Results are reported in 10-21 days.
Shwachman-Diamond Syndrome (SDS) is a recessively-inherited multisystem disorder occurring in approximately 1/75,000 births that causes exocrine pancreatic insufficiency, hematological abnormalities including bone marrow failure and malignancy, and skeletal defects due to metaphyseal dysostosis.
Diagnosis is often made in early childhood due to failure to thrive, abnormal stools, and recurrent infections. Rib cage abnormalities and short stature are common signs of irregular bone growth and maturation that characterize SDS. Hepatomegaly and elevated liver enzymes are found in many very young patients, but these tend to resolve in later childhood. Approximately half of patients become pancreatic sufficient over time. Neutropenia, thrombocytopenia or anemia are present in nearly all patients and at least one quarter of patients develop aplastic anemia, myelodysplastic syndrome, or leukemia.
Treatments for SDS can include pancreatic enzyme replacement, surgery to improve skeletal function, routine blood and bone marrow analyses for monitoring, blood transfusions, chemotherapy, and hematopoietic stem cell transplant.This condition is also called Shwachman-Bodian-Diamond Syndrome and was formerly called congenital lipomatosis of the pancreas.
Approximately 75% of SDS alleles result from gene conversion events that introduce mutated sequence from a pseudogene into the SBDS gene. Genotype does not appear to correlate with phenotype for presence or severity of symptoms.
The Ambry Test is a full gene sequence analysis of the SBDS gene. Assay design prevents unwanted amplification of the pseudogene. Approximately 90% of patients will test positive for at least one SBDS mutation.
- Diagnostic confirmation in patients suspected to have SDS
- Mutation definition in known affected patients
- Familial mutation testing in relatives to determine carrier status
- Prenatal diagnosis on CVS or amniotic fluid for known carrier couples
General Test Information
The Ambry Test: Shwachman-Diamond Syndrome
The following CPT Codes for The Ambry Test reflects Ambry Genetics’ interpretation of CPT coding requirements based on AMA guidelines:
Ambry Test: Shwachman-Diamond Syndrome
83891, 83894, 83898, 83904, 83909, 83912
CPT codes are provided only as a guide to assist you in billing. CPT coding is the sole responsibility of the billing party.
Disclaimer:
This test was developed and its performance characteristics were determined by Ambry Genetics Corporation. The laboratory is regulated under the Clinical Laboratory Improvement Amendments 2003 as qualified to perform nonwaived testing. The Ambry Test: Shwachman-Diamond Syndrome analyzes the following types of mutations: nucleotide substitutions, small deletions, small insertions, and small indels. It is not intended to analyze the following types of mutations: gross insertions, gross rearrangements, deep intronic variations, and other unknown abnormalities. The pattern of mutation types varies with the gene tested and the Ambry Test detects a high but variable percentage of known and unknown mutants of the classes stated. A negative result from the analysis cannot rule out the possibility that the tested individual carries a rare unexamined mutation or mutation in the undetectable group. The Ambry Test: Shwachman-Diamond Syndrome is designed and validated to be capable of detecting ~95% of described SBDS mutations (considering ~5% to be the other types of mutations). The detection rate in affected patients is ~78%. Shwachman-Diamond Syndrome is a complex clinical disorder, which in some cases is due to alterations in the SBDS gene generally detected by the Ambry Test: Shwachman-Diamond Syndrome except as noted above. Mutations in other genes or the regions not tested by the Ambry Test: Shwachman-Diamond Syndrome can also give rise to clinical conditions similar or identical to Shwachman-Diamond Syndrome. Although molecular tests are highly accurate, rare diagnostic errors may occur. Possible diagnostic errors include sample mix-up, erroneous paternity identification, technical errors, and genotyping errors. Genotyping errors can result from trace contamination of PCR reactions, from maternal cell contamination in fetal samples, from rare genetic variants, which interfere with analysis, or from other sources. This report does not represent medical advice. Any questions, suggestions, or concerns regarding interpretation of results should be forwarded to a genetic counselor, medical geneticist, or physician skilled in interpretation of the relevant medical literature. References are available upon request.
