Dopamine DRD4 receptor polymorphism and attention deficit hyperactivity disorder

A polymorphism in the dopamine receptor 4 gene (DRD4) has been related to novelty seeking, Tourette's syndrome, and attention deficit hyperactivity disorder (ADHD). The variability is in a 48-bp repeat in exon 3 of the gene (a transmembrane region). This study examined the relation of the 7-repeat (i.e., high-risk) allele to questionnaire-based diagnoses of ADHD (both combined type and inattentive type). Several positive findings were obtained for ADHD-inattentive type. In an association test, the 7-repeat allele occurred more frequently in children with ADHD-inattentive type than in control children. In genetically discordant sibling pairs, the sibling with a greater number of 7-repeat alleles displayed more inattentive symptoms than his/her co-sibling with fewer 7-repeat alleles. For ADHD-combined type, the 7-repeat allele frequency was greater than that in the control sample. However, a quantitative transmission disequilibrium test yielded no significant linkage of the 7-repeat allele with hyperactive-impulsive symptoms. A categorical TDT yielded no significant findings, but the number of transmissions was small, especially for ADHD-inattentive type.

Hypertensive pancreatic sphincter

Major papilla pancreatic sphincter dysfunction, a variant of sphincter of Oddi dysfunction, causes pancreatitis or pancreatic-type pain. Endoscopic manometry as performed at endoscopic retrograde cholangiography is the most commonly used method to identify sphincter dysfunction. Noninvasive testing, such as secretin-stimulated ultrasound analysis of duct diameter, is less reliable and of relatively low sensitivity. Two-thirds of patients with sphincter of Oddi dysfunction have elevated pancreatic basal sphincter pressure. Patients with suspected or documented sphincter of Oddi dysfunction may respond to biliary sphincterotomy alone, but warrant evaluation of their pancreatic sphincter if symptoms persist after therapy. Whether such pancreatic and biliary sphincters should be treated at the first treatment session is controversial. Pancreatic sphincterotomy is associated with a complication rate very similar to that of biliary sphincterotomy except that the pancreatitis rate is two- to fourfold higher. Prophylactic pancreatic stenting diminishes such pancreatitis by approximately 50%.

Percutaneous radiologic, surgical endoscopic, and percutaneous endoscopic gastrostomy/gastrojejunostomy: comparative study and cost analysis

PURPOSE

To compare the results and costs of three different means of achieving direct percutaneous gastroenteric access.

METHODS

Three groups of patients received the following procedures: fluoroscopically guided percutaneous gastrostomy/gastrojejunostomy (FPG, n = 42); percutaneous endoscopic gastrostomy/gastrojejunostomy (PEG, n = 45); and surgical endoscopic gastrostomy/gastrojejunostomy (SEG, n = 34). Retrospective review of the medical records was performed to evaluate indications for the procedure, procedure technical success, and outcome. Estimated costs were compared for each of the three procedures, using a combination of charges and materials costs.

RESULTS

Technical success was greater for FPG and SEG (100% each) than for PEG (84%, p = 0.008 vs FPG and p = 0.02 vs SEG). All patients (n = 7) who failed PEG subsequently underwent successful FPG. Success in placing a gastrojejunostomy was 91% for FPG, and estimated at 43% for PEG and 0 for SEG. Complications did not differ in frequency among groups. For gastrostomy, the average cost per successful tube was lowest in the PEG group ($1862, p = 0.02); FPG averaged $1985, and SEG $3694. SEG costs significantly more than FPG or PEG (p = 0.0001). For gastrojejunostomy, FPG averaged $2201, PEG $3158, and SEG $3045.

CONCLUSION

Technical success for gastrostomy is higher for FPG and SEG than PEG. Though PEG is the least costly procedure, the difference is modest compared with FPG. For gastrojejunostomy, FPG offers the highest technical success rate and lowest cost. Due to high costs associated with the operating room, SEG should be reserved for those patients undergoing a concurrent surgical procedure.

