Adverse bone health and abnormal bone turnover among perinatally HIV-infected Asian adolescents with virological suppression.

OBJECTIVES: This study aimed to determine the prevalence of low bone mass and assess its relationship with abnormal bone turnover among HIV-infected Asian adolescents. METHODS: A multicentre, cross-sectional study was conducted at four paediatric HIV centres in Thailand and Indonesia. Perinatally HIV-infected adolescents aged 10-18 years receiving antiretroviral therapy (ART) with virological suppression (HIV RNA < 400 copies/mL) were enrolled. Study assessments included lumbar spine (L2-L4) dual-energy X-ray absorptiometry and measurement of bone turnover markers. Bone mineral density (BMD) and bone mineral apparent density (BMAD) Z-scores were calculated based on Thai normative age- and sex-matched references. Low bone mass was defined as BMD or BMAD Z-scores ≤ -2. RESULTS: Of 396 participants, 57% were female. The median age was 15.0 [interquartile range (IQR) 13.3-16.9] years, and 73% were in Tanner stage 3-5. At enrolment, the median CD4 T-cell count was 734 (IQR 581-907) cells/µL, and 37% were on protease inhibitor (PI)-based regimens. The overall prevalence of lumbar spine BMD and BMAD Z-scores ≤ -2 were 16.4% and 8.3%, respectively. Z-scores were lower with older age, female sex, body mass index (BMI) <5th percentile, boosted PI exposure and CD4 T-cell percentage < 15% before ART initiation. Increased bone turnover markers were inversely associated with BMD and BMAD Z-scores. CONCLUSIONS: Low bone mass was linked to older age, female sex, low BMI, boosted PI exposure, and poor immunological status before ART commencement in our cohort of perinatally HIV-infected Asian adolescents. Dysregulation of bone turnover was associated with bone demineralization. Screening for low bone mass should be implemented to identify individuals who might benefit from interventions to preserve bone health.

Correlation of selenium and zinc levels to antiretroviral treatment outcomes in Thai HIV-infected children without severe HIV symptoms.

BACKGROUND/OBJECTIVES: Deficiencies in antioxidants contribute to immune dysregulation and viral replication. To evaluate the correlation of selenium (Se) and zinc (Zn) levels on the treatment outcomes in HIV-infected children. SUBJECTS/METHODS: HIV-infected Thai children 1-12 years old, CD4 15-24%, without severe HIV symptoms were included. Se and Zn levels were measured by graphite furnace atomic absorption spectrometry at baseline and 48 weeks. Deficiency cutoffs were Se <0.1 µmol/l and Zn <9.9 µmol/l. Serum ferritin and C-reactive protein (CRP) were measured every 24 weeks. No micronutrient supplement was prescribed. RESULTS: In all, 141 children (38.3% male) with a median (interquartile range (IQR)) age of 7.3 (4.2-9.0) years were enrolled. Median baseline CD4% was 20%, HIV-RNA was 4.6 log(10)copies/ml. At baseline, median (IQR) Se and Zn levels were 0.9 (0.7-1.0) µmol/l and 5.9 (4.8-6.9) µmol/l, respectively. None had Se deficiency while all had Zn deficiency. Over 48 weeks, 97 initiated antiretroviral therapy (ART) and 81% achieved HIV-RNA <50 copies/ml with 11% median CD4 gain. The mean change of Se was 0.06 µmol/l (P=0.003) and Zn was 0.42 µmol/l (P=0.003), respectively. By multivariate analysis in children who received ART, predictors for greater increase of CD4% from baseline were lower baseline CD4% (P<0.01) and higher baseline Zn level (P=0.02). The predictors for greater decrease of HIV-RNA from baseline were higher baseline HIV-RNA and higher ferritin (both P<0.01). No association of CRP with the changes from baseline of CD4% or HIV-RNA was found. CONCLUSION: In HIV-infected Thai children without severe immune deficiency who commenced ART, no correlation between Se and ART treatment outcomes was found. Higher pre-ART Zn levels were associated with significant increases in CD4% at 48 weeks.

HIV-1 drug resistance mutations in children after failure of first-line nonnucleoside reverse transcriptase inhibitor-based antiretroviral therapy.

