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The AMME syndrome defined as the combination of Alport syndrome, intellectual disability, midface hypoplasia, and elliptocytosis (AMME) is known to be a contiguous gene syndrome associated with microdeletions in the region Xq22.3q23. Recently, using exome sequencing, missense pathogenic variants in AMMECR1 have been associated with intellectual disability, midface hypoplasia, and elliptocytosis. In these cases, AMMECR1 gene appears to be responsible for most of the clinical features of the AMME syndrome except for Alport syndrome. In this article, we present two unrelated male patients with short stature, mild intellectual disability or neurodevelopmental delay, sensorineural hearing loss, and elliptocytosis harboring small microdeletions identified by array-CGH involving TMEM164 and AMMECR1 genes and SNORD96B small nucleolar RNA for one patient, inherited from their mothers. These original cases further confirm that most specific AMME features are ascribed to AMMECR1 haploinsufficiency. These cases reporting the smallest microdeletions encompassing AMMECR1 gene provide new evidence for involvement of AMMECR1 in the AMME phenotype and permit to discuss a phenotype related to AMMECR1 haploinsufficiency: developmental delay/intellectual deficiency, midface hypoplasia, midline defect, deafness, and short stature.

International audience; Objectives: To evaluate the applicability and compliance with guidelines for early initiation of long-term prophylaxis in infants with severe hemophilia A and to identify factors associated with guideline compliance.Study design: This real-world, prospective, multicenter, population-based FranceCoag study included almost all French boys with severe hemophilia A, born between 2000 and 2009 (ie, after guideline implementation).Results: We included 333 boys in the study cohort. The cumulative incidence of long-term prophylaxis use was 61.2% at 3 years of age vs 9.5% in a historical cohort of 39 boys born in 1996 (ie, before guideline implementation). The guidelines were not applicable in 23.1% of patients due to an early intracranial bleeding or inhibitor development. Long-term prophylaxis was delayed in 10.8% of patients. In the multivariate analysis, 2 variables were significantly associated with "timely long-term prophylaxis" as compared with "delayed long-term prophylaxis": hemophilia treating center location in the southern regions of France (OR 23.6, 95% CI 1.9-286.7, P = .013 vs Paris area) and older age at long-term prophylaxis indication (OR 7.2 for each additional year, 95% CI 1.2-43.2, P = .031). Long-term prophylaxis anticipation was observed in 39.0% of patients. Earlier birth year (OR 0.5, 95% CI 0.3-0.8, P = .010 for birth years 2005-2009 vs 2000-2004) and age at first factor replacement (OR 1.9 for each additional year, 95% CI 1.2-3.0, P = .005) were significantly associated with "long-term prophylaxis guideline compliance" vs "long-term prophylaxis anticipation."Conclusions: This study suggests that long-term prophylaxis guidelines are associated with increased long-term prophylaxis use. However, early initiation of long-term prophylaxis remains a challenge.

International audience; We describe the clinical, hematologic and genetic characteristics of a retrospective series of 126 subjects from 64 families with hereditary xerocytosis. Twelve patients from six families carried a KCNN4 mutation, five had the recurrent p.Arg352His mutation and one had a new deletion at the exon 7-intron 7 junction. Forty-nine families carried a PIEZO1 mutation, which was a known recurrent mutation in only one-third of the cases and private sequence variation in others; 12 new probably pathogenic missense mutations were identified. The two dominant features leading to diagnosis were hemolysis that persisted after splenectomy and hyperferritinemia, with an inconstant correlation with liver iron content assessed by magnetic resonance imaging. PIEZO1-hereditary xerocytosis was characterized by compensated hemolysis in most cases, perinatal edema of heterogeneous severity in more than 20% of families and a major risk of post-splenectomy thrombotic events, including a high frequency of portal thrombosis. In KCNN4-related disease, the main symptoms were more severe anemia, hemolysis and iron overload, with no clear sign of red cell dehydration; therefore, this disorder would be better described as a ‘Gardos channelopathy’. These data on the largest series to date indicate that PIEZO1-hereditary xerocytosis and Gardos channelopathy are not the same disease although they share hemolysis, a high rate of iron overload and inefficient splenectomy. They demonstrate the high variability in clinical expression as well as genetic bases of PIEZO1-hereditary xerocytosis. These results will help to improve the diagnosis of hereditary xerocytosis and to provide recommendations on the clinical management in terms of splenectomy, iron overload and pregnancy follow-up.

