Biomedical subjects

Margaret Marcon

Publications and source records attributed to Margaret Marcon.

3 recordsLinked to original sources

PubMed2006

Biliary atresia with choledochal cyst: implications for classification.

BACKGROUND & AIMS: To illustrate the limitations of the embryonic and perinatal classification system of biliary atresia (BA), we present a child with an antenatal diagnosis of choledochal cyst (CC) associated with BA and review the published literature. METHODS: Medline and Pubmed were searched for "BA and CC," "cystic biliary atresia," "BA and cysts," and "biliary cystic malformations." RESULTS: A 7-week-old with an antenatal diagnosis of CC was found to have BA associated with CC. The literature search identified 88 cases of BA with CC. Sixty-seven cases had type 1 BA (atresia of the common bile duct), 2 had type 2 BA (atresia of the common hepatic duct), and 19 had type 3 BA (atresia of the porta hepatis). Of the 27 cases of antenatal diagnosis of BA with CC only 1 had associated congenital anomalies. Outcome analysis showed poor outcomes were significantly more common (P = .009) and occurred earlier (P = .0249) in patients with type 3 BA. Children with type 3 BA were 5.4 times more likely to develop poor outcomes compared with type 1 (hazard ratio, 5.4; 95% confidence interval, 1.03-27.8). CONCLUSIONS: BA associated with CC forms a distinct subtype of BA, characterized by a preponderance of type 1 BA, a relatively good clinical outcome after surgery, and an absence of associated congenital anomalies. Antenatal diagnosis of many affected infants supports their inclusion within the embryonic BA group and suggests that a broader interpretation of the embryonic phenotype and further classification of BA based on genetic susceptibility may be required.

Biliary Atresia↗

PubMed2006

Commonly used preparations for colonoscopy: efficacy, tolerability, and safety--a Canadian Association of Gastroenterology position paper.

INTRODUCTION: The increased demand for colonoscopy, coupled with the introduction of new bowel cleansing preparations and recent caution advisories in Canada, has prompted a review of bowel preparations by the Canadian Association of Gastroenterology. METHODS: The present review was conducted by the Clinical Affairs group of committees including the endoscopy, hepatobiliary/transplant, liaison, pediatrics, practice affairs and regional representation committees, along with the assistance of Canadian experts in the field. An effort was made to systematically assess randomized prospective trials evaluating commonly used bowel cleansing preparations in Canada. RESULTS: Polyethylene glycol (PEG)-; sodium phosphate (NaP)-; magnesium citrate (Mg-citrate)-; and sodium picosulphate, citric acid and magnesium oxide (PSMC)-containing preparations were reviewed. Regimens of PEG 2 L with bisacodyl (10 mg to 20 mg) or Mg-citrate (296 mL) are as effective as standard PEG 4 L regimens, but are better tolerated. NaP preparations appear more effective and better tolerated than standard PEG solutions. PSMC has good efficacy and tolerability but head-to-head trials with NaP solutions remain few, and conclusions equivocal. Adequate hydration during preparation and up to the time of colonoscopy is critical in minimizing side effects and improving bowel cleansing in patients receiving NaP and PSMC preparations. All preparations may cause adverse events, including rare, serious outcomes. NaP should not be used in patients with cardiac or renal dysfunction (PEG solution is preferable in these patients), bowel obstruction or ascites, and caution should be exercised when used in patients with pre-existing electrolyte disturbances, those taking medications that may affect electrolyte levels and elderly or debilitated patients. Health Canada's recommended NaP dosing for most patients is two 45 mL doses 24 h apart. However, both safety and efficacy data on this dosing schedule are lacking. Many members of the Canadian Association of Gastroenterology expert panel administer both doses within 24 h, as studied in clinical trials, after careful one-on-one discussion of risks and benefits in carefully selected patients. Safety data on PSMC and combination preparations in North America are limited and clinicians are encouraged to keep abreast of developments in this area. CONCLUSIONS: All four preparations reviewed provided effective bowel cleansing for colonoscopy in the majority of patients, with varying tolerability. Adequate hydration is essential in patients receiving the preparations.

Colonoscopy↗

PubMed2002

How useful is fecal pancreatic elastase 1 as a marker of exocrine pancreatic disease?

OBJECTIVES: To evaluate the role of fecal elastase 1 (E1) as a marker of exocrine pancreatic insufficiency (PI). STUDY DESIGN: Fecal E1 was measured in patient groups with (1) failure to thrive but no pancreatic or intestinal disease (disease control patients); (2) PI; (3) pancreatic sufficiency; and (4) steatorrhea caused by a variety of intestinal diseases. RESULTS: Fecal E1 in all disease control patients exceeded 200 microg/g stool. Only 1 (2%) of 50 patients with PI exceeded the minimum reference value of 100 microg/g stool. In contrast, 3 (11%) of 28 patients with pancreatic sufficiency (with Shwachman-Diamond syndrome) had fecal E1 concentrations <100 microg/g stool, as did 5 (20%) of 25 patients with steatorrhea from intestinal causes, all of whom had diluted feces caused by short gut. CONCLUSIONS: Fecal E1 is a useful noninvasive screening test of PI in childhood. A negative test (>100 microg/g stool) had 99% predictive value for ruling out PI. However, a positive test in those with short gut or Shwachman-Diamond syndrome must be interpreted with caution.

Adolescent↗