{"id":3420,"date":"2006-04-13T21:22:36","date_gmt":"2006-04-13T20:22:36","guid":{"rendered":"http:\/\/moomango.co.uk\/htb\/?p=3420"},"modified":"2013-12-06T19:42:42","modified_gmt":"2013-12-06T19:42:42","slug":"association-between-hiv-subtype-and-detection-of-k103n","status":"publish","type":"post","link":"https:\/\/i-base.info\/htb\/3420","title":{"rendered":"Association between HIV subtype and detection of K103N"},"content":{"rendered":"

Polly Clayden, HIV i-Base<\/strong><\/p>\n

In a previous study Susan Eshleman\u0092s group analysed nevirapine resistance, at 6-8 weeks after receiving single dose nevirapine, in women with subtype C from the NVAZ trial, Malawi, and subtypes A and D from the HIVNET 012 trial, Uganda using the ViroSeq HIV-1 Genotyping System<\/strong> [1].<\/p>\n

The authors found that nevirapine resistance was lowest for subtype A and highest for subtype C. The most common NVP-resistance mutation in all three subtypes was K103N.<\/p>\n

A poster from Tamara S.Flys presented further analysis using a sensitive and quantitative point mutation assay, LigAmp to compare the level and prevalence of K103N containing variants in women with subtypes A,C and D at 6-8 weeks after receiving single dose nevirapine [2]. The assay cutoff for detection of K103N was 0.5%.<\/p>\n

Samples from 238 women were evaluated: 144 subtype A and 94 subtype D from HIVNET 012 and 63 subtype C from NVAZ.<\/p>\n

The authors found that the proportion of women with K103N was lowest for subtype A and highest for C (A, 60\/144 (41.7%); C, 44\/63 (69.8%); D, 51\/94 (54.3%); A vs C, p <0.0001; A vs D, p= 0.06; C vs D, p= 0.07). In a multivariate model, detection of K103N was independently associated with a higher delivery viral load (OR = 2.69, 95%CI 1.89 to 3.84) and subtype (C>A, OR = 2.48, 95%CI 1.24 to 4.93; D>A, OR = 1.71, 95%CI 0.94 to 3.11), but not with age or parity. Fewer days between receiving the single dose nevirapine and the 6-8 week visit was also significantly associated with the detection of K103N (OR=3.24, 95% CI 1.89-3.84)<\/p>\n

Among those women who had detectable K103N, the median percentage of K103N was lower for subtype A (2.22%) than for C (11.8%, p= 0.0007) or D (4.95%, p= 0.06). In a multivariate model, a higher level of K103N-containing variants (log10 % K103N) was associated with HIV subtype (C>A, p= 0.0001, \u0760 = 0.46, 95%CI 0.23 to 0.68; D>A: p= 0.02, \u0760= 0.27, 95%CI 0.05 to 0.49; C vs D, no difference, p= 0.12), but age (p= 0.70), parity (p= 0.62), the number of days between NVP dosing and the 6-8 week visit (p= 0.10), and delivery viral load (p= 0.46) were not.<\/p>\n

The authors wrote: \u0093We found a significant association between HIV-1 subtype and detection of K103N for subtype C vs A. The portion of women with K103N detected was also higher for subtype C than D, and for subtype D than A, but these differences were not statistically significant.\u0094 Additionally, \u0093 In a multivariate analysis, restricted to women with >\/= 0.5% K103N-containing variants, a higher level of K103N containing variants was associated with HIV subtype for both C>A and D>A.\u0094<\/p>\n

References:<\/p>\n

    \n
  1. Eshleman SH, Hoover DR, Chen C et al. Nevirapine resistance in women with HIV-1 subtype C compared with subtypes A and D, after the administration of single-dose nevirapine. JID, 192:30-36; 2005.<\/li>\n
  2. Flys TS, Chen S, Jones D et al. Analysis of K103N-containing HIV-1 variants in women with HIV-1 subtypes A, C, and D after single-dose nevirapine using a sensitive and quantitative point mutation assay. 13th CROI, Denver, 2006. Abstract 726.<\/li>\n<\/ol>\n","protected":false},"excerpt":{"rendered":"

    Polly Clayden, HIV i-Base In a previous study Susan Eshleman\u0092s group analysed nevirapine resistance, at 6-8 weeks after receiving single dose nevirapine, in women with subtype C from the NVAZ trial, Malawi, and subtypes A and D from the HIVNET …<\/p>\n","protected":false},"author":4,"featured_media":0,"comment_status":"closed","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[4,35,36],"tags":[60],"class_list":["post-3420","post","type-post","status-publish","format-standard","hentry","category-conference-reports","category-pmtct-and-maternal-health","category-drug-resistance","tag-croi-2006"],"_links":{"self":[{"href":"https:\/\/i-base.info\/htb\/wp-json\/wp\/v2\/posts\/3420","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/i-base.info\/htb\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/i-base.info\/htb\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/i-base.info\/htb\/wp-json\/wp\/v2\/users\/4"}],"replies":[{"embeddable":true,"href":"https:\/\/i-base.info\/htb\/wp-json\/wp\/v2\/comments?post=3420"}],"version-history":[{"count":0,"href":"https:\/\/i-base.info\/htb\/wp-json\/wp\/v2\/posts\/3420\/revisions"}],"wp:attachment":[{"href":"https:\/\/i-base.info\/htb\/wp-json\/wp\/v2\/media?parent=3420"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/i-base.info\/htb\/wp-json\/wp\/v2\/categories?post=3420"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/i-base.info\/htb\/wp-json\/wp\/v2\/tags?post=3420"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}