Acute and Chronic Pancreatitis

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Acute and Chronic Pancreatitis Diagnosis of Acute Pancreatitis Two of the following three features: Darwin L. Conwell, MD,MS Associate Director BWH Center for Pancreatic Disease Brigham and Women s Hospital Harvard Medical School Characteristic abdominal pain Amylase and/or lipase > 3 times upper limit of normal CT scan showing characteristic findings of AP No Disclosures Acute Pancreatitis: Pathophysiology Acute Pancreatitis Clinical Presentation Epigastric pain, nausea, vomiting Diagnosis Clinical evaluation Serology (amylase,lipase, LFTs) Imaging ULTRASOUND (early), CT (later) Prognosis Ranson criteria < 48 h APACHE II > 48 h BISAP Score BUN Trajectory Acute Pancreatitis: Differential Diagnosis Acute Pancreatitis: Red Flags Mesenteric ischemia Perforated gastric or duodenal ulcer Biliary colic Dissecting aortic aneurysm Intestinal obstruction Inferior wall myocardial infarction

Acute Pancreatitis: Ranson Criteria Acute Pancreatitis: Mortality Acute Pancreatitis: Etiology Acute Pancreatitis Reasonable attempts etiology Affecting acute management Historical clues Alcohol, cholecystectomy, medications, weight loss, age Blood tests Abdominal ultrasound Contrast enhanced CT MRI / MRCP Acute Pancreatitis: CT Scan Definitions Acute Pancreatitis: CT Scan Interstitial Pancreatitis Focal or diffuse enlargement of the pancreas with enhancement of the parenchyma in response to IV contrast Blood supply maintained Necrotizing Pancreatitis Diffuse or focal areas of nonviable pancreatic parenchyma Blood supply lost

Acute Pancreatitis: Systemic effects Acute Pancreatitis: Systemic effects Acute Pancreatitis: Organ Failure Acute Pancreatitis: SIRS and Survival Acute Pancreatitis: CT implications Acute Pancreatitis: CT Guided Percutaneous Aspiration

Acute Pancreatitis Treatment Mild: Supportive care, IVFs, analgesics Severe: CT Scan, Necrosis vs. Interstitial Aggressive hydration, pain management Percutaneous aspiration / gram stain Surgical debridement Antibiotics Nutrition support Gallstones Emergent ERCP Case 1: Acute Pancreatitis On Hospital Day 3: 65 year old with persistent abd pain, fever, nausea, vomiting Exam: febrile 101.5, stable vital signs, tenderness, flank echymosis, rebound and absent bowel sounds Labs: Serology amylase lipase >2,000 Liver chemistries normal Imaging: Ultrasound: Normal gallbladder, bile ducts and pancreas head CT scan: edematous pancreas with 30% non-enhanced area Complications ARDS, ARF, SIRS Pseudocyst (symptomatic), abscess (E coli) Should we start prophylactic antibiotics? Acute Pancreatitis: Pharmacologic Issues Antimicrobial Use Prophylactic Antibiotics: Meta-analysis Infection Feeding Enteral versus parenteral nutrition Mortality Hughes S, et al. Gastroenterol Clin N Am. 2007;36:313-323. Pederzoli P, et al. Surg Gynecol Obstet. 1993;176:480-483. Bai Yu, et al. Am J Gastroenterol 2008;103:104-110. Prophylactic Antibiotics: Meta-analysis 329 patients 6 RCTs No reduction in infected necrosis No reduction in mortality No reduction in nonpancreatic infections No reduction in surgical intervention No reduction in hospital stay Mazaki, et al. BJS 2006;93:674-684. Case 1: Acute Pancreatitis On Hospital Day 3: 65 year old with persistent abd pain, fever, nausea, vomiting Exam: febrile 101.5, stable vital signs, tenderness, flank echymosis, rebound and absent bowel sounds Labs: Serology amylase lipase >2,000 Liver chemistries normal Imaging: Ultrasound: Normal gallbladder, bile ducts and pancreas head CT scan: edematous pancreas with 30% non-enhanced area Should we start prophylactic antibiotics? NO

