#NASPGHAN18 Highlights and Tweets (part 1)

I did not make it to this year’s meeting but did get a chance to catch up on a lot information via the PG 2018 Syllabus and based on information posted online.

Here are a couple of highlights for me:

Slides from postgraduate course on CVS from Dr. Katja Kovacic

The slide from Dr. Lightdale (pg 22 in Syllabus) below suggests it is OK for scope if platelets >20K and OK for biopsies if platelets >50K. It is worth noting that some adult data indicate that even lower biospy thresholds are reasonable for biopsies (Post: Lower Endoscopic Thresholds for Thrombocytopenia). As always, one needs to consider carefully the risks compared with the benefits.

From Postgraduate Course

 

 

Disclaimer: These blog posts are for educational purposes only. Specific dosing of medications/diets (along with potential adverse effects) should be confirmed by prescribing physician/nutritionist.  This content is not a substitute for medical advice, diagnosis or treatment provided by a qualified healthcare provider. Always seek the advice of your physician or other qualified health provider with any questions you may have regarding a condition.

Predicting Future Liver Disease with GGT Levels in Biliary Atresia Patients

A recent study (AJ Freeman, VL Ng, S Harpavat, A Hrycko, Z Apted, P Bulut, T Leong, SJ Karpen. Clin Gastroenterol Hepatol 2017; 15: 1133-35) describes the predictive value of γ-glutamyltransferase (GGT) in predicting thrombocytopenia/portal hypertension among biliary atresia patients.

In this retrospective study from three centers who had followup for at least 4 years, GGT values at 2 years of age were examined among biliary atresia patients (n=46) who continued with their native liver.

Key findings:

  • GGT ≥100 U/L had a predictive positive relationship with thrombocytopenia at 4, 5, and 6 years of age.  Patients with elevated GGT had lower platelet count (160 vs. 211) and their values continued to decline. GGT ≥100 U/L at 2 yrs predicted thrombocytopenia (<150) at age 4 with a sensitivity of 0.88, specificity of 0.57.
  • Patients with normal GGT values had “essentially stable platelet counts over the next 4 years.” GGT <100 U/L at 2 yrs predicted a low risk of thrombocytopenia with negative predictive value of 0.89, 0.92, and 0.93 at age 4, 5, and 6 respectively.

My take: This study quantitates a useful point –patients with biliary atresia and elevated GGT values are likely to develop evidence of portal hypertension.

Brevard, NC

Lower Endoscopic Thresholds for Thrombocytopenia

According to an advances in endoscopy report (Ross, WA. Gastroenterology Hepatology 2015; 11: 115-17), lower platelet thresholds are indicated for many endoscopic procedures.  The author works at MD Anderson Cancer Center in Houston.

Key points:

  • We feel that the traditional threshold of 50,000 platelets/microliter that many doctors adhere to or aim for should be put aside, and a lower platelet threshold of perhaps 25,000 or 30,000 platelets/microliter should be employed for endoscopic procedures, including biopsies.
  • “We found that therapeutic maneuvers could be performed to control bleeding.”
  • “This change would require fewer platelet transfusions to prepare a patient for endoscopy.”
  • Based on their published experience (Krishna SG, et al. “Saftey of endoscopic interventions in patients with thrombocytopenia.” Gastrointest Endosc 2014; 80: 425-34), the author notes that “polypectomy could probably be performed with a platelet count under 50,000/microliter, likely in the 30,000-40,000/microliter range, particularly if the polyp was small (<10 mm).”  They caution that cold snare technique may be safer in this setting but is not suitable for larger polyps.
  • Other preventative measures include stopping aspirin use, limiting the number and size of biopsies, and using non thermal means to help stop bleeding, such as clips or injections.
  • “Performing an endoscopic procedure in a patient with an extremely low platelet count, such as 5000/microliter, is associated with a high risk of bleeding.”

“If the procedure is just a simple biopsy, a platelet count of 25,000/microliter to 30,000/microliter should suffice.”

Take-home message: While the data that the author references is derived from adults, it is likely that in pediatrics that endoscopy, if needed, can be performed in patients with platelet counts less than 50,000/microliter.

