Sorted By Test Name - Mayo Medical Laboratories

MSP2
83305
prevent metastatic MTC and can reduce the morbidity and mortality associated with MTC. Biochemical
screening can increase the detection rate in asymptomatic individuals with a family history of MEN 2.
This testing involves the measurement of calcitonin with and without stimulation by calcium or
pentagastrin to detect early signs of thyroid disease (hyperplasia of calcitonin-producing cells [C-cells] of
the thyroid). Missense mutations in the RET proto-oncogene (located on chromosome 10) are responsible
for the variable phenotypes of MEN 2A, MEN 2B, and FMTC. The majority of mutations occur at
conserved cysteine residues within exons 10 and 11. Additional mutations in exons 13, 14, 15 and 16
account for the preponderance of other RET mutations. Taken together, mutations in these codons account
for approximately 98% of MEN 2A, >99% of MEN2B, and 96% of FMTC. Although gain of function
mutations in the RET proto-oncogene may result in MEN2, loss of function mutations have been reported
in patients with Hirschsprung disease (HSCR). It has been reported that up to 50% of familial cases of
HSCR and 3% to 35% of sporadic HSCR are due to RET germline mutations. However, most of the
mutations that cause HSCR occur outside of the codons that are typically mutated in MEN2. Therefore,
the absence of a mutation utilizing this test does not rule out the diagnosis of HSCR.
Useful For: Confirmation of diagnosis of multiple endocrine neoplasia type 2 (MEN 2), MEN 2B, and
familial medullary thyroid carcinoma (FMTC) Documentation of germline mutation to distinguish FMTC
from sporadic multifocal medullary thyroid carcinoma
Interpretation: An interpretive report will be provided.
Reference Values:
An interpretive report will be provided.
Clinical References: 1. Hansford J, Mulligan L: Multiple endocrine neoplasia type 2 and RET: from
neoplasia to neurogenesis. J Med Genet 2000;37(11):817-827 2. Marini F, Falchetti A, Del Monte F,
Carbonell Sala S, et al: Multiple endocrine neoplasia type 2. Orphanet J Rare Dis. 2006 Nov 14;1:45 3.
Ruiz-Ferrer M. Fernandez RM. Antinolo G. et al: A complex additive model of inheritance for
Hirschsprung disease is supported by both RET mutations and predisposing RET haplotypes. Gen Med
2006;8(11):704-710
Multiple Sclerosis (MS) Profile
Clinical Information: Multiple sclerosis (MS) is a chronic inflammatory demyelinating disease
characterized by visual, motor, and sensory disturbances. The diagnosis of MS is dependent on clinical,
radiological, and laboratory findings. The detection of increased intrathecal immunoglobulin (Ig)
synthesis is the basis for current diagnostic laboratory tests for MS. These tests include the cerebrospinal
fluid (CSF) IgG index and CSF oligoclonal band detection.
Useful For: Diagnosing multiple sclerosis, especially helpful in patients with equivocal clinical or
radiological findings
Interpretation: Oligoclonal banding (OCB): > or =4 cerebrospinal fluid (CSF)-specific bands are
consistent with multiple sclerosis (MS). CSF IgG index: >0.85 is consistent with MS. Abnormal CSF IgG
indexes and OCB patterns have been reported in 70% to 80% of MS patients. If both tests are performed,
at least 1 of the tests has been reported to be positive in >90% of multiple sclerosis patients. A newer
methodology for OCB detection, isoelectric focusing, is utilized in this test and has been reported to be
more sensitive (90%-95%). The presence of OCB or elevated CSF IgG index is unrelated to disease
activity.
Reference Values:
OLIGOCLONAL BANDS