Bacteriuria in pregnancy treated with a single dose of cephalexin.

Of 87 women in whom bacteriuria was diagnosed on dip slides at between 9 and 22 weeks gestation only 51 (59%) had true bacteriuria in urine obtained by suprapubic aspiration. A single oral dose of cephalexin (3 g) was given to 37 of these patients, 10 were Indian and none of them had recurrence of infection after treatment, whereas 11 of the 27 (41%) 'indigenous' women again had bacteriuria within 2 weeks of treatment. None of the other 26 patients had recurrent bacteriuria in the pregnancy studied. Success of treatment was not related to renal concentrating ability nor, apart from ethnic group, were there other significant differences between successes and failures. Although single-dose treatment seems to be less effective in pregnancy than in the non-pregnant patients, it is an acceptable method of treatment provided that all treated patients are followed closely to detect those who do not respond and require further therapy.