Abstract: Method for the rapid diagnostic of an infection of the urinary tract (UTI), by a specific examination of urine.The method of analyzing a urine specimen, for the rapid and simultaneous counting of both viable bacteria and leucocytes (white blood cells or WBC), consists of:(1) simultaneous labeling of said bacteria and said white blood cells (WBC) present in said urine specimen, with a fluorescent viability marker of bacteria, said marker tagging and accumulating in both bacteria and white blood cells, under the same conditions and leading to different fluorescent elements;(2) automatically counting all the fluorescent elements by photoelectric detection of the fluorescent marker; and(3) simultaneously classifying said fluorescent elements in fluorescent viable bacteria and in fluorescent white blood cells, in view to obtain in one part the total number of bacteria and on the other part, the total number of white blood cells, on the basis of their size.