factors and total fibrinogen. MATERIALS AND METHODS: We measured plasma γ' fibrinogen on plasma samples collected in 1992-1993 from adults ≥65years (n=3219) enrolled in the Cardiovascular Health Study, who were followed through 2013 for incident CVD events. RESULTS AND CONCLUSIONS: In multivariable Cox models adjusted for traditional CVD risk factors and total fibrinogen, the hazard ratio per 1 standard deviation (10.7mg/dl) increment of γ' fibrinogen was 1.02 (95%CI: 0.95-1.10) for coronary heart disease; 0.88 (0.77-1.00) for ischemic stroke; 1.07 (0.87-1.32) for peripheral artery disease; 1.00 (0.92-1.08) for heart failure and 1.01 (0.92-1.10) for CVD mortality. Likewise, we failed to show a statistically significant association of γ'/total fibrinogen ratio with any CVD endpoint. These results suggest that among the elderly, γ' fibrinogen does not add much to CVD prediction beyond traditional risk factors and total fibrinogen level.

[Dysfibrinogenemia developed in a pregnant woman who has fibrinogen AαThr312Ala (ACT/GCT) polymorphism].

Blood coagulation factors play an essential role in pregnancy. We describe a 30-year-old pregnant woman whose course was complicated by dysfibrinogenemia with polymorphism of fibrinogen AαThr312Ala (rs6050) GG genotype. She was admitted to our hospital for genital bleeding and a huge subchorionic hematoma at 6 gestational weeks. Her first pregnancy and delivery had been uneventful, whereas her second and third pregnancies had resulted in spontaneous abortions with massive subchorionic hematomas. Her fibrinogen activity level was 125 mg/dl and this was lower than her fibrinogen antigen level. We administered tranexamic acid early in the pregnancy, and the subchorionic hematoma diminished in size in accordance with the increase of her fibrinogen level. At 16 gestational weeks, her D-dimer levels were elevated, and heparin treatment was initiated as an alternative. A male infant was delivered at 36 gestational weeks. Intrapartum hemorrhage was 600 g. Patients with coagulation abnormalities are often asymptomatic in the absence of pregnancy. However, when they become pregnant, the spontaneous abortion rate is high. Careful observation and effective management of coagulation abnormalities are essential for such patients to carry their pregnancies to term.

Prospective study of γ' fibrinogen and incident venous thromboembolism: The Longitudinal Investigation of Thromboembolism Etiology (LITE).

INTRODUCTION: Epidemiological studies generally have not found plasma total fibrinogen to be a risk factor for venous thromboembolism (VTE), but several have reported associations between variants in the fibrinogen gamma gene (FGG) and VTE. A case-control study in whites suggested plasma γ' fibrinogen concentration may be associated inversely with VTE, but this was not replicated in African Americans. OBJECTIVE: To examine the prospective association between γ' fibrinogen concentrations and occurrence of VTE. METHODS: We used the Longitudinal Investigation of Thromboembolism Etiology (LITE), involving two pooled population-based cohorts in the United States including 16,234 participants. The cohorts comprised white and African American men and women, aged 50years and older at study onset in the early 1990s. We identified VTEs during follow-up and documented they met standardized diagnostic criteria. RESULTS: During two decades of follow-up, neither γ' fibrinogen nor total fibrinogen nor their ratio was associated with VTE overall (n=521 VTEs), in subgroups defined by race, or in other subgroups. In both race groups, the minor allele of FGG rs2066865 was associated with lower γ' fibrinogen concentrations, but this allele was not associated with VTE. CONCLUSIONS: A lower plasma concentration of γ' fibrinogen in healthy adults does not appear to increase VTE risk.

Association of Plasma γ' Fibrinogen With Incident Cardiovascular Disease: The Atherosclerosis Risk in Communities (ARIC) Study.

OBJECTIVES: To prospectively examine the association of plasma γ' fibrinogen with the incidence of multiple cardiovascular disease (CVD) end points, independent of established CVD risk factors, total fibrinogen, and other inflammatory markers. APPROACH AND RESULTS: The Atherosclerosis Risk in Communities (ARIC) study measured γ' fibrinogen by enzyme-linked immunosorbent assay in stored plasma samples from 1993 to 1995 and related levels in 10 601 adults to incident CVD end points (coronary heart disease [n=1603], ischemic stroke [n=548], peripheral artery disease [n=599], heart failure [n=1411], and CVD mortality [n=705]) through 2012 (median follow-up, 18 years). In Cox models accounting for established CVD risk factors and total fibrinogen levels, γ' fibrinogen was associated positively with peripheral artery disease (hazard ratio [HR] per 1-SD [8.80 mg/dL] increment, 1.14 [1.04-1.24]), heart failure (HR, 1.06 [1.01-1.13]), and CVD deaths (HR, 1.12 [1.04-1.21]) but not with incident coronary heart disease (HR, 1.01 [0.96-1.07]) or ischemic stroke (HR, 0.98 [0.89-1.07]). Additional adjustment for C-reactive protein, however, eliminated the associations with peripheral artery disease and heart failure. CONCLUSIONS: These findings do not lend support to the hypothesis that γ' fibrinogen influences CVD events through its prothrombotic properties. Rather, γ' fibrinogen concentrations seem to reflect general inflammation that accompanies and may contribute to atherosclerotic CVD, instead of γ' fibrinogen being a causal risk factor.

