The influence of isolated small nerve fibre dysfunction on microvascular control in patients with diabetes mellitus.
OBJECTIVE
The aim of the study was to investigate the influence of isolated small nerve fibre dysfunction on microvascular skin blood flow and transcutaneous oxygen tension in patients with diabetes mellitus.


METHODS
Small nerve fibre dysfunction was assessed by the measurement of thermal and pain perception thresholds. Patients with evidence of large fibre disturbances as evaluated by means of vibration perception threshold were excluded from the study. Microvascular blood flow was investigated with laser-Doppler-fluxmetry (LDF) following stimulation with acetylcholine and mild thermal injury.


RESULTS
Diabetic patients with small nerve fibre injury showed a significantly reduced increase in the laser-Doppler-flux signal following the application of acetylcholine compared with patients without neuropathy or healthy control subjects (2.8 arbitrary units (AU) (1.3-5.5) vs. 7.2 AU (4.1-25.5); P = 0.007 and vs. 8.5 AU (3.0-17.0), P = 0.02, respectively). The increase in LDF following thermal injury was also diminished in patients with small nerve fibre dysfunction compared with patients without neuropathy or the control group (29.8 AU (17.2-46.5) vs. 51.2 AU (29.5-93.5); P = 0.02 and vs. 54.6 AU (39.7-97.7); P = 0.004, respectively). In addition, they showed a significantly reduced transcutaneous oxygen tension compared with the other groups (42.9 mmHg (41.6-55.5) vs. 56.1 mmHg (49.2-60.8); P = 0.04 and vs. 59.0 mmHg (54.6-80.3), P = 0.03, respectively).


CONCLUSIONS
Our study confirms an association between small nerve fibre injury and skin microvascular dysfunction. It further underlines the concept of neurovascular disturbances in the pathogenesis of neurotrophic foot ulceration. Diabet. Med. 18, 489-494 (2001)
Pfützner
A
A
Department of Endocrinology and Metabolism, University of Mainz, Haydnstrasse 10, D-55130 Mainz, Germany.
Forst
T
T
Engelbach
M
M
Margin
T
T
Goitom
K
K
Löbig
M
M
Beyer
J
J
Kunt
T
T
D000109:Acetylcholine / Q000494:pharmacology; D000328:Adult; D001783:Blood Flow Velocity; D003929:Diabetic Neuropathies / Q000503:physiopathology*; D003930:Diabetic Retinopathy / Q000503:physiopathology; D005260:Female; D005858:Germany; D006358:Hot Temperature; D006801:Humans; D017078:Laser-Doppler Flowmetry; D008297:Male; D008833:Microcirculation / Q000187:drug effects / Q000294:innervation / Q000503:physiopathology*; D008875:Middle Aged; D009412:Nerve Fibers / Q000502:physiology*; D009460:Neurologic Examination; D012016:Reference Values; D012039:Regional Blood Flow / Q000187:drug effects; D044465:White People
D000109:Acetylcholine