99mTc-DTPA Diuretic Renography with 3 hours late output fraction in the evaluation of hydronephrosis in children

ABSTRACT Objective: Dynamic renal scintigraphy complemented by late gravity assisted postvoid images to 60 minutes is a frequently used diagnostic test in the evaluation of hydrone- phrosis. The objective of this study is to evaluate the effectiveness in acquiring images at 180 minutes to calculate the late output fraction (LOF) of 99mTc-DTPA in the diagno- sis of ureteropelvic junction obstruction (UPJO). Materials and Methods: A retrospective study of 177 patients (196 renal units) of sus- pected cases of clinical UPJO was conducted. The patients were submitted to at least two dynamic renal scintigraphies of 99mTc-DTPA, with the addition of furosemide (F0), with a mean age of 4.3±3.8 years for the first study, and a follow-up of 2.7±2.5 years. Results: For diagnosis based on renal curves, a 100% sensitivity, 82.2% specificity, positive predictive value (PPV) of 10.4% and negative predictive value (NPV) of 100% were estimated. For diagnosis based on LOF, a 100% sensitivity, 96.3% specificity, PPV of 35.7% and NPV of 100% were estimated. Conclusion: A LOF <10% is indicative of UPJO, and a LOF ≥15% is indicative of no UPJO. The data demonstrate that LOF presents equivalent sensitivity and NPV, and higher specificity and PPV in comparison to diagnosis based on renal curves, and is useful in the evaluation and follow-up of suspected cases of UPJO.

99mTc-DTPA Diuretic Renography with 3 hours late output fraction in the evaluation of hydronephrosis in children.

OBJECTIVE: Dynamic renal scintigraphy complemented by late gravity assisted postvoid images to 60 minutes is a frequently used diagnostic test in the evaluation of hydronephrosis. The objective of this study is to evaluate the effectiveness in acquiring images at 180 minutes to calculate the late output fraction (LOF) of 99mTc-DTPA in the diagnosis of ureteropelvic junction obstruction (UPJO). MATERIALS AND METHODS: A retrospective study of 177 patients (196 renal units) of suspected cases of clinical UPJO was conducted. The patients were submitted to at least two dynamic renal scintigraphies of 99mTc-DTPA, with the addition of furosemide (F0), with a mean age of 4.3±3.8 years for the first study, and a follow-up of 2.7±2.5 years. RESULTS: For diagnosis based on renal curves, a 100% sensitivity, 82.2% specificity, positive predictive value (PPV) of 10.4% and negative predictive value (NPV) of 100% were estimated. For diagnosis based on LOF, a 100% sensitivity, 96.3% specificity, PPV of 35.7% and NPV of 100% were estimated. CONCLUSION: A LOF <10% is indicative of UPJO, and a LOF ≥15% is indicative of no UPJO. The data demonstrate that LOF presents equivalent sensitivity and NPV, and higher specificity and PPV in comparison to diagnosis based on renal curves, and is useful in the evaluation and follow-up of suspected cases of UPJO.

Leukocyte-technetium-99m uptake in Crohn's disease: does it show subclinical disease?

AIM: To evaluate inflammatory activity in patients with Crohn's disease (CD) using technetium-99m-hexamethylpropyleneamine oxime (99mTc-HMPAO) granulocyte scintigraphy. METHODS: Twenty patients (7 male and 13 female) with CD and five healthy volunteers were selected for 99mTc-HMPAO granulocyte scintigraphy. The Crohn's Disease Activity Index (CDAI), blood tests and C-reactive protein (CRP) of each patient were performed 7 d before the scintigraphic images. The leukocytes were labeled according to the International Society of Radiolabeled Blood Elements (ISORBE) consensus protocol and the scintigraphic images, including single photon emission computed tomography, were obtained 30 min and 2 h after injection of the radiolabeled leukocytes. RESULTS: The labeling yield of the leukocytes with the lipophilic complex 99mTc-HMPAO was 55.0% +/- 10%. Six of the 20 patients (30%) presented congruent results for the three parameters investigated (CDAI, Scintigraphic Index and CRP). On the other hand, 14 patients (70%) did not show congruent results. There was no significant correlation between the indices analyzed according to the Spearman test (P > 0.05, n = 20). CONCLUSION: The results suggest that 99mTc-HMPAO-labeled leukocyte scintigraphy could be important for determining inflammatory activity in CD even in the absence of clinical symptoms.

