Small-fiber Neuropathy in Chronic Kidney Disease
Small-fiber Neuropathy in Chronic Kidney Disease
Neurological dysfunction is a common complication of late stage chronic kidney disease (CKD)
 and peripheral nerve system is often involved in such complication. Sensory disturbances such
 as paresthesia and hypoesthesia are the predominant symptoms in uremic polyneuropathy and it
 is traditionally thought the uremic polyneuropathy mainly involve large-diameter sensory
 nerves. However in uremic patients the abnormal thermal thresholds, the sensory symptoms like
 numbness, burning, paradoxical heat, cold or freezing, and pain, and the frequent symptoms of
 autonomic dysfunction suggest that small-fiber neuropathy should be a clinical entity in
 patients of CKD. But there are still few investigations with emphasis on the changes of
 small-fiber nerves in CKD, and little is known about the characteristics and mechanism of
 small-fiber neuropathy in CKD. Skin biopsy with evaluation of epidermal nerve density and the
 morphology of epidermal nerves and the subepidermal nerve plexus is an effective and
 minimally invasive test for assessment of small-fiber neuropathy. Contact heat evoked
 potential (CHEP) recording the brain responses evoked by contact heat stimuli on the skin is
 a non-invasive technique to investigate the thermo-nociceptive pathways mediated by
 small-fiber nerves. In the current study, we will use an integrated approach by combining the
 skin biopsy, quantitative sensory testing, autonomic function tests, and CHEP to investigate
 the pathological, psychophysical and physiological aspects of small-fiber neuropathy in
 patients of CKD. The aims of the current study is to address the following issues: (1) the
 changes of small fiber nerves in uremia and CKD of different stage; (2) the correlation of
 skin innervation with clinical manifestations, thermal thresholds, and autonomic function;
 (3) the influence of dialysis therapy, the type of dialysis therapy, or renal transplantation
 on the small fiber neuropathy in uremia; (4) the roles of blood chemical substances, metals,
 and endocrine profiles on the development of small-fiber neuropathy; (5) the relationship
 between the small-fiber neuropathy and pruritus or restless leg syndrome; and (6) the
 pathological and physiological correlates of painful symptoms by skin biopsy and CHEP in CKD
 related neuropathy. The results of the study will provide important insights in the
 understanding of the pathogenesis, and the prevention and new treatments of small-fiber
 neuropathy in CKD.
Inclusion Criteria:

 -  The patients should fulfill the criteria of CKD according to renal function study and
 the patients of end-stage renal disease should receive regular dialysis therapy and
 follow-up at outpatient clinics.

 -  For disease comparison, patients with peripheral neuropathy of variable etiologies
 will also be recruited.

 Exclusion Criteria:

 -  Poor control DM,

 -  Severe heart failure,

 -  Bleeding tendency,

 -  Severe lung disease with respiratory distress,

 -  Severe infection,

 -  Alcoholism,

 -  Amyloidosis,

 -  Poor wound healing history.