We report two new point mutations causing alpha-thalassemia (alpha-thal) that could not be characterized by conventional biochemical studies. The first mutation is a single base substitution at codon 123 of the alpha1-globin gene [alpha123(H6)Ala--Pro, GCCCCC (alpha1)] and leads to the substitution of a proline residue in the H helix. The resulting unstable hemoglobin (Hb) variant has been named Hb Voreppe. The second is a frameshift of the alpha2 gene due to a deletion (-C), either of the third base of codon 112 or of the first base of codon 113, that causes a premature stop codon at position 132.

Two new fetal hemoglobin (Hb F) variants affecting the Gγ chain are reported: Hb F-Saint-Etienne [Gγ79(EF3)Asp→His] and Hb F-Lyon [Gγ97(FG4)His→Arg]. These new Hb variants were found during a neonatal screening for hemoglobinopathies but characterized a few months later by our reference laboratory. The corresponding mutations are located on the external part of the Hb molecule and seem to be clinically silent.

We report a new mutation on the α2-globin gene causing α(+)-thalassemia (α(+)-thal) with a deletion of a single nucleotide (T) at amino acid residue 43 [HBA2:c.130delT or HBA2:c.131delT]. This frameshift deletion gives rise to a premature termination codon at codon 47.

Renal interstitial expansion is now considered a useful marker of progression of several nephropathies. This study describes a multicenter, prospective, double-blind, pla- cebo-controlled, randomized trial of the effects of Perindopril (4 mg/d) on kidney structure and function over 2 yr in 26 type 2 diabetic patients with proteinuria ranging from 70 to 4210 mg/d and relatively preserved GFR (creatinine clearance .60 ml/min). All patients underwent baseline renal biopsy, but four (15%) were not randomized because of the presence of non- diabetic nephropathy. The remaining 22 were randomized (11 to Perindopril (PE), 11 to placebo (PO)), and 19 (9 PE, 10 PO) underwent follow-up biopsy at 2 yr. BP was controlled equally in both groups throughout. Proteinuria increased in PO patients (11562 mg/d) but declined in PE patients (2156 mg/d) (P , 0.05). Morphometric analysis was performed by light micros- copy using a Biocom computer. Over the 2 yr, mean cortical interstitial fractional volume identical at baseline increased significantly in PO patients (31.7 6 5.3 versus 40.2 6 11.1%; P 5 0.001) but was unchanged in PE patients (33.8 6 4.9 versus 34.7 6 6.6%; P 5 0.50). It is concluded that: (1) nondiabetic nephropathy is present in approximately 15% of albuminuric type 2 diabetic patients; and (2) Perindopril pre- vents interstitial expansion in hypertensive patients with biopsy-proven diabetic glomerulopathy. These results support a role of angiotensin II in the progression of interstitial changes in type 2 diabetic patients with nephropathy.

Resume Les D-dimeres plasmatiques, produits de degradation de la fibrine stabilisee, representent une aide diagnostique pour l'exclusion de l'embolie pulmonaire (EP) et de la thrombose veineuse profonde (TVP), evaluee chez les patients ambulatoires. Nous avons voulu determiner quelle etait la place du dosage des D-dimeres en milieu hospitalier pour l'ensemble des patients cliniquement suspects de thrombose veineuse profonde et/ou d'embolie pulmonaire. Nous rapportons les resultats d'une etude retrospective cas-temoins concernant 300 patients hospitalises, non selectionnes avant leur inclusion, ou le dosage des D-dimeres a ete effectue par Elisa. Les vrais negatifs s'elevent a 45 % chez les patients des urgences, ce qui confirme les resultats publies pour les patients ambulatoires, pour lesquels l'utilite des D-dimeres a ete demontree. Chez les malades hospitalises, nous demontrons l'utilite des D-dimeres pour les patients qui repondent aux trois criteres suivants: âge

