Abnormalities of somatosensory evoked potentials in konzo--an upper motor neuron disorder.
OBJECTIVE
To determine whether the somatosensory pathways are involved or not in konzo.


METHODS
In 1998, 21 konzo subjects (15 females and 6 males; mean age 21 years) underwent a SEP study with a two-channel-equipment (Medtronic Keypoint, Denmark) whereas in 2000, 15 subjects (7 females and 8 males; mean age 21 years) participated in a study with a 4-channel-equipment.


RESULTS
Most subjects (19/21 in 1998 and 12/15 in 2000) showed normal median SEPs. The remainders had no median cortical responses. All 21 subjects in 1998 and 9 out of 15 in 2000 showed abnormalities of tibial SEPs mainly consisting of absence of cortical responses, prolonged cortical latencies, and central sensory delay to the lumbar spine. Most subjects showed normal absolute latencies both at peripheral and spinal levels. The SEP findings did not correlate with the severity, neither the duration of konzo, nor the experience or not of sensory symptoms at the onset of the disease.


CONCLUSIONS
Our findings are not specific of konzo. However, they suggest involvement of intracranial somatosensory pathways and point to similarities with other motor neuron diseases.
Tshala-Katumbay
D
D
Department of Neurology, University Hospital, Kinshasa, Congo.
Edebol Eeg-Olofsson
K
K
Kazadi-Kayembe
T
T
Fällmar
Peo
P
Tylleskär
Thorkild
T
Kayembe-Kalula
T
T
D000293:Adolescent; D000328:Adult; D002648:Child; D004558:Electric Stimulation; D004569:Electroencephalography; D004576:Electromyography; D005073:Evoked Potentials, Somatosensory / Q000502:physiology*; D005260:Female; D007839:Functional Laterality / Q000502:physiology; D006801:Humans; D008297:Male; D008475:Median Nerve / Q000502:physiology; D008875:Middle Aged; D016472:Motor Neuron Disease / Q000503:physiopathology*; D009431:Neural Conduction / Q000502:physiology; D013979:Tibial Nerve / Q000502:physiology