The detection of asymptomatic bacteriuria in general practice.

AS LONG ago as 1881, Roberts drew attention to the existence )AI of asymptomatic bacteriuria and postulated that this condition might prove to be a forerunner offrank urinary tract infection. Dodds (1931) suggested that this condition had particular significance in pregnancy, though Baird (1936) whilst agreeing that symptomless urinary infection occurred in pregnancy was unimpressed both by its frequency and its contribution to maternal ill health. Using quantitative bacteriological urinary counts, Kass (1956) showed that it is possible to distinguish between urinary tract infection and contamination in voided specimens of urine. Infected urine contains organisms in a concentration greater than 100,000 per ml., usually consisting of a single species of recognized urinary pathogen. In contrast to this, contaminated specimens of urine have a bacterial count less than 10,000 organisms per ml., often consisting of several species. With the development of this technique various population groups were studied in order to define the extent of the problem, the natural history of bacteriuria and also to determine whether other conditions are associated with the presence of asymptomatic bacteriuria. During these studies it has become apparent that pregnant women are particularly liable to asymptomatic bacteriuria and that this can influence the health of the expectant mother. A number of surveys of bacteriuria of pregnancy, including those of Kass (1960), Kaitz and Hodder (1961), Turner (1961) and Sleigh et al. (1964), reveal an average incidence of about 5 per cent. These bacteriuric women have been shown to be at particular risk of developing frank pyelonephritis, hypertensive disease of pregnancy and, less certainly, premature delivery. Frank pyelonephritis develops in 40 per cent of bacteriuric women in pregnancy and Kincaid-Smith (1965) regards this as being sufficient reason for detecting and treating bacteriuria. Indeed, Le Blanc and McGanity (1964) and Little (1965) have shown that pyeloneph-