RESUMO
BACKGROUND: Hypercalcemia is highly prevalent in kidney transplant recipients with hyperparathyroidism. However, its long-term impact on graft function is uncertain. METHODS: We conducted a prospective cohort study investigating adverse graft outcomes associated with persistent hypercalcemia (free calcium > 5.2 mg/dL in ≥ 80% of measures) and inappropriately elevated intact parathyroid hormone (> 30 pg/mL) in kidney transplant recipients. Asymptomatic mild hypercalcemia was monitored unless complications developed. RESULTS: We included 385 kidney transplant recipients. During a 4-year (range 1-9) median follow-up time, 62% of kidney transplant recipients presented persistent hypercalcemia. Compared to kidney transplant recipients without hypercalcemia, there were no significant differences in graft dysfunction (10% vs. 12%, p = 0.61), symptomatic urolithiasis (5% vs. 3%, p = 0.43), biopsy-proven calcium deposits (6% vs. 5%, p = 1.0), fractures (6% vs. 4%, p = 0.64), and a composite outcome of urolithiasis, calcium deposits, fractures, and parathyroidectomy indication (16% vs. 13%, p = 0.55). In a subset of 76 kidney transplant recipients, subjects with persistent hypercalcemia had higher urinary calcium (median 84 [43-170] vs. 38 [24-64] mg/day, p = 0.03) and intact fibroblast growth factor 23 (median 36 [24-54] vs. 27 [19-40] pg/mL, p = 0.04), and lower 25-hydroxyvitamin D levels (11.3 ± 1.2 vs. 16.3 ± 1.4 ng/mL, p < 0.001). In multivariate analysis, pretransplant intact parathyroid hormone < 300 pg/mL was associated with a reduced risk of post-transplant hypercalcemia (OR 0.51, 95% CI 0.32-0.80). CONCLUSIONS: Long-term persistent mild hypercalcemia (tertiary hyperparathyroidism) was frequent in kidney transplant recipients in our series. This condition presented with lower phosphate and 25-hydroxyvitamin D, and higher urinary calcium and intact fibroblast growth factor 23 levels compared to kidney transplant recipients without hypercalcemia, resembling a mild form of primary hyperparathyroidism. Despite these metabolic derangements, the risk of adverse graft outcomes was low.
RESUMO
Kidney transplant (KT) is the best treatment for patients who progress to end-stage renal disease. Short-term outcomes in patients with systemic lupus erythematosus (SLE) following KT are not well known. To describe the postoperative outcomes and complications in SLE patients undergoing KT, we conducted a case-control study from 2010 to 2015 including SLE recipients compared to non-SLE controls matched by age and sex. Demographics, comorbidities, donor characteristics, and preoperative tests were retrieved. Main outcomes were 30-day postoperative allograft function, development of infectious or non-infectious complications, and mortality. 68 patients (34 SLE, 34 non-SLE) were included. SLE recipients had median disease duration of 9 years; SLEDAI-2K of 2, and SLICC/ACR damage index of 3; 16 (47%) were taking prednisone (median dose 5 mg daily) before KT. SLE recipients had a lower frequency of diabetes (0 vs. 27%, p = 0.002). No differences were found in the development of any complication (50% SLE vs. 47% non-SLE, p = 1.00); infectious (44% vs. 41%, p = 1.00), or non-infectious (15% vs. 21%, p = 1.00). There were no deaths in either group, and none of the SLE recipients presented lupus disease activity 30 days after the KT. Allograft function determined by serum creatinine, estimated glomerular filtration rate, delayed graft function, and allograft loss was similar in both groups (p > 0.05). There were no differences between SLE recipients with and without complications. Early postoperative outcomes in SLE patients who undergo KT, including allograft function, development of infectious, non-infectious complications, and mortality, are similar to patients without SLE.
