Value of TC-99M DMSA scintigraphy in urinary tract infection: comparative study with other imaging modalities

ABSTRACT

Urinary tract infection [UTI] is a common medical problem. It causes considerable morbidity specially if complicated, can cause severe renal damage. The aim of this study is to evaluate value of Tc-99m DMSA in UTI comparing with ultrasound and CT scan. We analyzed a random sample of 63 patients approved to have urinary tract infection. Abdominal ultrasound, CT, and [99m] Tc-DMSA scintigraphy of the kidneys were performed in all patients. Tc-99m DMSA scan showed scintigraphic changes consistent with pyelonephritis in all patients. The involvement was either unilateral in 53 patients [84%] or bilateral in 10 patients [16%]. The number of diseased kidneys were 73/126 [58%], 16/73 kidneys had abnormal unifocal defects [22%], 27/73 kidneys had multifocal defects [37%], while 30/73 kidneys had diffuse hypoactivity [41%]. The sensitivity of CT scan in detecting pyelonephritis was 82.8% while the sensitivity of ultrasound was poor [23.8%] and there was a statistically significant difference between the sensitivity of ultrasound and that of Tc-99m DMSA. Tc-99m DMSA is reliable diagnostic, cost-effective, simple, safe and noninvasive modality and may be taken as a routine procedure for the patients with clinical suspicion of upper UTI whenever the facilities are available