[Serious urinary infections and pregnancy].

Retention of infected urine in the upper urinary tract which is due to obstruction is a serious condition during pregnancy. The authors report their experience on five cases and propose attitudes to adopt against such emergency. Ultrasounds allow accurate diagnosis of the obstruction and may be helpful to find its etiology. Plain X ray film could be of interest mainly for stone recognition after the third month of gestation. Surgical treatment, when possible allows either relief of obstruction and cure of the original disease, otherwise performance of percutaneous nephrostomy represents a better way of drainage until the end of pregnancy.