Takeshi Nishijima

Impact of small body weight on tenofovir-associated renal dysfunction in HIV-infected patients: a retrospective cohort study of Japanese patients.

Background Treatment with tenofovir is sometimes associated with renal dysfunction. Limited information is available on this side effect in patients with small body weight, although the use of tenofovir will spread rapidly in Asia and Africa, where patients are likely to be of smaller body weight. Methods In a single-center cohort, Japanese patients with HIV infection who started tenofovir-containing antiretroviral therapy were retrospectively analyzed. The incidence of tenofovir-associated renal dysfunction, defined as more than 25% decrement of estimated glomerular filtration rate (eGFR) from the baseline, was determined. The effects of small body weight and body mass index (BMI) on tenofovir-associated renal dysfunction, respectively, were estimated in univariate and multivariate Cox hazards models as the primary exposure. Other possible risk factors were evaluated by univariate analysis and those found significant were entered into the multivariate analysis. Results The median weight of 495 patients was 63 kg. Tenofovir-related renal dysfunction occurred in 97 (19.6%) patients (incidence: 10.5 per 100 person-years). Univariate analysis showed that the incidence of tenofovir-related renal dysfunction was significantly associated with smaller body weight and BMI, respectively (per 5 kg decrement, HRu200a=u200a1.23; 95% CI, 1.10–1.37; p<0.001)(per 1 kg/m2 decrement, HRu200a=u200a1.14; 95% CI, 1.05–1.23; pu200a=u200a0.001). Old age, high baseline eGFR, low serum creatinine, low CD4 count, high HIV viral load, concurrent nephrotoxic drugs, hepatitis C infection, and current smoking were also associated with tenofovir-related renal dysfunction. Multivariate analysis identified small body weight as a significant risk (adjusted HRu200a=u200a1.13; 95% CI, 1.01–1.27; pu200a=u200a0.039), while small BMI had marginal significance (adjusted HRu200a=u200a1.07; 95% CI 1.00–1.16; pu200a=u200a0.058). Conclusion The incidence of tenofovir-associated renal dysfunction in Japanese patients was high. Small body weight was identified as an independent risk factor for tenofovir-associated renal dysfunction. Close monitoring of renal function is advocated for patients with small body weight treated with tenofovir.

High Incidence of Renal Stones Among HIV-Infected Patients on Ritonavir-Boosted Atazanavir Than in Those Receiving Other Protease Inhibitor–Containing Antiretroviral Therapy

BACKGROUNDnLittle information is available on the incidence of renal stones with ritonavir-boosted atazanavir (ATV/r) use.nnnMETHODSnIn a single-center study, the incidence of renal stones was compared between human immunodeficiency virus (HIV)-infected patients who commenced ritonavir-boosted atazanavir (ATV/r)-containing antiretroviral (ARV) therapy (the ATV/r group) and those who were receiving other protease inhibitors (the other PIs group). The effects of ATV/r were estimated by univariate and multivariate Cox proportional hazards regression models. Other possible risk factors were evaluated by univariate analysis, and those found to be significant were entered into multivariate analysis.nnnRESULTSnRenal stones were diagnosed in 31 patients (23.7 cases per 1000 person-years) in the ATV/r group (n = 465) and 4 in patients (2.2 cases per 1000 person-years) in the other PIs group (n = 775). ATV/r use was significantly associated with renal stones, by univariate and multivariate analyses (adjusted hazard ratio, 10.44; 95% confidence interval [CI], 3.685-29.59; P < .001). ATV/r remained a significant risk factor for renal stones in all subgroups stratified by the median values of baseline variables. In the 31 patients receiving ATV/r who developed renal stones, the median time from commencement of ATV/r to diagnosis was 24.5 months (interquartile range, 14.7-34.6 months). Of the 18 patients who continued ATV/r despite the diagnosis of renal stones, 6 (33.3%) experienced recurrence. No patient who discontinued ATV/r experienced recurrence during the observation period (250.6 person-months).nnnCONCLUSIONSnThe incidence of renal stones was substantially higher among patients in the ATV/r group, compared with patients in the other PIs group. Continuation of ATV/r after diagnosis of renal stones was associated with a high rate of recurrence. Switching ATV/r to other ARVs is warranted in patients who develop renal stones.

