Angiotensin-Converting Enzyme Inhibitor-Associated Angioedema: From Bed to Bench.

BACKGROUND AND OBJECTIVE: Angiotensin-converting enzyme inhibitor-associated angioedema (ACEI-AAE) affects 0.1%-0.7% of patients treated with ACEIs. While previous research suggests that angioedema attacks result from increased vascular permeability, the pathogenesis is not completely understood. Objective: This study aimed to describe the clinical, genetic, and laboratory parameters of ACEI-AAE patients and to investigate the role of vascular endothelial growth factors A and C (VEGF-A and VEGF-C), angiopoietins 1 and 2 (Ang1/Ang2), and secretory phospholipase A2 (sPLA2) in the pathogenesis of ACEI-AAE. METHODS: The clinical and laboratory data of ACEI-AAE patients were collected from 2 angioedema reference centers. Healthy volunteers and ACEI-treated patients without angioedema were enrolled to compare laboratory parameters. Genetic analyses to detect mutations in the genes SERPING1, ANGPT1, PLG, and F12 were performed in a subset of patients. RESULTS: A total of 51 patients (57% male) were diagnosed with ACEI-AAE. The average time to onset of symptoms from the start of ACEI therapy was 3 years (range, 30 days-20 years). The most commonly affected sites were the lips (74.5%), tongue (51.9%), and face (41.2%). Switching from ACEIs to sartans was not associated with an increased risk of angioedema in patients with a history of ACEIAAE. VEGF-A, VEGF-C, and sPLA2 plasma levels were higher in ACEI-AAE patients than in the controls. Ang1/2 concentrations remained unchanged. No mutations were detected in the genes analyzed. CONCLUSIONS: Our data suggest that sartans are a safe therapeutic alternative in ACEI-AAE patients. Increased concentrations of VEGF-A, VEGF-C, and sPLA2 in ACEI-AAE patients suggest a possible role of these mediators in the pathogenesis of ACEI-AAE.

A New SERPINA-1 Missense Mutation Associated with Alpha-1 Antitrypsin Deficiency and Bronchiectasis.

Alpha-1-antitrypsin deficiency (AATD) is a genetic condition caused by SERPINA1 mutations, which culminates into lower protease inhibitor activity in the serum and predisposes to emphysema. Clinical manifestations of AATD are often associated to ZZ (p.Glu342Lys) and SZ (p.Glu264Val) genotypes and less frequently to rare deficiency or null alleles in heterozygous and homozygous states. We report a case of a 52-year-old woman with bronchiectasis without other potential causes other than an electrophoresis that showed a decrease of alpha-1 globin band and AAT levels below the normal value (78 mg/dl; v.n. 90-200 mg/dl). No S or Z mutation was identified, but sequencing analysis found a novel missense variant Ile74Asn (c.221T > A) in heterozygous state on an M3 allele (Glu400Asp) in the exon 2 of the SERPINA-1gene, probably leading to a dysfunctional protein. This mutation has never been previously identified, and it is interesting to note the association with bronchiectasis in the absence of emphysema.

The M2 haplotype in the ANXA5 gene is an independent risk factor for idiopathic small-for-gestational age newborns.

Hereditary thrombophilias can impair vascular placental functions and predispose to the birth of small-for-gestational age (SGA) babies. The placental anticoagulant protein annexin A5 (ANXA5) may contribute to this process. A functional haplotype (M2) within the ANXA5 gene is associated with fetal loss and venous thrombosis. This study investigated the prevalence of the M2 haplotype in a group of women with idiopathic SGA newborn babies. Seventy-eight women with at least one previous unexplained SGA birth and 195 controls all from Southern Italy were investigated. Hereditary thrombophilia was found in 13 (16.5%) cases and 21 (11%) controls (P < 0.05.). The M2 haplotype was found in 29% of cases (n = 23) and 15% of controls [n = 30; P = 0.001; OR = 2.3, 95% CI (1.17-4.48)]. Within the case group, 82.5% of the M2 haplotype carriers gave birth to babies with a birthweight below the 3rd percentile [P = 0.01; OR = 2.4, 95% CI (1.26-4.73)]. A logistic regression, corrected for age, parity and gravity showed that the M2 haplotype was independently associated with the delivery of an SGA new born [P = 0.029; OR = 2.6, 95% CI (1.1-6.0)]. In conclusion, the M2 haplotype of the ANXA5 gene confers a risk of delivering SGA babies.