Case 1: Acute Pancreatitis On Hospital Day 5: 65 year old with persistent abd pain, fever, nausea, vomiting Exam: febrile 101.5, stable vital signs, tenderness, flank echymosis, rebound and absent bowel sounds Labs: Serology amylase lipase >2,000 Liver chemistries normal Imaging: Ultrasound: Normal gallbladder, bile ducts and pancreas head CT scan: edematous pancreas with 30% non-enhanced area Should we feed patient? If so, what route delivery? Acute Pancreatitis: Nutrition Activation of intracellular proteolytic enzymes Food further stimulates production of trypsin Cornerstone of AP mgmt: pancreatic rest Long-term resting fasting the pancreas led to: High rates of body nitrogen and protein loss Increased mortality O Keefe SJ, et al. Gastroenterol Clin N Am. 2007(36):297-312. Acute Pancreatitis: Nutrition to Improve Outcomes 1) Tissue repair and recovery Meta-analysis: Nutritional Support and Infection Hypermetabolic and catabolic disease state Necrotizing disease: accelerated amino acid losses 2) Modulates inflammatory response Partially generated within the gut lumen and mucosa Prevention of intestinal ischemia Prevention of luminal stasis and bacterial overgrowth O Keefe SJ, et al. Gastroenterol Clin N Am. 2007(36):297-312. Sitzmann J, et al. Surg Gynecol Obstet. 1989;168:311-6. Marik PE, Zaloga GP. Br Med J. 2004;328(7453):1407-13. Meta-analysis: Endpoints Case 1: Acute Pancreatitis On Hospital Day 5: 65 year old with persistent abd pain, fever, nausea, vomiting Exam: febrile 100.5, stable vital signs, tenderness, flank echymosis, rebound and absent bowel sounds Labs: Serology amylase lipase >2,000 Liver chemistries normal Imaging: Ultrasound: Normal gallbladder, bile ducts and pancreas head CT scan: edematous pancreas with 30% non-enhanced area Additional: Reduced hospital stay in enteral feeding groups (mean reduction 2.9days, p<0.001) Should we feed patient? YES If so, what route delivery? ENTERAL, jejunal preferred Marik PE, Zaloga GP. Br Med J. 2004;328(7453):1407-13.

Drug-Induced Pancreatitis Pancreatic Necrosis (confirmed by CT scan) High suspicion of infected necrosis Obtain CT-guided FNA + Gram Stain (usually after 7-10 days) Negative culture Positive culture May repeat FNA q5-7 days if clinically indicated Clinically stable Targeted antimicrobial therapy Clinically unstable Prompt surgical debridement vs. delayed surgical or endoscopic debridement vs. no debridement Prompt surgical, percutaneous, or endoscopic debridement Badalov N, et al. Clin Gastroenterol Hepatol. 2007;5(6):648-661. Berzin, et al. Gastroenterol Clin N Am. 2006,35:393-407. Medical History 1700 s Chronic Pancreatitis: Overview 1788 Cawley reported a free living young man who died of emaciation and diabetes and whose postmortem examination revealed multiple pancreatic calculi Progressive, irreversible damage Exocrine and endocrine cells Exocrine insufficiency steatorrhea Endocrine insufficiency diabetes Incidence 3.5 to 10 per 100,000 population Marks IN, Bank S., Bockus Gastroenterology. 4th ed. 1985 Pancreatic Steatorrhea Chronic Pancreatitis AGA, Gastroenterology Teaching Project 2006. A. Computed tomography B. Endoscopic retrograde pancreatography C. Endoscopic ultrasound D. Histology

