Pulmonary involvement in Behcet's disease:: evaluation of 123I-MIBG retention

Pulmonary involvement in Behcet's disease (BD) is reported to indicate poor prognosis and high mortality. Our aim was to evaluate the pulmonary vascular status in BID. As I-123-meta-iodobenzylguanidine (I-123- MlBG) shares the same uptake, storage and release mechanisms as norepinephrine, associated with the functional state of pulmonary endothelium, it may reflect endothelial injury. Twenty-five patients (13 males, 12 females; mean age, 36.44 years) and 12 age-matched controls were included. After intravenous injection of I-123-MIBG, thorax images were taken at 15 min and 4 h. Appropriate regions of interest were drawn, and heart to mediastinum. (H/M) ratios and lung retention indices (LRI) were calculated. The difference between the LRI of controls (75.6+/-4%) and patients (87.7+/-10%) was found to be extremely significant (P<0.005). The LRIs of active (92.85+/-12%) and inactive (83.65+/-5%) states of BID were significantly different (P < 0.05) from each other. There was no significant difference between the H / M ratios of controls (2.4 +/- 0.27) and patients (2.39 +/- 0.31) or between patients in active and inactive disease states. Our study revealed prolonged lung retention of I-123-MIBG in BD, probably reflecting the severity of the disease. In conclusion, I-123-MIBG lung retention is a valuable finding in the evaluation of pulmonary vascular status and may be a potential marker of prognosis in BD, ((C) 2001 Lippincott Williams & Wilkins).