Matrix metalloproteinases (MMPs) are involved in the regulation of extracellular matrix turnover and tissue remodeling, through which they can influence the infiltration of a graft by immune-competent cells. Little is known about their role in islet allograft rejection. Therefore we investigated the expression of several MMPs and of two of their tissue inhibitors (TIMPs) in rat pancreatic islets. MMP and TIMP expression in isolated rat pancreatic islets was assessed by reverse transcriptase-polymerase chain reaction (RT-PCR) from total RNA. Several MMPs of different substrate specificities were found to be expressed in rat pancreatic islets, either shortly after islet isolation and in all conditions tested (MMP-9, TIMP-1) or after a lag time (MMP-2, MMP-3, MMP-14, TIMP-2). Fetal calf serum induced MMP-7 expression. The inflammatory cytokine interleukin-1 beta (IL-1 beta) did not induce MMP or TIMP expression. We showed that rat pancreatic islets are well equipped with MMPs and TIMPs, but the functional meaning of this expression remains to be elucidated. On the basis of the known effects on tissue remodeling and cytokine processing, we anticipate that they can influence islet engraftment and viability and participate to islet graft rejection.

Matrix metalloproteinases (MMPs) are involved in the remodeling of connective tissue as well as in disease states associated with acute and chronic inflammation or tumoral metastatic processes. Despite detailed and extensive studies of the mechanisms of lymphocyte extravasation, remarkably little is known about the expression and regulation of metalloproteinases involved in the migratory process. By using zymography and reverse transcription-polymerase chain reaction experiments, we have demonstrated that Epstein-Barr virus-immortalized B lymphocytes are able to secrete a 92-kDa metalloproteinase with gelatinolytic activity which has been purified and identified as being MMP-9. Moreover, the tissue inhibitor of metalloproteinase was shown to be constitutively expressed by the B cells. The expression of 92-kDa gelatinase is mediated by cytokines, growth factors, lipopolysaccharide, concanavalin A, and the tumor promotor phorbol 12-myristate 13-acetate. Time dependence activity increased rapidly up to 24 h of incubation with lipopolysaccharide or concanavalin A stimulation while it requires a delay and more time to have an optimum effect when cytokines were the stimulating agents; transforming growth factor-β abolished 92-kDa gelatinase production. Both staurosporine and wortmannin are inductive stimuli, and the level of MMP-9 secreted into the media is greater than that observed with other agents except concanavalin A. Elicitation of the chemotactic migration of B cells through a model basement membrane by lipopolysaccharide was shown to be correlated with gelatinase expression and inhibited by 7 mm captopril. Our study indicates that Epstein-Barr virus-B lymphocytes express 92-kDa gelatinase, the production of which can be modified by a variety of physiological and pharmacological signals which have been shown to differ according to the cell type.

Gelatinolytic enzymes, which degrade type IV basement membrane collagen, have been shown to be expressed by corneal cells, either constitutively (gelatinase A or MMP-2) or after induction (gelatinase B or MMP-9). Our aim was to determine whether an enhanced MMP-9 and eventually MMP-2 concentration in tears could be evidenced in the case of corneal-graft failure.The amount of MMP-2 and MMP-9 gelatinolytic enzymes was measured by quantitative zymography in tears of twenty-one controls (84 samplings) and in tears of twenty-three corneal-grafted patients in a one-year post-graft follow-up study.The mean MMP-2 values in controls were of 8.4 (+/-7.3) pg/10 micrograms protein and the mean MMP-9 values in controls were of 73 (+/-76) pg/10 micrograms protein. No active gelatinase form was detected in any of controls, but in all cases of corneal graft failure, the active forms of both enzymes were present, and enzyme concentrations were higher than control values. All patients had significantly higher MMP-9 values than controls at each sampling time (p0.0001). The "corneal-graft failure" patient group had statistically significant higher MMP-9 concentrations in tears than the "successful-graft" patient group at one month (p = 0.0312), four months (p = 0.0158) and one year (p0.01) after the graft. The presence of active MMP-9 was highly significant of graft failure four months and one year after the graft (p0.0001). In contrast, MMP-2 increase was delayed, with significantly higher MMP-2 values than controls in all patients at four months (p = 0.0231) and one year (p = 0.0001) after the graft, but MMP-2 values could not discriminate between patient groups.In our study, all cases of graft failure showed abnormally high levels of the active forms of metalloproteinase enzymes, and these values far exceeded the maximum control concentration. MMP-9 measurements in tears made between one and four months after corneal transplantation, and while local corticotherapy is steadily established, should help in predicting corneal graft rejection.