Increased selective biliary cannulation rates in the setting of periampullary diverticula: main pancreatic duct stent placement followed by pre-cut biliary sphincterotomy

BACKGROUND

Selective biliary cannulation is often difficult when there is a periampullary diverticulum, especially when the papilla is within the diverticulum. We report eight such cases in which a new technique was used to achieve biliary access.

METHODS

Among 4138 ERCPs, there were 246 cases (5.9%) with periampullary diverticula. Biliary cannulation initially failed in eight patients (3.3%), five of whom had previously undergone six failed attempts at other institutions. A technique was used whereby the papilla was kept out of the diverticulum by placement of a pancreatic duct stent. Needle-knife sphincterotomy was then performed followed by attempts to achieve biliary access.

RESULTS

Biliary entry was immediately successful in five patients and successful at a second ERCP in two (overall success 87.5%). Two patients developed post-ERCP pancreatitis.

CONCLUSIONS

When the papilla is within the periampullary diverticulum, placement of a main pancreatic duct stent keeps the papilla out of the diverticulum, thereby facilitating pre-cut needle-knife sphincterotomy and selective biliary cannulation.

Stabilization of vasoactive intestinal peptide by lipids

An anionic phospholipid, phosphatidylglycerol (PG), induced vasoactive intestinal peptide (VIP) to adopt a helical conformation, determined by circular dichroism studies. PG inhibited the trypsin-catalyzed, antibody-catalyzed and uncatalyzed cleavage of VIP, measured by radiometric and HPLC methods. Phosphatidylcholine, a neutral lipid, did not alter the circular dichroism spectra of VIP, and it was without detectable effect on the rates of VIP cleavage. Trypsin-catalyzed cleavage of Boc-Ile-Glu-Arg-methylcoumarinamide, a substrate unrelated in sequence to VIP, proceeded at equivalent rates in the absence and presence of PG, which suggests that the phospholipid did not exert a nonspecific inhibitory effect on the enzyme. Study of the kinetics of antibody-catalyzed VIP cleavage indicated that the inhibition by PG was due to decreased affinity for VIP, suggested by observations of increased K(m) values and unaltered Vmax values. Incorporation of VIP in the liposomes and the liposomal surface permitted maintenance of the peptide in essentially undegraded form at 37 degrees C for 8 days. The longevity of liposomal VIP administered i.v. to mice was increased by about 5-fold compared with aqueous VIP. These observations indicate that certain phospholipids and liposomes can be applied to circumvent the rapid loss of VIP in vitro and in vivo due to degradative processes.

Correlations between vascular calcification and atherosclerosis: a comparative electron beam CT study of the coronary and carotid arteries

PURPOSE

Electron beam CT (EBCT)-derived coronary artery calcium scores correlate with the extent of atherosclerosis, but there is a substantial variance about the general relationship between coronary calcification and coronary atherosclerosis. The relationship between calcification and atherosclerosis may also differ in various arteries. This study was designed to evaluate whether the relation between carotid artery intima-media thickness (IMT) and carotid artery calcium could be used as a correction factor to improve the correlation between coronary calcification and coronary atherosclerosis.

METHOD

We measured atherosclerosis in the coronary and carotid arteries by angiography and ultrasonography, respectively, and quantified coronary and carotid calcium deposition with EBCT in 50 subjects. The correlation between the findings in the carotid and coronary arteries was investigated.

RESULTS

Coronary artery calcium score correlated with coronary angiography and with carotid calcium score. Coronary stenosis correlated with carotid IMT. There was no meaningful correlation of carotid IMT and carotid calcium.

CONCLUSION

There is an intraindividual variation in the relationship of plaque mass to calcification among different vessels. The relation between carotid artery calcification and carotid IMT is not predictive of the relation between coronary artery calcification and coronary obstruction.

Endoscopic sphincterotomy for stones by experts is safe, even in younger patients with normal ducts

OBJECTIVE

To provide current information on the risks of endoscopic sphincterotomy for stone.

SUMMARY BACKGROUND DATA

In recent years (since the popularity of laparoscopic cholecystectomy), endoscopic sphincterotomy has been used increasingly for the management of bile duct stones in relatively young and healthy patients. The validity of this trend has been questioned using data on short-term complications derived from earlier decades that involved more elderly and high-risk patients.

