Small Fiber Neuropathy (SFN)

Small fiber neuropathy (SFN) results in neuropathic pain that is often described as burning, tingling, or stabbing and typically begins in the distal extremities. Pain is often associated with autonomic symptoms such as orthostatic dizziness, palpitations, dry eyes, and dry mouth. Some individuals report that episodes are triggered by heat or exercise. The onset is typically in adulthood. Individuals with SFN have thinly myelinated and unmyelinated small diameter nerve fibers, and the clinical diagnosis is confirmed by demonstrating reduced intraepidermal nerve fiber density (IENFD) and/or abnormal quantitative sensory testing (QST) in the presence of normal nerve conduction studies.

Tests Available

Forms and Documents

Test Details

SCN9A
  • Confirmation of a clinical diagnosis
  • To differentiate SCN9A-related pain disorders from other genetic or environmental causes of pain
  • Carrier testing for individuals with a known familial SCN9A mutation
  • Prenatal diagnosis in at-risk pregnancies
  • Capillary Sequencing

Ordering

650
6-7 weeks
2-5 mL Blood - Lavender Top Tube
Oral Rinse (30-40 mL) | Buccal Swabs

Billing

81479x1
No
Yes
* For price inquiries please email zebras@genedx.com

References

  1. Fertleman et al., (2006) Neuron 52;767- 774.
  2. Faber et al., (2012) Ann Neurol 71 :26-39.
  3. Goldberg et al., (2007) Clin Genet 71:311-319.
  4. Dabby R., (2012) Curr Neurol Neurosci Rep 12 :76-83.
  5. Fischer, T.Z. and Waxman, S.G., (2010) Ann NY Acad Sci 1184:196-207.
  6. Dib-Hajj et al., (2008) Adv in Genet 63:85-110.
  7. Drenth et al., (2005) J Invest Dermatol 124:1233-1238.

Forms and Documents

Test Details

AARS, AIFM1, ATL1, ATP7A, BSCL2, DNAJB2, DNM2, DNMT1, DYNC1H1, EGR2, FGD4, FIG4, GAN, GARS, GDAP1, GJB1, GLA, GNB4, HARS, HINT1, HSPB1, HSPB8, IGHMBP2, IKBKAP, INF2, KIF1A, KIF5A, LITAF, LMNA, LRSAM1, MFN2, MME, MORC2, MPZ, MTMR2, NDRG1, NEFL, NGF, NTRK1, PLEKHG5, PMP22, PRDM12, PRPS1, PRX, RAB7A, REEP1, RETREG1, SBF1, SBF2, SCN11A, SCN9A, SEPT9, SH3TC2, SLC12A6, SLC52A2, SLC52A3, SPTLC1, SPTLC2, TFG, TRIM2, TRPV4, TTR, WNK1, YARS
  • Molecular confirmation of a clinical diagnosis
  • To assist with decisions about treatment and management of individuals with neuropathy
  • Testing of at-risk relatives for specific known mutation(s) previously identified in an affected family member
  • Prenatal diagnosis for known familial mutation(s) in at-risk pregnancies
  • Next-Gen Sequencing
  • Deletion/Duplication Analysis

Ordering

737
4 weeks
2-5 mL Blood - Lavender Top Tube
Oral Rinse (30-40 mL) | Buccal Swabs

Billing

81260X1, 81324X1, 81325X1, 81403x1, 81404x4, 81405x2, 81406x2
Yes
Yes
* For price inquiries please email zebras@genedx.com

Forms and Documents

Test Details

ATL1, DNMT1, IKBKAP, KIF1A, NGF, NTRK1, PRDM12, RAB7A, RETREG1, SCN11A, SCN9A, SPTLC1, SPTLC2, WNK1
  • Molecular confirmation of a clinical diagnosis
  • To assist with decisions about treatment and management of individuals with neuropathy
  • Testing of at-risk relatives for specific mutation(s) previously identified in an affected family member
  • Prenatal diagnosis for known familial mutation(s) in at-risk pregnancies
  • Next-Gen Sequencing
  • Deletion/Duplication Analysis

Ordering

T399
4 weeks
2-5 mL Blood - Lavender Top Tube
Oral Rinse (30-40 mL) | Buccal Swabs

Billing

81405x1, 81406x1, 81479x1
No
Yes
* For price inquiries please email zebras@genedx.com