Evaluation of the Geenius HIV 1/2 confirmatory assay for HIV-2 samples isolated in Japan.

BACKGROUND: Although the number of HIV-2-infected individuals is quite low in Japan, at least three groups of HIV-2 (A, B and CRF01_AB) have been detected thus far. In particular, CRF01_AB HIV-2 cases have been found only in limited areas, Cote d'Ivoire and Japan. Here, we demonstrate that Geenius HIV 1/2 Confirmatory Assay (Geenius, Bio-Rad Laboratories) is able to detect HIV-2 samples, including groups A, B and CRF01_AB, isolated in Japan. STUDY DESIGN: A total of 57 plasma samples, including three panels (Ⅰ: HIV-2-positive samples [n=9], Ⅱ: HIV-1 infection with HIV-2 antibody cross-reactivity samples [n=37], and Ⅲ: HIV negative with biological false-positive HIV-2 samples [n=11]) were tested by Geenius. RESULTS: Geenius determined Panel I to be "HIV-2 positive with/without HIV-1 cross-reactivity (n=4, respectively)", including HIV-2 group A and CRF01_AB. In the case with HIV-2 group B, all bands were detected, resulting in a Geenius interpretation of "HIV positive untypable". Geenius classified Panels II and III as "HIV-1 positive (n=37)" or "HIV negative (n=9)", "HIV indeterminate (n=1)" and "HIV-2 indeterminate (n=1)", suggesting 95.8% HIV-2 differentiation by Geenius. CONCLUSIONS: With Geenius, there were fewer false-positives for HIV-1/-2 negativity and fewer cross-reactions with HIV-2 among HIV-1-positive samples. Additionally, the assay could detect HIV-2 genetic group CRF01_AB. Geenius can be expected to be a useful diagnostic tool that is an alternative to conventional Western blotting.

Clinical usefulness of multiplex PCR-lateral flow for the diagnosis of orthopedic-related infections.

Objectives: Polymerase chain reaction (PCR)-based assays are being increasingly used for the diagnosis of orthopedic-related infections. Unfortunately, classical PCR requires imaging devices that are expensive and complex. We previously developed the PCR-lateral flow (PCR-LF) method, which does not require any additional imaging device. In the present study, the objective was to determine whether PCR-LF tests could be used to effectively diagnose orthopedic-related infections. Methods: In this study, we used PCR-LF to diagnose common causes of orthopedic-related infections and compared the results to those from conventional bacterial cultures of the same samples. Results: Notably, for 228 synovial fluid or pus specimens, the sensitivity and specificity of bacterial cultures were 53.5% and 97.7%, respectively, compared to 61.6% and 89.9% for PCR-LF. Although the difference in sensitivity between bacterial cultures and PCR-LF was not significant, when our analysis was limited to cases with suspected periprosthetic joint infection, the sensitivity of PCR-LF (66.1%) was superior to that of bacterial cultures (42.9%). Conclusion: This study indicates that PCR-LF is a useful method for diagnosing orthopedic-related infections.

Dynamic HIV-1 genetic recombination and genotypic drug resistance among treatment-experienced adults in northern Ghana.

PURPOSE: There have been hardly any reports on the human immunodeficiency virus type 1 (HIV-1) drug-resistance profile from northern Ghana since antiretroviral therapy (ART) was introduced over a decade ago. This study investigated prevailing HIV-1 subtypes and examined the occurrence of drug resistance in ART-experienced patients in Tamale, the capital of the Northern Region of Ghana. METHODOLOGY: A cross-sectional study was carried out on HIV-infected adult patients receiving first-line ART. HIV viral load (VL) and CD4+ T-cell counts were measured. The pol gene sequences were analysed for genotypic resistance by an in-house HIV-1 drug-resistance test; the prevailing HIV-1 subtypes were analysed in detail.Results/Key findings. A total of 33 subjects were studied. Participants comprised 11 males (33.3 %) and 22 (66.7 %) females, with a median age of 34.5 years [interquartile range (IQR) 30.0-40.3]. The median duration on ART was 12 months (IQR 8.0-24). Of the 24 subjects successfully genotyped, 10 (41.7 %) viruses possessed at least one mutation conferring resistance to nucleoside or non-nucleoside reverse-transcriptase inhibitors (NRTIs/NNRTIs). Two-class drug resistance to NRTI and NNRTI was mostly detected (25 %, 6/24). The most frequent mutations were lamivudine-resistance M184V and efavirenz/nevirapine-resistance K103N. HIV-1 subtype CRF02_AG was predominant (79.2 %). Other HIV-1 subtypes detected were G (8.3 %), A3 (4.2 %) and importantly two (8.3 %) unique HIV-1 recombinant forms with CRF02_AG/A3 mosaic. CONCLUSION: HIV-1 shows high genetic diversity and on-going viral genetic recombination in the study region. Nearly 42 % of the patients studied harboured a drug-resistant virus. The study underscores the need for continued surveillance of HIV-1 subtype diversity; and of drug-resistance patterns to guide selection of second-line regimens in northern Ghana.

