Sexual behaviour of hemodialyzed patients.

18 married men on home dialysis and 10 of their wives were interviewed (structured interview) to evaluate sexual adjustment. The frequency of intercourse prior to the onset of their disease was reported to be 3.4/week by the patients and 2.4/week by their wives. During maintenance hemodialysis, frequency was reported to be 1.7/week by the patients and 1.0/week by their wives. If libido prior to the disease was rated 100%, the patients reported their libido at the time of the interview as 66+/-34%; only 5 rated their libido as less than 50% of their libido prior to the onset of their disease. After the start of dialysis, considerable time was required before a stable state of sexual activity was reached (13.9+/-7.4 months), presumably reflecting the time required for adaptation to the procedure, loss of anxiety and restoration of physical well-being. Except in older patients, there was good agreement between the feeling of physical fitness as reported by the patients and sexual performance as reported by both the patient and his spouse.

Intramural hematoma of the esophagus: a complication of carbon tetrachloride intoxication with acute renal failure.

Following a period of prolonged severe vomiting, an intramural esophageal hematoma could be demonstrated by endoscopy and by X-ray in a 21 year old patient with hepatic and renal failure after exposure to carbon tetrachloride. The hematoma resolved spontaneously. The intramural hematoma is thought to have developed from a microdissection of the esophageal wall in the presence of a hemorrhagic diathesis.

Unchanged hormone sensitivity of rat fat cell adenylate cyclase in uremia.

The sensitivity to hormones of the fat cell adenylate cyclase system was tested in uremic rats and in pair-fed control animals. Basal enzyme activities averaged 1.25 nmoles of cAMP formed per mg protein per 15 min in controls compared to 1.30 nmoles cAMP/mg protein/15 min in fat cell ghosts obtained from uremic rats. NaF caused an approximately 4-fold stimulation of enzyme activities in both systems. It was shown that parathyroid hormone should be included amongst the hormones which act as stimulators of the enzyme system. The responsiveness of the rat fat cell adenylate cyclase system towards saturating concentrations of ACTH, glucagon, epinephrine and parathyroid hormone was not altered in the presence of chronic renal failure.

[New aspects of calcium metabolism in kidney calculus disease]. / Neue Aspekte des Kalzium-Stoffwechsels bei Nierensteinerkrankung.

Recurrent calcium stone disease appears to be related to a high dietary intake of animal protein. The following mechanisms have been discussed to explain the relationship between dietary protein and calciuria: increased glomerular filtration rate (GFR), increased rate of sulphate excretion, acidosis-induced increase in ionised serum calcium ("filtered load") and decrease in tubular reabsorption, and mobilisation of bone mineral. Protein also diminishes urinary citrate. However, it has not been established in controlled trials whether a reduced dietary intake of protein diminishes the recurrence rate of renal stones. Determination of the normal range of urinary calcium is dependent on numerous variables: size; GFR; age; excretion of Na, Mg and Pi; dietary intake of Ca and protein; season. Ideally, all these variables should be evaluated. In many patients with recurrent stone formation hypercalciuria will be found. There is a consensus of opinion that intestinal Ca absorption is increased, but elevated frequency of a renal Ca leak has not been established. For patient management discrimination between absorptive and resorptive hypercalciuria is important; a simple test that can be performed as an outpatient procedure is proposed in order to make this distinction.

[Hypertension following renal transplantation (author's transl)]. / Hochdruck nach Nierentransplantation.

Hypertension is more frequent in transplant recipients than in the general population. The two most frequent causes are reduced function of the transplant and the presence of the recipient's own kidneys. Beyond the immediate postoperative period, administration of glucocorticoids appears to have little influence on blood pressure. The various forms of arterial stenosis of the transplant are infrequent, but clinically important, because they are susceptible to surgical correction or arterial dilatation. The pathogenetic mechanisms and diagnostic problems of the various forms of posttransplant-hypertension are discussed in this review.

Isotachophoretic determination of urinary citrate in native urine.

The technique of isotachophoresis has been used to develop a specific and sensitive method for the determination of citrate in unprocessed urine. The specificity of the isotachophoretic method was assessed using citrate lyase which caused disappearance of the isotachophoretic citrate signal. The isotachophoretic method compared favourably with the enzymatic method (citrate lyase) for urinary citrate. The normal range for urinary citrate in 25 healthy individuals, as found by isotachophoresis, was 0.33-2.89 mmol/24 h with a mean of 2.1 mmol/24 h.

Sulfur-containing amino acids are a major determinant of urinary calcium.

