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.

Pulmonary Oxygen Toxicity in Rats: Changes of Lung Clearance of 99mTc-DTPA and Bronchoalveloar Lavage / 대한마취과학회지

Animal study was performed to determine the changes in rat lung permeability in hyperoxic condition. 3 groups of rats (n=8 each) were exposed to 100% oxygen for 24 hr(group 2), 48 hr(group 3) and 72 hr(group 4), respectively, and compared with control (group 1 at room air, n=8). The time course of development of solute flux was evaluated by the clearance of 99mTc-labeled diethylenetriamine pentaacetate ( 99mTc-DTPA) from the lung, Afterwards, bronchoalveolar lavage (BAL) was performed to measure the concentration of albumin and determine the evidence of cell injury and inflammation in lung. BAL fluids were analyzed to determine several markers of cell injury and inflammation including total and differential cell counts, lactate dehydrogenase (LD), alkaline phosphatase (ALP), extracellular potassium (K+) and globulin (total protein minus albumin). 99mTc-DTPA clearance was significantly increased by exposure for 48 hours of hyperoxia. Albumin concentration ratio (BAL albumin concentration divided by serum albumin concentration) was increased sharply after 48 hr. Significant changes in WBC counts and differential counts were not found until 48 hr of hyperoxia. Elevated LD concentration was observed at 48 hr and thereafter, and ALP, K+, and globulin concentration ratio (BAL globulin /serum globulin) was significantly high only in group 4. Mortality was not observed until 72 hr when 3 of 8 rats were dead. It is concluded that significant 99mTc-DTPA clearance, and cellular and biochemical findings of BAL could not be observed until 48 hr in rats exposed to 100 % oxygen.