TIGAR-O Toxic-metabolic Alcohol Tobacco Hypercalcemia Chronic renal failure Toxins Idiopathic Early onset Late onset Tropical Genetic Hereditary pancreatitis (cationic trypsinogen mutation) CFTR mutations SPINK 1 mutations Alpha-1 antitrypsin deficiency TIGAR-O Autoimmune Isolated autoimmune CP Syndromic autoimmune CP (PSC, Sjögren's-associated, etc.) Recurrent and severe AP Postnecrotic Recurrent acute pancreatitis Ischemic/vascular Obstructive Pancreas divisum Intrapapillary mucinous tumor Ductal adenocarcinoma Gastroenterology 2001, Vol. 120, Etemad B, Whitcomb DC. 682 707. Gastroenterology 2001, Vol. 120, Etemad B, Whitcomb DC. 682 707. SAPE Hypothesis (Sentinel AP Event) Chronic Pancreatitis A Step A: Acinar cell stimulation Alcohol, gallstone, TG, oxidative stress Pain Management C D B Step B: Sentinel Event Early: pro-inflammatory respone Late: Stellate cells, pro-fibrotic response Step C: Removal of stimulus Abstinence Cholecystectomy Lipid lowering agents Step D: Recurrent stimulation Stellate cell mediated periacinar fibrosis Malabsorption: exocrine dysfunction Pancreatic Diabetes: endocrine dysfunction Stevens T, Conwell DL. Am J Gastroenterol 2004;99:2256. Whitcomb D, Best Prac and Res in Clin Gastro 2002;16:347. Kozarek R, et al. Gastroenterology. 1998;115:765-776. CP Pain Neurobiology CP pain leads to changes in cortical projections of the nociceptive system Gastroenterology 2007;132:1546-1556 Probably the most important article in years on chronic pancreatic pain neurobiology. This publication has opened the door for further investigations in CP pain management CP pain includes activation and modulation of visceral afferents, descending pain pathways and central neuroplasticity. The degree of central sensitization was 17% in controls and 36% in CP patients. Pancreas 2007; 35(1): 22-9 Further evidence supporting neurobiology & central processing in CP pain Thorascopic splanchnicectomy reduces nociceptive visceral input as evidenced by a decreased narcotic requirement but appears to have no affect on central sensitization in CP patients by quantitative sensory testing. European J Pain 2007; 11: 437-443 Case 2: Chronic Pancreatitis CE is a 58YOM presenting for evaluation of 1-yr hx of epigastric pain radiating to the back and 10lb wt loss. He describes the pain as constant, present on most days, often debilitating (10/10 pain scale), and oily bowel movements SH: alcohol consumption 5-6 beers/day for 25 years but reduced since onset pain Normal CBC, electrolytes, liver chemistries, amylase, and lipase Upper GI endoscopy: no signs PUD CT abdomen: scattered parenchymal calcifications, dilation of main pancreatic duct to 5 mm max diameter, no mass 1. What are the pharmacologic options for pain management?

Pain Management: Step-wise Management Low-fat diet, non-narcotic analgesics, no alcohol Therapeutic trial of enzyme 1-2 months, reassess pain Dose: 16,000-64,000 units lipase qac Narcotic analgesia Endoscopic, surgical management Case 2: Chronic Pancreatitis 1. What are the pharmacologic options for pain management? Reasonable to: Initiate a trial of pancreatic enzymes If failed response: Analgesics +/- pain modifying agents Endoscopic therapy Surgery American Gastroenterological Association. Gastroenterology. 1998;115:763-764. Chronic Pancreatitis Pain Management Malabsorption: exocrine dysfunction Pancreatic Diabetes: endocrine dysfunction Kozarek R, et al. Gastroenterology. 1998;115:765-776. Pancreatic Enzyme Replacement Therapy Mechanism for steatorrhea: Lipase synthesis Lipase denaturation Fat digestion by lipase: Healthy subjects: Gastric lipase activity ~10% total lipase activity CP: Gastric lipase activity ~90% of all lipase activity Unable to compensate for all lipid digestion required Lipase Activity Low [HCO3] CP High [HCO3] Healthy Subjects Duodenal ph Exogenous Enzymes Dutta SK, et al. Dig Dis Sci. 1979;23:775-80 Pancreatic Enzyme Replacement Therapy Vast array of formulations available Pharmacologic principles Goal of enzyme replacement: Achieve normal [enzyme] in duodenum Goal of disease state management: Eliminate malabsorption (reduce steatorrhea) Maintain adequate nutrition (prevent wt loss) Ferrone M, et al. Pharmacotherapy. 2007;27(6):911-920. Pezzilli R, et al. Dig Liver Dis. 2005;37:181-9. Pancreatic Enzyme Pharmacotherapy Commercially available pancrelipase preparations: Creon Zenprep Differences in efficacy? Ferrone M, et al. Pharmacotherapy. 2007;27(6):911-920.