METHODS

Seven academic centers collected data prospectively using a common database. Complications within 30 days of the procedures were documented by standard criteria.

RESULTS

Of 1921 patients, 112 (5.8%) developed complications; two thirds of these events were graded as mild (<3 days in hospital). There was no evidence of increased risk in younger patients or in those with smaller bile ducts. There was only one severe complication and there were no fatalities in 238 patients age <60, with bile duct diameters of <9 mm.

CONCLUSION

Sphincterotomy for stones can be performed very safely by experienced endoscopists.

ERCP and biliary endoscopic sphincterotomy-induced pancreatitis

The magnitude of post-ERCP pancreatitis as a clinical and economic problem has increased, and with it the need to find ways of decreasing its incidence and severity. Furthermore, the study of post-ERCP pancreatitis is interesting as a unique model for acute pancreatitis in general. Current thinking and results of recent promising studies are reviewed.

Endoscopic measurement of pancreatic blood flow

A reduction of pancreatic blood flow has been observed in acute and chronic pancreatitis in animal models. Most available blood flow techniques are either too invasive or impractical to carry out in humans. Since the arrival of endoscopic retrograde cholangiopancreatography (ERCP), our understanding and management of pancreatic disorders has gradually improved. It may now be utilized to investigate what is believed to be a very important factor in the pathogenesis of pancreatic disease and symptoms: pancreatic tissue perfusion.

Endoscopic pancreatic sphincterotomy: techniques and complications

Endoscopic pancreatic sphincterotomy of the major and minor papilla has expanded our approach to the management of a variety of pancreatic disorders. Analysis of the complication rates of this therapy is difficult, however, because a variety of techniques are often used in conjunction with the pancreatic sphincterotomy. This article reviews the techniques and complications of endoscopic pancreatic sphincterotomy. Based on the currently available data, it appears that the complication rates of pancreatic sphincterotomy are probably higher than those of biliary sphincterotomy. Should application of this technique become more widespread, methods to reduce the incidence of post-procedure pancreatitis will demand further investigation.

Diagnosis and therapy of pancreas divisum

Pancreas divisum patients make up a small but problematic portion of ERCP cases. Minor papilla cannulation techniques have been improved. Recurrent pancreatitis patients generally benefit from minor papilla therapy. Methods to select patients who are likely to respond to invasive therapy need refinement. Clinicians and endoscopists are strongly encouraged to be cautious and conservative with this patient group until stronger data indicate optimal management schemes.

Endoscopic therapy of pancreatic disease

Endoscopic management of a variety of benign and malignant biliary tract diseases is now a well-established alternative to surgery. Similar techniques are now applied to the pancreas and are being used in the setting of acute pancreatitis, chronic pancreatitis, complications of pancreatitis, and pancreas divisum. This review analyzes the current state of the art of these exciting applications of endoscopy. Selection of appropriate candidates for the various treatment modalities appears important for optimal results of therapy. However, definite recommendations are difficult to make because there are limited controlled studies, follow-up in most series is brief, and there are no comparison studies of endoscopic versus surgical therapy. At present, careful case selection and conservatism are the appropriate general rule in these therapeutic endeavors. Further prospective random studies are awaited.

Mucin-hypersecreting intraductal neoplasms of the pancreas: a precursor to cystic pancreatic malignancies

BACKGROUND

Muncin-hypersecreting intraductal pancreatic neoplasms were first described in 1982 and have been observed in increasing numbers since. They are observed primarily by endoscopic retrograde cholangiopancreatography (ERCP) and are characterized by an intraductal papillary neoplasm that secretes thick mucin, causing pancreatic duct dilatation and obstructive pancreatitis.