In response to bacterial endotoxin (lipopolysaccharide, LPS) monocytes synthesize and express on their surface tissue factor (TF) which triggers the blood coagulation cascade. Since LPS stimulates active oxygen species production by these cells, we investigated the roles of superoxide anion and nitric oxide in the induction of TF in human blood monocytes. Scavengers of reactive oxygen intermediates such as N-acetyl cys-teine or pyrrolidine dithiocarbamate were able to block TF induction. In addition, inhibition of NADPH oxidase and/or NO synthase which are major sources of active oxygen species in phagocytes also blocked TF induction. The restoration of TF expression, in monocytes treated with inhibitors of reactive oxygen production, by NN’-dimethyl-γγ‘-dipyridylium dichloride and/or sodium nitrosylpentacyanoferrate (III), which generate respectively O-2 and NO, suggests that these two radicals participate in the induction of TF at the surface of blood monocytes stimulated by LPS.

Transmigrating neutrophils secrete a 92 kDa gelatinase (MMP-9) in order to degrade type IV endothelial basement membrane collagen. A model system for neutrophil adhesion combining a short pre-adhesion time (30 min) in plastic or endothelium-coated wells, medium removal and addition of soluble stimuli (fMLP, TNF alpha), enabled us to induce the release of a basal level of gelatinase activity (12% total cell content) from tertiary granules, while the release of vitamin B12 binding protein from specific granules was limited to 4% total cell content. Neutrophil gelatinase activity in unfractionated supernatants from endothelium-coated wells was significantly reduced (P0.01) compared to levels obtained on plastic supports, even after TNF alpha treatment or when cell populations were physically separated by trans-well inserts. In contrast, gelatin zymograms of supernatants from plastic and endothelium-coated wells remained similar. These findings suggest that MMP-9 is equally secreted but differentially inhibited by the tissue inhibitor of metalloproteinase-1 originating from the neutrophils. MMP-9 RT-PCR from neutrophils, assessed after up to one hour adhesion on plastic, yielded a single 270 bp fragment which was almost undetectable in the endothelial RT-PCR counterpart, whereas the TIMP-1 PCR product was apparent in both cell types. Furthermore, neutrophil adhesion on endothelial cells and TNF alpha activation for one hour induced the disappearance of MMP-9 cDNA without changes in TIMP-1 and beta-actin PCR products. These results suggest the existence of a dual down-regulation during neutrophil-endothelial interaction, both at the level of secreted MMP-9 activity and of MMP-9 gene transcription.

We report, in a constitutionally heterozygous carrier of the sickle-cell trait, an abnormally low HbS level (12%) caused by a somatic deletion of the HBB gene (βS allele) that occurred presumably in an early precursor of the hematopoietic lineage.

Mild or moderate hyperhomocysteinemia as a risk factor for venous thrombosis is still a matter of debate. The strength of this study is to bring a body of elements to evaluate whether hyperhomocysteinemia should be used as a biomarker for venous thromboembolism (VTE). These elements consist of a biological evaluation of several hematological risk factors, and an original control group made of patients with a negative Doppler ultrasonography. A total of 151 cases and 155 controls were included. Total plasma homocysteine level, MTHFR C677T polymorphism, inherited abnormalities of the natural anticoagulant system as well as plasma folate and cobalamin levels were determined. A total of 41 (27.2 %) of cases and only 9 (5.8%) of controls had at least one of the coagulation defects studied. No significant difference was observed for total homocysteine levels between the 2 groups: median (interquartile range) = 8.3 (7.2-10.8) μmol/L for cases and 8.4 (7-10.9) μmol/L for controls. We found significantly more plasma folates and/or cobalamin deficiencies in controls (18.3%) than in cases (8.6%). After adjustment for several variables significantly related to risk factors of VTE, hyperhomocysteinemia (>" xbd="2200" xhg="2176" ybd="1302" yhg="1257"/>13.2 μmol/L) was not found statistically associated with VTE: odds ratio 1.36 (95% confidence interval, 0.52-3.54). The prevalence of the homozygous 677TT polymorphism in the MTHFR gene was not increased in cases compared with controls. Mild or moderate hyperhomocysteinemia does not seem to be a strong determinant in VTE not only when the control group does not exclusively include healthy persons but also in investigated disease-free (thromboembolic disease) controls.