Virological characteristics of hepatitis B genotype G/A2 recombination virus in Japan.

AIM: We identified four cases of infection with hepatitis B virus genotype G and A2 recombinant (HBV/G/A2) strains, which were initially overlooked by enzyme immunoassay-based genotyping. The patients were all men who have sex with men (MSM) and inhabited several metropolitan areas of Japan, suggesting that the recombinant strains may be circulating among high-risk groups such as MSM. Here, we investigated the genomic structure and virological properties of the HBV/G/A2 strains. METHODS: Complete genome sequences of the isolates were determined and phylogenetically analyzed. Replication efficiency of HBV/G/A2 was investigated by transfecting plasmids containing 1.24-fold viral genome. The in vivo viral kinetics of HBV/G/A2 were investigated using chimeric mice with humanized livers. RESULTS: Phylogenetic analysis revealed that the four strains were almost identical (>99.7% homologous). The preS2/S region of these strains was highly homologous to that of genotype A2 and the remaining region was almost identical to that of genotype G, reflecting inter-genotypic recombination. Interestingly, in all four cases, genotype A was co-infected as a minor population. In vitro analysis revealed that HBV/G/A2 had a low replication rate. Although detectable viremia was not measurable following the inoculation of HBV/G/A2 into chimeric mice, subsequent superinfection of HBV genotype A greatly enhanced HBV/G/A2 replication and viral spread. CONCLUSION: We found that four cases of HBV/G/A2 recombinant among MSM patients in the metropolitan areas of Japan, and HBV/A co-infections are required for its efficient replication. High-risk groups such as MSM should be carefully tested for infection of genotype G-derived variants.

HIV-1 CRF01_AE and Subtype B Transmission Networks Crossover: A New AE/B Recombinant Identified in Japan.

The major circulating HIV-1 strains in Japan have been subtype B (B) followed by CRF01_AE (AE) in newly diagnosed HIV/AIDS cases. These two subtypes have distinct epidemiological characteristics; B predominates in men who have sex with men, while AE is observed mostly in heterosexuals engaging in high-risk sex. However, transmission networks of these two high-risk populations appear to be crossing over and diffusing. Here we report the emergence of previously unidentified HIV-1 AE/B recombinants in Japan. We initially identified 13 cases with discordant subtyping results with AE (gag MA)/B (pol PR-RT)/AE (env C2V3) by molecular phylogenetic analysis of 1,070 cases who visited Nagoya Medical Center from 1997 to 2012. Genetic characterization of full-length sequences demonstrated that they shared an identical recombinant structure, and was designated as CRF69_01B by the Los Alamos HIV National Laboratory. By reviewing gag, pol, and env sequences collected in the Japanese Drug Resistance HIV-1 Surveillance Network, we found five other CRF69_01B probable cases from different areas in Japan, suggesting that the strain is transmitted widely throughout the country. The time of the most recent common ancestor analyses estimated that CRF69_01B emerged between 1991 and 1995, soon after AE was introduced from neighboring countries in the mid-1990s. Understanding the current epidemic strains is important for the diagnosis and treatment of HIV/AIDS, as well as for the development of globally effective HIV vaccines.

Japanese external quality assessment program to standardize HIV-1 drug-resistance testing (JEQS2010 program) using in vitro transcribed RNA as reference material.