Single Nucleotide Polymorphisms in ABCC2 Associate With Tenofovir-Induced Kidney Tubular Dysfunction in Japanese Patients With HIV-1 Infection: A Pharmacogenetic Study

BACKGROUNDnTenofovir is a widely used antiretroviral drug although it can cause kidney tubular dysfunction (KTD). The aim of this study was to determine the association between polymorphisms in genes encoding drug transporters and KTD in Japanese patients treated with tenofovir.nnnMETHODSnThe association between tenofovir-induced KTD and 14 single nucleotide polymorphisms (SNPs) in the ABCC2, ABCC4, ABCC10, SCL22A6, and ABCB1 genes was investigated in 190 Japanese patients. KTD was diagnosed by the presence of at least 3 abnormalities in the following parameters: fractional tubular resorption of phosphate, fractional excretion of uric acid, urinary β2-microglobulin, urinary α1-microglobulin, and urinary N-acetyl-β-D-glucosaminidase. Genotyping was performed by allelic discrimination using TaqMan 5-nuclease assays with standard protocols. Associations between genotypes and KTD were tested by univariate and multivariate logistic regression analyses.nnnRESULTSnKTD was diagnosed in 19 of the 190 (10%) patients. Univariate and multivariate analyses showed a significant association between KTD and genotype CC at position -24 CC (adjusted odds ratio [OR], 20.08; 95% confidence interval [CI], 1.711-235.7; P= .017) and genotype AA at position 1249 (adjusted OR, 16.21; 95% CI, 1.630-161.1; P= .017) of ABCC2. Multivariate analysis showed higher adjusted OR for patients with both homozygotes (adjusted OR, 38.44; 95% CI, 2.051-720.4; P= .015). ABCC2 haplotype -24T and 1249G was a protective haplotype for KTD (OR, 0.098; 95% CI, .002-.603; P= .003nnnCONCLUSIONSnThis is the first study of our knowledge to identify the association between SNPs in ABCC2 and tenofovir-induced KTD in an Asian population. Close monitoring of renal function is warranted in tenofovir-treated patients with these SNPs.

Renal function declines more in tenofovir- than abacavir-based antiretroviral therapy in low-body weight treatment-naïve patients with HIV infection.

Objective To compare the rate of decline of renal function in tenofovir- and abacavir-based antiretroviral therapy (ART) in low-body weight treatment-naïve patients with HIV infection. Design We conducted a single-center retrospective cohort study of 503 Japanese patients who commenced on either tenofovir- or abacavir-based initial ART. Methods The incidence of renal dysfunction, defined as more than 25% fall in estimated glomerular filtration rate (eGFR) from the baseline, was determined in each group. The effect of tenofovir on renal dysfunction was estimated by univariate and multivariate Cox hazards models as the primary exposure. Changes in eGFR until 96 weeks were estimated in both groups with a repeated measures mixed model. Results The median body weight of the cohort was 64 kg. The estimated incidence of renal dysfunction in the tenofovir and the abacavir arm was 9.84 per 100 and 4.55 per 100 person-years, respectively. Tenofovir was significantly associated with renal dysfunction by univariate and multivariate analysis (HRu200a=u200a1.747; 95% CI, 1.152–2.648; pu200a=u200a0.009) (adjusted HRu200a=u200a2.080; 95% CI, 1.339–3.232; p<0.001). In subgroup analysis of the patients stratified by intertertile baseline body weight, the effect of tenofovir on renal dysfunction was more evident in patients with lower baseline body weight by multivariate analysis (≤60 kg: adjusted HRu200a=u200a2.771; 95%CI, 1.494–5.139; pu200a=u200a0.001) (61–68 kg: adjusted HRu200a=u200a1.908; 95%CI, 0.764–4.768; pu200a=u200a0.167) (>68 kg: adjusted HRu200a=u200a0.997; 95%CI, 0.318–3.121; pu200a=u200a0.995). The fall in eGFR was significantly greater in the tenofovir arm than the abacavir arm after starting ART (pu200a=u200a0.003). Conclusion The incidence of renal dysfunction in low body weight patients treated with tenofovir was twice as high as those treated with abacavir. Close monitoring of renal function is recommended for patients with small body weight especially those with baseline body weight <60 kg treated with tenofovir.

