July 22, 2017

Acute Pancreatitis - Symptoms, Diagnosis and Management

OVERVIEW OF ACUTE PANCREATITIS

Pancreatitis is an inflammatory process in which pancreatic enzymes autodigest (i.e. self-digests) the gland. The gland sometimes heals without any impairment of function or any morphologic changes; this process is known as acute pancreatitis. Pancreatitis can also recur intermittently, contributing to the functional and morphologic loss of the gland; recurrent attacks are referred to as chronic pancreatitis.

Both forms of pancreatitis may present in the emergency department (ED) with acute clinical findings. Recognizing patients with severe acute pancreatitis as soon as possible is critical for achieving optimal outcomes.

This article focuses on the recognition of the signs and symptoms, and also the management of acute pancreatitis.

Signs and symptoms

Symptoms of acute pancreatitis include the following:
  • Abdominal pain (cardinal symptom): Characteristically dull, boring, and steady; usually sudden in onset and gradually becoming more severe until reaching a constant ache; most often located in the upper abdomen and may radiate directly through to the back
  • Nausea and vomiting, sometimes with anorexia
  • Diarrhea
Patients may have a history of the following:
  • Recent operative or other invasive procedures
  • Family history of hypertriglyceridemia
  • Previous biliary colic and binge alcohol consumption (major causes of acute pancreatitis)
The following physical findings may be noted, varying with the severity of the disease:
  • Fever (76%) and tachycardia (65%); hypotension
  • Abdominal tenderness, muscular guarding (68%), and distention (65%); diminished or absent bowel sounds
  • Jaundice (28%)
  • Dyspnea (10%); tachypnea; basilar rales, especially in the left lung
  • In severe cases, hemodynamic instability (10%) and hematemesis or melena (5%); pale, diaphoretic, and listless appearance
  • Occasionally, extremity muscular spasm secondary to hypocalcemia
The following uncommon physical findings are associated with severe necrotizing pancreatitis:
  • Cullen sign (bluish discoloration around the umbilicus resulting from hemoperitoneum)
  • Grey-Turner sign (reddish-brown discoloration along the flanks resulting from retroperitoneal blood dissecting along tissue planes); more commonly, patients may have a ruddy erythema in the flanks secondary to extravasated pancreatic exudate
  • Erythematous skin nodules, usually no larger than 1 cm and typically located on extensor skin surfaces; polyarthritis

Diagnosis

Once a working diagnosis of acute pancreatitis is reached, laboratory tests are obtained to support the clinical impression, to help define the etiology, and to look for complications. Diagnostic imaging is unnecessary in most cases but may be obtained under certain conditions. Image-guided aspiration may be useful. Genetic testing may be considered.

Laboratory tests to support the clinical impression, include the following:
  • Serum amylase and lipase
  • Liver-associated enzymes
  • Blood urea nitrogen (BUN), creatinine, and electrolytes
  • Blood glucose
  • Serum cholesterol and triglyceride
  • Complete blood count (CBC) and hematocrit; NLR
  • C-reactive protein (CRP)
  • Arterial blood gas values
  • Serum lactic dehydrogenase (LDH) and bicarbonate
  • Immunoglobulin G4 (IgG4)
Diagnostic imaging is unnecessary in most cases but may be obtained when the diagnosis is in doubt, when pancreatitis is severe, or when a given study might provide specific information needed to answer a clinical question. Modalities employed include the following:
  • Abdominal radiography (limited role): Kidneys-ureters-bladder (KUB) radiography with the patient upright is primarily performed to detect free air in the abdomen
  • Abdominal ultrasonography (most useful initial test in determining the etiology, and is the technique of choice for detecting gallstones)
  • Endoscopic ultrasonography (EUS) (used mainly for detection of microlithiasis and periampullary lesions not easily revealed by other methods)
  • Abdominal computed tomography (CT) scanning (generally not indicated for patients with mild pancreatitis but always indicated for those with severe acute pancreatitis)
  • Endoscopic retrograde cholangiopancreatography (ERCP; to be used with extreme caution in this disease and never as a first-line diagnostic tool)
  • Magnetic resonance cholangiopancreatography (MRCP; not as sensitive as ERCP but safer and noninvasive)
Other diagnostic modalities include the following:
  • CT-guided or EUS-guided aspiration and drainage
  • Genetic testing
Acute pancreatitis is broadly classified as either mild or severe. According to the Atlanta classification, severe acute pancreatitis is signaled by the following[1]:
  • Evidence of organ failure (eg, systolic blood pressure below 90 mm Hg, arterial partial pressure of oxygen [Pa O2] 60 mm Hg or lower, serum creatinine level 2 mg/dL or higher, GI bleeding amounting to 500 mL or more in 24 hours)
  • Local complications (eg, necrosis, abscess, pseudocyst)
  • Ranson score of 3 or higher or APACHE score of 8 or higher

Management

Management depends largely on severity. Medical management of mild acute pancreatitis is relatively straightforward; however, patients with severe acute pancreatitis require intensive care. The goals of medical management are to provide aggressive supportive care, to decrease inflammation, to limit infection or superinfection, and to identify and treat complications as appropriate. Surgical intervention (open or minimally invasive) is indicated in selected cases.

Initial supportive care includes the following:
  • Fluid resuscitation
  • Nutritional support
Antibiotic therapy is employed as follows:
  • Antibiotics (usually of the imipenem class) should be used in any case of pancreatitis complicated by infected pancreatic necrosis but should not be given routinely for fever, especially early
  • Antibiotic prophylaxis in severe pancreatitis is controversial; routine use of antibiotics as prophylaxis against infection in severe acute pancreatitis is not currently recommended
Surgical intervention (open or minimally invasive) is indicated when an anatomic complication amenable to a mechanical solution is present. Procedures appropriate for specific conditions involving pancreatitis include the following:
  • Gallstone pancreatitis: Cholecystectomy
  • Pancreatic duct disruption: Image-guided percutaneous placement of a drainage tube into the fluid collection; stent or tube placement via ERCP; in refractory cases, distal pancreatectomy or a Whipple procedure
  • Pseudocysts: None necessary in most cases; for large or symptomatic pseudocysts, percutaneous aspiration, endoscopic transpapillary or transmural techniques, or surgical management
  • Infected pancreatic necrosis: Image-guided aspiration; necrosectomy
  • Pancreatic abscess: Percutaneous catheter drainage and antibiotics; if no response, surgical debridement and drainage

Patient Education

Educate patients about the disease, and advise them to avoid alcohol in binge amounts and to discontinue any risk factor, such as fatty meals and abdominal trauma.

Related: More articles on Diseases and Conditions

Reference(s):
1). Banks PA, Bollen TL, Dervenis C, Gooszen HG, Johnson CD, Sarr MG, et al. Classification of acute pancreatitis--2012: revision of the Atlanta classification and definitions by international consensus. Gut. 2013 Jan. 62(1):102-11. [Medline].
2). Gardner TB , Berk BS , Anand BS, Patel T, Talavera F, Williams N, Yakshe P. Acute Pancreatitis. Medscape, Updated: Apr 01, 2015. http://emedicine.medscape.com/article/181364-overview. Accessed 4 December 2015.

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