METHODS

Twenty patients are presented, 14 male and six female, with an average age of 59 +/- 11 years. All patients presented with abdominal pain, and most had nausea and vomiting, weight loss, and documented pancreatitis. Of the preoperative studies, ERCP was positive in all patients. Computed tomography scan, endoscopic ultrasonogram, and cytologic findings were less sensitive. Tumor markers were only positive in one patient. All 20 patients were treated surgically. Nine underwent Whipple procedure, one patient had a total pancreatectomy, and nine had distal pancreatic resections. The first patient in the series did not have a pancreatic resection, and his disease evolved into a lethal cystadenocarcinoma causing his death 99 months later.

RESULTS

Histopathologic findings were interpreted as borderline malignant in 17 of the 20 patients, and three patients had evidence of invasive adenocarcinoma. Two of these three patients had nodal or distant metastases at the time of diagnosis, and all three died of adenocarcinoma. Seventeen of the patients are alive and well, although two of three with positive pancreatic margins have had recurrent symptoms and have been successfully reresected.

CONCLUSIONS

The mucin-producing intraductal papillary tumor of the pancreas is a newly described variant of pancreatic cancer. It presents with symptoms of pancreatitis and has a progressive but more indolent course than the more lethal invasive ductal cancers. Patients with unexplained pancreatitis should undergo ERCP investigation, and aggressive surgical therapy should be carried out because the prognosis for this lesion, when appropriately treated, is more favorable than the usual pancreatic cancer.

Evaluation of post-ERCP pancreatitis: potential causes noted during controlled study of differing contrast media. Midwest Pancreaticobiliary Study Group

BACKGROUND

Possible sources of post-ERCP pancreatitis were evaluated during a prospective, randomized, controlled study comparing different contrast media.

METHODS

A total of 1979 patients were randomized and subdivided into groups during the study. Patients were grouped for comparison depending on the type of procedure performed during ERCP. Diagnostic patients studied with pancreatograms (Group I) were compared with other groups, specifically, those not studied with pancreatograms (Group IV). All patients had subjective and objective estimates of the difficulty in cannulation of both ducts. The incidence of postprocedural pancreatitis was compared between and within each group.

RESULTS

In Group I there was a progressively higher incidence of pancreatitis with increased numbers of pancreatic duct injections. Patients with the highest (19.5%) frequency of pancreatitis received 10 or more injections into the pancreatic duct. Group I cases with difficult common bile duct cannulations had a higher frequency of post-ERCP pancreatitis (9.5%), as compared with the entire group (5.6%).

CONCLUSIONS

There was a higher incidence of pancreatitis associated with increased manipulation around the papillary orifice, especially with multiple pancreatic duct injections. There was also a slightly higher incidence of post-ERCP pancreatitis in cases with difficult common bile duct cannulation. Endoscopists are encouraged to evaluate and develop safer cannulation techniques that minimize the number of injections into the pancreatic duct and enhance selective cannulation.

Local thrombolytic therapy as part of a multidisciplinary approach to acute axillosubclavian vein thrombosis (Paget-Schroetter syndrome)

PURPOSE

To evaluate the efficacy of thrombolytic therapy in the treatment of acute axillosubclavian vein thrombosis in patients with Paget-Schroetter syndrome.

MATERIALS AND METHODS

A 4.5-year, retrospective study of all patients with "effort" thrombosis of the axillosubclavian vein was performed.

RESULTS

Six men and eight women (age range, 18-56 years; mean, 34 years) presented with acute axillosubclavian vein thrombosis. Twenty thrombotic events occurred in the 14 patients and were treated with urokinase only (14 of 20) or urokinase combined with percutaneous transluminal angioplasty (PTA) (six of 20), Nine of the 14 treatments with urokinase only (64%) resulted in complete lysis of thrombus, whereas four treatments (29%) resulted in restoration of flow with some residual stenosis, yielding an immediate patency rate of 93%. Eight of the 14 patients remained asymptomatic after thrombolytic therapy (urokinase or urokinase and PTA) alone (n = 4), or in combination with a first rib resection (n = 4) at a mean follow-up of 24 months (range, 1-36 months).

CONCLUSIONS

Thrombolytic therapy appears to be a safe and efficacious method of establishing immediate patency of the axillosubclavian vein and may be helpful in establishing a symptom-free result in patients with Paget-Schroetter syndrome. Rib resection and repeated thrombolytic therapy are frequently necessary to complete treatment.

