Combined use of urinary alpha1-microglobulin and 99mTc DMSA scintigraphy in the diagnosis and follow-up of acute pyelonephritis and cystitis in children.
OBJECTIVE
In the absence of specific symptomatology in children and neurogenic bladder disease patients, the early diagnosis of acute pyelonephritis is a challenge. The aim of the present study was to determine if dimercaptosuccinic acid (DMSA) lesion-positive (acute pyelonephritis) patients have elevated urinary alpha1-microglobulin (alpha1-MG) excretion (no false negatives) and if DMSA lesion-negative (cystitis) patients have normal urinary alpha1-MG excretion (no false positives).


METHODS
A selected population of 62 children above 3 months of age with a proven urinary tract infection were administered a DMSA scan. A control scan was performed after the acute phase of the illness, and the diagnosis of pyelonephritis (n = 44) was made retrospectively. The urinary alpha1-MG was determined by immunonephelometry.


RESULTS
The urinary alpha1-MG-creatinine ratio was highly sensitive (98%) and specific (100%) and correlated with the DMSA scintigraphy images. Only 1 of the 44 patients with pyelonephritis and all of the cystitis patients (n = 18) had a normal urinary alpha1-MG (<10 mg/g). The drop in absolute DMSA uptake correlated significantly (r = 0. 758, p < 0.001) with the urinary alpha1-MG-creatinine ratio. The urinary alpha1-MG-creatinine ratio was significantly higher (p < 0. 02) in bilateral than in unilateral pyelonephritis.


CONCLUSIONS
DMSA lesion-positive (acute pyelonephritis) patients have elevated urinary alpha1-MG excretion and DMSA lesion-negative (cystitis) patients have normal urinary alpha1-MG excretion.
Everaert
K
K
Department of Urology, University Hospital of Ghent, Belgium. karel.everaert@rug.ac.be
Raes
A
A
Hoebeke
P
P
Samijn
W
W
Delanghe
J
J
Vande Wiele
C
C
Vande Walle
J
J
D000208:Acute Disease; D000510:Alpha-Globulins / Q000652:urine*; D002648:Child; D002675:Child, Preschool; D003404:Creatinine / Q000652:urine; D003556:Cystitis / Q000000981:diagnostic imaging* / Q000652:urine; D003937:Diagnosis, Differential; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D007275:Injections, Intravenous; D008297:Male; D009391:Nephelometry and Turbidimetry; D011704:Pyelonephritis / Q000000981:diagnostic imaging* / Q000652:urine; D011877:Radionuclide Imaging; D019275:Radiopharmaceuticals; D012189:Retrospective Studies; D012680:Sensitivity and Specificity; D019783:Technetium Tc 99m Dimercaptosuccinic Acid
D000510:Alpha-Globulins; D019275:Radiopharmaceuticals; C016001:alpha-1-microglobulin; D019783:Technetium Tc 99m Dimercaptosuccinic Acid; D003404:Creatinine