Polymorphic miRNA-mediated gene contribution to inhibitor development in haemophilia A.

Development of inhibitory antibodies is perhaps the most serious complication of FVIII replacement therapy, precluding efficient clinical management of patients with haemophilia A (HA). The development and function of immune system are also regulated by microRNAs (miRNAs). Mutations and changes in the level of expression of some miRNA genes have been associated with the onset and progression of immunological disorders. The aim of this study was to investigate new genetic polymorphisms in loci for miRNA and their targets to evaluate whether these SNPs may confer susceptibility to inhibitor development in patients with HA. Italian HA patients with and without inhibitors and healthy controls were recruited in this study. For SNP analysis, standard DNA sequencing method was used. We have studied four SNPs, i.e. rs36101366, rs34683807, rs1803603 and rs3024496 located in the 3'UTR of F8 and IL-10 genes. These SNPs have been checked for their frequencies in patients with and without inhibitors, but no statistically significant differences were found. Then, we have searched for other genetic variants in loci for haematopoietic-specific miRNAs, i.e. hsa-mir-150, hsa-mir-155, hsa-mir-146a, hsa-mir-142, hsa-mir-181a and in a specific miRNA, hsa-mir-1184, i.e. predicted to be located in the intron 22 of F8 gene. For all miRNAs selected, we did not identify any sequence variation in our study population. This is the first study to demonstrate that there was no association between selected SNPs in miRNAs and their targets and the susceptibility to inhibitor development in people affected by HA.

Subclinical atherosclerosis and genetic risk markers in healthy offspring of patients with premature myocardial infarction.

AIM: Healthy young subjects with parental history of premature myocardial infarction (PHPMI) might constitute a privileged population for the study of genetic risk markers (GRM) for atherosclerosis. Aim of this study was to evaluate which, if any, GRM atherosclerosis-associated in previous studies has increased prevalence in a selected population. METHODS: Twenty-four healthy young subjects (12 males and 12 females; mean age 18.0±8.0 years) with PHPMI and 24 age- (±1 year), sex-matched healthy subjects without PHPMI were enrolled in the study. They underwent: 1) fasting measurement of lipid profile, resting blood pressure and body mass index; 2) high resolution B-mode ultrasonographic evaluation of common carotid artery intima-media thickness (IMT); 3) evaluation of Single Nucleotide Polymorphisms (SNPs) for six candidate genes associated with preclinical atherosclerosis. RESULTS: Compared to controls, subjects with PHPMI had increased IMT of common carotid arteries (mean of combined sites: 0.535±0.171 mm versus 0.432± 0.133 mm in controls, P=0.017). Offspring of coronary patients showed an increased prevalence of the unfavourable chemochine (C-X-C motif) ligand 12 (CXCL12) SNP risk genotype (P=0.047). CONCLUSION: In healthy young subjects with PHPMI there is an increased prevalence of the unfavorable CXCL12 SNP risk genotype.

Familial X;Y translocation with distinct phenotypic consequences: Characterization using FISH and array CGH.

X;Y translocation is a relatively rare event in humans. Analyzed cytogenetically, the majority of these aberrations have breakpoints at Xp22 and Yq11. Females with t(X;Y)(p22;q11) are phenotypically normal except for short stature, while the males may have abnormalities. Aberrations that lead to nullisomy of the deleted region and complete loss of the respective genes have been recognized as a cause of variable contiguous gene syndromes in males. The phenotype depends on the extent and position of the deletion showing the variable association of apparently unrelated clinical manifestations such as ichthyosis, chondrodysplasia punctata, hypogonadotropic hypogonadism with anosmia, ocular albinism, short stature, and mental retardation. In addition, some patients have been reported with symptoms of attention deficit hyperactivity disorder. The extent of terminal Xp deletions is limited by the presence of male lethal genes in Xp22.2 at about 10-11 Mb from the telomere. The deletions in the majority of viable reported male patients extend to the STS ( approximately 7.0 Mb) or to the KAL1 ( approximately 8.5 Mb) loci. We present a clinical, cytogenetic, FISH, and array CGH study of a family with an Xp;Yq translocation. The chromosomal status is also discussed in the light of their phenotypic traits. The final karyotypes of the patients were designated as: Patient 1: 46,Y,der(X),t(X;Y)(p22;q12).ish der(X)(Xpter-,DXZ1+,Xqter+)mat.arr cgh Xp22.31p22.33(RP11-60P14 --> RP13-391G2)x0;arr cgh Yq11.221qter (RP11-235I1 --> RP11-270H4)x2.Patient 2: 46,X,der(X),t(X;Y)(p22;q12).ish der(X)(Xpter-,DXZ1+,Xqter+)mat.arr cgh Xp22.31p22.33(RP11-60P14 --> RP13-391G2)x1;arr cgh Yq11.221qter (RP11-235I1 --> RP11-270H4)x1.