OBJECTIVES: The aim of the study was to assess the prevalence, predictors and patterns of genotypic resistance mutations in children after failure of World Health Organization-recommended initial nonnucleoside reverse transcriptase inhibitor (NNRTI)-based treatment regimens. METHODS: We carried out a multicentre retrospective study of genotyping tests performed for all HIV-infected children at eight paediatric centres in Thailand who experienced failure of NNRTI therapy at a time when virological monitoring was not routinely available. RESULTS: One hundred and twenty children were included in the study. Their median age (interquartile range) was 9.1 (6.8-11.0) years, the median duration of their NNRTI regimens was 23.7 (15.7-32.6) months, their median CD4 percentage was 12% (4-20%), and their median plasma HIV RNA at the time of genotype testing was 4.8 (4.3-5.2) log(10) HIV-1 RNA copies/mL. The nucleoside reverse transcriptase inhibitor (NRTI) resistance mutations found were as follows: 85% of the children had M184V/I, 23% had at least four thymidine analogue mutations, 12% had the Q151M complex, 5% had K65R, and 1% had the 69 insertion. Ninety-eight per cent of the children had at least one NNRTI resistance mutation, and 48% had etravirine mutation-weighted scores ≥4. CD4 percentage <15% prior to switching regimens [odds ratio (OR) 5.49; 95% confidence interval (CI) 2.02-14.93] and plasma HIV RNA>5 log(10) copies/mL (OR 2.46; 95% CI 1.04-5.82) were independent predictors of at least four thymidine analogue mutations, the Q151M complex or the 69 insertion. CONCLUSIONS: In settings without routine viral load monitoring, second-line antiretroviral therapy regimens should be designed assuming that clinical or immunological failure is associated with high rates of multi-NRTI resistance and NNRTI resistance, including resistance to etravirine.

Ferritin levels during structured treatment interruption of highly active antiretroviral therapy.

OBJECTIVE: The aim of the study was to investigate the influence of highly active antiretroviral therapy (HAART) on iron status and, conversely, the influence of iron status on the response to HAART. METHODS: Ferritin levels were retrospectively determined in stored plasma from 138 HAART-naïve, moderately immunosuppressed HIV-infected Thai patients participating in a structured treatment interruption trial. Ferritin levels were determined at three predefined time-points: (1) HAART initiation; (2) HAART discontinuation; and (3) HAART resumption. RESULTS: At baseline, 31% and 16% of the HIV-infected patients included in the study had high (>200 ng/mL) and low (<30 ng/mL) ferritin levels, respectively. Ninety-five per cent of patients with low ferritin levels were female. Ferritin decreased significantly during the interruption phase of HAART (-8.8 ng/mL; P=0.0005) but remained elevated in 62% of the patients with high baseline levels. A low baseline ferritin level was associated with a shorter time (P=0.041) to reach the CD4 cell target for HAART interruption (350 cells/microL), compared with a normal or high baseline ferritin level. Moreover, in a multivariate model, the relative risk (RR) of arriving at this CD4 cell target was significantly higher [RR 1.81; 95% confidence interval (CI) 1.05-3.14] in patients with low baseline ferritin. It is unlikely that inflammation affected ferritin in our patients, as mean levels of C-reactive protein were not elevated in patients with either high or low ferritin levels. CONCLUSIONS: Both high and low ferritin levels were highly prevalent in moderately immunosuppressed HIV-positive Thai patients. Structured treatment interruption of HAART resulted in a significant decrease in overall ferritin levels. Furthermore, subjects with low baseline ferritin levels had a faster and greater CD4 response to HAART, suggesting a potential beneficial effect of iron deficiency on immunological recovery after initiation of HAART.

Advantage of a two-dose versus one-dose varicella vaccine in healthy non-immune teenagers and young adults.

This study was undertaken to compare the immunogenicity and reactogenicity of two vaccines based on the attenuated Oka-strain of Varicella zoster virus (VZV), in adolescents and young adults. One hundred and eighty-six subjects, aged 13 to 29 years, were randomized to one of two groups to receive a one- or a two-dose VZV vaccine. Pre- and post-vaccination blood samples were assayed for VZV-specific IgG. Solicited local and general symptoms, as well as unsolicited symptoms, were recorded post-vaccination. Seroconversion rates were 94.9% in the one-dose, and 100% in the two-dose, regimen. The two-dose vaccine elicited significantly higher geometric mean antibody titer, 392.5 vs 86.8 pfu. Transient local injection site pain was the most frequently-reported symptom per dose in both groups (one dose: 48.9%; two-dose: 32.8%). The two-dose vaccine regimen afforded the advantage of higher antibody titers and potential increased protection from disease, without significantly increased reactogenicity.