Epidemiological evidence suggests a relation between dietary protein intake and nephrolithiasis. In addition, generation of acid equivalents from dietary protein increases urinary calcium excretion. To further evaluate the usefulness of epidemiological or clinical tools to study the relation between dietary protein and urinary calcium, the correlation between urinary urea and sulfate excretion on the one hand and calcium excretion on the other hand was examined in 42 healthy individuals. Only a modest correlation was found between urea and calcium excretion (r = 0.33); in contrast, the correlation between sulfate and calcium excretion was marked (r = 0.73) and highly significant (p less than 0.01). It remained significant when the influences of urea, sodium, hydroxyproline, and oxalate excretion were taken into account using partial regression analysis. In 9 healthy male probands, addition of 6 g L-methionine (40 mmol) to their usual diet caused an increase of urinary sulfate (+ 3,795 mg/24 h) and urinary calcium (+ 86.4 mg/24 h). The variable methionine/cysteine-cystine content of dietary proteins may explain why urinary calcium is correlated better with urinary sulfate than urinary urea.

Diabetic nephropathy--are there differences between type I and type II?

It has commonly been assumed that the renal risk in type II diabetes is markedly lower than in type I diabetes since only approximately 5% of the former but 40% of the latter experience renal failure. Based on our observations in the diabetes outpatient department of the University of Heidelberg, we conclude that the cumulative risk of developing proteinuria for the nonproteinuric type II diabetic and the cumulative risk of developing renal failure for the proteinuric type II diabetic are comparable with the respective risks of the type I diabetic. This observation is noteworthy since there is no uncontroversial evidence of hyperfiltration in early type II diabetes. Type II diabetes may be an interesting model for testing the hyperfiltration theory.

The effect of 1,25 (OH)2D3 on bone mineralization: ultrastructural studies in patients with renal osteodystrophy.

The acute effects (15-50 days) of 1,25(OH)2D3 (0.5-2 microgram/day) on the histological, fluorescence-microscopical and ultrastructural appearance of mineralizing osteoid in iliac crest spongiosa were studied in 6 uremic patients on maintenance hemodialysis. While there was a marked decrease on endosteal fibrosis and osteoclast counts, volumetric and surface densities of osteoid continued to stay elevated during the observation period. The number of osteoid seams with tetracycline double label increased in 4/6 patients but no such seams appeared in 2 patients who had shown only nonlabeled seams with diffuse staining of osteoid prior to therapy. In studies with transmission electron microscopy, the interface between non-mineralized osteoid and mineralized bone was irregularly outlined and broad. In contrast to normals, coarse mineral deposits were widely scattered in the nonmineralized osteoid. The mineral deposits had two different appearances, presumable depending on the plane of section relative to the direction of collagen fiber bundles: patches of microcristalline deposits encircling perpendicularly cut non-mineralized collagen bundles and needle- or plate-shaped crystals following the striation pattern of collagen fibers. The findings point to close interaction between the pattern of mineral deposition and collagen texture. The latter was highly irregular (woven) in all uremic patients. Mineral deposits were in part normal and in part highly abnormal in texture, the latter particularly in sites with irregular collagen texture. Upon therapy, no consistent change of the ultrastructure of the mineralizing osteoid/bone interface was observed by transmission or scanning and electron microscopy.

Isotachophoresis for the determination of oxalate in unprocessed urine.

The principle of isotachophoresis has been used to develop a simple, specific and sensitive analytical procedure for the determination of oxalate in unprocessed urine. Analytical conditions were optimized. The accuracy and precision of the method were estimated. The specificity was checked with oxalate decarboxylase. Separation of oxalate from a number of organic acids was achieved. The influence of factors such as storage, calcium concentration, pH or ionic strength was examined. The 24-h urine excretion rates for healthy children, healthy adults and for patients with idiopathic stone formation were established. Lower absolute excretion rates were found in children and females. Urinary oxalate/creatinine ratios were higher in children than in adults. The mean oxalate excretion in 24-h urines of adult healthy individuals was 413 +/- 150 mumol per 24 h per 1.73 m2 (range 195-732). The mean oxalate/creatinine ratio was 0.033 +/- 0.011 (range 0.018-0.065).

[Does the care of diabetic patients with renal failure in the predialysis phase need improvement?]. / Ist die Betreuung niereninsuffizienter Diabetiker in der prädialytischen Phase verbesserungsbedürftig?

The cardiovascular risk profile was assessed in all 208 diabetics accepted for dialysis in 28 German dialysis centres from 1985-1987 (104 men, 104 women, mean age 60 [22-82] years). 71 patients had type 1 and 128 type 2 diabetes, and 9 maturity onset diabetes of the young. Of 169 patients, 164 (97%) had hypertension (median systolic blood pressure at start of dialysis 200 [120-280] mm Hg). Only 74 patients (44%) were on continuing anti-hypertensive medication. Median serum cholesterol was 225 (66-424) mg/dl, LDL-cholesterol 158 (43-335) mg/dl and HDL-cholesterol 32 (10-67) mg/dl. In patients with a history of myocardial infarction (n = 26) the median cholesterol concentration was 269 (126-424) mg/dl, while in those with no history of myocardial infarction (n = 132) it was 221 (66-280) mg/dl (P less than 0.05). Only 5% of the patients had received lipid lowering therapy. Out of 175 patients, 65 (37%) had a history of smoking, and 25 (14%) were still smokers at the start of dialysis. There was a strong association between smoking history and amputations. Only 98 of 208 patients (47%) had had a specialist ophthalmological examination in the 12 months preceding the start of dialysis. Proliferative retinopathy was present in 33 out of 53 (62%) type 1 and 15 out of 98 (15%) type 2 diabetics. Out of 22 patients with unilateral or bilateral blindness, 2 (10%) had received no photocoagulation. - This investigation reveals a need for better medical care of diabetics with pre-end-stage renal failure.