Polymorphisms in genes involved in autoimmune disease and the risk of FVIII inhibitor development in Italian patients with haemophilia A.

One of the most severe and important complication in the treatment of patients with haemophilia A is the formation of neutralizing antibodies (FVIII inhibitors) that inhibit the clotting activity of substituted FVIII. Both genetic and environmental factors influence the susceptibility of patients to develop inhibitors. The objective of this study was to evaluate whether polymorphisms in different genes involved in the regulation of the immune system may confer susceptibility to inhibitor development in patients with HA. We analysed the distribution of polymorphisms in the CTLA4, PTPN22, IL10, TNFalpha, FOXP3 and IRF5 genes that have been reported to be associated with a number of autoimmune disease. In addition, we evaluated the distribution of IL10 haplotypes in haemophilic patients and healthy controls to assess whether specific polymorphisms in IL10 gene were associated to the risk of inhibitor development. We focused on a cohort of Italian unrelated haemophilic patients with and without a history of inhibitors. Genotyping was carried out with standard methods including RFLP, real time PCR and direct DNA sequencing. Our data show that, considering single nucleotide variations, genotype frequencies in patients with inhibitors were not significantly different from those observed in patients without inhibitors, suggesting a lack of association between these polymorphisms and the development of inhibitors. Moreover, no relationship was found between specific combinations of IL10 alleles and the antibody production. Previous contradictory association studies may depend on the different genetic background of the population examined. Further studies may contribute to a clearer understanding of this process.

Factor XI deficiency: two novel mutations in asymptomatic Italian patients.

SUMMARY: Factor XI (FXI) deficiency is a rare bleeding disorder, resulting in a wide range of bleeding manifestations, from asymptomatic bleeding to injury-related bleeding. To identify mutations in FXI-deficient patients and to establish a possible relationship between clinical phenotype and genotype, we studied two patients from Southern Italy with FXI deficiency. They were identified by presurgical or routine laboratory screening. None of them showed bleeding. Three different mutations were detected (Glu117Stop, Cys118Arg and Trp497Gly); two of them were novel (Cys118Arg and Trp497Gly). One patient (with severe FXI levels) showed a compound heterozygosity (Glu117Stop with Cys118Arg). Two novel missense mutations were highly conserved among different species. In our patients, bleeding tendency did not appear to be correlated with FXI levels or with a single mutation in heterozygosis. On the other hand, the compound heterozygosis might explain low FXI levels, but it is not associated with bleeding. Our data confirm that a severe FXI deficiency is not necessarily associated with bleeding.

Coexistence of mutations in PINK1 and mitochondrial DNA in early onset parkinsonism.

AIMS AND BACKGROUND: Various genes have been identified for monogenic disorders resembling Parkinson's disease. The products of some of these genes are associated with mitochondria and have been implicated in cellular protection against oxidative damage. In the present study we analysed fibroblasts from a patient carrying the homozygous mutation p.W437X in the PTEN-induced kinase 1 (PINK1), which manifested a very early onset parkinsonism. RESULTS: Patient's fibroblasts did not show variation in the mtDNA copy number or in the expression of the oxidative phosphorylation complexes. Sequence analysis of the patient's mtDNA presented two new missense mutations in the ND5 (m.12397A>G, p.T21A) and ND6 (m. 14319T>C, p.N119D) genes coding for two subunits of complex I. The two mutations were homoplasmic in both the patient and the patient's mother. Patient's fibroblasts resulted in enhanced constitutive production of the superoxide anion radical that was abrogated by inhibitor of the complex I. Moreover enzyme kinetic analysis of the NADH:ubiquinone oxidoreductase showed changes in the substrates affinity. CONCLUSION: To our knowledge, this is the first report showing co-segregation of a Parkinson's disease related nuclear gene mutation with mtDNA mutation(s). Our observation might shed light on the clinical heterogeneity of the hereditary cases of Parkinson's disease, highlighting the hitherto unappreciated impact of coexisting mtDNA mutations in determining the development and the clinical course of the disease.