Endoscopy Module -Postgraduate Course Notes

Advances in Hemostasis for Upper GI Bleeding Brad Barth, MD, MPH  (page 77)

Upper GI Bleeding

Effect of IV PPI on patients with UGI bleeding PRIOR to EGD

  • 6 trials including 2223 patients
  • No significant difference in mortality, rebleeding or need for surgery compared to controls
  • DID significantly reduce rates of high risk stigmata identified on EGD
  • DID significantly decrease the need for endoscopic therapy
  • Reference: Sreedharan A, Martin J, Leontiadis G, et al. Proton pump inhibitor treatment initiated prior to endoscopic diagnosis in upper gastrointestinal bleeding. Cochrane Database of Systematic Reviews 2010

 

Upper GI Bleeding – Proton Pump Inhibitors/Prokinetics

  • Omeprazole 1 mg/kg q 12 hours  (Solana, et al. J Pediatr 2013:162:776-82)
  • Proposed PPI drip dose: 1 mg/kg bolus followed by 0.1 mg/kg/hour infusion
  • IV erythromycin or metoclopramide; infuse 20-120 minutes prior to endoscopy in patients with acute UGIB; decreased need for repeat endoscopy to determine cause and site of bleeding. Prokinetic did NOT affect transfusion requirements, duration of stay, need for surgery. Reference: Barkun et al. Prokinetics in acute upper GI bleeding:a metaanalysis. GIE 2010;17:126-132

Upper GI Bleeding —Other points:

  • Epinephrine alone is RARELY enough
  • Non bleeding adherent clot has 8-35% chance of rebleeding in adults. Consider removing it CAREFULLY!
  • A conservative transfusion strategy is usually appropriate

Useful References

Surveillance Endoscopies: The established, the debated, and the unknown –Mitchell Shub, M.D. (page 85)

“Beware of false knowledge; it is more dangerous than ignorance.” —George Bernard Shaw

Familial Adenomatous Polyposis

Surveillance protocol: Age of initial evaluation/Type of procedure/Frequency

  • Colon 10 – 12 y of age (Sooner: family h/o aggressive disease) -Flex sig or Colonoscopy, 1 – 2 y
  • Upper GI tract 20 – 25 y or at initial colonoscopy
  • EGD and side viewing scope, 1 – 3 y
  • Post-colectomy (pouch) 6 – 12 mo. after surgery, Flex sig 1 y (6 mo. If retained rectum)
  • Small bowel: capsule or MRI, frequency unknown

Peutz-Jeghers Syndrome: begin screening at age 8 years or when symptomatic with colonoscopy, EGD, and small bowel imaging (?capsule vs alternatives); then every 2-3 years

Juvenile Polyposis Syndrome: begin screening at age 10-15 years or when symptomatic with colonoscopy, EGD, and  possibly small bowel imaging (?capsule vs alternatives); then every 1-3 years

Discussed guidelines for IBD cancer surveillance and for Barrett’s esophagus

  • For UC, start surveillance 8-10 years after diagnosis.
  • For Crohn’s with ~1/2 colon (or more) involvement, follow same guidelines
  • For coexisting PSC, annual surveillance
  • Barrett’s esophagus in children: adenocarcinoma very rare, evidence lacking to develop surveillance schedule

Expanding the view: Update on Upper GI StricturesMark A. Gilger, M.D. (page 95)

Why balloons for kids (for dilatation)?

