[Human immunodeficiency virus type 1 subtypes in Djibouti]. / Sous-types du virus de l'immunodéficience humaine de type 1 a Djibouti.

The authors had for aim to study the distribution of HIV-1 subtypes in a cohort of HIV positive patients in the hospital General Peltier of Djibouti. An epidemiological study was made on 40 HIV-1 positive patients followed up in the Infectious Diseases Department over three months. All patients sample were subtyped by genotyping. Thirty-five patients (15 men and 20 women) were found infected by an HIV-1 strain belonging to the M group. Genotyping revealed that - 66% of samples were infected with subtype C, 20% with CRF02_AG, 8.5% with B, 2.9% with CRF02_AG/C and 2.9% with K/C. In fact, Subtype C prevalence has been described in the Horn of Africa and a similar prevalence was previously reported in Djibouti. However our study describes the subtype B in Djibouti for the first time. It is the predominant subtype in the Western world. The detection of CRF02_AG strains indicates that they are still circulating in Djibouti, the only country in East Africa in which this recombinant virus was found. CRF02_AG recombinant isolates were primarily described in West and Central Africa. The presence of this viral heterogeneity, probably coming from the mixing of populations in Djibouti, which is an essential economic and geographical crossroads, incites us to vigilance in the surveillance of this infection.

Analysis of newly detected mutations in the MCFD2 gene giving rise to combined deficiency of coagulation factors V and VIII.

Combined deficiency of coagulation factor V (FV) and factor VIII (FVIII) (F5F8D) is a rare autosomal recessive disorder characterized by mild-to-moderate bleeding and reduction in FV and FVIII levels in plasma. F5F8D is caused by mutations in one of two different genes, LMAN1 and MCFD2, which encode proteins that form a complex involved in the transport of FV and FVIII from the endoplasmic reticulum to the Golgi apparatus. Here, we report the identification of a novel mutation Asp89Asn in the MCFD2 gene in a Tunisian patient. In the encoded protein, this mutation causes substitution of a negatively charged aspartate, involved in several structurally important interactions, to an uncharged asparagine. To elucidate the structural effect of this mutation, we performed circular dichroism (CD) analysis of secondary structure and stability. In addition, CD analysis was performed on two missense mutations found in previously reported F5F8D patients. Our results show that all analysed mutant variants give rise to destabilized proteins and highlight the importance of a structurally intact and functional MCFD2 for the efficient secretion of coagulation factors V and VIII.

Molecular analysis in two Tunisian families with combined factor V and factor VIII deficiency.

SUMMARY: Combined factor V (FV) and factor VIII (FVIII) deficiency (F5F8D) is a rare autosomal recessive disorder caused by mutations in LMAN1 or MCFD2 genes which encode proteins that form a complex involved in the transport of FV and FVIII from the endoplasmic reticulum to Golgi apparatus. We report two novel mutations in MCFD2 gene and one recurrent mutation in LMAN1 gene that caused combined FV and FVIII deficiency in two unrelated Tunisian Muslim families. For the first family two patients were homozygous for a new missense mutation Asp81His in exon 3 of MCFD2 and heterozygous for a second new missense mutation Val100Asp in the same exon. Replacement respectively of the hydrophilic Asp residue with hydrophobic positively charged His and of the hydrophobic neutral Val residue with the Asp residue most likely disrupts the MCFD2-LMAN1 interaction, thus leading to the disease phenotype. For the second family a reported Arg202X mutation in exon 5 in the LMAN1 gene was identified in the homozygous state.

[Effects of prolonged exposure to antiretroviral treatment in Tunisian patients assessed by the HIV-1 resistance genotypic test]. / Effets de l'exposition prolongée au traitement chez des patients tunisiens, évalués par le test génotypique de résistance du VIH-1.

SETTINGS: In Tunisia, therapeutic failure profile is detected in 42.22% of treated patients. These patients are still confronted to ethical and socioeconomic problems but also to therapeutic and technical ones. Indeed, the limited number of available antiretroviral (ARV) molecules and the unavailability of resistance genotypic test in routine use is the reason why the same therapeutic combination of ARV molecules is maintained after therapeutic failure in some cases. OBJECTIVE AND METHOD: The authors studied the evolution, on two consecutive samples, of resistance mutations in patients with prolonged exposure to the same therapeutic combination after therapeutic failure and the resulting effect on management of these patients. RESULTS: We found a greater number of patients presenting with mutant viral stains after a prolonged exposure to the same ARV molecules. Results also showed that the detected mutation frequency increased and even more on the second sample, compared to the first one. Thus, the early diagnostic of resistance mutations using genotypic resistance test would be of great interest by allowing the physician to take necessary measures to reduce resistance rate and find an optimal treatment for the patient. CONCLUSION: The introduction of new ARV molecules in our country was also an important step by improving the therapeutic management of HIV infected patients.

Profile of drug resistance mutations among HIV-1-infected Tunisian subjects failing antiretroviral therapy.

Three years after the introduction of antiretroviral therapy (ART) in Tunisia (North Africa), we aimed to determine the prevalence of drug resistance mutations in Tunisian HIV-1-infected patients failing ART. Plasma samples of 80 patients were tested for genotypic resistance using two distinct line probe assays, LiPA HIV-1 reverse transcriptase RT and LiPA HIV-1 protease assay. Of the 80 patients, 82.5% showed resistance to at least one antiretroviral molecule. In the RT gene, resistance to nucleoside RT inhibitors (NRTIs) and non-nucleoside RT inhibitors (NNRTIs) were recognized in 66.25 and 37.5%, respectively, with M184V, T215Y and K103N being the codons most frequently involved. Resistance to protease inhibitors (PIs) was found in 46.25% of cases. Despite the presence of different mutations, the viral variants were still susceptible to other RTIs and PIs that are currently not available in Tunisia. Thus, alternative therapeutic options exist but are not yet accessible.