Letter of Medical Necessity
Ankylosing Spondylitis (HLA-B27) Genotyping
A physician may want to include a letter of medical necessity with a preauthorization request or
claim submission, to facilitate the insurance review process for the benefit of the patient. Most
major insurance companies consider genetic testing medically necessary to establish a
molecular diagnosis of an inheritable disease when specific conditions are met;
1. The patient displays clinical features, or is at risk of inheriting the mutation(s) in question
(pre-symptomatic);
2. The result of the test will directly impact the treatment being delivered to the patient; and
3. After history, physical examination, genetic counseling, and completion of conventional
diagnostic studies, a definitive diagnosis remains uncertain.
We encourage health care providers to cover as many of the following points as possible that
are applicable to the patient:
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Explanation that the genetic test has been ordered by a physician;
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Explanation that the patient has received genetic counseling;
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Explanation of the medical necessity for the test requested;
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Treatment plan, including specific statements about the anticipated impact of the
genetic test on the patient’s medical management;
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Patient's diagnosis and prognosis, including age of onset;
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If family history is cited, provide as much family history information as possible
(including specifics about relationship to patient and for affected family members.
Alternatively, a detailed three-generation pedigree that contains this information could
be attached and referred to in the body of the letter.
Please carefully read the entire letter of medical necessity to make sure it makes sense for your
patient.
<On Office Letterhead>
<Date>
<Insurance Company Name>
<Medical Director>, MD
<Address 1>
<Address 2>
<City>, <ST> <ZIP>
Re: <Patient Full Name>
Member ID: <Enter Member ID>
DOB: <MM/DD/YYYY>
Group ID: <Enter Group ID>
Dear Medical Director:
I am writing this letter on behalf of my patient, <Patient Name>, to request coverage for the
Ankylosing Spondylitis (HLA-B27) Genotyping test. This test is important to aid in diagnosis in
individuals symptomatic for ankylosing spondylitis (AS) and related disorders (Reiter syndrome,
anterior uveitis, psoriatic arthritis, and inflammatory bowel disease) or to test at-risk relatives
for a known HLA-B27 mutation.
Human Leukocyte Antigen (HLA) B27 (subtypes B*2701-2759) [1] is a class I surface antigen
encoded by the B locus in the major histocompatibility complex (MHC) on chromosome 6 and
presents antigenic peptides (derived from self and non-self antigens) to T cells. HLA-B27 is
strongly associated with ankylosing spondylitis (AS), and other associated inflammatory
diseases referred to as "spondyloarthropathies". HLA-B27 is found in 88% of patients with
ankylosing spondylitis. It is inherited in a Mendelian fashion, and first-degree relatives of HLAB27 positive patients with spondyloarthropathies are at 50% risk of inheriting HLA-B27. The
chance that an HLA-B27 patient will develop spondyloarthritis or eye disease is 1 in 4.
The spondyloarthritides, as a subset, have several distinguishing features that are shared
among them. The diseases are seronegative by definition. There are common, contributing
genetic factors including the human leukocyte antigen (HLA) B27. Axial involvement, including
sacroiliitis, can be seen in all and is essential for the diagnosis of ankylosing spondylitis.
Enthesitis, or inflammatory changes of the tendon and ligament attachment to bone, is the
primary pathologic phenomenon. The spondyloarthritides share many extra-articular features
including uveitis, dermatitis, and colitis. Ankylosing spondylitis is a chronic, systemic,
inflammatory disease that affects primarily the sacroiliac joints and spine. Certain peripheral
joints and tendons can also be affected, and extra-articular manifestations may be present.
The HLA-B27 test may be ordered as part of a group of tests used to diagnose and evaluate
conditions causing arthritis-like chronic joint pain, stiffness, and inflammation especially when
suspecting ankylosing spondylitis but the disease is in an early stage and the vertebrae in the
spine have not yet undergone the characteristic changes that would be seen on X-ray.
HLA-B27 is on located on chromosome 6 encoding for a protein with many functions such as
phagocytosis in infectious disease, graft rejection and ability to recognize self from non-self in
the immune system. The genotyping test is performed using polymerase chain reaction (PCR)
followed by melting curve analysis.
I am requesting this test for <Patient Name>. This letter documents the medical necessity of
this test to assist in the treatment, prognosis and diagnosis of <his/her> ankylosing spondylitis
(AS) or related disorders (Reiter syndrome, anterior uveitis, psoriatic arthritis, and inflammatory
bowel disease). Below is additional information about the patient’s medical history and
potential impact of the test results on the patient’s medical management.
Patient History and Diagnosis:
<Patient Name> is a <Age> -year-old <Gender > with a suspected diagnosis of ankylosing
spondylitis (AS) or related disorders (Reiter syndrome, anterior uveitis, psoriatic arthritis, and
inflammatory bowel disease), based on the following symptoms and clinical findings:
1. <Symptom/Diagnosis #1 with ICD-9 code>
2. <Symptom/Diagnosis #2 with ICD-9 code>
Family History: (if applicable)
<Patient Name> also has a family history, including:
<Family History>
Clinical Impression:
The patient’s symptoms and clinical history, in addition to other diagnostic testing is suggestive
of ankylosing spondylitis (AS) or related disorders (Reiter syndrome, anterior uveitis, psoriatic
arthritis, and inflammatory bowel disease) The “Ankylosing Spondylitis (HLA-B27) Genotyping”
test will play an important role in establishing the presence of specific mutations which will
guide appropriate medical management of the patient. This test can assist the patient by:


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Confirmation of ankylosing spondylitis (AS) or related disorders (Reiter syndrome,
anterior uveitis, psoriatic arthritis, and inflammatory bowel disease),
predict clinical behavior of disease,
aid in treatment decisions.
I recommend that you support this request for coverage of the Ankylosing Spondylitis (HLAB27) Genotyping by PCR testing for <Patient Name> through ARUP Laboratories test code
0050392, Federal Tax ID# 87-0403206 / NPI# 1376548271 with the following CPT codes 81374.
Please note that this test is performed for clinical management in a laboratory that is CLIA
approved for high complexity testing. Please feel free to contact me at <Physician Phone> if
you require additional information.
Sincerely,
<Signature>
<Print Name>
References
1. Khan M A, Ankylosing spondylitis and related spondyloarthropathies: the dramatic advances
in the past decade. Rheumatology (2011) 50 (4): 637-639.
2. McVeigh C M, Cairns AP, Diagnosis and management of ankylosing spondylitis. British
Medical Journal. 2006 September 16; 333(7568): 581–585
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC1570004/
3. Dixon A, HLA-B27 and risk of ankylosing spondylitis. British Medical Journal. 1978;2:961.5
(Published 30 September 1978)
4. Lucotte G, et al. DNA typing of HLA-B27 by polymerase chain reaction. Mol Cell Probe
1997;11:313–5.
5. Rudwaleit M, Khan MA, Sieper J. The challenge of diagnosis and classification in early
ankylosing spondylitis: do we need new criteria? Arthritis Rheum. 2005 Apr;52(4):1000-8.
6. Colbert R A, DeLay M L, Layh-Schmitt G, Sowders D P, HLA-B27 misfolding and
spondyloarthropathies. Prion. 2009 Jan-Mar; 3(1): 15–26.
7. http://labtestsonline.org/understanding/analytes/hla-b27/tab/test