You can see what you’re doing

  • Blind pouches
  • Abnormal mucosa
  • Caustic injury
  • Epidermolysis bullosa
  • Already requires general anesthesia
  • Ability to wire through narrow strictures
  • Ability to use radiographic assistance

Tip: Can use vegetable spray (eg. Pam) to make advancement of balloon catheter easy

How to do balloon dilation

  • Inflate balloon to ½ desired initial atmospheres & re‐check placement
  • Begin dilation at to 1‐2 mm more than initial estimated stricture diameter
  • Hold for 1 minute/dilation
  • •ove balloon catheter in and out during dilation;  if balloon moves freely, increase diameter by 1mm.  If stricture moves with the balloon, hold x 1 minute, then done
  • Oh, oh, there’s blood! Good! No blood, no dilation.
  • After dilation, carefully advance endoscope through the stricture; if resistance stop, can try cork‐screw maneuver
  • Document everything; especially stricture location (CM from incisors), dilation diameters (to help you next time)

Adjunct therapy for recalcitrant strictures  –adjunct therapy to sustain dilation needs further study

  • Oral & intravenous corticosteriods
  • Injectable corticosteroids – Thins the mucosa, OK 1‐2 times, but not repeated
  • Mitomycin C
  • Acid reduction
  • Stents

Endoscopy in the high‐risk patient: Keeping your patient safeJenifer R. Lightdale, MD, MPH (page 63)

Safety of Pediatric GI Procedures

  • Peds‐CORI data from >10,000 procedures
  • Overall rate of complications 2.3%: risk of hypoxia 1.5%; risk of bleeding 0.3%

Examples of pediatric populations at increased risk for perforation

  • History of caustic ingestion
  • Esophageal atresia/tracheo‐esophageal fistula
  • Severe duodenitis
  • Severe ulcerative colitis
  • Patients with multiple co‐morbidities (i.e. Type I diabetes, cerbrovascular disease, peripheral vascular disease, renal insufficiency, liver disease)
  • Ehlers‐Danlos Syndrome (Vascular Type)

Pre‐procedure Assessment –lends itself to a checklist 

Thrombocytopenia -Current recommendations

  • EGD ok if platelets >20,000/mL
  • Biopsies ok if platelets >50,000/mL

Bleeding –discussed high risk conditions

Decreasing Risk of Perforation:

  • Avoiding excessive pressure
  • Avoiding premature cutting of a polyp – Coagulate before cutting
  • Avoiding blind intubation of the lumen

Decreasing Risks of Infection

  • SBE Prophylaxis– generally NOT indicated in diagnostic procedures. Congenital heart disease is complex & may be needed on a case‐by‐case basis
  • Single‐dose cephalexin has been shown to decrease peristomal infection during PEG placement
  • Prophylactic antibiotics recommended for cirrhotic patients admitted with GI hemorrhage

Postgraduate Course Syllabus (posted with permission) with complete slides of above lectures: PG Syllabus

Related blog references:

Disclaimer: These blog posts are for educational purposes only. Specific dosing of medications (along with potential adverse effects) and specific medical management interventions should be confirmed by prescribing physician.  Application of the information in a particular situation remains the professional responsibility of the practitioner.

ELEVATE study

Another clever acronym for the following:  Eltrombopag Evaluated for Its Ability to Overcome Thrombocyopenia and Enable Procedures (NEJM 2012; 367: 716-24).

Eltrombopag is an oral thrombopoietin-receptor agonist which is approved for use in chronic immune thrombocytopenia.

This double-blind, placebo-controlled trial evaluated whether eltrombopag increased platelet counts and reduced platelet transfusions in patients with chronic liver disease & platelet counts less than 50,000 per cubic millimeter.  145 patients received eltrombopag (75 mg once a day) and 147 received placebo.  Patients received therapy for 14 days. Elective procedures were scheduled no more than 5 days after the final dose of study medication (days 15 to 19).

Key findings:

  • Transfusions of platelets were reduced in the treatment group: 28% of patients compared with 81% in placebo group.
  • No differences in significant bleeding episodes noted.
  • Portal venous thrombosis was increased in treatment group with 6 patients compared with 1 patient in placebo group.

Study limitation: no standard practice with regard to use of platelet transfusions for thrombocytopenia (especially with platelet counts between 50,000-80,000)

Platelet transfusions can be problematic with cirrhosis.  Platelet transfusions have a short duration of efficacy, reactions to transfusions can occur, and multiple transfusions can result in antiplatelet antibodies. Nevertheless, the conclusions from this study: ‘until better identification of risk factors for the development of thrombosis…have been conducted, eltrombopag is not recommended as an alternative to platelet transfusion.’