Influence of bladder fullness on the detection of urinary tract obstruction by dynamic renal scintigraphy.

OBJECTIVE: To investigate the influence of bladder fullness on the diagnosis of urinary tract obstruction during dynamic renal scintigraphy with a diuretic stimulator. MATERIALS AND METHODS: We studied 82 kidneys in 82 patients submitted to dynamic renal scintigraphy with a diuretic stimulator. We compared the proportional elimination of the radiopharmaceutical 99mTc-DTPA from the kidneys before and after bladder emptying in post-diuretic images, classifying each image as representing an obstructed, indeterminate, or unobstructed kidney. RESULTS: The overall elimination of 99mTc-DTPA from the kidneys was 10.4% greater after bladder emptying than before. When the analysis was performed with a full bladder, we classified 40 kidneys as obstructed, 16 as indeterminate, and 26 as unobstructed. When the 40 kidneys classified as obstructed were analyzed after voiding, 11 were reclassified as indeterminate and 3 were reclassified as unobstructed. Of the 16 kidneys classified as indeterminate on the full-bladder images, 13 were reclassified as unobstructed after voiding. CONCLUSION: In dynamic renal scintigraphy with a diuretic stimulator, it is important to obtain images after voiding, in order to perform a reliable analysis of the proportional excretion of 99mTc-DTPA from the kidneys, avoiding possible false-positive results for urinary tract obstruction.

OBJETIVO: Verificar a influência da repleção vesical no diagnóstico da obstrução do trato urinário durante a cintilografia renal dinâmica com estímulo de diurético. MATERIAIS E MÉTODOS: Foram estudados, retrospectivamente, 82 rins de 82 pacientes submetidos a cintilografia renal dinâmica. Compararam-se as porcentagens de excreção do radiofármaco DTPA-99mTc pelos rins antes e após o esvaziamento vesical nas imagens pós-diurético, classificando-os como obstruídos, indeterminados ou não obstruídos. RESULTADOS: A avaliação da excreção do radiofármaco pelos rins mostrou que houve aumento de 10,4% na taxa de excreção global quando a bexiga foi esvaziada. Dos 82 rins estudados, 40 foram considerados obstruídos, 16 indeterminados e 26 como não obstruídos, na análise com a bexiga repleta. Na análise das imagens após micção, dos 40 classificados como obstruídos, 11 passaram a ser classificados como indeterminados e 3 como não obstruídos. Além disso, dos 16 rins apontados como indeterminados nas imagens com a bexiga repleta, 13 passaram a ser considerados não obstruídos com a bexiga vazia. CONCLUSÃO: É fundamental uma imagem após a micção na cintilografia renal dinâmica para uma análise fidedigna da porcentagem de excreção do radiofármaco pelo rim, evitando-se possíveis falso-positivos para obstrução do trato urinário.

Influence of bladder fullness on the detection of urinary tract obstruction by dynamic renal scintigraphy / Influência da repleção vesical na pesquisa de obstrução do trato urinário utilizando cintilografia renal dinâmica

Abstract Objective: To investigate the influence of bladder fullness on the diagnosis of urinary tract obstruction during dynamic renal scintigraphy with a diuretic stimulator. Materials and methods: We studied 82 kidneys in 82 patients submitted to dynamic renal scintigraphy with a diuretic stimulator. We compared the proportional elimination of the radiopharmaceutical 99mTc-DTPA from the kidneys before and after bladder emptying in post-diuretic images, classifying each image as representing an obstructed, indeterminate, or unobstructed kidney. Results: The overall elimination of 99mTc-DTPA from the kidneys was 10.4% greater after bladder emptying than before. When the analysis was performed with a full bladder, we classified 40 kidneys as obstructed, 16 as indeterminate, and 26 as unobstructed. When the 40 kidneys classified as obstructed were analyzed after voiding, 11 were reclassified as indeterminate and 3 were reclassified as unobstructed. Of the 16 kidneys classified as indeterminate on the full-bladder images, 13 were reclassified as unobstructed after voiding. Conclusion: In dynamic renal scintigraphy with a diuretic stimulator, it is important to obtain images after voiding, in order to perform a reliable analysis of the proportional excretion of 99mTc-DTPA from the kidneys, avoiding possible false-positive results for urinary tract obstruction.

