Estimated glomerular filtration rate is unreliable in detecting renal function loss during follow-up after cystectomy and urinary diversion.

PURPOSE: To evaluate the accuracy of estimated glomerular filtration rate (eGFR) against the reference standard of isotopic GFR (iGFR) in monitoring renal function during follow-up after cystectomy and urinary diversion. METHODS: Patients who had undergone cystectomy and ileal conduit urinary diversion at two centres between August 2001 and August 2006 were identified. eGFR calculated using the MDRD formula was compared to (51)Cr EDTA measured iGFR values measured at similar time-points during follow-up. RESULTS: Six hundred and fourteen paired iGFR and eGFR results were analysed from 166 patients (18% female, median age 70 years). There was a significant difference between paired iGFR and eGFR measurements (p < 0.0001) with a mean bias of +1.8 mls/min/1.73 m(2) (SD 18.0) and a 95% limit of agreement of -33.5 to 37.2 mls/min/1.73 m(2). iGFR and eGFR values converged at a GFR of approximately 45 mls/min/1.73 m(2). 70.6% of patients experienced a loss of renal function greater than expected (>0.58 mls/min/1.73 m(2)/year). In 22.4% of these patients, a decline of greater than 10% in iGFR occurred that was undetected by eGFR measurements, which overestimated GFR. There was no significant relationship between patient height, weight or body mass index and the accuracy of eGFR measurements. CONCLUSIONS: iGFR measurement is recommended following ileal conduit urinary diversion if early signs of renal function loss are to be detected. eGFR overestimates GFR in critically relevant ranges and fails to detect loss in a clinically significant proportion of patients.

Impact of multiple deprivations on detection, progression and interventions in small renal masses (less than 4 cm) in a population based study.

BACKGROUND AND OBJECTIVES: A relatively unknown associations exists between the detection, progression and rate of interventions in small renal masses in the context of socioeconomic status. The study explored the impact of socioeconomic status on the detection, progression and intervention rate in SRMs. PARTICIPANTS AND METHODS: A population-based cohort of patients with SRMs was identified using various hospital databases in well-defined geographical area between January 2007 and December 2011. A list of patients with unique 10-digits Community Health Index (CHI) number and their follow-up was recorded on a pre-designed electronic database sheet. Correlation between the socioeconomic status and detection, progression and pattern of interventions of small renal masses was the primary outcome. The postcode of each patient was identified and linked to the Scottish Index of Multiple Deprivation (SIMD) scoring system, and a deprivation category number assigned to each patient, allowing potential links to become apparent between small renal masses and deprivation. RESULTS: Two hundred and seventeen patients were diagnosed with small renal masses in 150,820 abdominal imaging carried out in a population of 117,600. The detection of SRMs in relation to SIMD status showed no statistically significant differences across different categories. Similarly, interventions, type of surgery and progression remained unaffected by socioeconomic status. The group on active surveillance showed slow or no-growth at a mean follow-up of more than 2 years. CONCLUSIONS: The detection of small renal masses is very small compared with the amount of imaging investigations of abdomen in 5 years in this cohort. Detection, progression and rate of intervention did not differ in different socioeconomic strata of the cohort. The majority of small renal masses on active surveillance did not change or grew in size very slowly when observed over time.

A trigonal bipyramidal uranyl amido complex: synthesis and structural characterization of [Na(THF)2][UO2(N(SiMe3)2)3].

The synthesis and structural characterization of a rare example of a uranyl complex possessing three equatorial ligands, [M(THF)2][UO2(N(SiMe3)2)3] (3a, M = Na; 3b, M = K), are described. The sodium salt 3a is prepared by protonolysis of [Na(THF)2]2[UO2(N(SiMe3)2)4], whereas the potassium salt 3b is obtained via a metathesis reaction of uranyl chloride UO2Cl2(THF)2 (4) with 3 equiv of K[N(SiMe3)2]. A single-crystal X-ray diffraction study of 3a revealed a trigonal-bipyramidal geometry about uranium, formed by two axial oxo and three equatorial amido ligands, with average U=O and U-N bond distances of 1.796(5) and 2.310(4) A, respectively. One of the oxo ligands is also coordinated to the sodium counterion. 1H NMR spectroscopic studies indicate that THF adds reversibly as a ligand to 3 to expand the trigonal bipyramidal geometry. The degree to which the coordination sphere in 3 is electronically satisfied with only three amido donors is suggested by (1) the reversible THF coordination, (2) a modest elongation in the bond distances for a five-coordinate U(VI) complex, and (3) the basicity of the oxo ligands as evidenced in the contact to Na. The vibrational spectra of the series of uranyl amido complexes [UO2(N(SiMe3)2)n]2-n (n = 2-4) are compared, to evaluate the effects on the axial U=O bonding as a function of increased electron density donated from the equatorial region. Raman spectroscopic measurements of the nu 1 symmetric O=U=O stretch show progressive axial bond weakening as the number of amido donors is increased. Crystal data for [Na(THF)2][UO2(N(SiMe3)2)3]: orthorhombic space group Pna2(1), a = 22.945(1) A, b = 15.2830(7) A, c = 12.6787(6) A, z = 4, R1 = 0.0309, wR2 = 0.0524.