Abstract
BACKGROUND
Sural sparing defined as absent/abnormal median sensory nerve action potential (SNAP) amplitude or absent/abnormal ulnar SNAP amplitude with a normal sural SNAP amplitude is thought to be a marker for inflammatory demyelinating polyneuropathies.
OBJECTIVE
If sural sparing pattern specifically defined as absent/abnormal median and ulnar SNAP amplitude with normal sural SNAP amplitude (AMUNS) is sensitive and specific when compared with either absent/abnormal median and normal sural (AMNS) or absent/abnormal ulnar and normal sural (AUNS) for acute inflammatory demyelinating polyneuropathy (AIDP), chronic inflammatory demyelinating polyneuropathy (CIDP), select non-diabetic axonopathies (AXPs), and diabetic neuropathies (DNs).
METHOD
Retrospective analysis from 2001 to 2010 on all newly diagnosed AIDP, CIDP, select non-diabetic AXP, and DN.
RESULTS
There were 20 AIDP and 23 CIDP. Twenty AXP and 50 DN patients between 2009 and 2010 were included as controls. AMUNS was seen in 65% of AIDP, 39% CIDP compared with 10% of AXP and 6% for DN with sensitivity of 51%, specificity of 92%, whereas the specificity of AMNS/AUNS was 73% and its sensitivity was 58%. If a patient has AMUNS they are >12 times more likely to have AIDP (p < 0.001).
CONCLUSION
Sural sparing is highly specific but not sensitive when compared with either AMNS or AUNS in AIDP but does not add to sensitivity or specificity in CIDP.
TY - JOUR
T1 - Role of "Sural Sparing" Pattern (Absent/Abnormal Median and Ulnar with Present Sural SNAP) Compared to Absent/Abnormal Median or Ulnar with Normal Sural SNAP in Acute Inflammatory Demyelinating Polyneuropathy.
AU - Surpur,Spurthi Sunil,
AU - Govindarajan,Raghav,
Y1 - 2017/09/29/
PY - 2017/07/10/received
PY - 2017/09/13/accepted
PY - 2017/11/1/entrez
PY - 2017/11/1/pubmed
PY - 2017/11/1/medline
KW - acute inflammatory demyelinating polyneuropathy
KW - axonopathy
KW - chronic inflammatory demyelinating polyneuropathy
KW - diabetic neuropathy
KW - sural sparing
SP - 512
EP - 512
JF - Frontiers in neurology
JO - Front Neurol
VL - 8
N2 - BACKGROUND: Sural sparing defined as absent/abnormal median sensory nerve action potential (SNAP) amplitude or absent/abnormal ulnar SNAP amplitude with a normal sural SNAP amplitude is thought to be a marker for inflammatory demyelinating polyneuropathies. OBJECTIVE: If sural sparing pattern specifically defined as absent/abnormal median and ulnar SNAP amplitude with normal sural SNAP amplitude (AMUNS) is sensitive and specific when compared with either absent/abnormal median and normal sural (AMNS) or absent/abnormal ulnar and normal sural (AUNS) for acute inflammatory demyelinating polyneuropathy (AIDP), chronic inflammatory demyelinating polyneuropathy (CIDP), select non-diabetic axonopathies (AXPs), and diabetic neuropathies (DNs). METHOD: Retrospective analysis from 2001 to 2010 on all newly diagnosed AIDP, CIDP, select non-diabetic AXP, and DN. RESULTS: There were 20 AIDP and 23 CIDP. Twenty AXP and 50 DN patients between 2009 and 2010 were included as controls. AMUNS was seen in 65% of AIDP, 39% CIDP compared with 10% of AXP and 6% for DN with sensitivity of 51%, specificity of 92%, whereas the specificity of AMNS/AUNS was 73% and its sensitivity was 58%. If a patient has AMUNS they are >12 times more likely to have AIDP (p < 0.001). CONCLUSION: Sural sparing is highly specific but not sensitive when compared with either AMNS or AUNS in AIDP but does not add to sensitivity or specificity in CIDP.
SN - 1664-2295
UR - https://www.unboundmedicine.com/medline/citation/29085327/Role_of_"Sural_Sparing"_Pattern__Absent/Abnormal_Median_and_Ulnar_with_Present_Sural_SNAP__Compared_to_Absent/Abnormal_Median_or_Ulnar_with_Normal_Sural_SNAP_in_Acute_Inflammatory_Demyelinating_Polyneuropathy_
DB - PRIME
DP - Unbound Medicine
ER -
