Contribution of QSART to the diagnosis of small fiber neuropathy

Thaisetthawatkul, Pariwat; Filho, J. Americo M. Fernandes; Herrmann, David N.

doi:10.1002/mus.23891

Cited by 87 publications

(68 citation statements)

References 34 publications

Supporting

Mentioning

Contrasting

Unclassified

Order By: Relevance

“…Patients with SFN have normal routine electrophysiological studies, such that confirmation of the diagnosis relies on an abnormality of small fiber measures including intraepidermal fiber density (IENFD) by skin biopsy, quantitative sensory testing (QST) or sudomotor function by quantitative sudomotor axon reflex test (QSART). In our previous study, addition of QSART to a combination of clinical examination, QST and IENFD increased the diagnostic yield of tests for SFN [1]. This study suggested that somatic sensory and QSART evaluations were additive in the assessment of distal SFN, leading to the hypothesis that sensory and autonomic small fiber dysfunctions occur independently and are not highly correlated in the setting of SFN.…”

Section: Introductionmentioning

confidence: 80%

“…Those patients who presented with distal sensory symptoms of pain, without muscle weakness or upper motor neuron signs and had normal nerve conduction studies and electromyography (NCS/EMG), underwent ARS (QSART, cardiovagal and adrenergic testing) with calculation of a composite autonomic severity score (CASS), QST and skin biopsy (IENFD) to assess for SFN. The protocols and procedures employed for the clinical evaluation, electrophysiological studies, QSART, QST and IENFD analysis have been previously described in a study that involved a subset of the current cohort and addressed the contribution of QSART toward diagnostic criteria for SFN [1]. For cooling and vibration thresholds, abnormality was defined as a threshold above the 95th percentile for age, height, weight and gender [1].…”

Section: Methodsmentioning

confidence: 99%

“…The protocols and procedures employed for the clinical evaluation, electrophysiological studies, QSART, QST and IENFD analysis have been previously described in a study that involved a subset of the current cohort and addressed the contribution of QSART toward diagnostic criteria for SFN [1]. For cooling and vibration thresholds, abnormality was defined as a threshold above the 95th percentile for age, height, weight and gender [1]. Heat pain threshold abnormality was defined as a value below the 5th percentile (hyperalgesia) or above the 95th percentile (hypoalgesia) [1].…”

Section: Methodsmentioning

confidence: 99%

“…For cooling and vibration thresholds, abnormality was defined as a threshold above the 95th percentile for age, height, weight and gender [1]. Heat pain threshold abnormality was defined as a value below the 5th percentile (hyperalgesia) or above the 95th percentile (hypoalgesia) [1]. A value below the 5th percentile was considered as an abnormal QSART volume or IENFD as previously described [1].…”

Section: Methodsmentioning

confidence: 99%

See 3 more Smart Citations

Autonomic evaluation is independent of somatic evaluation for small fiber neuropathy

Thaisetthawatkul

Filho

Herrmann

2014

Journal of the Neurological Sciences

Self Cite

View full text Add to dashboard Cite

Section: Introductionmentioning

confidence: 80%

Section: Methodsmentioning

confidence: 99%

Section: Methodsmentioning

confidence: 99%

Section: Methodsmentioning

confidence: 99%

See 2 more Smart Citations

Autonomic evaluation is independent of somatic evaluation for small fiber neuropathy

Thaisetthawatkul

Filho

Herrmann

2014

Journal of the Neurological Sciences

Self Cite

View full text Add to dashboard Cite

“…Sudomotor function tests provide information on peripheral autonomic function. In specialist centers, they are currently used as adjuvant or screening tests for DSPN [73]. The quantitative sudomotor axon reflex test (QSART) [74][75] and the commercially available Q-Sweat [76] have been in clinical application for more than a decade.…”

