Tc-99m DMSA renal scan in first-time versus recurrent urinary tract infection-yield and patterns of abnormalities

Structure and Activities of Nuclear Medicine in Kuwait

The practice of nuclear medicine in Kuwait began in 1965 as a clinic for treating thyroid diseases. The practice developed gradually and until 1981 when the Faculty of Medicine established the Division of Nuclear Medicine in the Department of Radiology, which later became a separate department responsible for establishing and managing the practice in all hospitals of Kuwait. In 1987, a nuclear medicine residency program was begun and it is administered by Kuwait Institute for Medical Specializations originally as a 4-year but currently as a 5-year program. Currently there are 11 departments in the ministry of health hospitals staffed by 49 qualified attending physicians, mostly the diplomats of the Kuwait Institute for Medical Specializations nuclear medicine residency program, 4 academic physicians, 2 radiopharmacists, 2 physicists, and 130 technologists. These departments are equipped with 33 dual-head gamma cameras, 10 SPET/CT, 5 PET/CT, 2 cyclotrons, 1 breast-specific gamma imaging, 1 positron-emitting mammography, 10 thyroid uptake units, 8 technegas machines, 7 PET infusion systems, and 8 treadmills. Activities of nuclear medicine in Kuwait include education and training, clinical service, and research. Education includes nuclear medicine technology program in the Faculty of Allied Health Sciences, the 5-year residency program, medical school teaching distributed among different modules of the integrated curriculum with 14 didactic lecture, and other teaching sessions in nuclear medicine MSc program, which run concurrently with the first part of the residency program. The team of Nuclear Medicine in Kuwait has been active in research and has published more than 300 paper, 11 review articles, 12 book chapters, and 17 books in addition to 36 grants and 2 patents. A PhD program approved by Kuwait University Council would begin in 2016.

Late Recurrent Urinary Tract Infections May Produce Renal Allograft Scarring Even in the Absence of Symptoms or Vesicoureteric Reflux

BACKGROUND

The significance of late urinary tract infections (UTIs) after renal transplantation and their association with scarring and graft dysfunction remains controversial. We sought to define the prevalence of renal scarring in allograft recipients with a history of late recurrent UTIs, to determine whether the presence of vesicoureteric reflux (VUR) confers an increased risk of scarring and to establish whether scarring correlates with graft dysfunction.

METHODS

Among 307 renal allograft recipients, we identified 56 (18%) with late recurrent UTIs (> or =3/year). A total of 32 patients had undergone further investigation by both 2,3 dimercapto-succinic acid single-photon emission computed tomography (99mTc-DMSA SPECT) scan and micturating cystourethrogram (MCUG).

RESULTS

Of the 32 patients, 24 (75%) had scars on 99mTc-DMSA SPECT and 15 (47%) had reflux on MCUG. Thirteen of these 15 patients with reflux (87%) had scars, although there was no significant correlation between number of scars and degree of reflux. Eleven of 17 patients (65%) with UTIs but without VUR had scars, as did 12 of 14 (86%) with previous graft pyelonephritis. The pattern of scarring (typically multiple focal cortical defects) suggested infection as the cause. This pattern was not seen in a contemporary cohort with vascular occlusions and was rarely seen in patients with chronic allograft nephropathy. Scarring was not associated with inferior graft survival (median follow-up, 15 years).

CONCLUSIONS

In patients with late UTIs, renal scarring is a frequent finding. Scarring may occur even in asymptomatic patients without VUR. The lack of an effect on graft survival may reflect successful intervention with prophylactic antibiotics and surveillance urine cultures. Late recurrent UTIs may be damaging to renal allografts, even in the absence of reflux.

Sectorial technetium-99m-dimercaptosuccinic acid scintigraphy for monitoring the effect of extracorporeal piezoelectric lithotripsy for calyceal calculi on regional renal function

OBJECTIVE

To apply a semiquantitative method for analysis of technetium-99m-dimercaptosuccinic acid ((99m)Tc-DMSA) renal scintigraphy for monitoring the effect of extracorporeal piezoelectric lithotripsy (EPL) in patients with calyceal stones on regional kidney function and to check whether EPL had caused any deleterious effect on the target calyceal renal parenchymal function.

PATIENTS AND METHODS

Forty patients (mean age 35 years) suffering from calyceal stones documented by abdominal plain radiography, intravenous urogram or abdominal ultrasound were studied. All patients were treated by EPL. (99m)Tc-DMSA scan was performed before and 4 weeks after EPL. Sector analysis involved calculation of the relative function of the target calyx to the function of the ipsilateral kidney and the relative function of the treated kidney to global renal function.

RESULTS

The stone sizes were 6-11 mm in diameter and 11 were located in the upper, 13 in the middle and 16 in the lower calyx. After EPL, the overall stone clearance rate was 85% (100% for calculi in the upper and middle calyces, 62% for lower calyces). The sector analysis did not show statistically significant change of the relative regional (calyceal) or whole kidney function between the pre- and post-EPL (99m)Tc-DMSA scans. Using sector analysis, EPL appeared to be a safe modality and its usage was not associated with any untoward effect on calyceal or whole kidney function.

CONCLUSION

Sector analysis of (99m)Tc-DMSA renal scan is a simple semiquantitative method for monitoring regional changes of kidney function after EPL for treatment of calyceal stone.