Resumo Objetivo: Verificar a influência da repleção vesical no diagnóstico da obstrução do trato urinário durante a cintilografia renal dinâmica com estímulo de diurético. Materiais e métodos: Foram estudados, retrospectivamente, 82 rins de 82 pacientes submetidos a cintilografia renal dinâmica. Compararam-se as porcentagens de excreção do radiofármaco DTPA-99mTc pelos rins antes e após o esvaziamento vesical nas imagens pós-diurético, classificando-os como obstruídos, indeterminados ou não obstruídos. Resultados: A avaliação da excreção do radiofármaco pelos rins mostrou que houve aumento de 10,4% na taxa de excreção global quando a bexiga foi esvaziada. Dos 82 rins estudados, 40 foram considerados obstruídos, 16 indeterminados e 26 como não obstruídos, na análise com a bexiga repleta. Na análise das imagens após micção, dos 40 classificados como obstruídos, 11 passaram a ser classificados como indeterminados e 3 como não obstruídos. Além disso, dos 16 rins apontados como indeterminados nas imagens com a bexiga repleta, 13 passaram a ser considerados não obstruídos com a bexiga vazia. Conclusão: É fundamental uma imagem após a micção na cintilografia renal dinâmica para uma análise fidedigna da porcentagem de excreção do radiofármaco pelo rim, evitando-se possíveis falso-positivos para obstrução do trato urinário.

Effect of a plant origin drug on the biodistribution of 99mTc-DTPA in Wistar albino rats

In recent years all over the world, medicinal plants are used quite a lot but side effects of biological and chemical contents and radiopharmaceutical interactions for each consumer in question aren't entirely well-known. The studies of plant origin drug interaction with radiopharmaceuticals are highly relevant and desired. One of them is passiflora syrup (Passiflora incarnata L., Passifloraceae) which is widely used for depression, insomnia, anxiety and menopause period. The aim of current study is to evaluate possible effects of passiflora syrup on the biodistribution of 99mTc-DTPA and its blood cells uptake. DTPA was labeled with 99mTc radionuclide. Biodistribution studies were performed on male Wistar albino rats which were treated via oral feeding-gavage-method with either passiflora syrup or 0.9 % NaCl as control group for ten days. Blood samples were obtained by cardiac blood withdrawal from the rats and they were radiolabeled. The biodistribution results showed that the passiflora syrup decreased the uptake of 99mTc-DTPA in kidneys and in blood cells. 99mTc-DTPA being used widely as a kidney diagnostic agent in nuclear medicine seems to be interacting with orally taken passiflora. Passiflora syrup may modify the uptake of 99mTc-DTPA by kidney. The knowledge of this negative effect may contribute to reduce the risk of misdiagnosis and/or repetition of the examinations in nuclear medicine.

Alveolus-capillary permeability on both normal and HIV seroreactive individuals

The aim of this study was to evaluate the alveolus-capillary permeability by the lung clearance rate of 99mTc-DTPA(Technetium99m-diethylene triamine penta-acetate), (LCR-DTPA), both in normal and in asymptomatic HIV seroreactive patients. Thirty individuals were studied, 21 seronegative normal volunteers and 9 HIV seroreactive patients presenting normal chest radiography and no respiratory infection symptoms. LCR-DTPA was determined by inhaling 99mTc-DTPA and obtaining images in a gamma camera. The 99mTc-DTPA clearance rate in normal individuals was 0.99±0.15 percent.min-1 and in patients 2.31±1.25 percent.min-1. There was a significant statistical difference between the two groups (p< 0.05). Two patients who presented LCR-DTPA higher than 4.3 percent.min-1 presented pneumocystis pneumonia one month later. Seroreactive AIDS patients, previously asymptomatic that presented pneumonia later showed higher LCR-DTPA than the seroreactive who did not develop the illness. These results suggested that LCR-DTPA could be a predictive method for the clinical development of pneumocystis pneumonia in asymptomatic HIV seroreactive patients.

