Vol. 1, Issue 1, Part A (2019)

Context: Easily applicable, the Dried Blood Spot (DBS) makes it possible to collect blood drawn from a tube or by pricking in the heel or finger, both in town and in decentralized regions. They allow samples to be stored at room temperature or cold, in airtight bags to prevent humidity. Objective: The aim of this work was to determine the correlation between the results of sequencing on liquid plasma and on DBS in N’Djamena, Chad. Methods: The blood of 50 patients living with HIV was drawn on a tube with EDTA and 30 of them were randomly put on Whatman ® 903 type DBS. The drying was done overnight at room temperature. Storage was done at -20 ° C. Viral RNA extraction was performed with the QiAamp Viral RNA mini kit. The viral load on DBS and on plasma was carried out at LRS CHU-ULg. The determination of the variants was obtained after analysis on the Stanford University/HIV Drug Resistance Database site. The interpretation of the resistances is made in accordance with the algorithm of the ANRS AC11. Results: An amplification rate of 80% is obtained on the DBS with a detection limit of the blotter is 3.33 log₁₀ copies of RNA/ml. The subtypes obtained on the Protease sequences, which is the least changing region of the virus were retained. CRF02_AG is the most represented both on DBS with 29.17% and on plasma with 30.23%. Sequencing on DBS showed the presence of the K subtype (12.5%) at the level of the Reverse Transcriptase while it is absent in the plasma after sequencing. Conclusion: An amplification success rate of 80% compared to plasma was observed in this study. However, DBS can be useful for the evaluation of antiretroviral therapy for non-B subtypes.