To design appropriate antiretroviral therapy regimens and avoid the emergence of human immunodeficiency virus (HIV)-1 variants with reduced susceptibility to antiretroviral drugs, genotypic drug-resistance testing (HIV genotyping) is strongly recommended. To monitor the quality of HIV genotyping in Japan, we performed an external quality assessment (EQA), named the Japanese external quality assessment program, to standardize HIV genotyping (JEQS). To accurately evaluate the quality of HIV genotyping, we employed as reference material (RM) a well-characterized sample, in vitro transcribed RNA (trRNA) that includes the HIV gag-pol sequence, and created a JEQS2010 panel consisting of three single variant and three mixed trRNA samples. All 11 participating laboratories showed high concordance rates (>96%) for the single variant samples. Eight laboratories also showed good rates of detecting minor variants, but three laboratories failed to detect the variants comprising one-half of the sample. These three laboratories used a common primer that had four internal mismatches to the minor trRNA clone. This program showed the usefulness of trRNA as RM, the high quality of HIV genotyping, and extensive interlaboratory variation in the ability to detect minor variants. These results suggest that improving the quality of HIV genotyping in Japan requires regularly implementing the EQA program and improving the HIV genotyping protocol in each laboratory.

HIV-1 drug-resistance surveillance among treatment-experienced and -naïve patients after the implementation of antiretroviral therapy in Ghana.

BACKGROUND: Limited HIV-1 drug-resistance surveillance has been carried out in Ghana since the implementation of antiretroviral therapy (ART). This study sought to provide data on the profile of HIV-1 drug resistance in ART-experienced and newly diagnosed individuals in Ghana. METHODS: Samples were collected from 101 HIV-1-infected patients (32 ART-experienced cases with virological failure and 69 newly diagnosed ART-naïve cases, including 11 children), in Koforidua, Eastern region of Ghana, from February 2009 to January 2010. The pol gene sequences were analyzed by in-house HIV-1 drug-resistance testing. RESULTS: The most prevalent HIV-1 subtype was CRF02_AG (66.3%, 67/101) followed by unique recombinant forms (25.7%, 26/101). Among 31 ART-experienced adults, 22 (71.0%) possessed at least one drug-resistance mutation, and 14 (45.2%) had two-class-resistance to nucleoside and non-nucleoside reverse-transcriptase inhibitors used in their first ART regimen. Importantly, the number of accumulated mutations clearly correlated with the duration of ART. The most prevalent mutation was lamivudine-resistance M184V (n = 12, 38.7%) followed by efavirenz/nevirapine-resistance K103N (n = 9, 29.0%), and zidovudine/stavudine-resistance T215Y/F (n = 6, 19.4%). Within the viral protease, the major nelfinavir-resistance mutation L90M was found in one case. No transmitted HIV-1 drug-resistance mutation was found in 59 ART-naïve adults, but K103N and G190S mutations were observed in one ART-naïve child. CONCLUSIONS: Despite expanding accessibility to ART in Eastern Ghana, the prevalence of transmitted HIV-1 drug resistance presently appears to be low. As ART provision with limited options is scaled up nationwide in Ghana, careful monitoring of transmitted HIV-1 drug resistance is necessary.

Prevalence of transmitted HIV drug resistance in Iran between 2010 and 2011.

OBJECTIVE: Drug-resistant (DR) HIV emerges during combined antiretroviral treatment (cART), creating concern about widespread transmission of DR-HIV as cART is expanded in resource-limited countries. The aim of this study was to determine the predominant HIV-1 subtypes and prevalence of transmitted DR mutations among antiretroviral-naïve patients in Iran. DESIGN: To monitor transmission of DR HIV, a threshold surveillance based on the world health organization (WHO) guidelines was implemented in Iran. METHODS: For this HIVDR threshold surveillance study, blood samples were collected from 50 antiretroviral-naïve HIV-1-infected patients. Antiretroviral-resistant mutations were determined by sequencing HIV-1 protease, reverse transcriptase and integrase regions. The HIV-1 subtype was determined by sequencing the p17 and C2-V5 regions of the gag and env genes, respectively. RESULTS: Phylogenetic analyses of the sequenced regions revealed that 45 (95.7%) of 47 samples that were successfully obtained were CRF35_AD. The remaining two cases were subtype B (2.1%) and CRF01_AE (2.1%). Consistent results were obtained also from Env and Gag sequences. Regarding prevalence of transmitted DR viruses, two cases were found to harbor reverse transcriptase-inhibitor-resistant mutations (4.3%). In addition, although not in the WHO list for surveillance of transmitted mutations, 13 minor protease-inhibitor-resistant mutations listed in the International AIDS Society-USA panel of drug resistance mutations were found. No DR mutations were detected in the integrase region. CONCLUSIONS: Our study clarified that CRF35_AD is the major subtype among HIV-1-infected patients in Iran. According to the WHO categorization method of HIVDR threshold survey, the prevalence of transmitted drug resistant HIV in Iran was estimated as moderate (5-15%).