Radial scanning and linear array endosonography for staging pancreatic cancer: a prospective randomized comparison

BACKGROUND

Endoscopic ultrasound (EUS) is known to be accurate for staging pancreatic cancer. Little data exist to determine if linear array or radial scanning EUS is superior for staging pancreatic cancer. This prospective comparison was undertaken to assess the accuracy of linear array and radial scanning EUS for staging pancreatic cancer.

METHODS

Patients with pancreatic cancer referred for EUS staging were randomized to linear array or radial scanning EUS. Staging accuracy for each was determined by comparison to surgical pathology in those patients going to surgery.

RESULTS

Seventy-nine patients with pancreatic cancer were enrolled and 33 had surgical resection. Of these, 17 patients were randomized to linear array and 16 to radial scanning EUS. The remaining 46 patients did not have surgery because of comorbid illness or clinically unresectable disease. EUS staging accuracy for linear array was 94% (16 of 17) for T and 71% (12 of 17) for N staging, whereas radial scanning was 88% (14 of 16) for T and 75% (12 of 16) for N staging. For predicting vascular invasion, radial scanning was 100% accurate (16 of 16) while linear array was 94% (16 of 17) accurate. There was one false-negative assessment of invasion using linear array EUS.

CONCLUSION

Overall, both EUS designs appear equivalent for staging pancreatic cancer and assessing vascular invasion. In view of our findings and the capability for ultrasound-directed fine-needle aspiration with linear array EUS, this instrument may be the preferred choice for evaluating pancreatic masses.

Presentation of choledochal cysts without intrabiliary communication on endoscopic retrograde cholangiopancreatography

Choledochal cysts have generally been described to communicate with the biliary system. We recently saw three adult patients in whom we could not demonstrate biliary communication between the cyst and the biliary tree, despite a carefully performed endoscopic cholangiopancreatography (ERCP). These cases may represent a variant of type II choledochal cysts. During the 5-year period of review of ERCP records, 30 choledochal cysts were diagnosed, of which 3 (10%) were the noncommunicating cases described in this report.

Complications of endoscopic biliary sphincterotomy

BACKGROUND

Endoscopic sphincterotomy is commonly used to remove bile-duct stones and to treat other problems. We prospectively investigated risk factors for complications of this procedure and their outcomes.

METHODS

We studied complications that occurred within 30 days of endoscopic biliary sphincterotomy in consecutive patients treated at 17 institutions in the United States and Canada from 1992 through 1994.

RESULTS

Of 2347 patients, 229 (9.8 percent) had a complication, including pancreatitis in 127 (5.4 percent) and hemorrhage in 48 (2.0 Percent). There were 55 deaths from all causes within 30 days; death was directly or indirectly related to the procedure in 10 cases. Of five significant risk factors for complications identified in a multivariate analysis, two were characteristics of the patients (suspected dysfunction of the sphincter of Oddi as an indication for the procedure and the presence of cirrhosis) and three were related to the endoscopic technique (difficulty in cannulating the bile duct achievement of access to the bile duct by "precut" sphincterotomy, and use of a combined percutaneous-endoscopic procedure). The overall risk of complications was not related to the patient's age, the number of coexisting illnesses, or the diameter of the bile duct. The rate of complications was highest when the indication for the procedure was suspected dysfunction of the sphincter of Oddi (21.7 percent) and lowest when the indication was removal of bile-duct stones within 30 days of laparoscopic cholecystectomy (4.9 percent). As compared with those who performed fewer procedures, endoscopists who performed more than one sphincterotomy per week had lower rates of all complications (8.4 percent vs. 11.1 percent, P=0.03) and severe complications (0.9 percent vs. 2.3 percent, P=0.01).

CONCLUSIONS

The rate of complications after endoscopic biliary sphincterotomy can vary widely in different circumstances and is primarily related to the indication for the procedure and to endoscopic technique, rather than to the age or general medical condition of the patients.