Dissolution of Gallstones with Simvastatin, an HMG CoA Reductase Inhibitor

The aim of this study was to determine whether12 months of therapy with Simvastatin, an HMG CoAreductase inhibitor, would dissolve gallstones.Twenty-seven subjects entered the study, all had afasting oral cholecystogram, ultrasound examination,and fasting serum lipids prior to therapy. In addition,22 subjects had their gallbladder ejection fraction,after CCK, determined by radionucleotide scanning. Eleven subjects had the cholesterol saturationindex (CSI) of bile calculated before and at the end of12 months of therapy. Of the 27 subjects, 26 completed12 months of treatment with Simvastatin 20 mg daily. There was a significant fall in thetotal serum cholesterol (27%, P < 0.0001), LDLcholesterol (31%, P < 0.0001), triglyceride (34%, P< 0.0001) but no change in HDL after 12 months oftherapy. Simvastatin treatment resulted in a 28% fall in the CSI ofbile at the end of therapy (P < 0.01). Theconcentrations of individual bile acids did not changewith therapy, and apart from a slight but significantincrease in arachidonate, there were no othersignificant changes in the fatty acid composition of thebiliary phospholipids. After 12 months of Simvastatintherapy there was a small decrease in the gallstonediameter but complete dissolution of gallstones was notachieved in any subjects. In conclusion 12 months oftherapy with Simvastatin was effective in lowering theserum lipids and the CSI of bile but was not effective in dissolving gallstones.     

AN INTEGRATED HAEMATURIA CLINIC

The prognosis of bladder cancer is worsened by delay in its management. To reduce such delay we have organised a clinic where intravenous urography and cystoscopy, using a flexible cystoscope, are carried out at the patient's first visit. In a two-year period 321 patients attended this clinic. The results of investigation in 305 patients are reported. A total of 6% of patients with microscopic haematuria (n = 52) and 15% of patients with macroscopic haematuria (n = 253) had transitional cell carcinomata. This difference was not significant (P=0.08, chi-squared). The delay between referral and trans-urethral resection of tumour for patients with bladder tumours was reduced from a mean of 60 days to a mean of 33 days by the institution of the clinic (P<0.01, Mann-Whitney). We recommend that all patients referred to a urological service with haematuria, whether macroscopic or microscopic, should be investigated. The integration of that investigation in a single day decreases delays in diagnosis and management.     

Retroperitoneal fibrosis associated with malignant disease

The clinical features of 19 patients with malignant infiltration of the retroperitoneal tissues are described. These patients usually presented with unexplained uraemia and nonspecific symptoms; only a few had other evidence of malignancy. The diagnosis was resolved only by histological examination of multiple biopsy specimens. Since the prognosis is usually very poor it is essential to distinguish this condition from non-malignant causes of retroperitoneal fibrosis.     

Insulin precipitation in artificial infusion devices

Summary Precipitation of insulin is a problem with mechanical insulin infusion devices. Therefore conditions affecting insulin precipitation have been studied in a recirculating system using a peristaltic pump. Acetate buffer favoured precipitation and a pH of 2, 3 or 8 resulted in no less (and often more) precipitation than a pH of 7 using either acetate or phosphate buffer. However, no precipitation occurred in a phosphate buffered neutral preparation after ten days of pumping through tubing pretreated with EDTA. In comparison at pH 7, using acetate buffer with untreated tubing, more than 95% of insulin was precipitated in ten days. A heavy metal-insulin association appears to be a major factor in the precipitation. However, some formation of insulin fibrils is probable as the precipitate is autocatalytic and partially acid insoluble. Phosphate buffered highly purified porcine insulin is suitable for relatively prolonged infusion if metal ion contamination of the delivery system is minimised.