A integridade funcional da barreira alvéolo-capilar pode ser alterada por diversas condições patológicas e por outros fatores como a irritação do epitélio alveolar, provocada pelo fumo etc, levando a um aumento da permeabilidade alvéolo-capilar. O objetivo deste trabalho foi verificar a permeabilidade do epitélio pulmonar através da determinação da taxa de depuração pulmonar do aerossol de 99mTc-DTPA (LCR-DTPA) em indivíduos normais e em pacientes assintomáticos HIV sororreativos. Foram estudados 30 indivíduos, sendo 21 voluntários normais e 9 HIV sororreativos sem sintomas de infecção oportunista, com radiografias de tórax normais ou sem sinais sugestivos de infecção pulmonar. A LCR-DTPA foi determinada após inalação de 99mTc-DTPA sob a forma de aerossóis e contagem externa da radiação, em função do tempo, em gama câmara. A LCR-DTPA dos controles foi de 0.99±0.15 por cento.min-1 e nos pacientes sororreativos,de 2.31±1.15 por cento.min-1 houve diferença significativa entre os dois grupos (p< 0.05). Dois pacientes tiveram LCR-DTPA acima de 4,3 por cento.min-1, estes desenvolveram um mês após o exame. Observou-se que os pacientes sororreativos por Imunodeficiência Adquirida (SIDA), sem sintomas específicos para pneumocistose que posteriormente desenvolveram a doença, a LCR-DTPA foi significativamente maior que a dos outros HIV pneumocistose clínica sororreativos que não desenvolveram a doença (p<0.01). Estes resultados sugerem que a LCR-DTPA pode ser um método preditivo do desenvolvimento clínico da pneumocistose, não invasivo, de fácil realização e cômodo, para o paciente HIV sororreativo assintomático.

Schistosomiasis haematobia in Brazilian patients: clinical and renal functional evaluation with 99mTc-DTPA

The present study was carried out at the Army Central Hospital, Rio de Janeiro, Brazil, from September 2000 to December 2001, employing diethylenetriamine penta-acetic acid labeled with technetium-99m (99mTc-DTPA) to evaluate the renal function of nineteen symptomatic patients infected with S. haematobium during a peace mission in Mozambique. Results evidenced that the most frequent clinical manifestations were hematuria (68.4%) and low back pain (68.4%) and 73.7% patients had altered dynamic renal scintigraphy expressed by an increase in the excretory phase independently of the symptoms duration; furthermore, none of them had mechanical obstructive pattern. Schistosoma haematobium glomerulopathy could be considered a pathological finding without correlation with the disease clinical manifestations.

Schistosomiasis haematobia in Brazilian patients: clinical and renal functional evaluation with 99mTc-DTPA

The present study was carried out at the Army Central Hospital, Rio de Janeiro, Brazil, from September 2000 to December 2001, employing diethylenetriamine penta-acetic acid labeled with technetium-99m (99mTc-DTPA) to evaluate the renal function of nineteen symptomatic patients infected with S. haematobium during a peace mission in Mozambique. Results evidenced that the most frequent clinical manifestations were hematuria (68.4 percent) and low back pain (68.4 percent) and 73.7 percent patients had altered dynamic renal scintigraphy expressed by an increase in the excretory phase independently of the symptoms duration; furthermore, none of them had mechanical obstructive pattern. Schistosoma haematobium glomerulopathy could be considered a pathological finding without correlation with the disease clinical manifestations.(AU)