Molecular epidemiology of HIV type 1 infection in Iran: genomic evidence of CRF35_AD predominance and CRF01_AE infection among individuals associated with injection drug use.

To understand the molecular epidemiology of HIV-1 infection in Iran, we conducted the first study to analyze the genome sequence of Iranian HIV-1 isolates. For this cross-sectional study, we enrolled 10 HIV-1-infected individuals associated with injection drug use from Tehran, Shiraz, and Kermanshah. Near full-length genome sequences obtained from their plasma samples were used for phylogenetic tree and similarity plotting analyses. Among 10 isolates, nine were clearly identified as CRF35_AD and the remaining one as CRF01_AE. Interestingly, five of our Iranian CRF35_AD isolates made two clusters with 10 Afghan CRF35_AD isolates in a phylogenetic tree, indicating epidemiological connections among injection drug users in Iran and Afghanistan. In contrast, our CRF01_AE isolate had no genetic relationship with any other CRF01_AE isolates worldwide, even from Afghanistan. This study provides the first genomic evidence of HIV-1 CRF35_AD predominance and CRF01_AE infection among individuals associated with injection drug use in Iran.

The carboxyl-terminus of human immunodeficiency virus type 2 circulating recombinant form 01_AB capsid protein affects sensitivity to human TRIM5α.

Human immunodeficiency virus (HIV) type 2 shows limited geographical distribution compared with HIV type 1. Although 8 genetic groups of HIV type 2 (HIV-2) have been described, recombinant viruses between these groups are rarely observed. Recently, three HIV-2 patients in Japan were described with rapidly progressive, acquired immunodeficiency. These patients were infected with an A/B inter-group recombinant designated CRF01_AB. Here, we characterize the capsid protein (CA) encoded by the viruses from these patients. HIV-2 CRF01_AB CA showed unique amino acid sequence almost equally distinct from group A and group B viruses. Notably, HIV-2 CRF01_AB CA showed potent resistance to human TRIM5α. In addition to the previously identified amino acid position 119 in the N-terminal domain of CA, we found that HIV-2 CRF01_AB-specific amino acid substitutions in the C-terminal domain also were necessary for resistance to human TRIM5α. These results indicate that retroviruses can evade TRIM5α by substitution at residues within the C-terminal domain of CA.

Cellular HIV-1 DNA levels in patients receiving antiretroviral therapy strongly correlate with therapy initiation timing but not with therapy duration.

BACKGROUND: Viral reservoir size refers to cellular human immunodeficiency virus-1 (HIV-1) DNA levels in CD4(+) T lymphocytes of peripheral blood obtained from patients with plasma HIV-1-RNA levels (viral load, VL) maintained below the detection limit by antiretroviral therapy (ART). We measured HIV-1 DNA levels in CD4(+) lymphocytes in such patients to investigate their clinical significance. METHODS: CD4(+) T lymphocytes were isolated from the peripheral blood of 61 patients with a VL maintained at less than 50 copies/ml for at least 4 months by ART and total DNA was purified. HIV-1 DNA was quantified by nested PCR to calculate the copy number per 1 million CD4(+) lymphocytes (relative amount) and the copy number in 1 ml of blood (absolute amount). For statistical analysis, the Spearman rank or Wilcoxon signed-rank test was used, with a significance level of 5%. RESULTS: CD4 cell counts at the time of sampling negatively correlated with the relative amount of HIV-1 DNA (median = 33 copies/million CD4(+) lymphocytes; interquartile range [IQR] = 7-123 copies/million CD4(+) lymphocytes), but were not correlated with the absolute amounts (median = 17 copies/ml; IQR = 5-67 copies/ml). Both absolute and relative amounts of HIV-1 DNA were significantly lower in six patients in whom ART was initiated before positive seroconversion than in 55 patients in whom ART was initiated in the chronic phase, as shown by Western blotting. CD4 cell counts before ART introduction were also negatively correlated with both the relative and absolute amounts of HIV-1 DNA. Only the relative amounts of HIV-1 DNA negatively correlated with the duration of VL maintenance below the detection limit, while the absolute amounts were not significantly correlated with this period. CONCLUSIONS: The amounts of cellular HIV-1 DNA in patients with VLs maintained below the detection limit by the introduction of ART correlated with the timing of ART initiation but not with the duration of ART. In addition, CD4(+) T lymphocytes, which were newly generated by ART, diluted latently infected cells, indicating that measurements of the relative amounts of cellular HIV-1 DNA might be underestimated.