Human fat cell adenylate cyclase. Modulation of parathyroid hormone action by guanine nucleotides.

The effects of guanine nucleotides on basal and parathyroid hormone-stimulated adenylate cyclase of human fat cell ghosts were studied. GTP (10(-7)-10(-3) M) caused a dose-dependent inhibition of basal enzyme activity, but it had no significant effect on PTH-stimulated rates of cAMP-formation. The guanine nucleotide analogue 5'-guanylyl-imidodiphosphate GMP (PNP) when applied in the same concentration range, stimulated basal as well as PTH-activated adenylate cyclase activity up to 300%. GMP (PNP) activation was non-linear with time. PTH-activated the human fat cell adenylate cyclase via an individual receptor distinct from beta-adrenergic receptor sites.

Is there a renal phosphorus leak in recurrent renal stone formers with absorptive hypercalciuria?

In ten male hypophosphataemic hypercalciuric recurrent renal stone formers with absorptive hypercalciuria and ten male normophosphataemic normocalciuric control persons, fasting plasma and urine chemistry was studied throughout the day under basal conditions and following an oral phosphorus load. After overnight fasting, plasma phosphorus and TMP/GFR were lower and urinary calcium higher in patients than in controls. Both in patients and controls, plasma phosphorus rose throughout the morning hours. In the afternoon, plasma phosphorus was almost equal in patients and controls. The circadian rise of plasma phosphorus despite no increase of urinary phosphorus argues against the presence of a fixed renal tubular phosphorus leak in absorptive hypercalciuria, at least in the fasting state. Patients differed from controls not only with respect to urinary calcium, but also with respect to fasting absolute and fractional urinary excretion of sodium and chloride. Increased fractional urinary sodium was found both in normotensive and hypertensive patients. Since tubular reabsorption of phosphorus and the setting of fasting plasma phosphorus depend, among other factors, on tubular handling of sodium, the finding may be relevant for the genesis of transient fasting hypophosphataemia in absorptive hypercalciuria.

Survival and predictors of death in dialysed diabetic patients.

The objective of this study was to examine diabetic patients at the time of admission to maintenance haemodialysis and to follow them for 36 months in order to define predictors of cardiovascular and non-cardiovascular death. This prospective study comprised all consecutive diabetic patients admitted to 28 German dialysis centres between January 1985 and October 1987; 196 patients were examined, 67 Type 1 (insulin-dependent) diabetic (43 male, 24 female; median age 49 years, range 22-73) and 129 Type 2 (non-insulin-dependent) diabetic patients (54 male, 75 female; 64 years, range 37-82). Outcome measures were death, i.e. myocardial infarction, sudden death, cardiac death of other causes, stroke and non-cardiovascular death. Actuarial survival 36 months after the beginning of dialysis was similar in Type 1 (40%) and Type 2 diabetic patients (43%) despite the age difference. Causes of death were myocardial infarction (18%), sudden death (18%), other cardiac causes (18%); stroke (6%); septicaemia (17%) mostly originating from diabetic foot problems; and interruption of therapy. Survival rates and the proportion dying from cardiac causes were similar in patients with diabetic nephropathy or with other primary chronic renal disease and coincidental diabetes. On dialysis, de novo amaurosis or de novo amputation was not observed in any patient. The strongest predictor of myocardial infarction or sudden death was serum lipids on admission. Duration of hypertension, blood pressure at the time of admission to dialysis, left ventricular hypertrophy or end-diastolic diameter by echocardiography, Sokolow index and average predialysis blood pressure, smoking, interdialytic weight gain and type of dialysis were not predictive of cardiovascular death or death by all causes.(ABSTRACT TRUNCATED AT 250 WORDS)

Possible role of inorganic sulphate in the pathogenesis of hyperparathyroidism in chronic renal failure.

In order to investigate the role of hypersulphataemia in the development of hyperparathyroidism the blood levels of inorganic sulphate (SO4(2-)) and phosphate (HPO4(2-)) were compared with total and ionised calcium (Ca) and parathyroid hormone (PTH) in 20 patients with chronic renal failure (CRF). There was a positive correlation between plasma SO4(2-) and serum creatinine. Ionised Ca was inversely correlated with HPO4(2-), SO4(2-) and PTH, respectively. The best correlation was found between ionised Ca and the ion product of HPO4(2-) and SO4(2-). It is suggested that hypersulphataemia might be involved in the pathogenesis of secondary hyperparathyroidism and osteodystrophy in CRF by complex formation with Ca, thereby aggravating the effect of HPO4(2-) on ionised Ca and the resulting PTH stimulation.