gutsandgrowth

Home | About Jay Hochman -Pediatric Gastroenterology Blog | Archives

Postgraduate Course Notes -Pancreatitis Module

October 29, 2013 7:00 am

When and how to assess pancreatic function: an update for clinicians –Sohail Z. Husain, MD (page 31)

Reviewed methods of detecting pancreatic insufficiency

Indirect (non-stimulatory) Methods

Stool:

Fecal Fat Analysis: Coefficient of fat absorption (CFA): (fat intake – fat in stool / fat intake) * 100
Normal > 93% (> 85% in less than 6 mo.
old)
72 hr collection gold standard

ELASTASE-1: Stable, specific for human pancreas

Normal > 200 μg elastase/g stool
Particularly good for monitoring the development of PI in patients with CF
Low levels (false-positive) with diarrhea
Only detects severe PI

Other tests

Chymotrypsin: less sensitive; requires discontinuation of enzymes
Steatocrit: cheap; has low sensitivity
Serum
Breath
Direct (stimulatory)
Dreiling tube
Endoscopic pancreatic function testing (ePFT)
Secretin-enhanced MRCP (sMRCP)

Causes of Pancreatic Insufficiency

-85% of patients with Cystic Fibrosis have pancreatic insufficiency

Shwachman-Diamond Syndrome

Mutation in SBDS, found in ~90% of SDS patients
PI affects almost all SDS pts

Johanson-Blizzard syndrome (JBS): Key findings

PI
Severe developmental delay
Hypoplasia or aplasia of the nasal wings

Pearson marrow pancreas syndrome Key findings: Severe hypoplastic,macrocytic anemia, Pancreatic insufficiency (due to pancreatic fibrosis)

Diagnosis: Clinical picture, High serum lactate/pyruvate, Southern blot for mtDNA rearrangements

Other causes of pancreatic insufficiency

Chronic pancreatitis
Pancreatic obliteration after severe, acute pancreatitis
Pancreatic tumors
Celiac disease
Diabetes
IBD

Managing nutrition in cystic fibrosis: the role of the pediatric gastroenterologist — Sarah Jane Schwarzenberg, M.D. (page 41)

Good nutrition status correlates with better heights, better lung function, and better survival. (Presentation did not delve into the issue of potential reverse causation.)

Patients with a Weight-for-Age percentile >50% at age 4 years reached a much higher height-for-age early in life and maintained this advantage into adulthood
Pulmonary function (FEV1%predicted) was much lower in CF patients with WAP<10% at age 4 years. This finding tracked through age 18 years.
Small bowel overgrowth is common in CF
Small bowel bacterial overgrowth contributes to poor nutritional intake and increased nutrient losses

Options to improve nutrition in CF

Review and optimize enzyme dose and adherence
Review patient’s diet with an experienced CF dietician
Consider adding a PPI to improve intestinal pH
Consider confounding disease
Evaluate for signs and symptoms of small bowel overgrowth and consider trial of metronidazole or rifaximin
Ask patient about abdominal pain
Evaluate for gastroparesis
Evaluate for DIOS
Consider non-CF gastrointestinal disease
Consider oral glucose tolerance test

Therapy to improve nutrition

Time-limited interventions
Behavior therapy to improve intake
Offer oral supplements
Consider cyproheptadine as an appetite stimulant
Consider a G-tube for nocturnal feeds
Consider Endocrinology consult

Beyond the Basics in the Management of Pancreatitis –Aliye Uc, M.D. (page 51)

INSPPIRE To Study Acute Recurrent and Chronic Pancreatitis in Children-180 children from 14 centers enrolled to study the etiologies, epidemiology, natural history and outcome.

Pediatric Acute Recurrent and Chronic Pancreatitis-etiologies

Genetic (49%) (61 of 91 tested)
PRSS1-30%, CFTR-22%, SPINK1-14%, CTRC-3%
Obstructive (34%)
Idiopathic (20%)
Toxic-Metabolic (17%)
Autoimmune (3%)

Genetics of Pancreatitis:

1. PRSS1 (cationic trypsinogen): Autosomal dominant, 80% penetrance, Mutations are due to increased activation or decreased inactivation of trypsin (i.e. R122H, N29I).

2. SPINK1 (trypsin inhibitor): Autosomal recessive/complex inheritance, 2% have mutation, <1% have pancreatitis (i.e. N34S), Pancreatitis is dose-related (homozygous>>>het), Associated with other mutations (CFTR)

3. CFTR (>1700 mutations):

2 Severe mutations = Cystic Fibrosis
1 severe, 1 mild mutation = mild or atypical CF, ARP, CP
CF carriers = 3-4 fold increase risk in pancreatitis.
1 any +SPINK1 = CFTR-associated pancreatitis
1 any +divisum = CFTR-associated pancreatitis

4.New Modifier Genes in ARP and CP

CTRC (trypsin degrading enzyme)
CASR (a calcium-sensing receptor)
CLDN2 (tight junction protein on X chromosome)
CPA1 (Carboxypeptidase 1) increased riskf for CP in younger patients

Management:

Unclear if antioxidants helpful for pain.
The role of pancreatic enzymes in CP is equivocal.

Diet

When to start feeds? depends on the severity of AP, OK to start early; correlate with clinical readiness, abd pain
What mode of nutrition? prefer enteral over TPN, NG vs. NJ
What to feed? recent studies in adults with mild AP support full diet

(Moraes JM et al. J Clin Gastroenterol 2010 44:517)

No evidence that low-fat diet is helpful

IV Fluids: With acute presentation, Lactated Ringer’s preferred over Normal saline.

NG Suction

Not shown to decrease symptoms,mortality or hospital stay.
May be useful if: severe gastric distention, refractory nausea and vomiting, or obstruction seen on abdominal x-ray