RESUMO
BACKGROUND: Tubular dysfunction is common in HIV-infected people and detection of proteinuria is essential to identify this problem. In low-income countries, resources for detection of proteinuria using the Kidney Disease Improve Global Outcomes (KDIGO) gold standard urinary protein/creatinine ratio (uPCR) is rarely possible, and use of the protein reagent strip (PRS) could be an option in these places. The aims of this study were to establish the concordance between PRS and uPCR to detect tubular proteinuria in HIV-infected people, and to assess the sensitivity and specificity of PRS as a diagnostic method in this group. METHODS: A cross-sectional study was conducted to evaluate the correlation between the two techniques to detect protein in urine. Participants were enrolled for a period of 6 months. The measurements were performed in participants who were on highly active antiretroviral therapy (HAART) or prior to the start of treatment. Proteinuria was defined as uPCR ≥ 150 mg/g, and/or ≥ trace on PRS. A phi coefficient was calculated to establish the degree of correlation. We assessed the sensitivity and specificity of PRS compared with uPCR using standard methods. RESULTS: A total of 799 subjects were included. Of these, 737 (92%) were men. The mean age was 32.9 years (±10.1 years). Most (561, 70%) were on antiretroviral treatment. The mean estimated glomerular filtration rate (eGFR) calculated according to Modification of Diet in Renal Disease (MDRD)-4 was 113.0 mL/min (±22.6). Comorbidities included diabetes mellitus (10, 1.3%) and hypertension (17, 2.1%). The prevalence of proteinuria detected by PRS was 8.3% (n = 66) and by uPCR 10.6% (n = 85). The concordance assessed by phi correlation coefficient was 0.70, p < 0.001, with a sensitivity of 51.7% (95% confidence interval [CI] 41%-62%) and specificity 97% (95% CI 39%-97%). CONCLUSIONS: There is a high concordance between detection of proteinuria by PRS and uPCR. Therefore, in low-income countries PRS can be helpful for detecting tubular damage in people infected with HIV.
RESUMO
Proximal renal tubular dysfunction (PRTD) of varying severity has been associated with antiretroviral toxicity, especially related to the use of tenofovir (TDF). The aim of this study was to investigate whether HIV-infected patients who use a tenofovir-based regimen are at increased risk of tubular dysfunction. We conducted an observational, comparative, longitudinal, prospective study. Estimated glomerular filtration rate (eGFR) and markers of tubular damage to assess tubular dysfunction (fractional excretion of phosphate and uric acid, glycosuria, and proteinuria) were measured at baseline and at weeks 12 and 24. Of 111 participants, PRTD was found in 6.3% at week 12 and 9% at week 24, with no statistically significant difference between those on an abacavir (ABC)-containing regimen or a TDF-containing regimen. We also found an increase in triglycerides associated with the ABC-containing regimen compared with the TDF group. The use of an ABC- or TDF-containing regimen was independently associated with tubular dysfunction, but we found no significant differences between these groups, except when TDF was combined with a protease inhibitor. A better and more complete assessment of renal function is needed, because the presence of tubular dysfunction and proteinuria without impairment of eGFR may affect the renal safety of HIV-infected patients.
