The relationship of alveolar permeability and pulmonary inflammation in patients with systemic lupus erythematosus.

The alveolar epithelium permeability (AP) in 34 patients with systemic lupus erythematosus (SLE) was measured by Tc-99m DTPA radioaerosol inhalation lung scintigraphy. The degree of AP damage in SLE was represented as the slope of the time-activity curve from the dynamic lung imagings. The patients were divided into two subgroups according to the following two criteria. [A] clinical feature: they were separated as stable or flare stage; and [B] chest X-ray findings: they were separated as positive or negative results. Meanwhile, the quantitative Gallium-67 (Ga) lung scan was performed as Ga uptake index (GUI) to evaluate the severity of inflammation in the lungs in SLE. The results show that [1] there were no significant statistical differences in the degree of AP damage between the two subgroups according to clinical features or chest X-ray findings, and [2] no good correlation between the degree of AP damage and inflammation of the lungs was found. In conclusion, the change of AP in SLE may be a mechanism not related to the presentation of clinical features or chest X-ray findings, and the degree of AP damage in SLE is not related to the severity of pulmonary inflammation.