Two new fetal hemoglobin (Hb F) variants affecting the (G)gamma chain are reported: Hb F-Saint-Etienne [G gamma 79(EF3)Asp--His] and Hb F-Lyon [G gamma 97(FG4)His--Arg]. These new Hb variants were found during a neonatal screening for hemoglobinopathies but characterized a few months later by our reference laboratory. The corresponding mutations are located on the external part of the Hb molecule and seem to be clinically silent.

Cardiovascular disease (CVD) remains the major cause of death in patients with end-stage renal disease (ESRD). Traditional risk factors do not explain the high prevalence of CVD in this population, and other non-traditional cardiovascular (CV) risk markers have now been described. Therefore, the potential relationship between CVD and phenotypic and genotypic risk markers was investigated prospectively in incident dialysis patients cohort. The 279 patients (244 on hemodialysis, 35 on peritoneal dialysis) within the Diamant Alpin Dialysis Cohort Study were investigated. Phenotypic and genotypic parameters were determined at dialysis initiation, patients monitored over a 2-year period, and CV events (morbidity and mortality) recorded. Globally, 82 CV events occurred and 26 patients (9.3%) died from CVD, whereas 28 (10%) died from non-CV causes. Previous CV events were strongly predictive of CV events occurrence, whatever patients had had one (hazard ratio (HR) 2, 95% confidence intervals (CI) 1.1-3.5) or more (HR 3.9, 95% CI 2.1-7.1) CV accidents before starting dialysis. Both lipoprotein(a) (HR 1.67, 95% CI 1-2.5) and total plasma homocysteine at cutoff 30 micromol/l (HR 1.7, 95% CI 1.1-2.8) were independent predictors of CV events outcome. In the subgroup of patients with homocysteine < 30 micromol/l, methylenetetrahydrofolate reductase (MTHFR) TT was the sole biological parameter predictive of CV event outcome (HR 2.5, 95% CI 1.1-10, P = 0.03). ESRD patients who enter chronic dialysis with a previous CV event, high total homocysteinemia levels, or MTHFR 677TT genotype must be considered at high risk of incident CV events.

International audience; We performed a prospective study to assess whether positive quantitative D-dimer (DD) levels could be integrated for a selected population in a defined strategy to accurately diagnose pulmonary embolism (PE). For this purpose, 1528 in- or outpatients with clinically suspected PE were investigated according to our prescription rules. Clinical probability was defined as low, intermediate or high. Patients in whom DD levels were measured met criteria defined by our previously described decision-making algorithm: in- and outpatients, < 80 years, without surgery in the previous 30 days or active cancer. Nine hundred and twenty-three patients (60.4%) had quantitative DD measurement using automated latex DD assay (STA-Liatest D-Di). According to our decision-making algorithm, DD measurement was applied to 70.5% of out-, and 55.7% of inpatients, and PE diagnosis was ruled out in 49.5% of the 923 patients. This allowed us to confirm prospectively that our specific rules greatly improve the DD testing efficiency. PE was diagnosed in 115 (12.5%) patients. For a 0.5 mg L(-1) cut-off, the test sensitivity was 97.4%, but its specificity was only 56.7%. However, PE prevalence increased gradually with DD levels. The true observed PE prevalence, according to the quantitative assessment of DD levels, differed from that predicted with pretest clinical probability only. Moreover, in this well-defined patient group, a quantitative DD level > 2 mg L(-1) was predictive of PE occurrence independently of the clinical score (odds ratio 6.9, 95% confidence interval 3.7, 12.8). As part of a defined strategy, knowledge of positive DD quantitative value, together with the clinical probability score, improves the PE predictive model. A clinical validation of these results in a follow-up study would now be necessary before considering the implementation of this strategy into clinical practice.

