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Biomedical subjects

K Huibregtse

Publications and source records attributed to K Huibregtse.

At least 91 records · Page 5Linked to original sources
PubMed1994

Addition of dimethylsulphoxide to methyl-tert-butyl ether and ethyl propionate increases cholesterol dissolving capacity and cholesterol gall stone dissolution in vitro.

There is a discrepancy between in vitro cholesterol dissolving efficacy of methyl-tert-butyl ether (MTBE) and ethyl propionate and cholesterol gall stone dissolution in vivo. This study investigated whether the presence of bile changes the cholesterol dissolving capacity of MTBE and ethyl propionate. The addition of dimethylsulphoxide to MTBE or ethyl propionate was also studied to discover if it improves the dissolving capacity for cholesterol gall stones. The presence of bile caused a 25% decrease in cholesterol dissolving capacity of both MTBE and ethyl propionate (p < 0.0001). This inhibitory effect of bile could be overcome by the addition of dimethyl-sulphoxide: dimethylsulphoxide caused an increase in cholesterol dissolving capacity of MTBE and ethyl propionate, the increase depending on the dimethyl-sulphoxide/bile ratio in the mixture. Mean dissolution time of weight, size, and patient matched cholesterol gall stones was 220 minutes in MTBE and 130 minutes in MTBE/dimethylsulphoxide (p < 0.0001). No stones dissolved completely in ethyl propionate or ethyl propionate/dimethyl-sulphoxide within 300 minutes. In conclusion, MTBE/dimethylsulphoxide is a more potent dissolving agent for cholesterol gall stones than MTBE, giving a 40% reduction in dissolution time. Addition of dimethylsulphoxide to ethyl propionate does not result in faster stone dissolution. MTBE and MTBE/dimethylsulphoxide are far superior to ethyl propionate as solvents for cholesterol gall stones.

Bile↗
PubMed1994

Bile viscosity in patients with biliary drainage. Effect of co-trimoxazole and N-acetylcysteine and role in stent clogging.

BACKGROUND: The main disadvantage of endoscopic insertion of an endoprosthesis is the tendency of the stent to clog after a few months. In this study we determined the role of bile viscosity in stent clogging. METHODS: Sixty patients were stented with 10 Fr 11-cm stents. The stents were electively removed after 2 months, and a bile sample was obtained simultaneously. Bile viscosity was measured with a coaxial rotation viscometer. The influence of treatment with antibiotics and a mucolytic agent on viscosity was assessed in a randomized trial. RESULTS: Bile viscosity correlated significantly with DNA and total protein concentration. After treatment with either N-acetylcysteine or co-trimoxazole a lower mean value of the viscosity was observed, but this was not statistically significant. There was no correlation between bile viscosity and the amount of sludge adhering to the stents. CONCLUSIONS: In most patients bile viscosity plays a limited role in stent clogging. Only in patients with excessively high viscosity do mucolytic agents or treatment with antibiotics seem to have a role.

Acetylcysteine↗
PubMed1993

Benign biliary strictures. Surgery or endoscopy?

OBJECTIVE: This study compared the results of surgery and endoscopy for benign biliary strictures in one institution, over the same period of time and with the same outcome definitions. SUMMARY BACKGROUND DATA: Surgery is considered the treatment of choice, offering more than 80% long-term success. Endoscopic stenting has been reported to yield similar results and might be a useful alternative. METHODS: In this nonrandomized retrospective study, 101 patients with benign biliary strictures were included. Thirty-five patients were treated surgically and 66 by endoscopic stenting. Patient characteristics, initial trauma, previous repairs, and level of obstruction were comparable in both groups. Surgical therapy consisted of constructing a biliary-digestive anastomosis in normal ductal tissue. Endoscopic therapy consisted of placement of endoprostheses, with trimonthly elective exchange for a 1-year period. RESULTS: Mean length of follow-up was 50 +/- 3.8 and 42 +/- 4.2 months for surgery and endoscopy, respectively. Early complications occurred more frequently in the surgically treated group (p < 0.03). Late complications during therapy, occurred only in the endoscopically treated group. In 46 patients, the endoprostheses were eventually removed. Recurrent stricturing occurred in 17% in both surgical and endoscopic patients. CONCLUSIONS: Surgery and endoscopy for benign biliary strictures have similar long-term success rates. Indications for surgery are complete transections, failed previous repairs, and failures of endoscopic therapy. All other patients are candidates for endoscopic stenting as the initial treatment.