CVD risk factors are related to plasma fibrin clot properties independent of total and or γ' fibrinogen concentration.

INTRODUCTION: Cardiovascular disease (CVD) risk factors are associated with total fibrinogen concentration and/or altered clot structure. It is however, unclear whether such associations with clot structure are ascribed to fibrinogen concentration or other independent mechanisms. We aimed to determine whether CVD risk factors associated with increased total and/or γ' fibrinogen concentration, were also associated with altered fibrin clot properties and secondly whether such associations were due to the fibrinogen concentration or through independent associations. MATERIALS AND METHODS: In a plasma setting CVD risk factors (including total and γ' fibrinogen concentration) were cross-sectionally analysed in 2010 apparently healthy black South African participants. Kinetics of clot formation (lag time, slope and maximum absorbance) as well as clot lysis times were calculated from turbidity curves. RESULTS: Of the measured CVD risk factors age, metabolic syndrome, C-reactive protein (CRP), high density lipoprotein (HDL)-cholesterol and homocysteine were significantly associated with altered fibrin clot properties after adjustment for total and or γ' fibrinogen concentration. Aging was associated with thicker fibres (p=0.004) while both metabolic syndrome and low HDL-cholesterol levels were associated with lower rates of lateral aggregation (slope), (p=0.0004 and p=0.0009), and the formation of thinner fibres (p=0.007 and p=0.0004). Elevated CRP was associated with increased rates of lateral aggregation (p=0.002) and consequently thicker fibres (p<0.0001). Hyperhomocysteinemia was associated with increased rates of lateral aggregation (p=0.0007) without affecting fibre thickness. CONCLUSION: Final clot structure may contribute to increased CVD risk in vivo through associations with other CVD risk factors independent from total or γ' fibrinogen concentration.

Cryofibrinogen levels are increased in non-traumatic osteonecrosis: a new pathogenic clue to osteonecrosis?

OBJECTIVE: To determine whether levels of cryofibrinogen are increased in non-traumatic osteonecrosis (ON) and could correlate with disease staging. METHODS: We prospectively analysed cryofibrinogen levels by immunofixation electrophoresis in 50 patients with non-traumatic ON, 50 healthy volunteers and 8 patients with traumatic ON. Staging of disease involving the femoral heads and the size of necrotic lesions were assessed by the Association Research Circulation Osseous (ARCO) classification system. RESULTS: Mean cryofibrinogen levels in patients with non-traumatic ON were significantly increased relative to healthy controls and to patients with traumatic ON (222.1 ± 20.6, 59.9 ± 5.6 and 52.3 ± 14.9 mg/dl, respectively, P < 0.001). In the non-traumatic ON group, mean cryofibrinogen levels were significantly increased in patients with multifocal ON compared with patients with mono/bifocal ON (276.5 ± 56.5 and 149.3 ± 15.4 mg/dl, respectively, P = 0.03). There were no significant differences in cryofibrinogen levels observed with respect to the size of the necrotic lesions involving the femoral heads. Moreover, cryofibrinogen levels in patients with ON of the femoral heads classified according to the stage of disease were not significantly different between patients with stage 1/2 and patients with stage 3 ON (179.2 ± 31.3 vs 204.1 ± 29.0 mg/dl, respectively; P = 0.813). CONCLUSION: Cryofibrinogen levels are increased in non-traumatic ON and, more importantly, in multifocal ON. The fact that cryofibrinogen levels are not correlated with the size of lesions and the stage of disease could imply systemic rather than local involvement characterizing the pathogenesis of ON.

Glycaemic indices and non-traditional biochemical cardiovascular disease markers in a diabetic population in Nigeria.

OBJECTIVE: To determine the frequency of hyperfibrinogenaemia, elevated C-reactive protein, hyperuricaemia and elevated lipoprotein A in a clinic population of patients with type 2 Diabetes mellitus (DM) compared with healthy controls; and determine the interrelationship between fasting plasma glucose levels and indices of long-term glycaemic control (fructosamine and glycosylated haemoglobin) in DM. STUDY DESIGN: Cross-sectional, analytical study. PLACE AND DURATION OF STUDY: The study was conducted at the Lagos State University Teaching Hospital, Ikeja, from April to June 2009. METHODOLOGY: A total of 200 patients with type 2 DM and 100 age and gender matched healthy controls were recruited for the study. Glycaemic control was assessed using fasting blood glucose, fructosamine and glycosylated haemoglobin levels. The non-traditional risk factors studied included C-reactive protein (CRP), Lipoprotein a (Lpa), serum uric acid (SUA), microalbuminuria and fibrinogen. Mann-whitney, chi-square and Pearson's correlation tests were used for analysis as applicable. RESULTS: Hyperfibrinoginaemia, elevated CRP, LPa, microalbuminuria and hyperuricaemia were present in 3.5%, 65%, 12%, 6% and 57% respectively in type 2 DM. The mean levels of these CV risk factors were significantly higher in subjects with type 2 DM than that of the control subject. There was a positive and significant correlation between HbA1c and FBS (r=0.46, p=0.0001) and HbA1c and fructosamine (r=0.49, p=0.0001). All studied CVS risk factors were related to indices of glycaemic control which were found to be interrelated. Fasting blood glucose significantly correlated with both HbA1c and fructosamine but HbA1c showed better correlation to FPG than fructosamine (r=0.51 vs. 0.32). CONCLUSION: Glycosylated haemoglobin and fasting plasma glucose but not fructosamine are significantly associated with microalbuminuria, fibrinogen SUA and CRP in type 2 DM. HbA1c was found to be better than fructosamine in monitoring overall long-term glycaemic control.