Association of plasminogen activator inhibitor (PAI)-1 (SERPINE1) SNPs with myocardial infarction, plasma PAI-1, and metabolic parameters: the HIFMECH study.

OBJECTIVE: The purpose of this study was to investigate the effects of plasminogen activator inhibitor-1 (PAI-1) gene (SERPINE1) single nucleotide polymorphisms (SNPs) on the risk of myocardial infarction (MI), on PAI-1 levels, and factors related to the metabolic syndrome. METHODS AND RESULTS: Eleven SNPs capturing the common genetic variation of the SERPINE1 gene were genotyped in the HIFMECH study. In the 510 male cases and their 543 age-matched controls, a significant gene-smoking interaction was observed. In nonsmokers, the rs7242-G allele was more frequent in cases than in controls (0.486 versus 0.382, P=0.013) whereas the haplotype derived from the rs2227631 (-844A>G)-G and rs2227683-A alleles was approximately 3-fold lower in cases than in controls (0.042 versus 0.115, P=0.006). SERPINE1 haplotypes explained 3.5% (P=0.007) of the variability of PAI-1 levels, which was attributable to the combined effects of 3 SNPs, -844A>G, rs2227666, and rs2227694. The rs6092 (Ala15Thr) and rs7242 SNPs acted additively to explain 4.4% of the variability of plasma insulin levels and 1.6% of the variability of BMI (P<10(-3) and P=0.023, respectively). CONCLUSIONS: SERPINE1 haplotypes are mildly associated with plasma levels of PAI-1 and with the risk of MI in nonsmokers. They are also associated with insulin levels and BMI.

[Anticoagulant prophylaxis in women affected by thrombophilia and previous obstetric complications]. / Profilassi antitrombotica in donne con diagnosi di trombofilia e precedenti complicanze ostetriche.

Pregnancy is a condition of excessive clotting due to a decrease of some coagulation factors and a reduction of anticoagulant proteins, such as protein S. It is known that the causes of congenital or acquired thrombophilia may be associated with an increased risk of venous thromboembolism during pregnancy and/or obstetric complications, such early or late fetal loss, intrauterine fetal deaths, pre-eclampsia, fetal growth restriction. During pregnancy the use of a prophylaxis with antithrombotic drugs is considered at present a promising opportunity to significantly reduce the prevalence of thromboembolic complications, improving maternal and fetal outcomes. This article is a review to most recent evidence of pregnant anticoagulant prophylaxis in women with previous thromboembolic events.

Identification of FVIII gene mutations in patients with hemophilia A using new combinatorial sequencing by hybridization.

BACKGROUND: Standard methods of mutation detection are time consuming in Hemophilia A (HA) rendering their application unavailable in some analysis such as prenatal diagnosis. OBJECTIVES: To evaluate the feasibility of combinatorial sequencing-by-hybridization (cSBH) as an alternative and reliable tool for mutation detection in FVIII gene. PATIENTS/METHODS: We have applied a new method of cSBH that uses two different colors for detection of multiple point mutations in the FVIII gene. The 26 exons encompassing the HA gene were analyzed in 7 newly diagnosed Italian patients and in 19 previously characterized individuals with FVIII deficiency. RESULTS: Data show that, when solution-phase TAMRA and QUASAR labeled 5-mer oligonucleotide sets mixed with unlabeled target PCR templates are co-hybridized in the presence of DNA ligase to universal 6-mer oligonucleotide probe-based arrays, a number of mutations can be successfully detected. The technique was reliable also in identifying a mutant FVIII allele in an obligate heterozygote. A novel missense mutation (Leu1843Thr) in exon 16 and three novel neutral polymorphisms are presented with an updated protocol for 2-color cSBH. CONCLUSIONS: cSBH is a reliable tool for mutation detection in FVIII gene and may represent a complementary method for the genetic screening of HA patients.

Abnormally high thromboxane biosynthesis in homozygous homocystinuria. Evidence for platelet involvement and probucol-sensitive mechanism.