Switching tenofovir/emtricitabine plus lopinavir/r to raltegravir plus Darunavir/r in patients with suppressed viral load did not result in improvement of renal function but could sustain viral suppression: a randomized multicenter trial.

Background Whether tenofovir nephrotoxicity is reversible after its withdrawal is unknown. Furthermore, there are no data on the viral efficacy of raltegravir (RAL) plus ritonavir-boosted Darunavir (DRV/r) in patients with suppressed viral load. Methods This multicenter, randomized trial compared renal function and viral efficacy in patients with suppressed viral load treated with RAL+DRV/r and ritonavir-boosted lopinavir (LPV/r) plus tenofovir/emtricitabine (TVD), who had been previously on LPV/r+TVD. The primary endpoint was the proportion of patients with >10% improvement in estimated glomerular filtration rate (eGFR) at 48 weeks calculated with Cockcroft-Gault equation. Results 58 randomized and treatment-exposed patients were analyzed (28 on RAL+DRV/r and 30 on LPV/r+TVD). Greater than 10% improvement in eGFR was noted in 6 (25%) out of 24 with RAL+DRV/r and 3 (11%) of 28 with LPV/r+TVD, and the difference was not statistically significant (p=0.272, 95% CI -0.067 to 0.354). Sensitivity analyses using three other equations for eGFR showed the same results. Urinary β2 microglobulin, a sensitive marker of tenofovir tubulopathy, significantly improved with RAL+DRV/r than with LPV/r+TVD (-271 versus -64 µg/gCr, p=0.026). Per protocol analysis showed that the HIV-RNA was <50 copies/mL at week 48 in all patients of both arms (24 in RAL+DRV and 29 in LPV/r+TVD). Conclusions Switching LPV/r+TVD to RAL+DRV/r did not significantly increase the proportion of patients who showed >10% improvement in renal function among those with relatively preserved eGFR. However, the switch improved urinary β2 microglobulin, suggesting that discontinuation of TDF might be beneficial in the long-term. RAL+DRV/r showed favorable viral efficacy in patients with suppressed viral load. Trial Registration ClinicalTrials.gov NCT01294761 http://clinicaltrials.gov/ct2/show/NCT01294761?term=SPARE&rank=2, Umin Clinical Trials Registry UMIN000005116 http://upload.umin.ac.jp/cgi-open-bin/ctr/ctr.cgi?function=brows&action=brows&type=summary&recptno=R000006083&language=J)

Urinary beta-2 microglobulin and alpha-1 microglobulin are useful screening markers for tenofovir-induced kidney tubulopathy in patients with HIV-1 infection: a diagnostic accuracy study

Kidney tubulopathy is a well-known adverse event of antiretroviral agent tenofovir. A cross-sectional study was conducted to compare the diagnostic accuracy of five tubular markers, with a collection of abnormalities in these markers as the reference standard. The study subjects were patients with HIV-1 infection on ritonavir-boosted darunavir plus tenofovir/emtricitabine with suppressed viral load. Kidney tubular dysfunction (KTD) was predefined as the presence of at least three abnormalities in the following five parameters: β2-microglobulinuria (β2M), α1-microglobulinuria (α1M), high urinary N-acetyl-β-d-glucosaminidase (NAG), fractional excretion of phosphate (FEIP), and fractional excretion of uric acid (FEUA). Receiver operating characteristic curves and areas under the curves (AUC) were estimated, and the differences between the largest AUC and each of the other AUCs were tested using a nonparametric method. The cutoff value of each tubular marker was determined using raw data of 100xa0% sensitivity with maximal specificity. KTD was diagnosed in 19 of the 190 (10xa0%) patients. The AUCs (95xa0% CIs) of each tubular marker were β2M, 0.970 (0.947–0.992); α1M, 0.968 (0.944–0.992); NAG, 0.901 (0.828–0.974); FEIP, 0.757 (0.607–0.907), and FEUA, 0.762 (0.653–0.872). The AUCs of β2M and α1M were not significantly different, whereas those of the other three markers were smaller. The optimal cutoff values with 100xa0% sensitivity were 1,123xa0μg/gCr (β2M, specificity 89xa0%), 15.4xa0mg/gCr (α1M, specificity 87xa0%), 3.58xa0U/gCr (NAG, specificity 46xa0%), 1.02xa0% (FEIP, specificity 0xa0%), and 3.92xa0% (FEUA, specificity 12xa0%). Urinary β2M and α1M are potentially suitable screening tools for tenofovir-induced KTD. Monitoring either urinary β2M or α1M should be useful in early detection of tenofovir nephrotoxicity.