Assessment of genetic determinants of the association of γ' fibrinogen in relation to cardiovascular disease.

OBJECTIVE: γ' fibrinogen is a newly emerging biomarker that is associated with cardiovascular disease (CVD). However, the genetic determinants of γ' fibrinogen levels are unknown. We therefore conducted a genome-wide association study on 3042 participants from the Framingham Heart Study Offspring Cohort. METHODS AND RESULTS: A genome-wide association study with 2.5 million single-nucleotide polymorphisms (SNPs) was carried out for γ' fibrinogen levels from the cycle 7 examination. Fifty-four SNPs in or near the fibrinogen gene locus demonstrated genome-wide significance (P<5.0×10(-8)) for association with γ' fibrinogen levels. The top-signal SNP was rs7681423 (P=9.97×10(-110)) in the fibrinogen gene locus near FGG, which encodes the γ chain. Conditional on the top SNP, the only other SNP that remained genome-wide significant was rs1049636. Associations between SNPs, γ' fibrinogen levels, and prevalent CVD events were examined using multiple logistic regression. γ' fibrinogen levels were associated with prevalent CVD (P=0.02), although the top 2 SNPs associated with γ' fibrinogen levels were not associated with CVD. These findings contrast those for total fibrinogen levels, which are associated with different genetic loci, particularly FGB, which encodes the Bß chain. CONCLUSIONS: γ' fibrinogen is associated with prevalent CVD and with SNPs exclusively in and near the fibrinogen gene locus.

γ'/total fibrinogen ratio is associated with short-term outcome in ischaemic stroke.

Fibrinogen γ' (γ') is a natural isoform of fibrinogen, and alters the rate of formation and the properties of clots. It could therefore affect outcome after ischaemic stroke. The prognostic significance of γ' fibrinogen levels is, however, still unclear. It was the objective of this study to assess levels of γ' in ischaemic stroke, and its association with short-term outcome. We included 200 ischaemic stroke patients and 156 control persons. Total fibrinogen and γ' levels were measured; outcome at discharge was assessed by means of the modified Rankin Scale score (defined as unfavourable when >2). We compared levels between patients and controls using multiple linear regression analysis, and logistic regression analysis was used to assess the relationship between levels and outcome. All analyses were adjusted for age and sex. Mean γ' levels were significantly higher in patients with ischaemic stroke than in controls (0.37 vs. 0.32 g/l, p<0.001), and patients also had a higher γ'/total fibrinogen ratio (0.102 vs. 0.096, p=0.19). The γ'/total fibrinogen ratio is associated with unfavourable outcome in patients with ischaemic stroke (odds ratio per unit increase of γ'/total fibrinogen ratio 1.27, 95% confidence interval 1.09-1.47). Our study shows that patients with ischaemic stroke have increased levels of fibrinogen γ' and suggests a trend towards an increased γ'/total fibrinogen ratio in ischaemic stroke. Increased fibrinogen γ' relative to total fibrinogen levels are associated with unfavourable outcome in the early phase after stroke.

[Automated hematology analysers and spurious counts. Part 1. Platelets]. / Anomalies et erreurs de détermination de l'hémogramme avec les automates d'hématologie cellulaire. Partie 1. Les plaquettes sanguines.

Hematology analysers provide now quick, accurate, and reproducible cell blood counts. However, depending on detection methods, spurious counts may occur. If undetected, such spurious counts may lead to inappropriate medical care and to unneeded explorations. Focusing first on platelet counts, situations leading to spurious decrease include several preanalytical considerations, the major one corresponding to EDTA-induced platelet aggregation and to platelet satellitism around polymorphs. In other instances, related to the presence of small particles mimicking platelets, including fragmented red blood cells, lipids, cryoglobulins, fibrin strands, or cytoplasmic fragments of leukocytes, spurious elevation of platelet count may occur. According to the analyser and to the methods used for the determination of the cell blood count, flags or messages related to these spurious changes differ. For each spurious change, the authors describe the mechanism leading to the anomaly, the way the analysers generate flags, and what should be done to provide accurate results.