Chronic pancreatitis

Chronic pancreatitis
Classification and external resources
ICD-10	K86.0-K86.1
ICD-9	577.1
OMIM	167800
DiseasesDB	9559
MedlinePlus	000221
eMedicine	med/1721
MeSH	D050500

Chronic pancreatitis is a long-standing inflammation of the pancreas that alters its normal structure and functions. It can present as episodes of acute inflammation in a previously injured pancreas, or as chronic damage with persistent pain or malabsorption.

Symptoms

Patients with chronic pancreatitis usually present with persistent abdominal pain or steatorrhea resulting from malabsorption of the fats in food. Diabetes is a common complication due to the chronic pancreatic damage and may require treatment with insulin. Some patients with chronic pancreatitis look very sick, while others don't appear to be unhealthy at all.

Considerable weight loss, due to malabsorption, is evident in a high percentage of patients, and can continue to be a health problem as the condition progresses. The patient may also complain about pain related to their food intake, especially those meals containing a high percentage of fats and protein. Some chronic pancreatitis patients do not experience pain while others suffer from constant, debilitating pain. Weight loss can also be attributed to a reduction in food intake in patients with severe abdominal pain.

Causes

• Alcohol
• Tropical (nutritional)
• Hereditary
• Trypsinogen and inhibitory protein defects
• Cystic fibrosis
• Idiopathic
• Trauma
• Hypercalcaemia
• Calcific stones

In developed countries, the most common causes of chronic pancreatitis are alcohol and idiopathic.

Across the rest of the world malnutrition and associated dietary factors have been implicated. In a small group of patients chronic pancreatitis has been shown to be hereditary, inherited as an autosomal dominant condition with variable penetrance. Almost all patients with cystic fibrosis have established chronic pancreatitis, usually from birth. Cystic fibrosis gene mutations have also been identified in patients with chronic pancreatitis but in whom there were no other manifestations of cystic fibrosis. Obstruction of the pancreatic duct because of either a benign or malignant process may result in chronic pancreatitis. Congenital abnormalities of the pancreatic duct, in particular pancreas divisum, have been implicated.″^[1]

Diagnosis

The diagnosis of chronic pancreatitis is typically based on tests on pancreatic structure and function, as direct biopsy of the pancreas is considered excessively risky. Serum amylase and lipase may or may not be moderately elevated in cases of chronic pancreatitis, owing to the uncertain levels of productive cell damage, though elevated lipase is the more likely found of the two. Amylase and lipase are nearly always found elevated in the acute condition along with an elevated CRP  inflammatory marker that is broadly in line with the severity of the condition. A secretin stimulation test is considered the gold standard functional test for diagnosis of chronic pancreatitis but not often used clinically. The observation that bi-carbonate production is impaired early in chronic pancreatitis has led to the rationale of use of this test in early stages of disease (sensitivity of 95%). Other common tests used to determine chronic pancreatitis are faecal elastase measurement in stool, serum trypsinogen, Computed tomography (CT), ultrasound, EUS, MRI, ERCP and MRCP. Pancreatic calcification can often be seen on plain abdominal X-rays, as well as CT scans.

There are other non-specific laboratory studies useful in diagnosis of chronic pancreatitis. Serum bilirubin and alkaline phosphatase can be elevated, indicating stricturing of the common bile duct due to edema, fibrosis or cancer. When the chronic pancreatitis is due to an autoimmune process, elevations in ESR, IgG4, rheumatoid factor, ANA and antismooth muscle antibody may be seen. The common symptom of chronic pancreatitis, steatorrhea, can be diagnosed by two different studies: Sudan chemical staining of feces or fecal fat excretion of 7 grams or more over a 24hr period on a 100g fat diet. To check for pancreatic exocrine dysfunction, the most sensitive and specific test is the measurement of fecal elastase, which can be done with a single stool sample, and a value of less than 200 ug/g indicates pancreatic insufficiency.^[2]

Treatment

The different treatment modalities for management of chronic pancreatitis are medical measures, therapeutic endoscopy and surgery.^[3] Treatment is directed, when possible, to the underlying cause, and to relieve pain and malabsorption. Insulin dependent diabetes mellitus may occur and need long term insulin therapy.

The abdominal pain can be very severe and require high doses of analgesics, sometimes including opiates. Disability and mood problems are common, although early diagnosis and support can make these problems manageable. Alcohol cessation and dietary modifications (low-fat diet) are important to manage pain and slow the calcific process. Recent research indicates smoking may be a high-risk factor.

Pancreatic Enzyme Supplementation

Replacement pancreatic enzymes are often effective in treating the malabsorption and steatorrhea. However, the outcome from 6 randomized trials has been inconclusive regarding pain reduction.^[4]

While the outcome of trials regarding pain reduction with pancreatic enzyme replacement is inconclusive, some patients do have pain reduction with enzyme replacement and since they are relatively safe, giving enzyme replacement to a chronic pancreatitis patient is an acceptable step in treatment for most patients. Treatment may be more likely to be successful in those without involvement of large ducts and those with idiopathic pancreatitis. Patients with alcoholic pancreatitis may be less likely to respond.^[2]

Surgery

Traditional Surgery for Chronic Pancreatitis tends to be divided into two areas - resectional and drainage procedures.^[5] New and proven transplantation options prevent the patient from becoming diabetic following the surgical removal (resection) of their pancreas. This is achieved by transplanting back in the patients own insulin-producing beta cells.^[6]

See also

• Acute pancreatitis
• Exocrine pancreatic insufficiency

References

1. ^ Kumar P, Clark M. (eds.) (2005) Kumar & Clark Clinical medicine. 6th ed. Edinburgh: W B Saunders.
2. ^ ^{a b} Freedman SD. "Clinical manifestations and diagnosis of chronic pancreatitis in adults". UpToDate. http://www.uptodate.com/patients/content/topic.do?topicKey=~EzkfCtNwumVrg. 
3. ^ American Gastroenterological Association Medical Position Statement (1998). "American Gastroenterological Association Medical Position Statement: treatment of pain in chronic pancreatitis". Gastroenterology 115 (3): 763–4. doi:10.1016/S0016-5085(98)70156-8. PMID 9721174. 
4. ^ Warshaw AL, Banks PA, Fernández-Del Castillo C (1998). "AGA technical review: treatment of pain in chronic pancreatitis". Gastroenterology 115 (3): 765–76. doi:10.1016/S0016-5085(98)70157-X. PMID 9721175. 
5. ^ Society for Surgery of the Alimentary Tract (SSAT) (2004). "Operative treatment for chronic pancreatitis". http://www.ngc.gov/summary/summary.aspx?ss=15&doc_id=5506. Retrieved 2007-06-09. 
6. ^ Center for Cellular Transplantation at the University of Arizona - www.pancreatitiscenter.org

^Smoking and risk of acute and chronic pancreatitis - http://www.ncbi.nlm.nih.gov/pubmed/19307524

External links

• VIDEO - Chronic Pancreatitis: Recent Advances and Ongoing Challenges, Jeffery B. Matthews, MD, speaks at the University of Wisconsin School of Medicine and Public Health (2007)
• Medical Information and Treatment of Chronic Pancreatitis