Sorted By Test Name - Mayo Medical Laboratories

HP
83019
HSEP
81087
involvement of other loci or unidentified mutations in the cationic trypsinogen gene.
Useful For: Confirming the diagnosis of hereditary pancreatitis in patients with chronic pancreatitis
who also have a family member with a documented PRSS1 gene mutation Screening of at-risk individuals
when a mutation has been identified in an affected family member
Interpretation: An interpretive report will be provided.
Reference Values:
An interpretive report will be provided.
Clinical References: 1. Teich N, Mossner J: Hereditary chronic pancreatitis. Best Pract Res Clin
Gastroenterol. 2008;22(1):115-30 2. Howes N, Greenhalf W, Stocken DD, Neoptolemos JP: Cationic
trypsinogen mutations and pancreatitis. Clin Lab Med 2005;25:39-59 3. Ellis I: Genetic counseling for
hereditary pancreatitis--the role of molecular genetics testing for the cationic trypsinogen gene, cystic
fibrosis and serine protease inhibitor Kazal type 1. Gastroenterol Clin North Am 2004;33:839-854
Hereditary Pancreatitis, Mutation Screen
Clinical Information: Hereditary pancreatitis (HP) is a rare autosomal dominant disorder, with
approximately 80% penetrance. HP is characterized by early onset of acute pancreatitis during childhood
or early adolescence. The acute pancreatitis in these patients generally progresses to chronic pancreatitis
by adulthood and can eventually lead to both exocrine and endocrine pancreatic insufficiency. Patients
with HP are also at an increased risk for developing pancreatic cancer. Studies have estimated the lifetime
risk of developing pancreatic cancer to be as high as 40%. HP cannot be clinically distinguished from
other forms of pancreatitis. However, PRSS1 mutations are generally restricted to individuals with a
family history of pancreatitis. PRSS1 mutations are infrequently found in patients with alcohol-induced
and tropical pancreatitis. The protease serine 1 or cationic trypsinogen (PRSS1) gene is located on
chromosome 7. It has been reported that as many as 80% of patients with symptomatic hereditary
pancreatitis have a causative PRSS1 mutation. Although several mutations have been identified, the
Arg122His (R122H), Asn29Ile (N29I), and Ala16Val (A16V) mutations have been identified as the
primary causative defects in HP. The phenotype of patients with these 3 mutations is quite similar, sharing
many clinical features, though there are some differences. Data suggests that the R122H mutation results
in more severe disease and earlier onset of symptoms, while the A16V mutation has reduced penetrance.
Although these 3 alterations account for >90% of mutations detected in the cationic trypsinogen gene, the
inability to identify mutations in approximately 20% of families with HP suggests the possible
involvement of other loci or unidentified mutations in the cationic trypsinogen gene.
Useful For: Confirming the diagnosis of hereditary pancreatitis (HP) in patients with chronic
pancreatitis Ruling out HP in patients with chronic pancreatitis
Interpretation: An interpretive report will be provided.
Reference Values:
An interpretive report will be provided.
Clinical References: 1. Teich N, Mossner J: Hereditary chronic pancreatitis. Best Pract Res Clin
Gastroenterol 2008;22(1):115-30 2. Howes N, Greenhalf W, Stocken DD, Neoptolemos JP: Cationic
trypsinogen mutations and pancreatitis. Clin Lab Med 2005;25:39-59 3. Ellis I: Genetic counseling for
hereditary pancreatitis-the role of molecular genetics testing for the cationic trypsinogen gene, cystic
fibrosis and serine protease inhibitor Kazal type 1. Gastroenterol Clin North Am 2004;33:839-854
Hereditary Spherocytosis Evaluation
Clinical Information: The hemolytic anemias are a group of anemias that are characterized by an
increased destruction of RBCs. Anemias may be divided into inherited or acquired. Hereditary
spherocytosis (HS), also known as congenital hemolytic anemia, is inherited as a non sex-linked dominant
trait. HS is caused by a RBC membrane defect. The RBCs are spherocytic in shape and show an increased
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