Clinical significance of HIV reverse-transcriptase inhibitor-resistance mutations.

In this article, we summarize recent knowledge on drug-resistance mutations within HIV reverse transcriptase (RT). Several large-scale HIV-1 genotypic analyses have revealed that the most prevalent nucleos(t)ide analog RT inhibitor (NRTI)-resistance mutation is M184V/I followed by a series of thymidine analog-associated mutations: M41L, D67N, K70R, L210W, T215Y/F and K219Q/E. Among non-nucleoside RT inhibitor (NNRTI)-resistance mutations, K103N was frequently observed, followed by Y181C and G190A. Interestingly, V106M was identified in HIV-1 subtype C as a subtype-specific multi-NNRTI-resistance mutation. Regarding mutations in the HIV-1 RT C-terminal region, including the connection subdomain and RNase H domain, their clinical impacts are still controversial, although their effects on NRTI and NNRTI resistance have been confirmed in vitro. In HIV-2 infections, the high prevalence of the Q151M mutation associated with multi-NRTI resistance has been frequently observed.

Outbreak of infections by hepatitis B virus genotype A and transmission of genetic drug resistance in patients coinfected with HIV-1 in Japan.

The major routes of hepatitis B virus (HBV) infection in Japan has been mother-to-child transmission (MTCT) and blood transfusion. However, HBV cases transmitted through sexual contact are increasing, especially among HIV-1-seropositive patients. To understand the molecular epidemiology of HBV in HBV/HIV-1 coinfection, we analyzed HBV genotypes and HIV-1 subtypes in HBV/HIV-1-coinfected patients at Nagoya Medical Center from 2003 to 2007. Among 394 HIV-1-infected Japanese men having sex with men (MSM) who were newly diagnosed during the study period, 31 (7.9%) tested positive for the hepatitis B virus surface antigen. HBV sequence analyses were successful in 26 cases, with 21 (80.7%) and 5 (19.3%) cases determined as genotypes A and C, respectively. Our finding that HBV genotype A was dominant in HIV-1-seropositive patients alerts clinicians to an alternative outbreak of HBV genotype A in the HIV-1-infected MSM population and a shift in HBV genotype from C to A in Japan. The narrow genetic diversity in genotype A cases suggests that genotype A has been recently introduced into the MSM population and that sexual contacts among MSM were more active than speculated from HIV-1 tree analyses. In addition, we found a lamivudine resistance mutation in one naïve case, suggesting a risk of drug-resistant HBV transmission. As genotype A infection has a higher risk than infection with other genotypes for individuals to become HBV carriers, prevention programs are urgently needed for the target population.

Trends in transmitted drug-resistant HIV-1 and demographic characteristics of newly diagnosed patients: nationwide surveillance from 2003 to 2008 in Japan.

The emergence and transmission of drug-resistant human immunodeficiency virus-1 (HIV-1) compromises antiretroviral treatment for HIV-1. Thus, testing for drug resistance is recommended at diagnosis and before initiating highly active antiretroviral treatment. We conducted an epidemiological study enrolling newly diagnosed patients between 2003 and 2008 in our nationwide surveillance network. In the 6-year study period, the prevalence of drug-resistant HIV-1 among 2573 patients, consisting mainly of Japanese men in their late-30s and infected through male-to-male sexual contacts, followed an increasing trend from 5.9% (16/273) in 2003 to 8.3% (50/605) in 2008. Nucleoside reverse transcriptase inhibitor-associated mutations predominated in each year, with T215 revertants being the most abundant. The predictive factor for drug-resistant HIV-1 transmission was subtype B (OR=2.36; p=0.004), and those for recent HIV-1 infection were male gender (OR=3.79; p=0.009), MSM behavior (OR=1.67; p=0.01), Japanese nationality (OR=2.31; p=0.008), and subtype B (OR=5.64; p<0.05). Continued activities are needed to raise awareness of the risks of HIV-1 infection and complications of drug-resistant strains. Continued surveillance is also needed to understand trends in the HIV-1 epidemic.