Section: Methods For Assessment Of Small Fiber Neuropathymentioning

confidence: 99%

Distal Sensorimotor Neuropathy: Improvements in Diagnosis

2015

View full text Add to dashboard Cite

■ AbstractNeurological complications of diabetes are common, affecting up to 50% of people with diabetes. In these patients, diabetic sensorimotor neuropathy (DSPN) is by far the most frequent complication. Detecting DSPN has traditionally been a clinical exercise that is based on signs and symptoms. However, the appearance of morphometric and neurophysiological techniques along with composite scoring systems and new screening tools has induced a paradigm change in the detection and stratification of DSPN and our understanding of its natural history and etiopathogenesis. These newer techniques have provided further evidence that changes in small nerve fiber structure and function precede large fiber changes in diabetes. Although useful, the challenge for the use of these new techniques will be their sensitivity and specificity when widely adopted and ultimately, their ability to demonstrate improvement when pathogenic mechanisms are corrected. Concurrently, we have also witnessed an emergence of simpler screening tools or methods that are mainly aimed at quicker detection of large fiber neuropathy in the outpatient setting. In this review, we have focused on techniques and tools that receive particular attention in the current literature, their use in research and potential use in the clinical environment.Keywords: diabetic neuropathy · small fiber neuropathy · axon reflex test · nerve conduction · nerve fiber density · laser Doppler imager flare · corneal confocal microscopy · electromyography · sudomotor function

show abstract

Scientific Advances in and Clinical Approaches to Small-Fiber Polyneuropathy

2019

View full text Add to dashboard Cite

IMPORTANCE Small-fiber polyneuropathy involves preferential damage to the thinly myelinated A-delta fibers, unmyelinated C sensory fibers, or autonomic or trophic fibers. Although this condition is common, most patients still remain undiagnosed and untreated because of lagging medical and public awareness of research advances. Chronic bilateral neuropathic pain, fatigue, and nausea are cardinal symptoms that can cause disability and dependence, including pain medication dependence.OBSERVATIONS Biomarker confirmation is recommended, given the nonspecificity of symptoms. The standard test involves measuring epidermal neurite density within a 3-mm protein gene product 9.5 (PGP9.5)-immunolabeled lower-leg skin biopsy. Biopsies and autonomic function testing confirm that small-fiber neuropathy not uncommonly affects otherwise healthy children and young adults, in whom it is often associated with inflammation or dysimmunity. A recent meta-analysis concluded that small-fiber neuropathy underlies 49% of illnesses labeled as fibromyalgia. Initially, patients with idiopathic small-fiber disorders should be screened by medical history and blood tests for potentially treatable causes, which are identifiable in one-third to one-half of patients. Then, secondary genetic testing is particularly important for familial and childhood cases. Treatable genetic causes include Fabry disease, transthyretin and primary systemic amyloidosis, hereditary sensory autonomic neuropathy-1, and ion-channel mutations. Immunohistopathologic evidence suggests that small-fiber dysfunction and denervation, especially of blood vessels, contributes to diverse symptoms, including postexertional malaise, postural orthostatic tachycardia, and functional gastrointestinal distress. Preliminary evidence implicates acute or chronic autoreactivity in some cases, particularly in female patients and otherwise healthy children and young adults. Different temporal patterns akin to Guillain-Barré syndrome and chronic inflammatory demyelinating polyneuropathy have been described; here, corticosteroids and immunoglobulins, which are often efficacious for inflammatory neuropathic conditions, are increasingly considered.CONCLUSIONS AND RELEVANCE Because small fibers normally grow throughout life, improving contributory conditions may permit regrowth, slow progression, and prevent permanent damage. The prognosis is often hopeful for improving quality of life and sometimes for abatement or resolution, particularly in the young and otherwise healthy individuals. Examples include diabetic, infectious, toxic, genetic, and inflammatory causes. The current standard of care requires prompt diagnosis and treatment, particularly in children and young adults, to restore life trajectory. Consensus diagnostic and tracking metrics should be established to facilitate treatment trials.

show abstract

Contribution of QSART to the diagnosis of small fiber neuropathy

Abstract: Assessment of both somatic and peripheral autonomic small nerve fibers enhances diagnostic criteria for SFN.

Cited by 87 publications

References 34 publications

Autonomic evaluation is independent of somatic evaluation for small fiber neuropathy

Autonomic evaluation is independent of somatic evaluation for small fiber neuropathy

Distal Sensorimotor Neuropathy: Improvements in Diagnosis

Scientific Advances in and Clinical Approaches to Small-Fiber Polyneuropathy

Contact Info

Product

Resources

About