Download Tuberous Sclerosis Panel

[DATE]
Patient: [PATIENT_FIRST_NAME] [PATIENT_LAST_NAME]
Insurance Company: [INSURANCE_COMPANY_NAME]
Subscriber Name: [POLICY_HOLDER_NAME]
Policy #: [POLICY_NUMBER]
Dear Claims Specialist,
I am writing this letter of medical necessity on behalf of the patient [PATIENT_FIRST_NAME] [PATIENT_LAST_NAME] to
request coverage for genetic testing for Tuberous Sclerosis Complex (TSC) offered through GeneDx, a high complexity
CLIA certified laboratory located in Gaithersburg, Maryland. The purpose of this test is to identify a pathogenic
mutation(s) in the nuclear genome, and the methodology used by this laboratory is able to find these mutations with a
very high degree of sensitivity. Results of this test will allow better care and treatment of the patient. In addition, it
will allow for proper genetic counseling and family planning. This test is performed by next generation sequencing
(aka massive parallel sequencing), which has a detection rate of 99%.
Information on Patient’s Condition:
[PATIENT_FIRST_NAME] is a [PATIENT_AGE] year-old [PATIENT_GENDER] suspected to have tuberous sclerosis
complex (TSC). Additionally, [HIS_HER] family history is notable for [FAMILIY HISTORY]. Based on
[PATIENT_FIRST_NAME]’s clinical symptoms and results of the routine diagnostic tests suggest a diagnosis of Tuberous
Sclerosis Complex. However, the only way to confirm this diagnosis is to perform genetic testing on this patient.
Results from this genetic test will have a direct impact on this patient’s treatment and management.
Information on Tuberous Sclerosis Complex (TSC) and genetic testing:
Tuberous sclerosis complex (TSC) is characterized by abnormalities of the skin, brain, kidney, heart, and lungs.
Skin findings are present in nearly all patients with TSC, and major criteria in skin include facial angiofibromas,
forehead plaque, nontraumatic ungual or periungual fibromas, three or more hypomelanotic macules, or a shagreen
patch. Major features involving other body systems include multiple retinal nodular hamartomas, cortical tuber,
subependymal nodule, subependymal giant cell astrocytoma, cardiac rhabdomyoma, lymphangiomyomatosis, and
renal angiomyolipoma. Individuals with TSC have a significantly increased risk for other neurodevelopmental
disorders. Approximately 50% have intellectual disability or developmental delay and 40% have autism spectrum
disorders. Additionally, greater than 80% have seizures, including infantile spasms with hypsarrhythmia.
Mutations in the TSC1 and TSC2 genes are known to cause TSC. Knowledge of the genetic etiology of TSC may guide
selection of the most appropriate treatment options in some cases. A number of medications are used in the
treatment of TSC.
Clinical Utility of Tuberous Sclerosis Complex (TSC) Genetic Testing
 The specific type and etiology of seizures may influence the selection of medication for each patient. For
example:
o Certain medications may be more effective for infantile spasms and are therefore first choices for
patients with spasms
o Vigabatrin is the treatment therapy for infantile spasms in patients with mutations in TSC1, TSC2
 Some medications may be contraindicated for patients with a specific electroclinical or genetic diagnosis.
Further examples
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o
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Valproic acid should be avoided for epilepsy patients with POLG mutations
Phenytoin, carbamazepine, and lamotrigine should be avoided for epilepsy patients with SCN1A
mutations
o Channel blockers and GABAergic drugs should be avoided for epilepsy patients with CSTB mutations
Proper TSC diagnosis will help the physician in managing the patient more efficiently, while limiting doctor
visits and insurance claims
A specific genetic diagnosis of TSC will allow for family members to be tested for the specific mutation for a
drastically lower cost
Thank you for your review and consideration. I hope you will support this request for genetic testing coverage for
[PATIENT_FIRST_NAME] [PATIENT_LAST_NAME]. If you have questions, or if I can be of further assistance, please do
not hesitate to call me at [PHYSICIAN_PHONE_NUMBER].
Sincerely,
[PHYSICIAN_FIRST_NAME] [PHYSICIAN_LAST_NAME], MD
cc: [PATIENT_FIRST_NAME] [PATIENT_LAST_NAME]
References:
1. Roach and Sparagano (2004) J Child Neurol 19:643-649.