Imaging of the peritoneum evaluated by 99mTc-icodextrin scintigraphy in peritoneal dialysis patients: preliminary data.

AIM: In this study, we proposed a peritoneal scintigraphy with a different marker, the 99mTechnetium-Icodextrin, to evaluate the distribution of the dialysate within the peritoneal cavity in peritoneal dialysis (PD) patients. METHODS: 99mTc-Icodextrin scintigraphy was performed in 16 PD patients. 0.5 ml of 7.5% Icodextrin solution was labeled with 74 megabecquerel (MBq) of 99mTc and then added to 2,000 ml of dialysate solution (2.5% dextrose). The peritoneum scintigraphy was performed by a SPECT gamma camera with the peritoneal cavity filled and after the complete drainage of the radio compound-dialysate mixture. The images were reviewed for evidence of peritoneal leaks, hernias, loculated fluid collections, and peritoneal membrane adhesions. RESULTS: Abnormal findings were detected by 99mTc-Icodextrin scintigraphy in 4 (25%) out of 16 patients and included retroperitoneal (n = 1), diaphragmatic (n = 1) and inguinal (n = 1) leakages and peritoneal membrane adhesions (n = 1). CONCLUSIONS: Peritoneum scintigraphy with 99mTc-Icodextrin is a useful method to detect some complications occurring during peritoneal dialysis; it offers excellent imaging to assess these complications.

Noninvasive diagnosis of small bowel Crohn's disease: combined use of bowel sonography and Tc-99m-HMPAO leukocyte scintigraphy.

BACKGROUND: Crohn's disease (CD) is frequently localized in the small bowel, with the diagnosis of disease and the assessment of its extension made by ileo-colonoscopy (IC) and small bowel enteroclysis (SBE). Transabdominal bowel sonography (BS) and Tc-99m-HMPAO leukocyte scintigraphy (LS) are increasingly used for the diagnosis of CD because of their minimal invasiveness, reproducibility, and acceptable costs. METHODS: From March 2000 to July 2003, we performed IC, SBE, BS, and LS in 84 patients with either suspected or known small bowel CD. RESULTS: Small bowel CD was present in 50 patients, whereas the other 34 patients received a different diagnosis. Sensitivity, specificity, positive and negative predictive values, and diagnostic accuracy were, respectively, 98%, 97%, 98%, 97%, and 0.97 for SBE; 92%, 97%, 98%, 88%, and 0.94 for BS; and 90%, 93%, 96%, 85%, and 0.92 for LS. In addition, the combined use of BS and LS led to overall sensitivity, specificity, positive and negative predictive values, and diagnostic accuracy of 100%, 93%, 96%, 100%, and 0.97, respectively. BS showed a fair concordance with SBE in terms of location (k = 0.71) and a correlation with the extension of the disease (r = 0.67, P < 0.001). LS showed a concordance with SBE with regard to location in about one-half the population (k = 0.54), whereas it was less effective than SBE in defining disease extension. CONCLUSIONS: BS and LS are 2 accurate techniques for the diagnosis of small bowel CD, and their combined use can be recommended as an early diagnostic approach to patients in which the disease is suspected. SBE remains the best procedure for the definition of the location and extension of the disease.

Per-rectal portal scintigraphy is complementary to ultrasonography and endoscopy in the assessment of portal hypertension in children with chronic cholestasis.

UNLABELLED: We evaluated the clinical usefulness of 99mTc-pertechnetate per-rectal portal scintigraphy (PPS) in the assessment of portal circulation in children with chronic cholestasis. METHODS: PPS percentage shunt index (%SI) (the amount of radionuclide that shunts the liver and reaches the systemic blood after injection in the rectum) was measured in 22 children (mean age, 7.2 +/- 4.9 y) and compared with established clinical, laboratory, and endoscopic and imaging parameters of portal hypertension (PH). Fourteen children had surgically treated biliary atresia, and 8 had chronic intrahepatic cholestasis. Six clinically well children served as control subjects. RESULTS: The %SI was 14.3 +/- 3.1 and 34.7 +/- 18.8 in controls and in patients, respectively (P < 0.01). A cutoff of 19% correctly allocated 100% of controls and 86% of patients. Mean %SI values were significantly higher in patients with biliary atresia, a high risk of pretransplantation death, esophageal varices (EV) at endoscopy, and an abnormal value for the ratio of lesser omentum thickness to abdominal aorta diameter (LO/Ao) at ultrasonography. Correlations between %SI values and several ultrasonographic continuous variables were statistically significant only for LO/Ao ratios (r = 0.51; P = 0.005) and spleen longitudinal diameters (r = 0.53; P = 0.01). The presence of EV could correctly be predicted only when values of %SI were greater than 30% (100% specificity; 56% sensitivity). Endoscopic and PPS findings agreed for a diagnosis of PH with EV in 3 of 7 patients with normal or borderline ultrasonographic LO/Ao ratios. PPS patterns and %SI values became normal in 3 children who underwent liver transplantation. CONCLUSION: In children with chronic cholestasis, PPS may be an advantageous, minimally invasive tool complementary to ultrasonography and endoscopy for better assessment and follow-up of PH before and after liver transplantation.

Noninvasive investigation of hepatopulmonary syndrome in children and adolescents with chronic cholestasis.

Early detection of hepatopulmonary syndrome (HPS) may be delayed because of invasiveness of the diagnostic procedures. In this pilot study, we prospectively investigated the usefulness of determining transcutaneous O(2) tension after 100% O(2) (TcPO(2)100) breathing using a transcutaneous hyperoxia test (THT) in 11 children with chronic cholestasis and without primary cardiopulmonary disease. These patients also underwent alveolar-arterial O(2) gradient testing (AaDO(2)) at an inspired oxygen fraction (FiO(2)) of 0.21, lung scintiscan, and contrast transthoracic echocardiography (TTE). Three of them had a liver transplantation because of the downhill course of their liver disease and respiratory status. THT transcutaneous O(2) tension at 21% FiO(2) (TcPO(2)21) was 75 +/- 13 mm Hg, and increased to 488 +/- 106 mmHg after 100% O(2) breathing (TcPO(2)100). Both mean values were not significantly different from those found in 8 age-matched controls (P = 0.9 and P = 0.5, respectively). However, one patient, in spite of her stable liver function, showed an abnormal TcPO(2)21 and TcPO(2)100 (45 mmHg and 210 mmHg, respectively). This same subject was also the only patient with abnormalities of AaDO(2) (54.2 mm Hg; normal value, < 20 mm Hg), lung scintiscan (brain/lung ratio of technetium-99 fixation (B/L SI) = 9, normal value < 1), and TTE, suggesting intrapulmonary vasodilatations and shunts. Given the clinical development of cyanosis and platypnea, all criteria for HPS were fulfilled, and timing of her liver transplantation was therefore accelerated. This resulted in HPS regression. In children with chronic cholestasis, repeated transcutaneous bedside measurements are a rapid and reliable noninvasive test for characterizing the severity of abnormal oxygenation, and may prove useful also in liver posttransplantation monitoring.