Prevention of HIV transmission from mother-to-child in Srinagarind Hospital.

From January 1996 to December 1999, HIV infected pregnant women and their newborns were studied. Informed consent was obtained and HIV-tests were performed after counselling. ZDV for perinatal prophylaxis starting on week 14 to week 36 of gestation and continued throughout pregnancy was given following an ACTG 076 regimen except that during labour, intravenous ZDV was replaced by oral ZDV 300 mgs, given every 3-hours as a loading dose and ZDV syrup 2 mgs/kg every 6 hours for 7 days orally for the newborns. Newborn HIV-Ab and PCR were done at 6 weeks and 6 months after birth. Eighty-four HIV infected pregnant women were enrolled in the study, eighty-three of whom were delivered. The overall transmission rate was 5.2 per cent, with 3/58 children confirmed infected with HIV by at least two positive PCR test results.

Survival of children with AIDS: experience in a university hospital in northeast Thailand.

The survival experience of pediatric AIDS patients from three points: birth, age at first symptom and age at AIDS diagnosis (by the WHO definition) was studied. We had 90 subjects, 46 males and 44 females. They were under 15 years of age and were diagnosed as having perinatally-acquired pediatric AIDS. The children came to Srinagarind Hospital between January, 1989 and December, 1997. They were followed-up until April 30, 1998. Patients who did not come to the hospital were traced by confidential mail. The two most common first symptoms were chronic diarrhea (36.7%) and persistent lower respiratory tract infection (34.4%). The median age at the first symptom was four months (95% CI = 3 to 5 months) and the median age at diagnosis was 13 months (95% CI = 11 to 15 months). Thirty-nine cases received antiretroviral treatment, either AZT, ddI or both. Forty-five cases died, 18 cases lived to the end of the study, 27 could not be followed-up. A survival curve was calculated according to the Kaplan and Meier method using SPSS version 6.0. The 1- and 2-year survival rates from the time of the first symptom were 75.3 per cent (95% CI = 65.8% to 84.7%) and 60.3 per cent (95% CI = 49.0% to 71.6%). The corresponding survival rates from AIDS diagnosis were 59.7 per cent (95% CI = 48.4% to 71.1%) and 42.8% (95% CI = 30.3% to 55.3%), respectively.

Epidemiology of invasive meningococcal disease in 13 government hospitals in Thailand, 1994-1999.

This study was conducted to elucidate the magnitude of problem and the clinical course of invasive meningococcal infection from 13 government hospitals in Thailand between 1994 and 1999. Thirty-six strains of Neisseria meningitidis were isolated from 16 blood and 24 cerebrospinal fluid specimens; 4 patients had positive culture in both blood and CSF. Of the 16 strains, 9 (56.3%) were serogroup B. Seventy-one and eighty-four percent of the isolates were susceptible to penicillin and cefotaxime/ceftriaxone respectively. Five out of six penicillin-nonsusceptible strains were found to be relatively resistant to penicillin with the MIC of 0.125 microg/ml. Of 33 patients whose medical records were available, 21 were males and 12 were females, with a mean age of 11.2 years. Fifteen patients (45.5%) presented with meningococcemia and 18 patients (54.5%) presented with meningococcal meningitis. Hypotension and purpura were found in 24.2% and 33.3% of patients respectively. The overall mortality rate was 9.1%. In conclusion, meningococcal disease is not common in Thailand, meningococcemia is a life-threatening condition whereas meningococcal meningitis is much less severe. The prevalence of meningococci relatively resistant to penicillin seems to be increasing.

Comparative fitness of multi-dideoxynucleoside-resistant human immunodeficiency virus type 1 (HIV-1) in an In vitro competitive HIV-1 replication assay.

