Split renal function in young children with unilateral pelvi-ureteric junction obstruction using [99m]Tc-DTPA or [99m]Tc-MAG[3]

Cases of unilateral hydronephrosis in pediatric patients are mostly due to pelvi-ureteric junction obstruction [PUJO] that causes hindrance in the drainage of urine outflow, leading to kidney function impairment The impaired excretory drainage is expected to have diminished or normal split renal function [SRF] on the affected side. However, in a significant number of patients with severe PUJO an elevated SRF can be found. The aim of this work was to estimate the frequency of various grades of SRF in children with PUJO. Secondly, to find out whether there is a difference between [99m]Tc-DTPA or[99m]Tc-MAG3 in assessing the SRF in these children. Fifty-eight children with unilateral PUJO referred for dynamic renography were included in this study on retrospective basis. Twenty-four patients underwent dynamic renography using [99m]Tc-DTPA while 34 were evaluated using [99m]Tc-MAG3. For both [99m]Tc-DTPA and [99m]Tc-MAG3, the dynamic renography started by perfusion phase [1 frame/ sec for 1 min] followed by 15-sec frames for 29 minutes. In all patients frusemide was given at a dose of 1mg/kg at 10 minutes post injection, In the DTPA and MAG3 studies, glomerular filtration rate [GFR] and renal plasma flow [ERPF] were estimated respectively and SRF was calculated from both figures. The normal range for SRF was considered 45% to 55%, In all patients, diagnostic ultrasound was done prior to isotopic renography. The mean age of the studied children was 18 +/- 10 months. The children in the DTPA and MAG3 groups were age and sex-matched. In the DTPA group 25% of the patients had a diminished SRF [< 45%], [46%] had normal SRF and 29% showed paradoxical SRF [> 55%]. In the MAG3 group, 32% of patients had diminished SRF, 41% had normal SRF and 26% showed paradoxical SRF of > 55%. There was no significant difference between DTPA and MAG3 in estimation of SRF in those with normal and suprnormal SRF [P value = 0.0865 and 0,094 respectively] however MGA3 tends to be superior to DTPA in cases of impaired renal function [P value < 0.05. The obstructive renogram patterns define the functional significance of the various grades of hydronephrosis detected by ultrasound. Both [99m]Tc-MAG3 and [99m]Tc-DTPA are comparable and can estimate the SRF in young children with unilateral PUJO, however, in cases of impaired renal function [99m]Tc-MAG3 tends to be better than [99m]Tc-DTPA. Impaired and Paradoxical supranormal split renal function are significantly present in young children with unilateral PUJO

Metabolic super scan in patients with hyperthyroidism: does it have a clinical significance?

Hyperthyroid patients complain of generalized bony aches, which are frequently overlooked due to the more prominent symptoms from cardiovascular and nervous disturbances. Hyperthyroid patients are expected to have abnormal bone metabolism as part of the generalized hypermetabolic status. To verify the presence of metabolic bone supcrscan features in various groups of hyperthyroidism. Secondly, to correlate these superscan features with the various lab results in hyperthyroid patients. Forty-Five patients confirmed to have hyperthyroidism by clinical and lab results were enrolled in this work. In all patients [99m]Tc-pertechnetate thyroid scan with uptake was acquired. In a different day, total body bone scan was acquired 3 hours post IV injection of 15-25mCi of [99m]Tc-MDP. Serum FT3, FT4, TSH, Ca, ALP and PTH were monitored in all patients as markers of thyroid and bone metabolism. 10 cases with no thyroid diseases were included as a control group. Patients with thyroiditis or long history of antithyroid drugs for more than one year were excluded from the study. The studied patients were subdivided into Graves' disease [n=30], Toxic Nodular Goiter [TNG] [n=10] and Autonomous toxic adenoma [AT] in 5 cases. The TSH for the whole group was 0.003 +/- 0.002IU which was significantly suppressed compared to the control group 1.660 +/- 0.222IU. The TSH values for Graves' were 0.002 +/- 0.001IU, TNG 0.004+0.001IU and 0.007 +/- 0.002IU for AT with significant differences [p<0.001 for all]. The thyroid uptake values for the whole group were 17.24 +/- 4.65% which was significantly higher than controls 2.50 +/- 0.53% [p<0.001]. The uptake for Oravcs' 19.92+2.36% was significantly higher than TNG and AT groups [p<0.001 for both]. Metabolic superscan [MSS] was present in 90% [27/30] of the Graves' cases. On the other hand, MSS was present in only 2 patients [20%] from the TNG and in none from the AT group. There were no significant differences regarding Ca, ALP and PTH between the Graves, and non-Graves' groups [p>0.05 for all]. Disturbances in bone metabolism are present mainly in Graves' disease and not in all cases of hyperthyroidism. The addition of the Bone scan to the diagnostic work-up patients with Gravs' is a sensitive indicator for metabolic bone changes and could help in the future management and follow up for this group of patients