Mayo Test Catalog, (Sorted By Test Name) - Mayo Medical ...

HP
83019
HSEP
81087
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 rate of destruction. HS can result from abnormalities involving several red cell membrane
proteins, such as band 3, spectrin, and ankyrin. Most often HS is diagnosed in childhood, adolescence,
or early adult life. The diagnosis of HS is usually made by a combination of patient and family history,
laboratory evidence of hemolysis, and review of a peripheral blood smear. The osmotic fragility test is
usually markedly abnormal in these cases. However, factors such as age, sex, and medications can
affect the osmotic fragility test. This evaluation combines osmotic fragility testing with a newly
developed flow cytometry assay to provide complementary information in the evaluation of patients
with suspected HS.
Current as of January 3, 2013 2:22 pm CST 800-533-1710 or 507-266-5700 or MayoMedicalLaboratories.com Page 925