Traditional but not HIV-related factors are associated with nonalcoholic fatty liver disease in Asian patients with HIV-1 infection.

Background The prevalence and factors associated with nonalcoholic fatty liver disease (NAFLD) are largely unknown in HIV-1 monoinfected patients. Methods The present study elucidated the prevalence and factors associated with NAFLD among Asian patients with HIV-1 infection who underwent abdominal ultrasonography between January 2004 and March 2013. Diagnosis of NAFLD was based on the liver to kidney contrast and diffusion in hepatic echogenicity. Uni- and multi-variate logistic regression analyses were applied to estimate factors associated with NAFLD. Results 435 Asian patients free of chronic hepatitis B or C virus infection and without excessive alcohol intake were analyzed. NAFLD was diagnosed in 135 (31%) patients. Obesity (BMI >30 kg/m2) was evident in 18 (4.1%) patients, and BMI was >25 kg/m2 in 103 (24%). Multivariate analysis identified higher BMI (per 1 kg/m2 increment, adjusted ORu200a=u200a1.198; 95% CI, 1.112–1.290; p<0.001), dyslipidemia (adjusted ORu200a=u200a2.045; 95% CI, 1.183–3.538; pu200a=u200a0.010), and higher ALT to AST ratio (per 1 increment, adjusted ORu200a=u200a3.557; 95% CI, 2.129–5.941; p<0.001) as significant factors associated with NAFLD. No HIV-specific variables, including treatment with dideoxynucleoside analogues (didanosine, stavudine, and zalcitabine) and cumulative duration of antiretroviral therapy (ART), were associated with NAFLD. Conclusions The incidence of NALFD among Asian patients with HIV-1 infection is similar to that in Western countries. NAFLD was associated with high BMI, dyslipidemia, and high ALT/AST ratio, but not with HIV-related factors. The results highlight the importance of early recognition and management of NAFLD and traditional factors associated with NAFLD for Asian patients with HIV-1 infection.

Ritonavir-Boosted Darunavir Is Rarely Associated with Nephrolithiasis Compared with Ritonavir-Boosted Atazanavir in HIV-Infected Patients

Background Although ritonavir-boosted atazanavir (ATV/r) is known to be associated with nephrolithiasis, little is known about the incidence of nephrolithiasis in patients treated with ritonavir-boosted Darunavir (DRV/r), the other preferred protease inhibitor. Methods In a single-center cohort, the incidence of nephrolithiasis was compared between HIV-infected patients who commenced DRV/r-containing antiretroviral therapy and those on ATV/r. The effects of ATV/r use over DRV/r were estimated by univariate and multivariate Cox hazards models. Results Renal stones were diagnosed in only one patient (0.86 per 1000 person-years) of the DRV/r group (n=540) and 37 (20.2 per 1000 person-years) of the ATV/r group (n=517). The median [interquartile (IQR)] observation period in the DRV/r group was 27.1 months (IQR 18.1-38.4 months), and 40.6 months (IQR 17.5-42.7) for the ATV/r group. The total observation period was 1,163.6 person-years and 1,829.6 person-years for the DRV/r group and for the ATV/r group, respectively. In the 37 patients on ATV/r who developed nephrolithiasis, the median time from commencement of ATV/r to diagnosis was 28.1 months (IQR 18.4–42.7), whereas nephrolithiasis in the single patient of the DRV/r group occurred 11.2 month after the introduction of DRV/r. ATV/r use over DRV/r was significantly associated with nephrolithiasis by uni- and multivariate analyses (HR=26.01; 95% CI, 3.541–191.0; p=0.001) (adjusted HR=21.47; 95% CI, 2.879–160.2; p=0.003). Conclusion The incidence of nephrolithiasis was substantially lower in patients on DRV/r than those on ATV/r. The results suggest that DRV/r should be selected for treatment of HIV-infected patients at risk of chronic kidney disease.

