W. R. Cattell

Excretion Urography: I—Factors Determining the Excretion of Hypaque

Abstract The development of a simple method for the chemical analysis of sodium diatrizoate has permitted the investigation of the factors affecting the renal excretion of 45% Hypaque in normal subjects and in patients undergoing routine IVP. The study has shown that the amount of Hypaque excreted in unit time is a function of the GFR and the plasma concentration at that time. The rate of excretion is maximal in the first 10–20 minutes following the injection of medium and follows the rise and fall in plasma concentration. The ten-minute plasma concentration has been shown to be a function of dose and is readily and accurately reproducible. Studies of the urinary concentration of Hypaque have shown that despite prior claims to the contrary, increasing doses up to 0·75 ml./lb. body weight are associated not only with increasing urine flow but also increased concentration of contrast media in the urine. It has been shown that the concentration of Hypaque in the urine was markedly affected by the state of hy...

Renal function in lithium and non-lithium treated patients with affective disorders.

Renal function was examined in 101 patients maintained on sustained‐release lithium carbonate for periods ranging from 1 to 12.5 years. A control group of patients with affective disorders who had never been given lithium was also investigated as well as a control group of normal subjects of comparable age and sex.

RELATION BETWEEN RESIDUAL URINE VOLUME AND RESPONSE TO TREATMENT OF URINARY INFECTION

Abstract Residual urine volume (R.U.V.) has been measured using 131 I-hippuran in seventy-six women referred with a clinical diagnosis of urinary infection and correlated with the presence of bacteriuria and ease of treatment. Twenty-two of the patients remained abacteriuric for 3 months and of these only three had an increased R.U.V. (>1.0 ml.). The fifty-five women with bacteriuria had significantly increased R.U.V.S. Of the thirty who were easy to treat, sixteen had an increased R.U.V. while of the twenty-four who were difficult to treat all but two had an abnormal R.U.V. Patients over the age of 50 had significantly greater R.U.V.S than younger women, and proportionately more of them were difficult to treat. It is concluded that an increase in R.U.V. is associated with difficulty in treating urinary infection, and that R.U.V.S. of as little as 1–10 ml. are important in this regard.

Excretion Urography: II. The Relation between Hypaque Excretion and the Intravenous Urogram

Abstract Visualisation of the collecting system during intravenous pyelography was assessed by eye and the scores thus obtained were correlated with the plasma concentration and dose of Hypaque 45, the glomerular filtration rate and the patients state of hydration. Patients with impaired renal function were excluded. The mean scores were found to rise with dose up to at least 0·75 ml./lb. In the patients studied, variations in GFR could not be shown to have any effect on the X-ray scores, but their importance in subjects with impaired renal function is emphasised. The scores were higher in patients with low initial rates of urine flow (dehydrated) than in those with high rates of flow (not dehydrated). Overnight dehydration had little effect. No benefit was shown from administering the contrast medium by drip infusion as compared with normal intravenous injection.

Excretion urography in advanced renal failure

Abstract The value of excretion urography has been studied in 48 patients with severe non-oliguric renal failure (blood urea more than 200 mg/100 ml. or creatinine clearance less than 10 ml./minute). The renal outlines were clearly defined in all but four patients. In each of the ten patients with extrarenal obstruction sufficient of the collecting system was seen to diagnose the presence of the obstruction. In only two patients without obstruction was no pyelogram seen. No ill effects were observed. The importance of careful radiography is emphasized. The need for facilities for dialysis is discussed.

Excretion urography in acute renal failure.

High-dose excretion urography has been carried out in 32 patients presenting with non-obstructive acute oliguric or non-oliguric renal failure. An early, dense, persisting nephrogram has been observed in all patients with acute uncomplicated tubular necrosis and in patients with acute oliguric pyelonephritis. This appearance is modified by the presence of pre-existing renal disease. Different patterns have been observed in patients with acute glomerular disease, severe renal ischaemia, and chronic glomerular disease. The study demonstrates that careful analysis of the evolution of the nephrogram in patients with acute renal failure provides valuable information as to the nature of the parenchymal disease.

Comparison of the renal excretion of Hypaque 45% and Urografin 60%

Abstract The renal excretion of Hypaque 45% and Urografin 60% in doses containing equal amounts of diatrizoate was compared ten times in six subjects. The doses ranged from 0·25 to 0·75 ml./lb. Hypaque 45% or the equivalent amount of Urografin 60%. In every study the urinary concentration of diatrizoate was higher after Hypaque 45% (the pure sodium salt) than after Urografin 60% (predominantly the methylglucamine salt). The diuresis was always greater with Urografin 60%. The pattern of excretion of diatrizoate was the same with both compounds.

The effect of DDAVP on intravenous urography

The possible role of an antidiuretic hormone analogue, DDAVP (1 deamino-8-D-arginine vasopressin), in intravenous urography has been studied. The minimum effective dose of intravenous DDAVP in normal hydrated subjects was shown to be 2 ng/kg. During intravenous urography in fluid restricted subjects, a dose of 1 microgram DDAVP was necessary to reduce significantly the urine flow rate after contrast medium injection. Although the mean pyelographic score after DDAVP was increased, the differences observed were not statistically significant. The possible reasons for this finding are discussed.

The effect of osmotic diuresis on urinary iodine concentration using contrast media of differing osmolality

The urinary iodine concentrations of a monomer (sodium iothalamate), a dimer (sodium iocarmate) and a non-ionic compound (metrizamide) have been compared in dogs with varying levels of solute excretion. All the animals were undergoing maximal antidiuresis. In dogs with normal solute excretion, metrizamide and iocarmate produced higher urinary iodine concentrations than iothalamate. There was no significant difference between metrizamide and iocarmate. With increasing levels of solute excretion, the differences between the compounds were reduced. These findings suggest that contrast media of reduced osmolality are unlikely to have a special place in advanced renal failure.

Investigation of adults with haematuria

haemophiliac patients. If this was the case identifymg other factors that are prognostic assumes greater importance. We agree with Dr Cuthbert and colleagues that serum IgA titres tend to rise with disease activity in patients who have already progressed to AIDS. We found, however, that high titres were recorded before symptoms developed and that a serum IgA titre of greater than 4 5 g/l (the upper limit of normal for our laboratory) was an independent predictor for the development ofAIDS in 14 out of 17 of our patients in whom raised titres were recorded (X2=9 19; p<00l). The three year progression rate in seven of these patients who already had raised IgA titres at recruitment was 100% compared with 32% in patients with normal titres at recruitment. Lastly, we and other workers6 have found the presence of p24 antigen to be an important prognostic indicator. We note that p24 antigen was measured in the Edinburgh cohort, though no reference was made to its usefulness or otherwise in predicting disease progression.