We examined whether human immunodeficiency virus type 1 (HIV-1) fitness was altered upon the acquisition of a set or subset of five mutations (A62V, V75I, F77L, F116Y, and Q151M) in the pol gene, which confers resistance to multiple dideoxynucleosides (MDR), as well as the zidovudine resistance-associated mutation T215Y, using a competitive HIV-1 replication assay in a setting of an HXB2D genetic background. Target H9 cells were exposed to a 50:50 mixture of paired infectious molecular clones, and HIV-1 in the culture supernatant was transmitted to new cultures every 7 to 10 days. The polymerase-encoding region of the virus was sequenced at various time points, and the relative proportion of the two viral populations was determined. In the absence of drugs, the comparative order for replicative fitness was HIV-162/75/77/116/151 > HIV-177/116/151 > HIV-1151 > wild-type HIV-1 (HIV-1wt) > HIV-175/77/116/151 > HIV-1151/215 > HIV-1215. In the presence of zidovudine or didanosine, the order was HIV-162/75/77/116/151 > HIV-177/116/151 > HIV-175/77/116/151 > HIV-1151 > HIV-1215. HIV-1215S(TCC), a putative intermediate infectious clone for HIV-1215, replicated comparably to HIV-1wt, while two putative intermediates for HIV-1151 [HIV-1151L(CTG) and HIV-1151K(AAG)] replicated much less efficiently than HIV-1wt and HIV-1151, suggesting that for HIV-1151 to develop, two base substitutions are likely to occur concurrently or within a short interval. These data may illustrate the molecular basis by which HIV-1151 emerges much less frequently than HIV-1215. The present data also demonstrate that several MDR HIV-1 variants are more fit than HIV-1wt in the absence of drugs and that resistance-associated mutations and drug pressure are critical variates for HIV-1 fitness.

In vitro anti-human immunodeficiency virus activities of Z- and E-methylenecyclopropane nucleoside analogues and their phosphoro-L-alaninate diesters.

Nucleoside analogues with a Z- or an E-methylenecyclopropane moiety were synthesized and examined for activity against human immunodeficiency virus type 1 (HIV-1) in vitro. The addition of a methyl phenyl phosphoro-L-alaninate moiety to modestly active analogues resulted in potentiation of their anti-HIV-1 activity. Two such compounds, designated QYL-685 (with 2,6-diaminopurine) and QYL-609 (with adenine), were most potent against HIV-1 in vitro, with 50% inhibitory concentrations of 0.034 and 0.0026 microM, respectively, in MT-2 cell-based assays. Both compounds were active against zidovudine-resistant, didanosine-resistant, and multi-dideoxynucleoside-resistant infectious clones in vitro. Further development of these analogues as potential therapies for HIV-1 infection is warranted.

HIV-1 acquires resistance to two classes of antiviral drugs through homologous recombination.

Genetic recombination contributes to the genomic heterogeneity of human immunodeficiency virus type 1 (HIV-1). In the present study, we demonstrate that HIV-1 readily develops resistance to two classes of anti-HIV-1 drugs through in vitro genetic recombination involving large segments of the viral genome. Co-transfection of COS-7 cells with an HIV-1 plasmid (pSUM13) carrying five mutations in the reverse transcriptase (RT)-encoding region (A62V, V75I, F77L, F116Y, Q151M), conferring resistance to multiple dideoxynucleoside analogs (ddNs), and another HIV-1 plasmid (pSUM431) carrying five mutations in the protease-encoding region (V321, L33F, K451, 184V, L89M), conferring resistance to protease inhibitors such as KNI-272, readily produced HIV-1 carrying both sets of mutations when propagated in MT-2 cells in the presence of azidothymidine (AZT) and KNI-272. The resultant HIV-1 variant was highly resistant to both ddNs and KNI-272. Co-infection of MT-2 cells with HIV-1SUM13 carrying the RT mutations and HIV-1SUM431 carrying the mutations in the protease also generated HIV-1 with both sets of mutations when cultured with AZT and KNI-272. We also report here that the problematic artifactual recombination occurring during genetic analyses of heterogeneous nucleic acid sequences using polymerase chain reaction can be successfully obviated.

Seroepidemiology of hepatitis A virus antibody in primary school children in Khon Kaen Province, northeastern Thailand.

Hepatitis A is a disease commonly found in Thai children. Since 1984, there have been very few reports on the age specific prevalence of hepatitis A virus infection in the northeastern part of Thailand, which has the largest population and is the poorest area of the country. We studied the seroprevalence of hepatitis A virus (HAV) antibody in 3 primary school children in different areas of Khon Kaen Province, northeastern Thailand. Anti-HAV level was assayed by ELISA. Four hundred and forty-one children age 6-12 years were selected from one primary school in the urban area and two from rural areas. The highest prevalence was 22.6% at age 12 years and 0 at age 6 years. The seroprevalence was highest, 45%, in rural school children of the lowest socioeconomic status as compared to 10.8% and 2.6% in other urban school children. The overall prevalence was 12.7% and the age specific prevalence with 95% CI are presented. These data indicated a much lower seroepidemiological prevalence than previously reported and might be related to the level of socioeconomic and standard of public sanitation and living conditions.