Atividade fagocitária do sistema mononuclear fagocitário na gravidez / Phagocytic function of reticuloendothelial system during pregnancy

As alterações imunitárias que ocorrem durante a gravidez são ainda pouco compreendidas. Para determinar a influência da gravidez na atividade fagocitária do sistema mononuclear fagocitário (SMF) foram utilizadas vinte ratas adultas. Os animais foram divididos em dois grupos (n-10): Grupo 1 - controle, Grupo 2 - ratas prenhas. A função do sistema mononuclear fagocitário foi determinada pela captação de enxofre coloidal marcado com 99mTc pelos órgãos do SMF, além de avaliar a permanência do radiofármaco em coágulo sangüíneo. O peso e a radiação de cada amostra foram medidas. Realizou-se também análise histológica desses órgãos. Os resultados foram comparados pelo teste t de Student. Em todos os animais, a captação do radiofármaco foi maior no fígado, seguido pelo baço e pulmão. O coágulo sangüíneo apresentou uma quantidade mínima de radiação. As ratas grávidas registraram menor captação do colóide no fígado e maior captação no pulmão em relação ao grupo controle. Não foram evidenciadas alterações na histoarquitetura desses órgãos. Em rata grávida, a atividade fagocitária do SMF diminuiu no fígado, porém aumentou no pulmão.

Alterations of the immune function during thepregnancy are not well understood. To assess theinfluence of pregnancy on the phagocytic function ofthe reticuloendothelial system twenty adult female ratswere divided into two groups: Group 1 (n=10) –control, Group 2 (n=10) – pregnant rats. The assessmentof the phagocytic function of the reticuloendothelialsystem was by the uptake of sulphur colloid labeled withTc99m by the reticuloendothelial system organs as wellas to assess the permanence of the radio isotope inblood clots. The weights and radioactive levels of thesamples were measured. Histologic analyses of theseorgans were performed as well. The results werecompared using the Student t-test, with significanceat p<0.05. The scintigraphic values were higher in theliver followed by spleen and lung. The blood clotpresented with only a low amount of radiation. Thepregnant rats registered lower radiation levels in theliver and higher in the lung when compared with thecontrol group. The histo-architecture of the studiedorgans did not show any alterations. Pregnancyreduces the phagocytic function of the liver butincreases the role of the reticuloendothelial systemfunction of the lung.

Outcome of apparent ureteropelvic junction obstruction identified by investigation of fetal hydronephrosis.

OBJECTIVES: The purpose of the study was to evaluate the outcome of prenatally detected ureteropelvic junction obstruction (UPJO) managed with a more conservative protocol. METHODS: The records and imaging studies of 77 consecutive neonates with UPJO identified by fetal hydronephrosis were reviewed. A nonoperative approach was attempted in patients with mild/moderate pelvic dilatation, renal units with good function as ascertained by DMSA scan and a non-obstructed pattern on DTPA. Otherwise, the patients were managed surgically by pyeloplasty. Both groups were prospectively followed and the imaging studies were performed before and after the initial approach and at one-year intervals thereafter. RESULTS: Of the 77 infants (85 units), 39 were submitted to surgery (33 pyeloplasty and 7 nephrectomy) and 38 were conservatively managed. During follow-up, 9 (24%) of 38 patients in the non-operative group presented renal function deterioration and 3 presented with urinary infections and were submitted to pyeloplasty. Of the 39 patients surgically managed, 76% presented improvement of hydronephrosis and 90% showed a non-obstructed pattern on diuretic renography. The differential renal uptake, as measured by DMSA scan, remained stable in the three groups analyzed (conservative, initial pyeloplasty, and delayed pyeloplasty). There was a minimal improvement in those units submitted to pyeloplasty with impaired renal function at baseline (< 40%). Mean renal uptake was 28.6% at admission and 33.9% at the end of follow-up. CONCLUSION: There was a wide spectrum of ureteropelvic junction stenosis. Surgical intervention in a subgroup of patients with severe hydronephrosis and impaired function may possibly improve or preserve renal parenchyma. Conversely, conservative management and clinical follow-up are safe and desirable for the subgroup with mild/moderate pelvic dilatation and preserved renal function.

Premature acute myocardial infarction in a child with nephrotic syndrome.

