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Abstract Inherited factor VII (FVII) deficiency is a rare disorder characterized by a bleeding phenotype varying from mild to severe. To date, more than 200 mutations have been described along the F7 gene encoding for FVII. The aim of this study was the identification of genetic defects underlying FVII deficiency in 10 patients belonging to eight unrelated families of the North provinces from Tunisia. Mutation detection was performed by sequencing the whole F7 gene coding region, exon-intron boundaries and about 400 bp of the promoter region. We identified 5 mutations in five unrelated families; the novel p.F328Y mutation and the reported mutations: p.R304Q, p.M298I, IVS1aG > A and p.G-39G. For the remaining 5 patients we didn’t identified any mutations using PCR/Sequencing protocol. In conclusion, this study represents the first comprehensive molecular series of FVII deficiency affected patients in Tunisia from the North. We will try in the future to continue the molecular study for Tunisian patients from Center and South provinces in order to have a complete idea about the FVII deficiency mutational profile in our country. Virtual slides The virtual slide(s) for this article can be found here: http://www.diagnosticpathology.diagnomx.eu/vs/1288044089753085

Abstract Introduction Hemophilia A is an X linked recessive hemorrhagic disorder caused by mutations in the F8 gene that lead to qualitative and/or quantitative deficiencies of coagulation factor VIII (FVIII). Molecular diagnosis of hemophilia A is challenging because of the high number of different causative mutations that are distributed throughout the large F8 gene. Molecular studies of these mutations are essential in order to reinforce our understanding of their pathogenic effect responsible for the disorder. Aim In this study we have performed molecular analysis of 28 Tunisian hemophilia A patients and analyzed the F8 mutation spectrum. Methods We screened the presence of intron 22 and intron 1 inversion in severe hemophilia A patients by southern blotting and polymerase chain reaction (PCR). Detection of point mutations was performed by dHPLC/sequencing of the coding F8 gene region. We predict the potential functional consequences of novel missense mutations with bioinformatics approaches and mapping of their spatial positions on the available FVIII 3D structure. Results We identified 23 different mutations in 28 Tunisian hemophilia A patients belonging to 22 unrelated families. The identified mutations included 5 intron 22 inversions, 7 insertions, 4 deletions and 7 substitutions. In total 18 point mutations were identified, of which 9 are located in exon 14, the most mutated exonic sequence in the F8 gene. Among the 23 mutations, 8 are novel and not deposited in the HAMSTeRS database nor described in recently published articles. Conclusion The mutation spectrum of Tunisian hemophilia A patients is heterogeneous with the presence of some characteristic features. Virtual slides The virtual slide(s) for this article can be found here: http://www.diagnosticpathology.diagnomx.eu/vs/1693269827490715

Abstract Background The development of inhibitors against factor 8 (F8) is the most serious complication of replacement therapy with F8 in children with severe hemophilia. It was suggested that mismatched F8 replacement therapy may be a risk factor for the development of anti-factor F8 alloantibodies. Recently four single nucleotide polymorphisms (SNPs) encoding six distinct haplotypes, designated H1 through H6, were studied in different populations. Two SNPs are components of the A2 and C2 immunodominant-inhibitor epitopes. The aim of this study is to determine the different types of haplotypes in relation with inhibitors developments and their frequencies in our Tunisian hemophiliac population. Materials and methods 95/116 Tunisian patients with hemophilia A undergoing treatment at Hemophilia Treatment Center, Aziza Othmana hospital, participate in this study. Among them only six patients develop inhibitors. The four SNPs were amplified and sequenced. Results and Discussion In a total of 77 patients, we identified the H1, H2, H3 and the infrequent H5 haplotypes. The H1 and H2 haplotypes, which have the same amino acid sequence in the recombinant F8 molecules used clinically, are the most represented with the frequency of 0.763 and 0.157 respectively. This distribution is almost similar to that of Caucasians in which the frequencies are respectively 0.926 and 0.074, whereas it is 0.354 and 0.374 among Subsaharians. Four patients with inhibitors studied here have the H1 haplotype. For one patient who has a large deletion including the exon 10 we can't identify his haplotype. Theses frequencies may explain partially the low level of inhibitors in our patients.

Background and Objectives: Plasma‐derived medicinal products (PDMPs) are essential to treat many chronic conditions such as haemophilia and primary immunodeficiency. Patients living in low middle‐income and low‐income countries (LMICs and LICs, respectively) have limited access to PDMPs. The aim of this article is to explore the challenges of accessing PDMPs in LMICs and LICs. Materials and Methods: A review of the literature and reports on blood safety, plasma production and its utilization to produce PDMPs in LMICs and LICs was carried out. Results: There is huge wastage of recovered plasma in LMICs and LICs as a result of a lack of good manufacturing practice (GMP) in the production of plasma for fractionation. Together with the high cost of imported PDMP procurement, patients have limited access to such products. Conclusion: There is a need to improve the situation by using domestically sourced plasma through the initiation of local plasma programmes through a stepwise approach to improve access to PDMPs in LMICs and LICs. [ABSTRACT FROM AUTHOR]

Despite the faster inhibitor eradication with high-dose ITI, a low-dose regimen has proven effective as well.6 We describe the experience of a low-dose regimen ITI with plasma-derived CFC in a real-world setting. Immune Tolerance Induction (ITI) remains the treatment of choice to achieve the latter goal.5 There are several ITI regimens, all of which involve frequent infusions of CFC to induce immune tolerance. Low-dose ITI is recommended in good-risk patients.5However, we opted for a low-dose regimen for all our patients, mainly due to cost effectiveness. Besides, evidence has shown that the low-dose ITI regimen is as effective as the high-dosing regimen.6 The I-ITI study showed that low-dose ITI takes longer to achieve immune tolerance and is associated with more bleedings.6 Regardless of the regimen, ITI should last no longer than 36 months.10 However, it was prolonged beyond 36 months in two patients. [Extracted from the article]