Demyelinating Neuropathy of the 1a Afferent Nerve Fibers

Case Report

Austin J Clin Neurol 2017; 4(3): 1109.

Demyelinating Neuropathy of the 1a Afferent Nerve Fibers

Partanen J1* and Auranen M2

1Department of Clinical Neurophysiology, University of Helsinki, Finland

2Department of Neurology, University of Helsinki, Finland

*Corresponding author: Juhani Partanen, Department of Clinical Neurophysiology, University of Helsinki, Jorvi Hospital, P.O. Box 80000029 HUS, Helsinki, Finland

Received: April 12, 2017; Accepted: May 19, 2017; Published: May 29, 2017


We describe a female patient with a selective demyelinating disease of the 1a afferent sensory nerve fibers. After suffering from fever for 3 days the patient developed disorder of balance, dizziness, muscle cramps and altered sense of position and muscle tension of the trunk and extremities. Neurological examination revealed positive Romberg´s sign with no improvement during follow-up of 8 years. Laboratory and imaging studies showed no remarkable findings. However, ENMG demonstrated a permanent slow conduction affecting selectively the 1a afferent nerve fibers. We conclude that the patient suffered from an acute and probably immune-mediated demyelinating disease restricted to 1a-afferent nerve fibers, with a prompt remission but persistent sequelae.

Keywords: Dysimmune neuropathy; Guillain-Barré syndrome; Nerve conduction velocity; 1a afferents; Muscle spindle; Muscle cramps


Polyneuropathy means dysfunction of the peripheral nerves. There are several types of polyneuropathies: axonal, demyelinating [1] and those associated with metabolic changes [2]. Polyneuropathy may selectively affect either heavily myelinated Aα and Aβ nerve fibers or thin Aδ and C nerve fibers [3], or be restricted to either motor or sensory nerve fibers [4]. It is thus essential to investigate the possible alteration in every nerve fiber group (Figure 1). We describe a patient who suffered from a selective demyelination of 1a-afferent Aα nerve fibers.