Rachael Jones

Renal dysfunction with tenofovir disoproxil fumarate-containing highly active antiretroviral therapy regimens is not observed more frequently: a cohort and case-control study.

Background:Tenofovir disoproxil fumarate (tenofovir DF), the first nucleotide analogue reverse transcriptase inhibitor approved for the treatment of HIV infection, has been associated with renal dysfunction in isolated cases. We investigated the overall incidence and risk of renal dysfunction in individuals receiving tenofovir DF and compared this with other antiretrovirals. Methods:Data from the Chelsea and Westminster cohort were analyzed to reveal HIV-positive individuals with a creatinine value greater than 120 μmol/L at any time, the upper limit of normal used by our reference laboratory. These individuals were classified according to antiretroviral exposure and time exposed. A matched case-control study was performed comparing patients who had received tenofovir DF and subsequently developed a creatinine value greater than 120 μmol/L against controls who had been treated with tenofovir DF and had not experienced a creatinine elevation. Results:Of 4183 HIV-positive patients, 1175 were identified as having a recorded creatinine value >120 μmol/L. Comparison of antiretroviral-naive patients and patients exposed to tenofovir DF- and non-tenofovir DF-containing regimens revealed a lower rate ratio and probability of developing a creatinine value >120 μmol/L in patients exposed to tenofovir DF (rate ratio vs. no antiretrovirals = 0.22, 95% confidence interval [CI]: 0.07-0.69; P < 0.001) with no significant difference between HAART regimens, corrected for duration of exposure. Of the 1058 individuals who were exposed to tenofovir DF, 84 (8%) patients experienced a creatinine value >120 μmol/L subsequent to exposure. An alternative etiology of renal dysfunction was found in 75 (90%) of these individuals. Conclusions:Tenofovir DF is not associated with renal dysfunction more frequently than other antiretroviral drugs, and the occurrence of renal dysfunction in this context is usually attributable to other causes.

Predictors of Renal Outcome in HIV-Associated Nephropathy

BACKGROUND Human immunodeficiency virus (HIV)-associated nephropathy (HIVAN) is an important cause of end-stage renal disease among African American patients. This study was performed to study the epidemiology of HIVAN in a predominantly black African population and the impact of highly active antiretroviral therapy and other factors on the development of end-stage renal disease. METHODS We retrospectively identified all patients with HIVAN, defined by biopsy or strict clinical criteria, in 8 clinics in the United Kingdom. Baseline renal function, HIV parameters, renal pathological index of chronic damage, and responses to highly active antiretroviral therapy were analyzed, and factors associated with adverse renal outcome were identified. RESULTS From 1998 through 2004, we studied 16,834 patients, 61 of whom had HIVAN. HIVAN prevalence in black patients was 0.93%, and HIVAN incidence in those without renal disease at baseline was 0.61 per 1000 person-years. After a median of 4.2 years, 34 patients (56%) had developed end-stage renal disease. There were no significant differences in renal function and HIV parameters at baseline, time to initiation of highly active antiretroviral therapy, and rates of HIV RNA suppression between the 20 patients who developed end-stage renal disease >3 months after receiving the HIVAN diagnosis and the 23 patients who maintained stable renal function. However, the index of chronic damage score was significantly higher in those who developed end-stage renal disease (P < .001), and an index of chronic damage score >75 was associated with shorter renal survival (P < .001). CONCLUSIONS Whereas overall patient survival suggested an important benefit of highly active antiretroviral therapy, no additional renal benefit of early initiation of highly active antiretroviral therapy or viral suppression could be demonstrated in this large cohort of patients with established HIVAN. Severity of chronic kidney damage, as quantified by biopsy, was the strongest predictor of renal outcome.

Antiretrovirals and the kidney in current clinical practice: Renal pharmacokinetics, alterations of renal function and renal toxicity

Assessment of renal function in HIV-positive patients is of increasing importance in the context of ageing and associated comorbidities. Exposure to nephrotoxic medications is widespread, and several commonly used antiretroviral drugs have nephrotoxic potential. Moreover, specific antiretrovirals inhibit renal tubular transporters resulting in the potential for drug–drug interactions as well as increases in serum creatinine concentrations, which affect estimates of glomerular filtration rate in the absence of changes in actual glomerular filtration rate. This review explores the effects of antiretroviral therapy on the kidney and offers an understanding of mechanisms that lead to apparent and real changes in renal function.

HIV testing in non-traditional settings--the HINTS study: a multi-centre observational study of feasibility and acceptability.

Background UK guidelines recommend routine HIV testing in healthcare settings if the local diagnosed HIV prevalence >2/1000 persons. This prospective study assessed the feasibility and acceptability, to patients and staff, of routinely offering HIV tests in four settings: Emergency Department, Acute Care Unit, Dermatology Outpatients and Primary Care. Modelling suggested the estimated prevalence of undiagnosed HIV infection in attendees would exceed 1/1000 persons. The prevalence identified prospectively was not a primary outcome. Methods Permanent staff completed questionnaires assessing attitudes towards routine HIV testing in their workplace before testing began. Subsequently, over a three-month period, patients aged 16–65 were offered an HIV test by study staff. Demographics, uptake, results, and departmental activity were collected. Subsets of patients completed questionnaires. Analyses were conducted to identify factors associated with test uptake. Findings Questionnaires were received from 144 staff. 96% supported the expansion of HIV testing, but only 54% stated that they would feel comfortable delivering testing themselves, with 72% identifying a need for training. Of 6194 patients offered a test, 4105 (66·8%) accepted (61·8–75·4% across sites). Eight individuals were diagnosed with HIV (0–10/1000 across sites) and all transferred to care. Younger people, and males, were more likely to accept an HIV test. No significant associations were found between uptake and ethnicity, or clinical site. Questionnaires were returned from 1003 patients. The offer of an HIV test was acceptable to 92%. Of respondents, individuals who had never tested for HIV before were more likely to accept a test, but no association was found between test uptake and sexual orientation. Conclusions HIV testing in these settings is acceptable, and operationally feasible. The strategy successfully identified, and transferred to care, HIV-positive individuals. However, if HIV testing is to be included as a routine part of patients’ care, additional staff training and infrastructural resources will be required.

Impact of antiretroviral choice on hypercholesterolaemia events: the role of the nucleoside reverse transcriptase inhibitor backbone

The use of highly active antiretroviral therapy (HAART) has profoundly altered the life expectancy of individuals infected with HIV. Metabolic abnormalities associated with antiretrovirals and cumulative exposure to combination antiretroviral therapy, including dyslipidaemia and insulin resistance, have been linked to an increased risk of myocardial infarction.

Incomplete Reversibility of Estimated Glomerular Filtration Rate Decline Following Tenofovir Disoproxil Fumarate Exposure

Background. Tenofovir disoproxil fumarate (TDF) has been linked to renal impairment, but the extent to which this impairment is reversible is unclear. We aimed to investigate the reversibility of renal decline during TDF therapy. Methods. Cox proportional hazards models assessed factors associated with discontinuing TDF in those with an exposure duration of >6 months. In those who discontinued TDF therapy, linear piecewise regression models estimated glomerular filtration rate (eGFR) slopes before initiation of, during, and after discontinuation of TDF therapy. Factors associated with not achieving eGFR recovery 6 months after discontinuing TDF were assessed using multivariable logistic regression. Results. We observed declines in the eGFR during TDF exposure (mean slopes, −15.7 mL/minute/1.73 m2/year [95% confidence interval {CI}, −20.5 to −10.9] during the first 3 months and −3.1 mL/minute/1.73 m2/year [95% CI, −4.6 to −1.7] thereafter) and evidence of eGFR increases following discontinuation of TDF therapy (mean slopes, 12.5 mL/minute/1.73 m2/year [95% CI, 8.9–16.1] during the first 3 months and 0.8 mL/minute/1.73 m2/year [95% CI, .1–1.5] thereafter). Following TDF discontinuation, 38.6% of patients with a decline in the eGFR did not experience recovery. A higher eGFR at baseline, a lower eGFR after discontinuation of TDF therapy, and more-prolonged exposure to TDF were associated with an increased risk of incomplete recovery 6 months after discontinuation of TDF therapy. Conclusions. This study shows that a decline in the eGFR during TDF therapy was not fully reversible in one third of patients and suggests that prolonged TDF exposure at a low eGFR should be avoided.

Comparison of CKD-EPI and MDRD to estimate baseline renal function in HIV-positive patients

BACKGROUND Renal dysfunction is common in HIV-positive patients, and guidelines suggest regular monitoring of renal function with estimated glomerular filtration rate (eGFR) and urinalysis. It is unknown whether Chronic Kidney Disease Epidemiological Collaboration (CKD-EPI) or Modification of Diet in Renal Disease (MDRD) provide better estimates of glomerular filtration rate (GFR) in this population. METHODS We compared the CKD-EPI and MDRD equations to estimate GFR at baseline in 20,132 HIV-positive individuals in the UK CHIC cohort. Kappa statistics and Bland-Altman plots were used to assess agreement between the two estimates and Kaplan-Meier plots and Cox regression analysis to describe mortality patterns. RESULTS At baseline, median eGFR was 100 (87, 112) (CKD-EPI) and 94 (83, 108) (MDRD) (mL/min/1.73 m(2)). Good overall agreement between CKD-EPI- and MDRD-defined eGFR bands was observed (Kappa = 0.71, 95% confidence interval: 0.70-0.72). Of the 367 patients with eGFR MDRD 30-59, 57 (15.5%) were categorized as eGFR 60-89 by CKD-EPI. After adjustment for covariates, eGFR <60 (CKD-EPI), eGFR <30 (MDRD) and eGFR ≥105 (both formulae) were significantly associated with an increased risk of death. Mortality in patients classified as having eGFR 60-89 by CKD-EPI and eGFR 30-59 by MDRD more closely resembled mortality of patients who had eGFR 60-89 by both formulae. CONCLUSIONS MDRD and CKD-EPI equations showed a high degree of agreement in stratifying patients by baseline eGFR. CKD-EPI estimates of GFR <60 at baseline are more strongly associated with mortality than MDRD estimates of GFR <60, supporting the concept that MDRD may have overestimated the severity of renal impairment in these patients. Our findings support the use of CKD-EPI in HIV-positive individuals.

Baseline Kidney Function as Predictor of Mortality and Kidney Disease Progression in HIV-Positive Patients

Background Chronic kidney disease (CKD) is associated with increased all-cause mortality and kidney disease progression. Decreased kidney function at baseline may identify human immunodeficiency virus (HIV)-positive patients at increased risk of death and kidney disease progression. Study Design Observational cohort study. Setting & Participants 7 large HIV cohorts in the United Kingdom with kidney function data available for 20,132 patients. Predictor Baseline estimated glomerular filtration rate (eGFR). Outcomes Death and progression to stages 4-5 CKD (eGFR <30 mL/min/1.73 m2 for >3 months) in Cox proportional hazards and competing-risk regression models. Results Median age at baseline was 34 (25th-75th percentile, 30-40) years, median CD4 cell count was 350 (25th-75th percentile, 208-520) cells/μL, and median eGFR was 100 (25th-75th percentile, 87-112) mL/min/1.73 m2. Patients were followed up for a median of 5.3 (25th-75th percentile, 2.0-8.9) years, during which 1,820 died and 56 progressed to stages 4-5 CKD. A U-shaped relationship between baseline eGFR and mortality was observed. After adjustment for potential confounders, eGFRs <45 and >105 mL/min/1.73 m2 remained associated significantly with increased risk of death. Baseline eGFR <90 mL/min/1.73 m2 was associated with increased risk of kidney disease progression, with the highest incidence rates of stages 4-5 CKD (>3 events/100 person-years) observed in black patients with eGFR of 30-59 mL/min/1.73 m2 and those of white/other ethnicity with eGFR of 30-44 mL/min/1.73 m2. Limitations The relatively small numbers of patients with decreased eGFR at baseline and low rates of progression to stages 4-5 CKD and lack of data for diabetes, hypertension, and proteinuria. Conclusions Although stages 4-5 CKD were uncommon in this cohort, baseline eGFR allowed the identification of patients at increased risk of death and at greatest risk of kidney disease progression.

A prospective evaluation of VEGF-targeted treatment cessation in metastatic clear cell renal cancer

BACKGROUND Vascular endothelial growth factor (VEGF)-targeted therapy is administered continuously until progression in metastatic clear cell renal cancer (mRCC). The role of intermittent therapy is under investigation. Preclinical data raise concerns about this approach. MATERIALS AND METHODS This study combined the data from three similar phase II studies investigating VEGF-targeted therapy prior to planned nephrectomy for untreated mRCC (European Union Drug Regulating Authorities Clinical Trials 2006-004511-21, 2006-006491-38 and 2009-016675-29). The significance of progression during the planned treatment break (median 4.3 weeks) was assessed. RESULTS Sixty-two patients had a structured treatment interruption for nephrectomy after achieving clinical benefit from treatment and restarted therapy. Twenty-three of these patients (37%) progressed (Response Evaluation Criteria In Solid Tumors v1.1) on the first scan after the treatment break. Subsequent stabilisation of disease occurred in 16 of the 23 (70%) progressing patients when the same VEGF tyrosine kinase inhibitor (TKI) was reintroduced. Baseline characteristics, such as the Memorial Sloan Kettering Cancer Centre prognostic score, did not predispose to the development of this progression. Progression during the treatment break was associated with an increased risk of death on multivariate analysis {hazard ratio (HR) 5.56; [95% confidence interval 2.29-13.5], P < 0.01}. Sequential fluorodeoxyglucose positron emission tomography showed a rebound in metabolic activity during the treatment break. CONCLUSIONS Progression during planned VEGF TKI treatment interruptions is frequent and associated with a poor prognosis. Treatment cessation should be pursued with caution.

Screening for Chlamydia trachomatis

Opportunistic approaches have little evidence to support them