Adult↗
PubMed1993

Bile duct injury after laparoscopic cholecystectomy: the value of endoscopic retrograde cholangiopancreatography.

This study describes the value of endoscopic retrograde cholangiopancreatography (ERCP) in patients with bile duct injury after laparoscopic cholecystectomy. Twelve consecutive patients were studied over a one year period. In all patients the biliary tree was visualised during ERCP. Four patients had complete bile duct obstruction, seven patients had a stricture (two with concomitant leakage), and one patient had leakage from a hepatic branch. Three patients with complete obstruction, presented with a relatively prolonged symptom free, 'silent' period before diagnosis. In all four patients with complete transection, a proximal hepaticojejunostomy was performed. In one patient with a tough fibrous stricture, secondary to incorrect clip placement, passage of the guidewire was impossible, leaving surgical reconstruction as the only therapeutic option. All remaining seven patients with leakage or strictures, or both were successfully treated by endoscopic sphincterotomy only (n = 1) or sphincterotomy and subsequent stent placement (n = 6). When patients do not recover uneventfully after laparoscopic cholecystectomy even without cholestasis or jaundice, early ERCP is recommended as a safe and valuable method to detect bile duct injury and to suggest treatment. Subsequently, more than half of such patients can be treated endoscopically. Extended follow up is needed to evaluate the longterm results.

Adult↗
PubMed1993

Plastic or expandable biliary endoprostheses?

Endoscopic biliary drainage with a PVC stent provides excellent palliation for the patient with malignant biliary obstruction. The main disadvantage of this technique is occlusion of the stent after 3-4 months by biliary sludge. This complication is reduced with larger diameter stents, which have led to the development of expandable metal stents. These stents are less susceptible to obstruction by biliary sludge and remain patent longer than the PVC endoprostheses. Their main disadvantage is that tumor ingrowth through the open meshwork eventually leads to stent obstruction. Other relative disadvantages include the high cost of the metal stents and the inability to retrieve them endoscopically or surgically once deployed. Studies have shown that patients with a short life expectancy do not benefit from metal stents over the use of the standard PVC stent. Patients with a longer life expectancy, however, who are not considered surgical candidates, are better palliated with an expandable metal stent. Further development in metal stent technology may lead to improved function and will broaden the indication for its use.

Aged↗
PubMed1992

Evaluation of endoscopy for early detection of gastric-stump cancer.

The value of endoscopic surveillance of postgastrectomy patients for the early detection of gastric-stump cancer is controversial. Using data from an Amsterdam postgastrectomy cohort of 2633 patients, we have done a retrospective analysis of the effect on mortality from gastric cancer of endoscopic surveillance in these patients. Between 1976 and 1982, 504 symptom-free patients from the Amsterdam cohort participated in an endoscopic surveillance programme. All patients were followed up until 1988. Relative to the general Dutch population, risk of death from gastric cancer was less among patients who took part in surveillance than among those who did not participate. However, differences were small and similar differences existed for risk of death from lung and colorectal cancers, suggesting the presence of selection. Our study seems to confirm that large-scale surveillance of postgastrectomy patients is not justified.

Academic Medical Centers↗
PubMed1992

Biliary stent occlusion--a problem solved with self-expanding metal stents? European Wallstent Study Group.

The main limitation in the endoscopic palliation of malignant biliary obstruction is due to stent blockage. One of the factors thought to be of importance is the diameter of the endoprosthesis. In this paper, we report the results of a multicenter European study with a one cm diameter self-expanding metal stent (Wallstent) in 103 patients with malignant biliary obstruction. Insertion of the stent following guidewire positioning was successful in 97.1% of the patients without any cases of de novo cholangitis developing after the endoscopic procedure. The median follow-up for the entire group was 145 days. In all but 3 patients, the stent expanded to more than 80% of its maximum diameter. Two patients had ongoing cholangitis after stent insertion. Long-term complications manifested by late cholangitis, were seen in 18% of the cases after a median interval of 125 days. The occlusion rate by biliary sludge was 5% after a median time period of 175 days which is substantially less than the 21% occlusion rate reported for polyethylene stents. In conclusion, our results show that the Wallstent can be easily placed in distal and mid-CBD strictures after guidewire passage, with most of the patients having a- good drainage effect. The occlusion rate by biliary sludge is significantly less than for conventional polyethylene stents, but the occlusion by tumor ingrowth is substantial. A disadvantage is the high cost of the Wallstent. Further randomized trials will be required to determine the cost-benefit ratio for the use of this stent.

