A POPULATION STUDY ON RENAL AND URINARY TRACT DISEASES

Abstract

Abstract. Urine specimens have been examined for urinary deposits by the conventional clinical method, that is, by centrifugation and counting of formed elements per high power field (HPF). The criteria for pyuria were at least 5, 11 and 21 WBC/HPF. Conventional urine specimens, without instructions as to midstream collection, showed pyuria by the said criteria in an average of 8.4%, 4.2% and 1.3%, respectively, of the men and 40.3%, 21.0% and 8.8% of the women. The screening comprised 1255 persons, 47.7% being men and 52.3% women. The clean‐voided midstream technique was applied at the screening of 2 643 persons, 50.1% men and 49.9% women. Pyuria was noted in 3.2%, 1.6% and 0.5%, respectively, of the men and in 17.2%, 10.0% and 3.7% of the women. Thus, the midstream technique reduced the incidence of pyuria according to all three criteria by about 60% both in men and in women. In the literature this technique is generally stated to be necessary only in women in order to avoid admixture of formed elements from the urethra and the external genitals. Screening and subsequent medical examination of clean‐voided midstream specimens revealed pyuria in altogether one‐third of the cases on both occasions, at screening alone, or at medical examination alone. White cell casts and clumps of leucocytes occurred in only a few cases. By the criteria of at least 3, 7 and 11 RBC/HPF, the prevalence of haematuria in the first mentioned series was 4.8%, 1.5% and 0.2%, respectively, for the men and 10.2%, 3.0% and 1.3% for the women; in the latter series (midstream specimens) the comparable figures were 3.9%, 1.0% and 0.6% for the men and 5.7%, 2.3% and 1.4% for the women. While the midstream technique reduced the prevalence of haematuria by about 45% for the women, using the criteria of 3 RBC/HPF, the other figures agreed fairly well for the two series; reservations are made for a relatively small number of observations in some instances. Labstix gave in too many cases false negative results for haematuria. Screening and/or subsequent medical examination revealed haematuria in only about one‐sixth of the cases on both occasions, in about one‐third at medical examination alone, and in the rest on screening alone. Proteinuria was also present in 10–15% of the specimens with pyuria. Significant bacteriuria was recorded in 13% of the specimens with slight pyuria, in 30% of those with marked pyuria, and in 4% of those without pyuria. There seemed to be no correlation between the presence of pyuria and that of significant bacteriuria. L‐forms were demonstrated in only 0.5% and various types of Mycoplasma in 30% of the specimens. Tubercle bacilli were found in two cases of pyuria. Every three persons with and every five without pyuria had elevated ESR. Thus, the constellation pyuria—elevated ESR was of limited diagnostic value.