HIV-1 drug resistance surveillance using dried whole blood spots

Abstract

Background Field-friendly methods for HIV drug resistance (HIVDR) surveillance in resource-limited regions are urgently needed. Despite evidence that dried blood spots (DBS) are suitable for HIV serology, viral load and CD4+ T-cell enumeration, no study has evaluated DBS for HIVDR genotyping. We assessed the feasibility of genotyping HIV-1 from field-collected DBS stored under challenging environmental conditions. Methods We prospectively collected specimens from newly diagnosed, treatment-naive HIV-positive subjects in Mexico. Whole blood was spotted onto filter cards, air dried at ambient temperature and stored with desiccant at 37°C and 85% humidity for 3 months. Genotypes obtained from DBS-extracted nucleic acids using an in-house nested reverse transcription-PCR method were compared to genotypes derived from matched plasma. Results Genotypes from 103 phylogenetically matched plasma and DBS were compared. In total, 90.1% of all DBS specimens could be amplified in either the region of HIV protease or the region of reverse transcriptase. Failure to amplify from DBS did not correlate with low plasma viral loads. Between paired specimens, the median nucleotide similarity was 99.95%. In the nine specimens with drug resistance mutations, all differences between pairs were partial discordances. Mutations identified in plasma were found in the majority of replicate DBS amplifications. Conclusion The results suggest that genotypes obtained from DBS are equivalent to those from plasma. DBS are a promising public health tool for HIVDR surveillance of treatment-naive subjects, especially in regions where specimens might be exposed to severe environmental conditions and where logistical difficulties could prevent timely specimen processing. More studies are needed to validate DBS for patient monitoring.

Rapid decline in the efficiency of HIV drug resistance genotyping from dried blood spots (DBS) and dried plasma spots (DPS) stored at 37 C and high humidity

“…8,10 Higher amplification efficiencies than those reported here have also been noted upon storage at 378C but lower (85%) humidity conditions for up to 3 months although the study amplified smaller 700 bp pol fragments. 11 Our study shows that even in the presence of desiccant, the window of opportunity to genotype specimens exposed to extreme conditions is short. However, our design did not contemplate changes in desiccant, which may be advisable upon evidence of moisture.…”

Evaluation of the Dried Blood Spot (DBS) Collection Method as a Tool for Detection of HIV Ag/Ab, HBsAg, anti-HBs and anti-HCV in a Malaysian Tertiary Referral Hospital

“…[5][6][7][8][9][10][11][12][13][14][15] These studies prove that DBS/DPS sampling is effective for the detection of HIV-1 p24 antigen 5 and of HIV-1 DNA, 6,7 for serotyping, 8,9 for quantifi cation of HIV-1 RNA, 6,[10][11][12] for genotyping 13 and for the monitoring of drug resistance. [14][15][16][17][18] DBS collection is easy-to-perform, requires minimal training, and it obviates the risks associated with the use and disposal of syringes and needles. Some viruses such as HIV-1, HIV-2, human T-cell lymphotropic virus (HTLV) and hepatitis C virus lose their infectivity upon drying, hence DBS represents a low infectious hazard.…”

HIV-1 drug resistance genotyping success rates and correlates of Dried-blood spots and plasma specimen genotyping failure in a resource-limited setting

“…This probably arose from the large proportion of DBS specimens originating from routine clinical diagnosis that face significant challenges in terms of specimen collection, transportation, and storage. Moreover, DBS have considerably gained preference to plasma because DBS specimens are easy to collect, transport and do not require a cold chain [ 22 , 40 ]. This explains why we received more DBS than plasma specimens between 2017 and 2019.…”