RESUMO
Identifying noninvasive biomarkers of kidney disease is valuable for diagnostic and therapeutic purposes. Hypoxia inducible factor 1 (HIF-1) expression is known to be elevated in the kidneys in several renal disease pathologies. We hypothesized that the urinary HIF-1a mRNA level may be a suitable biomarker for expression of this protein in chronic kidney disease (CKD). We compared HIF-1a mRNA levels from urine pellets of CKD and healthy subjects. To ensure that urinary HIF-1a mRNA is of kidney origin, we examined colocalization of HIF-1a mRNA with two kidney specific markers in urine cells. We found that HIF-1a mRNA is readily quantifiable in urine pellets and its expression was significantly higher in CKD patients compared with healthy adults. We also showed that the urinary HIF-1a mRNA comes primarily from cells of renal origin. Our data suggest that urinary HIF-1a mRNA is a potential biomarker in CKD and can be noninvasively assessed in patients.
Assuntos
Biomarcadores/urina , Fator 1 Induzível por Hipóxia/urina , Insuficiência Renal Crônica/urina , Adulto , Idoso , Caderinas/metabolismo , Creatinina/sangue , Demografia , Feminino , Genes Essenciais , Receptor Celular 1 do Vírus da Hepatite A/genética , Receptor Celular 1 do Vírus da Hepatite A/metabolismo , Humanos , Fator 1 Induzível por Hipóxia/genética , Fator 1 Induzível por Hipóxia/metabolismo , Hibridização in Situ Fluorescente , Rim/metabolismo , Masculino , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Padrões de Referência , Insuficiência Renal Crônica/sangue , Insuficiência Renal Crônica/genéticaRESUMO
Cytodiagnostic urinalysis (CDU) has been used to evaluate causes of kidney allograft dysfunction, such as an acute rejection episode (ARE), calcineurin inhibitor (CNI) toxicity, or polyoma virus infection. We examined the concordance between CDU and allograft biopsy in patients with allograft dysfunction. Between 2002 and 2006, 201 patients had CDU performed within 7 days of a biopsy. The cohort was black (73%) with, male preponderance (59.2%), and an overall mean age of 48±13 years with 46% having received a deceased donor kidney. The induction regimen consisted of either antithymocyte globulin or alemtuzumab. CDU results that demonstrated 5 to 10 lymphocytes per high-power field (HPF) and >20 lymphocytes/HPF had 2.5 increased odds of predicting acute rejection (AR) on biopsy (odds ratio [OR] 2.5; 95% confidence interval [CI] 1.12-5.79; P=.025). In the era of antithymocyte globulin induction, a CDU result demonstrating>5 lymphocytes/HPF had a 4.3 increased odds of predicting AR (CI 1.76-10.50; P=.001). This association was lost with alemtuzumab induction. A positive CDU result for calcineurin inhibitor (CNI) toxicity did not predict CNI nephrotoxcity on biopsy, but a positive CDU for polyoma virus infection predicted polyoma virus nephropathy (OR 22.18; CI: 4.41-111.63; P<.001). In conclusion, CDU is an adjunctive diagnostic tool for kidney transplantation.