The variation of selective uNGAL levels after robot-assisted partial nephrectomy: Early results of a prospective single center study.

OBJECTIVES: Acute kidney injury (AKI) secondary to nephron-sparing surgery represents a significant problem in order to preserve renal function. Since serum creatinine alone underestimates the early detection of AKI several biomarker have been investigated. Neutrophil Gelatinase-Associated Lipocalin (NGAL) is considered a good biomarker for AKI. MATERIALS AND METHODS: We report our experience in 28 patients affected by localized renal cell carcinoma and submitted to robot-assisted partial nephrectomy (RAPN). In each patient selective urinary NGAL levels were dosed before surgery, then 2 and 48 hours after the procedure, through a ureteral catheter inserted into the excretory axis of the operated kidney. Moreover, we evaluated split renal function of the preserved renal parenchyma by a 99mTC-DTPA renal scintigraphy, performed before surgery and three months later. RESULTS: AKI was diagnosed, according to internationally criteria, in 3 patients (10.7%). The baseline selective urinary NGAL level was 20.02 ng/ml. This level significantly increased after surgery with a selective urinary NGAL level that reached 56.36 ng/ml (p < 0.0001). Moreover, a significant reduction in 99mTC-DTPA clearance of the operated kidneys after three months was detected (p < 0.0001). CONCLUSIONS: Selective urinary NGAL assay represent a sensitive biomarker of acute kidney injury after robotic nephron sparing surgery, capable of predicting the functional outcome of the operated kidney.

Sestamibi scintigraphy, topography, and histopathology of parathyroid glands in secondary hyperparathyroidism.

BACKGROUND: Several imaging techniques presently are available to assess the location of hyperplastic parathyroid glands. The purpose of the present study is to assess the place of dual-phase technetium Tc 99m-sestamibi (MIBI) scintigraphy in the preoperative localization of hyperplastic parathyroid glands in patients with severe secondary hyperparathyroidism (SHPT). METHODS: We studied 35 consecutive adult white hemodialysis patients undergoing a first parathyroidectomy after performing MIBI scintigraphy. Hyperplasia of the parathyroid glands was classified as diffuse (DH) or nodular (NH). Statistical analysis was conducted by comparing patients with MIBI-negative (no focal area of increased uptake) with MIBI-positive (> or = 1 focal area of increased uptake) results and stratifying parathyroid glands according to location (superior and inferior). RESULTS: MIBI scintigraphy showed focal areas of increased uptake in at least 1 gland in 25 patients (71.4%). Total number of focal areas of increased uptake was 42 of 121 glands removed (sensitivity, 34.7%; specificity, 100%). One hundred one glands showed NH and 20 glands showed DH. The 25 patients with MIBI-positive results had 85 pathological glands removed, and the 10 patients with MIBI-negative results had 36 pathological glands removed: in the former, most glands showed NH (77 of 85 glands; 90.6%), and in the latter, 24 of 36 glands showed NH (66.7%; P = 0.004 at chi-square test). The sensitivity of MIBI scintigraphy for distinguishing specific subtypes of hyperplasia was 37.6% (38 of 101 glands) for NH and 20.0% (4 of 20 glands) for DH (P = 0.0005). The following values were significantly greater in inferior compared with superior glands: (1) estimated weight (2.1 +/- 0.8 versus 1.6 +/- 1.2 g; P = 0.04), (2) percentage of MIBI positivity (34 of 42 inferior glands [80.9%] versus 8 of 42 superior glands [19.1%]; P = 0.0001), and (3) percentage of localization permitted by MIBI scintigraphy (34 of 63 inferior glands [54.0%] versus 8 of 58 superior glands [13.8%]; P = 0.0001). Thus, NH, although equally distributed between inferior (53 of 63 glands) and superior (48 of 58 glands) glands, showed a percentage of MIBI positivity significantly greater in inferior (34 of 53 glands [64.1%]) compared with superior glands (8 of 48 glands [16.7%]; P = 0.0001). CONCLUSION: MIBI scintigraphy did not show high sensitivity in identifying hyperplastic glands, although it was able to identify those with NH better than those with DH. Thus, MIBI scintigraphy has limited value preoperatively for patients with SHPT. Estimated weight, percentage of MIBI positivity, and percentage of localization permitted by MIBI scintigraphy were significantly greater in inferior glands.