HIV-2 CRF01_AB: first circulating recombinant form of HIV-2.

BACKGROUND: Five HIV-2-seropositive cases were recently identified in Japan, outside the HIV-2 endemic area of West Africa. To clarify the molecular epidemiology of HIV-2 in Japan, we analyzed sequences of these cases in detail. METHODS: HIV-2 genetic groups were determined by gag and env sequences. For suspected recombinant isolates, the genetic structure was determined by full-length genomic analyses. To understand the history and evolution of HIV-2 recombinant isolates, we estimated the time of most recent common ancestor by Bayesian Markov chain Monte Carlo method. RESULTS: Three isolates were determined as recombinants of groups A and B, and their mosaic genome structures were identical with that of 7312A, a recombinant isolate reported in 1990 from Côte d'Ivoire. Our 3 isolates and 7312A fulfilled the criteria for determining a circulating recombinant form (CRF). These isolates were verified by the Los Alamos HIV sequence database as the first CRF of HIV-2, HIV-2 CRF01_AB. The mean time of most recent common ancestor of CRF01_AB was estimated as between 1964 and 1973, several decades after the estimated emergence of HIV-2. CONCLUSIONS: We recently identified HIV-2 CRF01_AB cases in Japan. This ectopic observation of the virus outside its original endemic area suggests an ongoing global spread of HIV-2 CRF01_AB.

[Current topics on drug-resistant HIV in Japan].

The prevalence of drug-resistant HIV among newly diagnosed HIV/AIDS cases in Japan increased from 4.9% (14/288) to 9.1% (43/473) in recent five years. This strengthens the importance of continuous surveillance to understand the epidemiological nature of transmitted drug-resistant HIV in our country. Regarding multi-drug-resistance among on-treated cases, the prevalence was estimated to be less than 1.9% (51/2,715). Both an increased mortality rate (26%) and a high rate of uncontrolled viremia (26%) were observed in three-class-resistant cases. However, 26% of three-class-resistant cases were successful in their salvage therapies containing new antiretrovirals, darunavir, raltegravir, maraviroc, and etravirine.

An 11-Year Surveillance of HIV Type 1 Subtypes in Nagoya, Japan.

Abstract To monitor active HIV-1 transmission in Nagoya, Japan, we have been determining the subtypes of HIV-1 infecting therapy-naive individuals who have newly visited the Nagoya Medical Center since 1997. The subtypes were determined by phylogenetic analyses using the base sequences in three regions of the HIV-1 genes including gag p17, pol protease (PR) and reverse transcriptase (RT), and env C2V3. Almost all HIV-1 subtypes from 1997 to 2007 and 93% of all HIV-1 isolates in 2007 were subtype B. HIV-1 subtypes A, C, D, and F have been detected sporadically since 1997, almost all in Africans and South Americans. The first detected circulating recombinant form (CRF ) was CRF01_AE (11-year average annual detection rate, 7.7%). Only two cases of CRF02_AG were detected in 2006. A unique recombinant form (URF ) was first detected in 1998 and the total number of URFs reached 25 by year 2007 (average annual detection rate, 4.7%). Eleven of these 25 were detected from 2000 to 2005 and had subtypes AE/B/AE as determined by base sequencing of the gag p17, pol PR and RT, and env C2V3 genes (average annual detection rate, 3.7%). Unique subtype B has been detected in six cases since 2006. All 17 of these patients were Japanese. Other recombinant HIV-1s have been detected intermittently in eight cases since 1998. During the 11-year surveillance, most HIV-1s in Nagoya, Japan were of subtype B. We expect that subtype B HIV-1 will continue to predominate for the next several years. Active recombination between subtype B and CRF01_AE HIV-1 and its transmission were also shown.

