Trimethoprim in the treatment of urinary infections in hospital

Abstract

Success in the cure of urinary infections of hospital patients was compared for five-day courses of sulphamethoxazole alone, sulphamethoxazole plus one-tenth its weight of trimethoprim, and sulphamethoxazole plus one-fifth its weight of trimethoprim (Septrin). The cure rates were 65%, 84%, and 92% respectively. Fifty-four per cent. of 111 patients had urinary tract abnormalities. Forty-three per cent. of the causative organisms were sulphonamide-resistant in vitro. There were no major side-effects, though two patients had pruritus or a rash.The degree of potentiation of sulphamethoxazole activity by one-fifth the weight of trimethoprim was so great that its cure rate of infections due to sulphonamide-resistant organisms exceeded that of sulphamethoxazole alone used in infections due to sulphonamide-sensitive organisms. The degree of synergism between trimethoprim and sulphamethoxazole demonstrated in vitro against urinary organisms was directly related to the cure rate of the combination.