[Antibacterial therapy in surgery of the inner and middle ear. A study of co-trimoxazole penetration into the perilymph (author's transl)].

Studies of the type presented here have rarely been undertaken and should be useful in surgery and pathology of the inner and middle ear. Samples of perilymph were collected during stapedectomy in patients with otosclerosis. In view of the very small volume of perilymph obtainable from each patient's vestibule (2 to 4 microliter), the only assay method that could be used to measure drug levels was thin layer chromatography on silica gel. Despite pooling of the perilymphs of 5 patients, trimethoprim (TMP) levels could not be measured but the authors were able to demonstrate that sulfamethoxazole (SMZ) does penetrate into the perilymph. Since the TMP-SMZ combination (co-trimoxazole) is active against the pathogens usually encountered in middle ear fluids, it is concluded that the drug could be of benefit in the treatment of middle and inner ear infections or after surgical operations on this area.