Leucine-Rich Alpha-2-Glycoprotein (LRG-1) as a Potential Kidney Injury Marker in Kidney Transplant Recipients.

BACKGROUND Kidney transplantation is the treatment of choice for most patients with end-stage renal disease. To improve patient and transplant survival, non-invasive diagnostic methods for different pathologies are important. Leucine-rich alpha-2-glycoprotein (LRG-1) is an innovative biomarker that is elevated in cases of angiogenesis, inflammation, and kidney injury. However, there are limited data about the diagnostic role of LRG-1 in kidney transplant recipients. The aim of this study was to evaluate the association between serum LRG-1, urine LRG-1, and kidney transplant function and injury. MATERIAL AND METHODS We enrolled 35 kidney transplant recipients in the study. LRG-1 in the serum and urine was detected using ELISA. We evaluated the correlation of serum and urine LRG-1 with traditional serum and urine kidney injury markers. RESULTS A higher level of serum LRG-1 correlates with a higher level of urine LRG-1. Serum LRG-1 has a positive correlation with transplant age, serum urea, serum creatinine, serum cystatin C, proteinuria, and fractional excretion of sodium (FENa) and a negative correlation with hemoglobin and estimated glomerular filtration rate (eGFR). Urine LRG-1 has a positive correlation with serum cystatin C, proteinuria, and urine neutrophil gelatinase-associated lipocalin (NGAL). CONCLUSIONS Higher levels of serum and urine LRG-1 are associated with kidney transplant injury and functional deterioration. Thus, LRG-1 might be also as a biomarker for tubular dysfunction in patients after kidney transplantation.

Predictors of Hyperuricemia after Kidney Transplantation: Association with Graft Function.

BACKGROUND: In kidney transplant recipients (KTR), hyperuricemia (HU) is a commonly-observed phenomenon, due to calcineurin inhibitors and reduced kidney graft function. Factors predicting HU, and its association with graft function, remains equivocal. METHODS: We conducted a retrospective longitudinal study to assess factors associated with HU in KTR, and to determine risk factors associated with graft function, measured as glomerular filtration rate (GFR). Moreover, GFR > 60 mL/min/1.73 m2 was considered normal. HU was defined as a serum uric acid level of > 416 µmol/L (4.70 mg/dL) in men and >357 µmol/L (4.04 mg/dL) in women, or xanthine-oxidase inhibitor use. We built multiple logistic regression models to assess predictors of HU in KTR, as well as the association of demographic, clinical, and biochemical parameters of patients with normal GFR after a three-year follow-up. We investigated the effect modification of this association with HU. RESULTS: There were 144 patients (mean age 46.6 ± 13.9), with 42.4% of them having HU. Predictors of HU in KTR were the presence of cystic diseases (OR = 9.68 (3.13; 29.9)), the use of diuretics (OR = 4.23 (1.51; 11.9)), and the male gender (OR = 2.45 (1.07; 5.56)). Being a younger age, of female gender, with a normal BMI, and the absence of diuretic medications increased the possibility of normal GFR. HU was the effect modifier of the association between demographic, clinical, and biochemical factors and a normal GFR. CONCLUSIONS: Factors associated with HU in KTR: Presence of cystic diseases, diuretic use, and male gender. HU was the effect modifier of the association of demographic, clinical, and biochemical factors to GFR.