Adult↗
PubMed1992

Early recurrence of obstructive jaundice after placement of a self-expanding metal endoprosthesis.

Self-expanding metal endoprostheses have ben used in the treatment of malignant obstructive jaundice for a few years. We report on a patient with obstructive jaundice due to a metastasis of a squamous cell lung cancer into the pancreatic head who received an expandable metal endoprosthesis and suffered recurrent jaundice and cholangitis after 38 days. On repeat ERCP, a very narrow stenosis was seen in the stent lumen caused by tumor ingrowth through the mesh. Intraluminal biopsies showed squamous cell carcinoma. A 10 Fr plastic endoprosthesis was inserted through the self-expanding stent with good drainage. On the basis of this experience, we feel that when faced with a patient with obstructive jaundice due to metastatic disease from a rapidly progressive carcinoma, the use of the currently available self-expanding metal endoprosthesis should be discouraged until the results of prospective studies with large numbers of patients have proven its superiority over the plastic endoprostheses. Meanwhile, modifications to prevent tumor ingrowth through the mesh of the stent are under investigation.

Carcinoma, Squamous Cell↗
PubMed1992

Postoperative bile leakage: endoscopic management.

Bile leakage is an infrequent but serious complication after biliary tract surgery. This non-randomised single centre study evaluated the endoscopic management of this problem in 55 consecutive cases. Treatment consisted of standard sphincterotomy and, if needed, subsequent stone extraction with or without endoprosthesis placement. The aim of all treatments was to facilitate bile flow into the duodenum. The biliary tract and the site of the leakage were visualised during endoscopic retrograde cholangiopancreatography (ERCP) in 98%. There was distal obstruction in 33--caused by retained gall stones in 15 patients and concomitant strictures in 18. Overall, 48 of 55 patients were treated endoscopically. An excellent outcome (clinical and radiological resolution of the bile leak) was achieved in 43 patients (90%). Five patients (10%) had continuing sepsis from which they died. Postoperative bile leakage can be diagnosed safely and effectively by ERCP and subsequent endoscopic management is successful in most cases.

Adult↗
PubMed1992

Biliary stenting: cosmetic or clinical value?

Since the initial description of endoscopic placement of transpapillary stents, this technique has gained wide acceptance in the management of pancreatico-biliary diseases. We now know by and large what can be achieved and what the complications are. Studies comparing endoscopic and surgical treatment in pancreatic cancer patients show an initial advantage of the endoscopic method, which is partly counterbalanced by the late complications of stent blockage. Clinical studies are necessary to define better the subgroups of patients that benefit most from the various treatment modalities. Further improvement is necessary to solve the problem of late stent occlusion.

Aged↗
PubMed1992

Benign fibrosing disease at the hepatic confluence mimicking Klatskin tumors.

BACKGROUND: Hilar obstructions remain a challenge with regard to diagnosis and treatment. METHODS: In the period from 1984 to 1990, 82 patients underwent resective surgery under the presumptive diagnosis of hilar cholangiocarcinoma (Klatskin tumor). The diagnosis was based on the combined appearances on direct cholangiography and ultrasonography in all cases, with the use of various other imaging modalities in some cases. RESULTS: The perioperative findings from an experienced surgical team were usually thought to be compatible with bile duct carcinoma. However, histologic examination of the resected specimens revealed benign fibrosing or localized sclerosing lesions in 11 patients (13.4%). CONCLUSIONS: The current state of diagnostic imaging fails as yet to discriminate reliably between benign and malignant hilar lesions. Whereas the immediate therapeutic consequences may be equal (resection followed by hepaticojejunostomy), the late consequences differ in a major way because benign disease has a much better prognosis. In the presence of suspicious hilar obstruction, operable lesions should not be treated by "palliative" intubational techniques and radiation therapy without a firm diagnosis of malignancy. However, overtreatment (extended liver resection, vascular reconstruction, and liver transplantation) should be avoided as well when a benign lesion has not been ruled out.

Adenoma, Bile Duct↗