Erythromycin in the treatment of non-gonococcal urethritis.

Erythromycin was first used by the author in the treatment of non-gonococcal urethritis in 1954. Using relatively small doses of 100 mg. four times a day for 6 days in 25 male cases the re-treatment rate within 3 months was 33 3 per cent. of those followed (Willcox, 1954). A further series was then undertaken using 300 mg. four times a day for 5 days (Willcox, 1955a, 1955b), which was finally extended to 101 cases when the failure rate proved to be 27 1 per cent. among the 85 patients followed (Willcox, 1955c). Although these results were similar to those obtained with a combination of a single injection of 1 g. streptomycin together with a course of a sulphonamide, they were not as good as those achieved by the tetracyclines which in the past decade have proved the most successful of the antibiotics used in the therapy of this condition. Further interest in erythromycin has arisen from more recent developments in mycoplasma research, particularly regarding the so-called T. strain which Shepard (1960) found in approximately 70 per cent. of cases of non-gonococcal urethritis, a figure later confirmed by other workers (Csonka, Williams, and Corse, 1966). Although the claims for the T. strain as a probable cause of the condition still remain, they are not entirely conclusive, as these mycoplasmata have been found to be present in 12-6 per cent. of healthy adults (Csonka and others, 1966) and in a higher proportion in some random samples taken from special groups of female patients in whose husbands there was no particular suspicion of nongonococcal urethritis. Moreover other causes of non-gonococcal urethritis also have their champions, as for example, the TRIC virus (Dunlop, Harper, Al Hussaini, Garland, Treharne, Wright, and Jones, 1966), while a diphtheroid bacillus has also been recovered (Furness and Csonka, 1966). The observation by Shepard, Lunceford, and Baker (1966) that the T. strain of mycoplasma is