Patients with rheumatic effusion consistently showed a high level of pleural SC5b-9, in contrast to those with malignant effusions, and this is compatible with the results of a previous study that showed that SC5b-9 was >2.0 mg/L in two patients with rheumatic effusion and in none with malignant pleural effusion. They also showed that SC5b-9 was >2.0 mg/L in all patients with tuberculotic pleural effusion, but we could not confirm this finding. In the present study, although the mean level of SC5b-9 was significantly higher in patients with tuberculosis than with malignancy, less than half of 23 tuberculous patients had levels over 2 AU/mL (mean, 9.88 AU/mL; median, 0.78 AU/mL; range, 0.1 to 100 AU/mL). Hara et al concluded that SC5b-9 could be used to differentiate between tuberculous and malignant pleurisy, but since they had only two patients with rheumatoid arthritis, its use to differentiate rheumatic from tuberculous pleural fluid was not estimated. Our results clearly show that higher SC5b-9 values are observed in patients with rheumatoid arthritis than in patients with tuberculous pleurisy.
In tuberculous pleural effusions, high concentrations of C3d, Bb, and SC5b-9 and their positive correlation to each other, but a normal level of C4 and its activation products, confirm alternative pathway activation more canadian pharmacy levitra. We measured relative low values of C4d and SC5b-9 in tuberculotic pleural effusion compared with the previous studies. In the study of Hara et al, they had 26 patients with tuberculous pleural effusion diagnosed by the demonstration of mycobacteria in the effusion or biopsy specimen microscopically and/or by culture or typical histology in the biopsy specimen, while in the present study, we had 23 patients with tuberculous pleural effusion diagnosed either by culture in the pleural fluid or sputum by histology or when clinically suspected and positive response for tuberculous chemotherapy is received. We thought that the relatively large group of 11 patients with clinical diagnosis only in the present study could explain this difference. Therefore, we divided our patients into three groups on the basis of the method of diagnosis, and noted that those patients whose diagnosis was based on histology without bacterial proof had the lowest mean SC5b-9 (mean, 0.77; range, 0.53 to 1.26), whereas it was higher in patients with positive culture (mean, 16.8; range, 0.24 to 100) or with clinical diagnosis only (mean, 9.61; range, 0.1 to 100). In C4d levels, there was no difference between the groups. The difference between our results and previous ones is unlikely to be due to patient selection.