New Findings in Endoscopy Research

The endoscopy team at The Children’s Hospital of Philadelphia considers research an integral part of providing the very best care, and continues to expand its investigations.

“Part of being an effective clinician is learning from your current patients for the sake of your future patients,” says Petar Mamula, MD, endoscopy suite director. “Our efforts are reflective of the overall philosophy at CHOP, to continually improve through research.”

Recent and current endoscopy research

During the second and third year of his fellowship at CHOP, Benjamin Sahn, MD, has been a dedicated endoscopy research fellow. Here’s a roundup of recent and current endoscopy research efforts.

CHOP-Penn Study Shows Pediatric EUS Successful, Efficacious

Certain complex endoscopic procedures, such as endoscopic ultrasound (EUS) and endoscopic retrograde cholangiopancreatography (ERCP), while relatively common in adults, are rarely performed in the pediatric population. However, as the number of children with pancreatobiliary diseases increases, so too does the need for pediatric expertise in these procedures.

Adding to a growing body of research examining the use of such procedures in children, CHOP and the Hospital of the University of Pennsylvania (HUP) teamed up to conduct the largest single-center review to date of pediatric EUS.

The report found EUS in children to be technically successful and efficacious with a low risk of immediate complications and a meaningful impact on clinical care. In nearly a quarter of cases, a new diagnosis was established.

The study team reviewed all pediatric EUS cases (patients < 21 years) performed at HUP between May 2007 and November 2012. The study covered 64 completed EUS procedures in 58 patients. Among the findings:

• The indications included: pseudocyst drainage (4); evaluation of GI luminal lesions (13); pancreatitis (10); insulinoma localization (8); pancreatic anomalies (7); tumor surveillance (6); abdominal pain suspected to be of pancreatobiliary origin (5); and other (5).
• Fine needle aspiration was used in 13 patients.
• EUS achieved the diagnostic or therapeutic goal or ruled out suspected pathology to avoid further testing in 90 percent of cases.
• In 24 percent of cases, a new diagnosis was established.

The CHOP-Penn review provides further support to the effectiveness of EUS in children and is a valuable addition to the small body of literature on the topic. The study was completed by Mamula, Sahn and fellow Maire Conrad, MD, along with HUP adult gastroenterologists. The abstract was presented at Digestive Disease Week 2013 (Gastrointest Endosc. 77(5S): AB246, 2013).

The findings follow a previous CHOP-Penn effort that showed another complex procedure common in adults is also safe and effective in children. Last year, the teams published one of the largest single-center review of pediatric ERCP, finding a high rate of technical success (cannulation) and a low rate of serious complications.

Other recent findings

Incidence of perforation

A team published the largest single-center series describing perforation adverse events with pediatric endoscopy and colonoscopy. Using proprietary software, the team combed the endoscopy database at CHOP for procedures between February 1998 and November 2008. In addition, 36 pediatric gastroenterologists performing endoscopies during the study period were interviewed to recollect cases of perforation during or after endoscopy, and a review of the existing medical chart was performed for the cases of perforation. The review found that over the 11-year study period, 30,177 endoscopic procedures were performed: 21,345 esophagogastroduodenoscopies (EGD), 7,126 colonoscopies, and 1,706 flexible sigmoidoscopies.

Of these, 1,262 (4.2 percent) were considered therapeutic procedures. Nine cases of perforation were identified and four excluded. Of the remaining five perforations, three occurred with EGD for an overall incidence of 0.014 percent and two with colonoscopies for an incidence of 0.028 percent. Two of the five perforations occurred after therapeutic EGD, for an overall perforation incidence with all therapeutic procedures of 0.16 percent.

Safety of electrolyte-free polyethylene glycol powder (PEG-P, Miralax®) as preparation for colonoscopy

The endoscopy suite team recently completed a 175-patient trial evaluating the safety of one-day, weight-based PEG-P bowel preparation for colonoscopy. The primary aim of this study was to determine the proportion of patients with significant serum chemistry abnormalities pre- and at the time of colonoscopy. Secondary objectives were prep tolerance and bowel cleansing efficacy.

Results indicated that PEG-P prep is safe for children. However, subjects ≤ 7 years old seem to be at a higher risk of hypoglycemia compared to older children. There was a higher rate of hypokalemia noted at the time of colonoscopy compared to pre-bowel prep, although this is likely of no clinical significance.

This preparation regimen was difficult to tolerate in more than half of subjects, but the vast majority were able to complete it. On a scale of 0-10 (10=most difficult), 47 percent of subjects rated the prep 0-3, and 29 percent rated it 7-10, with symptoms including abdominal pain, nausea and vomiting.

The colon cleanliness rating was excellent or good in 79 percent of subjects, fair in 14 percent, and poor or inadequate in 6 percent and 1 percent, respectively.

In progress

In addition to several multicenter trials, current investigations by the endoscopy team at CHOP include:

Fecal microbiota transplant for recurrent C. difficile infection (CDI)

The team recently started a trial to determine the efficacy of fecal microbiota transplant (FMT) for pediatric patients with recurrent CDI, an infection of the intestinal tract that frequently leads to symptoms of diarrhea and abdominal pain, at times severe enough to require hospitalization. Patients with one relapse are at increased risk for additional relapse of this infection. While the precise mechanism of the infection is not understood, it is thought to be secondary to alterations in the intestinal bacterial structure, or intestinal microbiota. FMT involves the administration of fecal material from a healthy individual (donor) into a sick patient with relapsing CDI during a colonoscopy in order to restore a healthy diverse gut microbiota. FMT is offered to children with multiple episodes of CDI unable to be treated with antibiotic therapy. In addition to healthy children with recurrent CDI, FMT will be offered to pediatric patients with inflammatory bowel disease with recurrent CDI.

Incidence of duodenal hematoma with esophagogastroduodenoscopy (EGD)

The team is conducting a 13-year retrospective review of all EGD cases complicated by the development of a duodenal hematoma, a rare but possibly underreported complication of EGD with duodenal biopsy. The study team is collaborating with Michael Nance, MD, attending surgeon and director of the Pediatric Trauma Program at CHOP, to compare the patients with duodenal hematomas after EGD with those who develop the same injury after blunt abdominal trauma.

The results of the study have just been submitted for publication. There were 14 cases of duodenal hematoma after EGD and a total of 26,905 cases of EGD with duodenal biopsy during the 13-year study period, for an incidence of 1 in 1,922 EGD with duodenal biopsy procedures. Both endoscopy and trauma cohorts presented with similar symptoms and timing, typically presenting to medical attention in the first 72 hours after onset. All patients improved within three weeks without need for a surgical intervention. This is the largest pediatric case series of duodenal hematoma to date and one of the first to compare these two etiologies directly.

Dilatation strategies in esophageal achalasia

The endoscopy team is designing a clinical trial to evaluate dilatation strategies in pediatric esophageal achalasia and will be obtaining a new technology called EsoFLIP® (functional lumen imaging probe) to perform and measure success of the dilation.