Infected mural thrombus caused by Bacteroides fragilis.

findings of Sonnenblick et al of the greatest positional changes in Pa02 that were found with two patients with cardiac failure were because of occult contralateral effusions, even though the diagnosed effusions were reported to be small. Indeed, cardiac failure is most often associated with bilateral effusions if more sensitive diagnostic techniques are performed. 3 The two reported patients with ascites may also have had an occult contralateral effusion. Nearly 30 percent of patients have been found to have bilateral effusions with ascites when demonstrated with radioactive labeled albumin techniques.’ Even though it has recently been reported that sensitive findings on routine roentgenogram such as the thorn sign5 and displacement of a sharp costophrenic angle6 suggest effusions, as much as several hundred milliliters of loculated pleural fluid may remain undetected without the use of other diagnostic testing.7 In conclusion, although the significance of the study by Sonnenblick and associates is noteworthy, it is possible that over half the patients had bilateral effusions, and not unilateral as reported.