Homocystinuria due to homozygous cystathionine beta-synthase deficiency is an inborn error of metabolism characterized by a high incidence of thrombosis and premature atherosclerosis. We evaluated TXA2 biosynthesis in vivo and several in vitro tests of platelet function in 11 homocystinuric patients and 12 healthy controls. In vitro, patients' platelet aggregation was within control values as were TXB2 formation, fibrinogen binding, and ATP secretion in response to thrombin. In contrast, the urinary excretion of 11-dehydro-TXB2, a major enzymatic derivative of TXA2, was > 2 SD of controls in all patients (1,724 +/- 828 pg/mg creatinine, mean +/- SD, in patients vs. 345 +/- 136 in controls, P < 0.001). The administration to four patients of low-dose aspirin (50 mg/d for 1 wk) reduced metabolite excretion by > 80%. The recovery of 11-dehydro-TXB2 excretion over the 10 d that followed aspirin cessation occurred with a pattern consistent with the entry into the circulation of platelets with intact cyclooxygenase activity. Prolonged partial reduction in the abnormally high excretion of both 11-dehydro-TXB2 and 2,3-dinor-TXB2, was also observed in seven patients who ingested 500 mg daily for 3 wk of the antioxidant drug probucol. These results provide evidence for enhanced thromboxane biosynthesis in homocystinuria and for its partial dependence on probucol-sensitive mechanisms. Furthermore, the elevated TXA2 formation in homocystinuria is likely to reflect, at least in part, in vivo platelet activation.

The JAK2 V617F mutation frequently occurs in patients with portal and mesenteric venous thrombosis.

BACKGROUND: Myeloproliferative disorders (MPDs) represent a risk factor for thrombosis in the portal, mesenteric, and hepatic districts. OBJECTIVE: We aimed to assess whether the Janus kinase 2 (JAK2) V617F mutation, an acquired mutation that occurs in MPD patients, is a risk factor for portal and mesenteric venous thrombosis (PMVT) independently of the presence of overt MPDs. PATIENTS AND METHODS: The medical histories of 99 patients presenting with PMVT were obtained. The presence of the JAK2 V617F and VHL 598C > T mutations was determined by polymerase chain reaction followed by restriction enzyme analysis and direct cycle sequence analysis. RESULTS: Over a 10-year period of observation, of the 99 patients presenting with PMVT, the JAK2 V617F mutation was detected in heterozygous state in 17 individuals [17.2%; 95% confidence interval (95% CI) 10.9-25.9]. None of the patients presenting with the JAK2 V617F mutation carried an inherited thrombophilic risk factor. Seven patients with (43.8%; 95% CI 19.8-70.1) and two without (2.4%; 95% CI 0.3-8.4) the JAK2 V617F mutation had a diagnosis of MPD at the occurrence of the venous thrombotic event. After a median follow-up of 41 months (range 3-114 months), three out of the 10 patients carrying the JAK2 V617F mutation were then diagnosed as having idiopathic myelofibrosis (n = 2) or polycythemia vera (n = 1), whereas in seven patients a MPD was not detected. Two of the 83 patients without the JAK2 V617F mutation went on to develop MPDs. CONCLUSIONS: Determination of the JAK2 V617F mutation may contribute to the search for genetic determinants of PMVT and may be useful to recognize patients who should be carefully observed for the subsequent development of overt MPDs.

The G20210A prothrombin variant and the risk of venous thromboembolism or fetal loss in pregnant women: a family study.

BACKGROUND: The relationship between the G20210A prothrombin variant (PT-G20210A) and adverse pregnancy outcome has been studied by several groups in the last few years. However, because of the different design and sample sizes of these studies the estimated risks have varied. OBJECTIVE: In this retrospective, multi-center, cohort study we assessed the risk of thromboembolic or obstetric complications in women belonging to families of probands with isolated PT-G20210A and that were symptomatic for venous thromboembolism (VTE). METHODS: Two hundred and eighty-three female family members that had been pregnant at least once were enrolled. The occurrence of VTE and obstetric complications during pregnancy and postpartum were assessed in carriers of PT-G20210A and compared with non- carriers. RESULTS: One thromboembolic event occurred during the postpartum period in the carriers group. In the same group, 48 out of 359 pregnancies resulted in unexplained fetal loss as compared with 50 out of 357 pregnancies in the non-carriers (RR 0.9; 95% CI: 0.7-1.4). After adjustment, carriers of PT-G20210A showed a trend towards a higher risk of late fetal loss as compared with non-carriers (RR 2.2; 95% CI: 0.8-6.2). Furthermore, in pregnancies subsequent to those with previous fetal loss there was not a different risk of adverse outcome regardless of the carrier status. CONCLUSIONS: Female family members who are heterozygous carriers of isolated PT-G20210A do not seem to be at significant increased risk for fetal loss as compared with non-carriers. Screening for PT-G20210A of fertile age women belonging to these families is not warranted in this situation.