Analysis of near full-length genomic sequences of drug-resistant HIV-1 spreading among therapy-naïve individuals in Nagoya, Japan: amino acid mutations associated with viral replication activity.

We analyzed a total of 12 near full-length genomes of drug-resistant HIV-1 spreading among therapy-naïve individuals in Nagoya, Japan. Genomes comprised seven protease inhibitor (PI)-resistant viruses possessing an M46I (n = 6) or L90M mutation (n = 1) and five non-nucleoside reverse transcriptase inhibitor-resistant viruses possessing a K103N mutation. All 12 viruses conserved both an H87Q mutation in the cyclophilin A-binding site of Gag p24 (capsid) and a T23N mutation in the cysteine-rich domain of Tat protein. PI-resistant viruses commonly possessed two cleavage site mutations in the p6(Pol)/protease of Pol polyprotein (F48L in p6(Pol)) and the anchor/core domains of Nef protein (L57V). These amino acid mutations represent candidates for enhancing replication activity of drug-resistant viruses and supporting expansion of such viruses in therapy-naïve individuals.

Trend of drug-resistant HIV type 1 emergence among therapy-naive patients in Nagoya, Japan: an 8-year surveillance from 1999 to 2006.

We studied the emergence of drug-resistant human immunodeficiency virus type 1 (HIV-1) with major amino acid mutations in 402 therapy-naive patients at Nagoya Medical Center, Japan, between 1999 and 2006. The mean prevalence of drug-resistant HIV-1 was 6.7% (range, 2.3-10.0%; n = 27). HIV-1 variants with protease inhibitor (PI)-resistant mutations alone were most frequently found (3.5%, n = 14), followed by those with nonnucleoside reverse transcriptase inhibitor (NNRTI)-resistant mutations alone (1.7%, n = 7). Variants with nucleoside reverse transcriptase inhibitor (NRTI)-resistant mutations alone were sporadically found (1.0%, n = 4). A variant possessing both NRTI- and PI-resistant mutations was detected in one patient (0.2%) and a variant possessing both NNRTI- and PI-resistant mutations was identified in another patient (0.2%). In addition, another 17 variants (4.2%, n = 17) with only 215-revertant mutations (T215C/D/G/L/S) that can easily reconvert to the nucleoside analogue-associated mutation of T215Y/F were found. The 402 viruses were phylogenetically analyzed, revealing three independent clusters comprising PI-resistant variants with the M46I or L90M mutation, NNRTI-resistant variants with the K103N mutation, and 215-revertant variants. The PI-resistant and 215-revertant strains have been spreading since 2000, and the NNRTI-resistant strain has started spreading since 2003. The nature of the epidemic and information for successfully blocking the spread of drug-resistant HIV-1 were clarified in this study.

No observable correlation between central nervous system side effects and EFV plasma concentrations in Japanese HIV type 1-infected patients treated with EFV containing HAART.

The present study assessed the relationship between central nervous system (CNS) side effects and plasma concentrations of efavirenz (EFV) in Japanese HIV-1-infected patients. Subjects consisted of 69 HIV-1-infected patients (57 therapy-naive and 12 therapy-experienced patients) being treated using EFV in combination with other antiretroviral agents at the outpatient HIV clinic. Successful virological treatment was achieved in 61 patients. Eight patients discontinued EFV containing therapy because CNS symptoms did not resolve (four patients), EFV-specific mutations were detected (two patients), or skin rash was observed (two patients). Mean EFV plasma concentration for 61 effectively treated patients, measured at 15 h postdosing, was 2.42 microg/ml (range: 0.78-6.82 microg/ml). This EFV concentration range contributed to suppressed viral load in these Japanese patients. Adverse CNS effects were observed in 19 patients soon after therapy onset. These effects disappeared within 1 month except for four patients who suffered severe CNS side effects. Mean EFV plasma concentrations were not significantly different between subjects with (2.45 +/- 1.08 microg/ml) and without (2.42 +/- 1.40 microg/ml) CNS side effects. We concluded no correlation existed between the plasma EFV concentration and the emergence of CNS side effects in Japanese HIV-1-infected patients. Further investigations, enforced with the drug concentration measurement at earlier time points and more appropriate assessment of CNS symptoms, are required.