We report a case of acute myocardial infarction in a nephrotic child. A 7-year-old boy with a 4-year history of steroid-unresponsive nephrotic syndrome due to mesangial proliferation disease presented with acute vomiting and chest pain. An electrocardiogram showed ST elevation and pathological Q waves in leads consistent with anterior and septal myocardial infarction. Subsequent cardiac catheterization showed no evidence of atherosclerotic coronary artery disease, and thrombotic occlusion of the anterior descending coronary artery was the likely cause of the event. Myocardial scintigraphy showed extensive myocardial damage. The child had no long history of extreme hypercholesterolemia or hypertriglyceridemia. The case suggests that children with long-lasting nephrotic syndrome may be at increased risk for ischemic cardiovascular events, due to hyperlipidemia as well as a hypercoagulability state. The literature is reviewed regarding the relationship between nephrotic syndrome and the incidence of ischemic heart disease.

Deposição pulmonar de radioaerossol e desempenho clínico verificados com espaçador fabricado no Brasil / Aerosol deposition and clinical performance verified with a spacer device made in Brazil

Objetivo: Verificar a deposição pulmonar e radioaerossol e o desempenho clínico obtidos com um espaçador desenvolvido e produzido no Brasil. Métodos: Procedeu-se à verificação qualitativa num paciente com fibrose cística e semiquantitativa em dois voluntários sadios da deposição pulmonar de 99mtecnécio-fitato por meio do sistema de nebulização Aerogama Medical acoplado ao espaçador e uma gama câmara Siemens, modelo Orbiter, conectada a um microcomputador. Na etapa seguinte, ao espaçador acoplou-se frasco de aerossol de dose medida contendo salbutamol no tratamento de 50 crianças de 4 meses a 13 anos em crise aguda de asma, sendo a resposta terapêutica pós-broncodilatador avaliada de escore clínico. Foram feitas até quatro aplicaçoes consecutivas do medicamento, com intervalo de 20 minutos entre cada uma delas. O escore clínico foi pontuado após cada uma dessas aplicações. Resultados: Na avaliação qualitativa da deposição pulmonar, a silhueta pulmonar obtida após inalação do radioaerossol através do espaçador foi comparável àquela revelada pela cintilografia inalatória convencional, ao passo que 7,5 por cento e 8,0 por cento do radioaerossol depositaram-se em ambos os pulmões dos dois voluntários na análise semiquantativa. Na etapa clínica observou-se significância estatística (p<0.001) quando o escore da admissão foi comparado àqueles verificados aos 20 e 40 minutos após inalação do broncodilator o mesmo não ocorrendo aos 60 e 80 minutos. Conclusões: Embora tenha sido empregada técnica alternativa para o estudo da deposição pulmonar, os achados cintilográficos aproximam-se daqueles obtidos em estudos com outros dispositivos espaçadores, o mesmo ocorrendo com resposta clínica após administração de salbutamol

Increased gastric emptying induced by Helicobacter heilmannii type 1 infection in rats.

The association between Helicobacter pylori infection and gastric motility abnormalities is still controversial, partly because of the lack of an appropriate animal model. H. heilmannii type 1 (Hh1), a spiral bacterium that infects the stomach of both man and pigs, easily colonises and induces an inflammatory response in the gastric mucosa of rodents. For these reasons, the present study investigated the relationship between gastric motility in rats experimentally infected with Hh1 and correlated the results with serum gastrin and gastric somatostatin concentrations, as these hormones seem to be involved in gastric motility. Ten rats were inoculated with gastric mucus from an Hh1-positive pig and 10 animals with gastric mucus from an Hh1-negative pig (control group). After 56 days, gastric emptying was studied in vivo by scintigraphy. The animals were then killed, blood samples were collected for serum gastrin measurement, strips of the gastric wall were obtained for an in-vitro motor study and fragments of the gastric antrum were obtained for somatostatin content evaluation, Hh1 diagnosis and histological study. There was a significant increase in gastric emptying in the test group compared with the controls as demonstrated by the in-vivo and in-vitro studies. Serum gastrin levels were significantly higher and somatostatin levels were lower in the test group than in the controls. In addition, infected animals showed evidence of gastritis on histological examination. Gastric motility is altered in rats infected with Hh1, a fact possibly related to concurrent abnormalities of gastrin and somatostatin secretion.