The diagnosis of polycythemia vera (PV) is based on clinical and biological criteria defined by either the Polycythemia Vera Study Group (PVSG) or the World Health Organization (WHO). Both the PVSG and WHO PV criteria have proved helpful and are extensively used, yet diagnostic strategies and scheduling of biological investigations vary. We assessed the value of measuring serum erythropoietin (Epo) as a first intention diagnostic test in patients with absolute erythrocytosis (AE).Serum and bone marrow (BM) samples of 241 patients with a suspicion of erythrocytosis were collected in 8 hospital centers. One hundred and ninety had an absolute erythrocytosis (116 had PV, 66 had secondary erythrocytosis and 4 had idiopathic erythrocytosis). Serum Epo was assayed (ELISA) in 186. Statistical analysis (ROC curves) was used to define serum Epo thresholds that were specific for PV and secondary erythrocytosis and to analyze the diagnostic value of a low or high serum Epo level.A large majority of PV patients (87% or 101/116) had a serum Epo level below the normal range in healthy patients (3.3 IU/L), giving this value a specificity of 97% with a 97.8% positive predictive value for the diagnosis of PV. Statistical analysis (ROC curves) defined two thresholds allowing a specific and direct diagnosis of 65.6% (65/99) of untreated PV (Epo1.4 IU/L) and 19.7% (13/66) of those with secondary erythrocytosis (Epo13.7 IU/L).Based on these data, we propose that measurement of serum Epo level, a simple, reliable and inexpensive test, should be considered as a first intention diagnostic test for patients with absolute erythrocytosis.

Clinical and therapeutic characteristics of chronic dialysis patients vary widely at national and/or regional levels. Their increased cardiovascular (CV) mortality is not explained by traditional cardiovascular disease (CVD) risk factors only. Therefore, this study aimed to investigate and compare the characteristics of patients starting dialysis in a homogeneous Alpin region and possibly to identify new biological parameters (phenotypes or genotypes), which eould be responsible for the increased CVD seen in end-stage renal disease (ESRD) patients.A cohort of 279 non-selected consecutive patients entering a dialysis program was prospectively investigated in eight centers of three adjacent regions in France, Italy and Switzerland. In addition to the usual demographic, clinical and biological data, we analyzed at study entry the blood levels of homocysteine, lipoprotein(a) (Lp(a)) and antioxidized low density lipoprotein (LDL) antibodies, vitamin B12 status, Lp(a) and haptoglobin phenotypes, methylenetetrahydrofolate reductase (MTHFR), angiotensin-converting enzyme (ACE), allele epsilon E4 of apolipoprotein (ApoE4) and plasminogen activator inhibitor-1 (PAI-1) genetic polymorphism.At entry, 90.3% of patients were hypertensive, 30% had type 2 diabetes mellitus and 17.6% were current smokers; 42% of patients had already experienced at least one CV event: peripheral artery disease (26% of the cohort), coronary artery disease (22%) or ischemic cerebro-vascular disease (16%). Forty-two patients had hador =2 CV events or documented atherosclerotic localizations. Anemia was not optimally treated: mean hemoglobin (Hb) was at 97.7 g/L and, while overall 62% of patients received erythropoietin (EPO) prior to dialysis, large national differences were observed. Compared to the reference population, ESRD patients exhibited increased homocysteinemia, Lp(a) levels and ApoE4 allele prevalence. Conversely, the distribution of Lp(a) phenotype, MTHFR TT, ACE DD and PAI-1 4G/4G was equivalent to that of the reference population. In addition, none of the analyzed phenotypical or genotypical parameters, except for the haptoglobin 2.2 phenotype, could be associated with the existence of a previous adverse CV event.(1) The clinical characteristics of the ESRD patients entering dialysis in our region were comparable to the currently observed dialysis populations in most European countries with the deleterious role of advancing age, diabetes, previous CVD, smoking and hypertension evident (2). Except for anemia therapy, there were no regional or national differences observed at dialysis start. (3) An analysis of the phenotypic and genotypic CV risk factors demonstrated differences with the reference population only for hyperhomocysteinemia, Lp(a) and ApoE4 allele prevalence, with no notable differences among the participating centers.

