Abstract
Guillain-Barré syndrome (GBS) is classified into acute inflammatory demyelinating
polyneuropathy (AIDP), acute motor axonal polyneuropathy (AMAN), and acute motor sensory
axonal polyneuropathy (AMSAN), but little is known about the incidence of the subtypes
and electrophysiologic changes in Northwest of Iran. The aim of this study is to present
the electrophysiologic pattern and incidence of various subtypes of childhood GBS.
Electrophysiologic features of 72 children (aged 1–15 years old) were studied prospectively
during two years in Tabriz Children Hospital. Electrodiagnostic tests were performed
in the first 2 weeks of the disease onset. Motor nerve conduction study was performed
on the tibial, peroneal, median, and ulnar nerves. Sensory nerve conduction study
was performed on the median and sural nerves, F-waves were also studied on the tibial,
median, and ulnar nerves. Compound muscle action potential (CMAP) and sensory nerve
action potential (SNAP) amplitudes, distal latencies, nerve conduction velocities
and F-wave latencies were measured. In this concern, any conduction block and temporal
dispersion were noted. Needle electromyography was performed, motor unit action potential
changes, and spontaneous activity were studied. Patients were classified into AIDP,
AMAN, and AMSAN on the basis of electrodiagnostic criteria. About half of the patients
(47.2%) had AIDP form, 44.4% had AMAN, and 5.6% had AMSAN. Moreover, Fisher variant
was observed in 2.8% of the cases. The most common electrophysiologic findings were
low amplitude CMAP and abnormal F- waves, i.e. 97.2% and 88.9% respectively. Twelve
patients (16.8%) required assisted ventilation, 75% of them had AMAN form of GBS.
AMAN form of childhood GBS is relatively common in Iran in comparison to Western countries.
Respiratory failure resulting in mechanical ventilation is more probable in this form.
Keywords
Electrophysiologic tests - Guillain-Barré syndrome - subtypes - children