High-Dose Oral Amoxicillin Plus Probenecid Is Highly Effective for Syphilis in Patients With HIV Infection

BACKGROUNDnIntramuscular benzathine penicillin G (BPG) is widely used for the treatment of syphilis. However, BPG is not available in some countries. This study examined the effectiveness and safety of high-dose oral amoxicillin plus probenecid for the treatment of syphilis in patients with human immunodeficiency virus type 1 (HIV-1).nnnMETHODSnThis retrospective observational study included 286 HIV-infected male patients with syphilis (median age, 36 years; median CD4 count, 389 cells/µL) who were treated with oral amoxicillin 3 g plus probenecid. Syphilis was diagnosed by both serum rapid plasma reagin (RPR) titers ≥8 and positive Treponema pallidum hemagglutination test. Patients with neurosyphilis diagnosed by cerebrospinal fluid examination were excluded. Successful treatment was defined as a at least 4-fold decrement in RPR titer.nnnRESULTSnThe overall treatment efficacy was 95.5% (95% confidence interval [CI], 92.4%-97.7%; 273/286 patients), and efficacy for primary, secondary, early latent, late latent, and unknown duration syphilis was 93.8% (95% CI, 68.1%-99.8%; 15/16), 97.3% (95% CI, 92.9%-99.2%; 142/146), 100% (95% CI, 90.5%-100%; 37/37), 85.7% (95% CI, 58.6%-96.4%; 18/21), and 92.4% (95% CI, 81.9%-97.3%; 61/66), respectively. Treatment duration was mostly 14-16 days (49.7%) or 28-30 days (34.3%), with efficacy of 94.4% (134/142) and 95.9% (94/98), respectively; 96.3% of successfully treated patients achieved a ≥4-fold decrement in RPR titer within 12 months. Adverse events were noted in 28 (9.8%) patients, and 25 of these (89.3%) were successfully treated. Only 6% of patients underwent lumbar puncture.nnnCONCLUSIONSnThe combination of oral amoxicillin 3 g plus probenecid was highly effective and tolerable for the treatment of syphilis in patients with HIV-1 infection.

WHO Antiretroviral Therapy Guidelines 2010 and Impact of Tenofovir on Chronic Kidney Disease in Vietnamese HIV-Infected Patients

Objective The 2010 WHO antiretroviral therapy (ART) guidelines have resulted in increased tenofovir use. Little is known about tenofovir-induced chronic kidney disease (CKD) in HIV-infected Vietnamese with mean body weight of 55 kg. We evaluated the prevalence and risk factors of CKD in this country. Design Cross-sectional study was performed. Methods Clinical data on HIV-infected Vietnamese cohort were collected twice a year. To evaluate the prevalence of CKD, serum creatinine was measured in 771 patients in October 2011 and April 2012. CKD was defined as creatinine clearance less than 60 ml/min at both time points. Multivariate logistic regression was used to determine the factors associated with CKD Results Tenofovir use increased in Vietnam from 11.9% in April 2011 to 40.3% in April 2012. CKD was diagnosed in 7.3%, of which 7% was considered moderate and 0.3% was severe. Multivariate analysis of October-2011 data identified age per year-increase (OR: 1.229, 95%CI, 1.170-1.291), body weight per 1 kg-decrement (1.286, 1.193-1.386), and tenofovir use (2.715, 1.028-7.168) as risk factors for CKD. Conclusions Older age, low body weight and tenofovir use were independent risk factors for CKD in Vietnam. Further longitudinal study is required to evaluate the impact of TDF on renal function in Vietnam and other countries with small-body weight patients.