Technetium-99m hexamethylpropyleneamine-oxime-labeled leukocyte scintigraphy in inflammatory bowel disease in children.

Technetium Tc 99m-labeled hexamethylpropyleneamine-oxime (Tc-HMPAO) scintigraphy has been evaluated in adults with inflammatory bowel diseases and has shown promising ability to define intensity and extent of disease. To evaluate the method's utility in children, we studied 27 pediatric patients-23 with inflammatory bowel diseases and 4 control subjects without abdominal inflammation. Autologous leukocytes labeled with Tc-HMPAO were reinjected into each patient and serial scans were obtained up to 4 hours later. None of the control subjects had any uptake of Tc-HMPAO by the bowel. Disease localization as defined by the scan correlated well with that visualized in surgical specimens from five patients, at endoscopy in three patients, with barium studies of two patients, and with computed tomography scanning of the abdomen in one patient. A "scan score" was calculated by comparing uptake of tracer in five bowel segments with iliac crest bone marrow activity. Scan score correlated much better with clinical disease activity (correlation coefficient = 0.62) than did the erythrocyte sedimentation rate (correlation coefficient = 0.24). Scintigraphy with Tc-HMPAO appears to be useful in evaluation of disease localization and intensity in children with inflammatory bowel disease.

Pyuria and bacteriuria in urine specimens obtained by catheter from young children with fever.

Results of urinalysis and culture of 2181 urine specimens obtained by catheter from febrile children aged less than 24 months were analyzed to determine the following: (1) an optimal cutoff point in considering a bacterial colony count clinically "significant," (2) the accuracy of leukocyte esterase and nitrite tests in identification of pyuria and bacteriuria, and (3) the utility of pyuria (defined as > or = 10 leukocytes/mm3) in the discrimination of urinary tract infection from asymptomatic bacteriuria. Among 110 urine cultures with > or = 10,000 colony-forming units per milliliter, 92 (84%) had > or = 100,000 CFU/ml, 10 (9%) had 50,000 to 99,000 CFU/CFU/ml and 8 (7%) had 10,000 to 49,000 CFU/ml. Urine specimens with 1000 to 49,000 CFU/ml were more likely than specimens with > or = 50,000 CFU/ml to yield Gram-positive or mixed organisms (36/60 vs 7/109; p < 0.001). A count of < 10 leukocytes/mm3 was almost invariably associated with a sterile culture; a count of > or = 10 leukocytes/mm3 was found in 93 of 102 patients with > or = 50,000 CFU/ml. The dipstick leukocyte esterase test had sensitivities of 52.9% and 66.7% in detecting > or = 10 leukocytes/mm3 and > or = 20 leukocytes/mm3, respectively. The dipstick nitrite test had a sensitivity of 31.4% in detecting bacteriuria (> or = 50,000 CFU/ml). Acute pyelonephritis was diagnosed by a renal scan with dimercaptosuccinic acid labeled with technetium 99m in 50 (77%) of 65 patients with > or = 10 leukocytes/mm3 but in none of five patients with < 10 leukocytes/mm3 (p < 0.01). The findings in these five patients were consistent with colonization of the urinary tract rather than infection. For urine specimens obtained by catheter, we believe that urinary tract infection is best defined by both a leukocyte count > or 10/mm3 and a CFU count > or = 50,000/ml. This definition almost always discriminates among true urinary tract infection, bacteriuria resulting from contamination of the urine specimen, and asymptomatic bacteriuria.

Assessment of biventricular cardiac function in patients with a Novacor left ventricular assist device.

Novacor left ventricular assist devices were implanted in 10 patients. We used blood-pool radionuclide angiography and echocardiography to evaluate the response of the left and right ventricle to the left ventricular assist. Radionuclide angiography was done before and after implantation of the Novacor left ventricular assist devices in all cases. All patients had diffuse left ventricular enlargement; the mean left ventricular ejection fraction before Novacor left ventricular assist device implantation was 17% +/- 7%. After implantation of the Novacor left ventricular assist devices the left ventricular ejection fraction improved to 47% +/- 19%, with the pump on a 1:1 assist ratio (p < 0.005). The right ventricular ejection fraction before the Novacor left ventricular assist device implantation was 21%, which improved to 32% with the Novacor left ventricular assist devices (p < 0.01). Doppler echocardiography was carried out in nine patients with the left ventricular assist devices. In five patients the aortic valve remained closed throughout systole. In four patients partial aortic valve opening was noted. At an assist ratio of 1:3, complete opening of the aortic valve was noted in all cases (n = 9); the left ventricular ejection fraction decreased to 31%. We conclude that the Novacor left ventricular assist device substantially improves both right ventricular ejection fraction and left ventricular ejection fraction, although the aortic valve typically remains closed.

Intra- and interobserver variability in interpretation of DMSA scans using a set of standardized criteria.

A set of criteria was developed to standardize assessment of DMSA renal scintigraphy which were performed to evaluate children for acute pyelonephritis and renal scarring. This study was undertaken to assess intra- and interobserver variability in the interpretation of DMSA renal scintigraphy using these criteria. Renal contours and parenchyma were assessed in three zones. Contours were assessed as normal or abnormal and parenchymal defects were evaluated in terms of character, shape and degree in three regions (upper and lower pole and midzone). Two nuclear medicine physicians blindly reviewed 57 DMSA scintigraphy on two occasions each. Disagreement of each observer's evaluation of the same scintigraphy on two different occasions was described as intraobserver variability, and the comparison between readings by each of the two observers was described as interobserver variability. High levels of intra- (95.9% and 90.6% respectively, p < 0.05) and interobserver agreement (84.4%, p < 0.05) were demonstrated. There were minor differences in inconsistencies between the two kidneys or different kidney zones. We conclude that standardization of criteria resulted in higher intra- and interobserver consistency in interpretation of DMSA scintigraphy.