Water-Loading Test in Bacteriuria

Excretion of bacteria in the urine was measured during administration of a large water load over a two-hour period to 26 elderly subjects. Five patients had morning bacteriuria with more than 105 colonies per milliliter. Bacterial concentration and excretion rates increased during water loading in these patients and reached a peak at 60 to 100 minutes. In eight subjects excretion of bacteria was increased during diuresis. In 13 subjects with negligible base-line bacteriuria the urine became or remained negative. Renal function was impaired in both groups with frank and transient bacteriuria. The identical time course of the bacterial rise during diuresis in subjects with frank and occult bacteriuria and their similar impairment of renal function implies an upper rather than a lower urinary-tract origin of bacteriuria. The water-loading test may be useful for screening subjects with doubtful bacteriuria. © 1972, Massachusetts Medical Society. All rights reserved

Renal effects of a new anabolic steroid (29'038-Ba) in old age

The renal effects of 29'038-Ba, a new long-acting injectable anabolic steroid, have been studied in a group of fifteen elderly subjects with normal or impaired renal function. Renal clearances of inulin and endogenous creatinine, the estimated renal blood flow, and the TmPAH were increased by 16.8, 17.2, 17.9 and 35.3 percent respectively after administration of a total of 400 mg of this compound, in contrast to non-significant changes of CPAH and maximal concentrating capacity. No disturbances of liver function were observed in any of the subjects studied. No general side-effects were noticed except for transiently increased libido, reported by three female subjects in the middle of the treatment-period. © 1968 Springer-Verlag

Mechanisms of renal tubular defects in old age

The mechanisms of renal tubular dysfunction in old age have been examined in twenty-eight clinically healthy elderly subjects without infection, and in fourteen subjects of similar age with laboratory evidence of intrarenal infection. The data were compared with those from thirteen clinically healthy young subjects. Studied were: proximal tubular (TmPAH) and distal tubular (CH20) activity, minimal and maximal osmolal U/P ratios, maximal osmolal excretion in hydropenia, and GFR levels under standard hydration and under water-loading. The reduction of GFR in old age is evident particularly in men under conditions of standard hydration: it is accentuated in the presence of renal infection. Proximal tubular activity is also significantly lower in elderly men, especially if they have chronic bacteriuria. The reduction is closely related to GFR levels, with identical Tm PAH: Cin ratios in all groups. This supports the intact nephron hypothesis for this part of the nephron. Distal tubular activity is depressed in old age in both sexes proportionately more than proximal tubular activity or the GFR. The lower CH20: GFR ratios imply a selective distal tubular damage. Maximal osmolal U/P ratios in hydropenia are significantly higher in the young (mean 3.67) than in either the elderly non-infected (mean 2-79) or the elderly infected subjects (mean 2'12). Conversely, minimal U/P ratios in water-loading are lower in the young (mean 0.247) than in either elderly group (means 0-418 and 0-668). Osmolal excretion in hydropenia is not different between the groups, but urine flows in water-loading clearly separate them. The data indicate that simple functions of the distal-collecting tubule (e.g. the CH20), are less affected in old age than are functions involving several medullary structures (as is the maximal Uosm or U/P ratio). They suggest that the main impairment of the distal tubular cell involves the failure to achieve a proper osmotic gradient between tubular fluid and blood, rather than an inability to excrete or re-absorb an adequate amount of solute. Finally, it appears that renal infection aggravates the larger glomerular and proximal tubular deficits observed in non-infected men: it depresses distal tubular function equally in both sexes

Mass detection of bacteriuria by combination of two screening tests

The Uriglox screening test was compared with the modified Griess Nitrite test and with standard urine cultures in the detection of significant bacteriuria on 400 ambulant and asymptomatic residents of the Athens Home for the Aged. The modified Nitrite test alone detected 62 %, and the Uriglox test 79 of the 103 cases with positive urine cultures in the examined group. There was significant overlap in the positive cases picked up by each screening test separately, the Uriglox test identifying more Klebsiella infections. Since there were no false-positive cases with either one of the employed tests, the cases identified by one or the other or both screening tests amounted to 95% of the total number of bacteriuric samples. The combination of the moderately sensitive but highly specific test of Nitrite, with the very sensitive test of Uriglox, can effectively substitute for the expensive and timeconsuming quantitative bacterial counts with pourplate techniques in mass screening for bacteriuria

Dietary saturated and trans fatty acids and cholesterol and 25-year mortality from coronary heart disease: the seven countries study.

Background. In the Seven Countries Study associations between intake of individual fatty acids and dietary cholesterol were studied in relation to serum cholesterol and 25-year mortality from coronary heart disease. All analyses concern only intercohort comparisons. Methods. In the baseline surveys carried out between 1958 and 1964, risk factors for coronary heart disease were measured among 12,763 middle-aged men constituting 16 cohorts in seven countries. In 1987 and 1988 equivalent food composites representing the average food intake of each cohort at baseline were collected locally and analyzed in a central laboratory. The vital status of all participants was verified at regular intervals during 25 years of follow-up. Results. Of the individual saturated fatty acids, the average population intake of lauric and myristic acid was most strongly related to the average serum cholesterol level (r > 0.8, P 0.8, P < 0.001); the trans fatty acid elaidic acid (r = 0.78, P < 0.001); and dietary cholesterol (r = 0.55, P < 0.05). Conclusions. Interpreted in the light of experimental and clinical studies, the results of these cross-cultural analyses suggest that dietary saturated and trans fatty acids and dietary cholesterol are important determinants of differences in population rates of coronary heart disease death