Pancreatic Enzyme Pharmacotherapy 1. Conventional, uncoated: Susceptible to inactivation by acidity of stomach Increase dose Acid suppressive therapy 2. Enteric-coated microencapsulated: ph-sensitive coating Microspheres, minimicrospheres, microtablets Distribution in chyme throughout gastric emptying 3. Enteric-coated, high buffered Contain bicarbonate Ferrone M, et al. Pharmacotherapy. 2007;27(6):911-920. Kalnins D, et al. J Pediatr Gastroenterol Nutr. 2006;42:256-61. Treatment Regimens: Malabsorption Dose approximated by lipase content Mean duodenal lipase activity: 40-60 units/ml Adults: ~25,000-40,000 units lipase/meal Children, adolescents: ~500-2000 units lipase/kg/meal (or 500-4000 units lipase/g fat) Goal: Reduce steatorrhea to <15g/day of fat Titrate dose based to effect Considerations if treatment failure: Check compliance Product integrity Acid suppression Ferrone M, et al. Pharmacotherapy. 2007;27(6):911-920. Layer PT, et al. Pancreas. 1992;7:745. Chronic Pancreatitis Pain Management Malabsorption: exocrine dysfunction Pancreatic Diabetes: endocrine dysfunction Pancreatic Diabetes Glucose intolerance Overt diabetes: late in the course of disease Pancreatic diabetes: Typically insulin-requiring Different from type 1 diabetes Pancreatic alpha cells also affected May lead to increased risk hypoglycemia Kozarek R, et al. Gastroenterology. 1998;115:765-776. Del Prato S, et al. Diabetes Reviews. 1993;1:260. Malka D, et al. Gastroenterology. 2000;119:1324. Treatment Options for CP Good Anatomy based Macroscopic Better Physiology based Microscopic Best Pathogenesis based Molecular Pathogenesis Based Therapy: Best Pancreatic stellate cells activation Molecular mediators TGF-B, PDGF Pro-inflammatory cytokines IL-1, IL-6, TNF-alpha Molecular pathways MAPK, PI3K Novel molecular targets Potential therapeutic agents Talukdar R., J Gastro and Hep 2008; 23(1): 34 41.

Question 1 Enteric coated enzymes are preferable over uncoated enzymes in the management of steatorrhea? A.True B.False Question 1 Enteric coated enzymes are preferable over uncoated enzymes in the management of steatorrhea? A.True B.False Answer A: True Protection of lipase from low ph in stomach Question 2 Which of the following diagnostic tests has the highest accuracy at detecting early / mild chronic pancreatitis? A. ERCP B.MRCP C. Pancreas function test D.EUS Question 2 Answer: C, Pancreas Function Test Structural Changes Pancreas Function Early Late Sxs Abd Pain(10y) Dyspepsia Steatorrhea(29y) Diabetes(38y) Cancer (55y) PFT Normal Abnormal ERCP Normal Minimal Moderate Severe MRCP Normal T1 signal Ductal Duct/secretion EUS 0-2 3-4 4-5 >5 Question 3 Which of the following is not part of the Ranson Criteria for assessment of Acute Pancreatitis Severity? WBC Gender Age Glucose LDH Question 3 Answer C: Gender Which of the following is not part of the Ranson Criteria for assessment of Acute Pancreatitis Severity? A. WBC B. Gender C. Age D. Glucose E. LDH

Pancreatitis Resources Harrisons and Cecil stextbooks of Medicine Practice Guidelines for Acute Pancreatitis: American College of Gastroenterology American Gastroenterological Association Practice guidelines for acute pancreatitis, pain management in chronic pancreatitis Gastroenterology Clinics of North America: