Do tests devised to detect recent HIV-1 infection provide reliable estimates of incidence in Africa?

The objective of this study was to assess the performance of 4 biologic tests designed to detect recent HIV-1 infections in estimating incidence in West Africa (BED, Vironostika, Avidity, and IDE-V3). These tests were assessed on a panel of 135 samples from 79 HIV-1-positive regular blood donors from Abidjan, C?te d'Ivoire, whose date of seroconversion was known (Agence Nationale de Recherches sur le SIDA et les Hépatites Virales 1220 cohort). The 135 samples included 26 from recently infected patients (< or =180 days), 94 from AIDS-free subjects with long-standing infection (>180 days), and 15 from patients with clinical AIDS. The performance of each assay in estimating HIV incidence was assessed through simulations. The modified commercial assays gave the best results for sensitivity (100% for both), and the IDE-V3 technique gave the best result for specificity (96.3%). In a context like Abidjan, with a 10% HIV-1 prevalence associated with a 1% annual incidence, the estimated test-specific annual incidence rates would be 1.2% (IDE-V3), 5.5% (Vironostika), 6.2% (BED), and 11.2% (Avidity). Most of the specimens falsely classified as incident cases were from patients infected for >180 days but <1 year. The authors conclude that none of the 4 methods could currently be used to estimate HIV-1 incidence routinely in C?te d'Ivoire but that further adaptations might enhance their accuracy.     

Estimating incidence of HIV infection in childbearing age African women using serial prevalence data from antenatal clinics

Ades and Medley provided the first flexible method for estimating age‐ and time‐specific HIV incidence using HIV prevalence data collected among pregnant women and adjusting for the effect of differential selection between infected and uninfected women. This paper extends the approach proposed by these authors. We used a parametric model that allows the relative inclusion rate to depend on both age, calendar time, and duration of HIV infection. We developed a two dimensional penalized log‐likelihood approach for estimating time‐ and age‐specific incidence using a binomial likelihood function and a quadratic roughness penalty which allows smoothing over both age and time. Identifiability of the model parameters and effect of sample size are studied through simulations. The method is illustrated using prenatal HIV testing data recorded from 1995 to 2002 in Abidjan, Côte d'Ivoire, to estimate the HIV annual incidence rate among women aged 12–40 year old, from the beginning of the epidemic to 2002. We show that estimated incidence rates are highly dependent on hypotheses made to model the relative inclusion rate. Despite this dependency, the application of the method leads to new and accurate findings on HIV incidence qualitative features in Abidjan. We highlight the relevance of such a method in monitoring the dynamics of HIV epidemic in Africa which is essential for planning vaccine trials and future treatment needs, and for assessment of prevention policy. Copyright © 2006 John Wiley & Sons, Ltd.     

HIV infection and tobacco smoking behaviour: prospects for prevention? ANRS CO3 Aquitaine Cohort, 2002.

OBJECTIVE: To provide up-to-date and covariate-specific estimates on tobacco smoking prevalence in a representative cohort of French human immunodeficiency virus (HIV) 1 infected patients in 2002. DESIGN: We conducted a cross-sectional analysis of the Aquitaine Cohort of HIV-infected patients. A logistic regression model was used to estimate associations between regular tobacco smoking and sex, age, HIV transmission categories, duration and immuno-virological status of HIV infection and duration of antiretroviral therapy. Smoking prevalence estimates were compared with the general French population values after stratification on age and sex. RESULTS: Among 2036 patients included in the analysis, 51% were regular smokers (95%CI 49-53). Smoking prevalence was significantly higher with younger age (OR 1.7 among those < or = 45 years of age), among injecting drug users (OR 4.3), among those whose infection was not controlled (OR 1.2) and those whose HIV infection had been diagnosed for > or = 5 years (OR 1.5). The main difference with the general population was the peak smoking prevalence among HIV-positive patients infected through injecting drug use. CONCLUSIONS: HIV-infected patients are highly exposed to tobacco smoking, which is implicated in multiple conditions occurring in the course of HIV infection. Adapted smoking cessation programmes should become one of the priorities of the medical care of HIV-infected individuals.     

Sonographic Assessment of Renal Size in Healthy Adults

Objective

To assess the normal sonographic values of renal length and cortical thickness in healthy adults and establish reference ranges in our population for comparison when examining renal disease.

Subjects and Methods

Sonographic assessment of renal length and cortical thickness were performed from January 2006 to December 2011 in 252 healthy individuals who were self-referred to the El-Reshaid Renal Clinic in Kuwait. They were screened for the absence of renal abnormalities. Weight and height were measured, and body mass index (BMI) and body surface area calculated. Patients were divided into 5 age groups: 18–30, 31–40, 41–50, 51–60 and 61–80 years, in order to generate reference graphs for renal length and cortical thickness.

Results

The mean renal lengths for the right and left kidney were 10.68 ± 1.4 and 10.71 ± 1.0 cm, respectively (p = 0.56) without a significant change with age. The minimum cortical thickness was 0.6 cm. The renal length correlated with the weight of the patients (p < 0.01) and their BMI (p < 0.01) but not with their height. There was no difference in renal size or cortical thickness in patients older than 60 years despite an age-related decline in the glomerular filtration rate (p < 0.001).

Conclusions

Renal length and cortical thickness did not vary significantly with age. Renal length correlated well with weight and BMI but not with height. Hence, establishing normal ranges of renal parameters is essential for comparison in situations where possible renal disease is being investigated.Key Words: Renal disease, Ultrasound, Renal length, Cortical thickness