Investigation and treatment of renal calculi associated with hypercalciuria

Thirty-four patients presenting to a urology clinic over a five-year period with renal calculi and either hypercalciuria or hypercalcemia were investigated by measurements of serum parathyroid hormone and urinary calcium and cAMP. Ten patients were hypercalcemic and were found to have primary hyperparathyroidism. Of the remaining patients all but one had excessive urine calcium excretion after an oral calcium load. In addition, 9 patients were shown to have elevated fasting urinary calcium levels while on a low-calcium diet, raising the possibility of impaired renal calcium conservation as one factor causing their hypercalciuria. The measurement of urinary cAMP levels did not contribute to the accuracy of diagnosis and did not permit further subclassification into different types of hypercalciuria. There was a decrease in urinary calcium excretion and a marked reduction in stone-related events in 10 patients with severe renal stone disease during treatment with hypocalciuric agents.

Long-term results of dialysis therapy with a highly permeable membrane

A five-year study of short-term dialysis using highly permeable polyacrylonitrile membrane AN 69 was started in March 1973 to compare the effects of AN 69 and Cuprophan membrane (CM). The time of dialysis was calculated for each patient on the basis of vitamin B12 clearance of the dialyzer and the residual glomerular filtration rate. For the study, 101 patients (38,555 dialysis sessions) who had been dialyzed for more than six months were selected. They were divided into three groups: Group I (n = 31) patients treated with AN 69 only; Group II (n = 31) patients treated with CM; Group III (n = 39) patients treated first with the CM and then with AN 69. Patients treated with AN 69 had higher levels of plasma urea but no particular metabolic disturbances were observed. The dialysis sessions were significantly better tolerated with AN 69 than with CM, however, the main advantage of using AN 69 is the shortening of dialysis time. The duration of dialysis was 9.5 +/- 0.2 hours per week with AN 69 and 16.4 +/- 0.2 hours per week with CM. Shortening of dialysis time permits better social rehabilitation of the patients. The shorter dialysis was not associated with any recognizable side effects that could be demonstrated by routine clinical and biological analysis.

Is selective therapy of recurrent nephrolithiasis possible?

We evaluated, in 128 patients with recurrent nephrolithiasis, the efficacy of special treatment programs for some of the common causes of nephrolithiasis, chosen on the basis of their ability to correct underlying physicochemical and physiologic derangements. Therapy included sodium cellulose phosphate for 18 patients with absorptive hypercalciuria, thiazide diuretics for 27 patients with absorptive hypercalciuria and for 10 with renal hypercalciuria, orthophosphate for eight patients with hypophosphatemic absorptive hypercalciuria, allopurinol for 21 patients with hyperuricosuric calcium oxalate nephrolithiasis, thiazide and allopurinol for 26 patients with absorptive hypercalciuria with hyperuricosuria, and high fluid intake and/or low calcium diet for 22 patients with normocalciuric nephrolithiasis. Patients in all seven groups had a significant reduction in stone formation during 1.70 to 3.37 years of treatment, as compared with the pretreatment period of three years. Remission was found in 70 to 91 percent of patients and reduced stone formation rate was encountered in 88 to 100 percent. Each treatment program produced a significant decline in stone formation rate from 1.90 to 2.28 stones per year to 0.09 to 0.55 stones per year. The actual number of stones formed during treatment was significantly lower than the number predicted from the pretreatment frequency of stone formation (less than 26 percent). The results provide evidence supporting a selective approach to therapy of nephrolithiasis.

Recent advances in dietary fiber and colorectal diseases

Dietary fiber has emerged in the past decade as a factor in nutrition that appears to have complex physiological and clinical implications. A great deal of research has focused on its effect on colorectal diseases. Some human epidemiological studies on colon cancer point to a possible preventive role of dietary fiber, but the results are confounded by the difference in the intake of many other food substances such as fat and the overall differences in the dietary pattern of the populations investigated. Animal studies using chemical carcinogens, such as 1,2-dimethylhydrazine, have lent support to a protective role of certain components of fiber, such as purified cellulose. Other fiber polymers, such as pectin, have not shown any protective effect. Perhaps the strongest evidence for a protective role of fiber in the colon comes from studies relating low dietary fiber intake to the higher incidence of diverticular disease of the colon; addition of dietary fiber to the diet of patients with symptomatic diverticular disease seems to relieve pain effectively. Recently, some preliminary studies have shown the possible correlation of low dietary fiber intake with a greater incidence of ulcerative colitis and Crohn's disease, but these studies are too limited in number and scope to allow any conclusion to be reached at this time.

Decreased urinary glucose excretion and plasma cholesterol level in non-insulin dependent diabetic patients with guar

The effect of guar gum in lowering urinary glucose excretion and plasma cholesterol was studied in ten sulphonylurea-treated non-insulin dependent diabetic patients during a four week treatment period. The 24-hour urinary glucose excretion fell gradually and increased again to pretreatment value after withdrawal of guar. The glucose output dropped by 33 and 51% in the 3rd and 4th week of the guar treatment period (p less than 0.01) compared to the mean of the pre-plus postguar level. The plasma cholesterol concentration also fell significantly during treatment with guar (p less than 0.01).

Guar gum is not a panacea in diabetes management

Guar gum was incorporated into the diets of six insulin dependent diabetics drawn from one general practice. Amounts between 6 and 59.6 g daily were used for four to six weeks and compared with a previous two week control period. Unlike some other studies, little improvement was obtained in diabetic control and a small reduction in cholesterol levels occurred. The guar was well tolerated in amounts below 30 g a day.

Are fibre supplements really necessary in diverticular disease of the colon? A controlled clinical trial

Fifty-eight patients with uncomplicated diverticular disease of the colon took bran crispbread, ispaghula drink, and placebo for four months each in a randomised, cross-over, double-blind controlled trial. Assessments were made subjectively, using a monthly self-administered questionnaire, and objectively, by examining a seven-day stool collection at the end of each treatment period. In terms of a pain score, lower bowel symptom score (the pain score and sensation of incomplete emptying, straining, stool consistency, flatus, and aperients taken), and total symptom score (belching, nausea, vomiting, dyspepsia, and abdominal distension) fibre supplementation conferred no benefit. Symptoms of constipation, however, when assessed alone, were significantly relieved. Both fibre regimens produced the expected changes in stool weight, consistency, and frequency. It is concluded that dietary fibre supplements in the commonly used doses do no more than relieve constipation. Perhaps the impression that fibre helps diverticular disease is simply a manifestation of Western civilisation's obsession with the need for regular frequent defecation.

Unrefined carbohydrate and dietary fibre in treatment of diabetes mellitus

Sixteen diabetics were studied over six-week periods on two diets--a conventional carbohydrate-restricted diet and a diet which excluded all refined (fibre-depleted) carbohydrate but which allowed unrefined (fibre-intact) carbohydrate freely. On the latter, there was a substantial increase in dietary fibre intake. Despite this, there was no change in 24-h urinary excretion of glucose nor in blood glycosylated haemoglobin concentration, and there was only a modest improvement in post-prandial plasma glucose concentration. We suggest that simply switching from refined to unrefined cereal foods without increasing total carbohydrate intake is unlikely to produce much improvement in diabetic control.