Dehydrated hereditary stomatocytosis (DHS) is a rare congenital hemolytic anemia. We observed that some patients had presented with different prenatal or perinatal forms of edema in some kindreds. Within weeks or months after birth, these exhibited a spontaneous, complete and definitive resorption. We assumed that some DHS patients, who were born without edema before ultrasound was available, might nonetheless have exhibited this during the prenatal period. The present report follows up the first pregnancy in a woman with overt DHS, but not herself having a known history of perinatal effusions. Ultrasound revealed that the fetus displayed ascites that disappeared prior to birth. The neonate had DHS. Prenatal edema must therefore be more frequent in DHS than known until now. DHS is another cause of prenatal edema to be considered in the differential diagnosis.

We read with interest the recently published paper by Carrier et al. [1] on the use of D-dimer (DD) in the elderly. This study demonstrates that the combination of a low Wells pre-test probability with a negative DD value safely excludes deep vein thrombosis (DVT) in elderly patients (aged over 60 years). However, the results of this study, based on pooled results of three technically different DD assays, are not totally in agreement with three other studies [2–4], and the authors suggest that this discrepancy might be explained by differences in the specificity of the DD assays. DD assays have been extensively evaluated, and meta-analyses were recently performed to determine the best tests [5,6]. One limitation of these approaches is that the findings are mainly based on an indirect comparison of the test performance from various studies and hence, mostly from heterogeneous patient populations. In the study, we compared performances in two rapid quantitative automatedDDassays on the same population and demonstrated that age was the main clinical characteristic related to discordant results between the two tests. We previously published a management study of 1134 consecutive non-selected patients clinically suspected of pulmonary embolism (PE) [7]. In this study, DD (cut-off 0.5 mg L, quantitative ELISA test, Vidas D-Dimer; BioMerieux, Lyon, France): (V) was determined straight away for 656 patients who fulfilled the criteria of our decision-making. For 608 of these patients, citrated plasma was immediately stored at )80 C, and a second DD measurement performed retrospectively using a rapid immunoturbidimetric assay (cutoff 0.5 mg L, STA-Liatest D-DI; Stago, Paris, France): (L). Data were complete for 603 patients (five patients were lost at follow-up) who achieved a 3-month follow-up. DDwere found negative (

Leukocyte infiltration inside glomeruli necessitates basement membrane collagen i.v. breakdown and leads to mesangiolysis, cell proliferation and extracellular matrix synthesis during the repair process as observed in the course of acute glomerulonephritis, vasculitis and acute graft rejection. Two matrix metalloproteinases, MMP-2 and MMP-9 gelatinases, are expressed and co-secreted in balance with the tissue inhibitor of metalloproteinases-1 (TIMP-1) by activated neutrophils as well as by glomerular cells and are aimed to control basement membrane collage i.v. deposition. Using a conventional double mesh sieving method, pure populations of glomeruli were isolated from fresh human cortex specimen and maintained in short-term cultures. ELISA, zymography and immunoblotting of conditioned serum-free media revealed glomerular MMP-2, MMP-9 and TIMP-1 secretion and activity while reverse transcription-polymerase chain reaction amplification of cellular RNA demonstrated glomerular transcripts coding for these enzymes and their inhibitor. When purified neutrophils were allowed to adhere onto Transwell apparatus in contact with glomerular suspensions, neutrophil 92 kDa gelatinase seemed apparently inhibited mainly because the production of TIMP-1 was enhanced on both sides of the insert. Glomerular 72 kDa and 92 kDa gelatinases were activated shortly (1 to 6 h) after neutrophils had interacted with glomeruli and furthermore upon activation by inflammatory or vasoactive mediators such as phorbol. Decreased neutrophil MMP-9 activity together with reduced MMP-9 mRNA levels and protracted TIMP-1 transcription and secretion during cell-cell interaction could participate to cell detachment from degraded basement membranes and to increased collagen i.v. deposition leading to glomerulosclerosis after initial glomerular injury by inflammatory cells.