[Subclinical lead neuropathy].
OBJECTIVE
The electrophysiological assessment of peripheral nervous system in asymptomatic workers chronically exposed to inorganic Pb.


METHODS
41 asymptomatic workers (group A and B) and 35 healthy subjects (group C) were included in study. Motor (radial, peroneal), and sensory (radial, sural) nerves conduction studies, EMG from Extensor Digitorum Communis (EDC) muscle, and skin sympathetic response (SSR) were performed. The level of free erythrocyte protoporphyrins (FEP) was measured in workers. The value of 100 microg/100 ml of erythrocytes was the borderline between these without (A) and those with (B) biochemical signs of Pb loading. Age and duration of occupational exposure did not differ between 2 groups of workers.


RESULTS
In motor conduction studies only amplitude of muscle action potential from radial nerve in group B was significantly lower when compared with controls. Parameters describing sensory studies did not differ significantly among 3 groups. In both groups of workers EMG revealed neurogenic changes in EDC muscle, and duration of motor unit potential was correlated with FEP's level. The amplitude of SSR was in both groups of workers significantly lower in comparison with results obtained in controls. Moreover, there was a negative correlation between amplitude of SSR obtained from hand with FEP's level.


CONCLUSIONS
In asymptomatic workers chronically exposed to inorganic PB the subclinical damage of peripheral nervous system involving neurogenic changes on EMG and abnormal SSR was recorded.
Bilińska
Małgorzata
M
Katedra i Klinika Neurologii AM we Wrocławiu.
Brzezowska
Dorota
D
Koszewicz
Magdalena
M
Antonowicz-Juchniewicz
Jolanta
J
Modrzycka
Teresa
T
D000328:Adult; D004185:Disability Evaluation; D004576:Electromyography / Q000295:instrumentation; D005260:Female; D006801:Humans; D007855:Lead Poisoning / Q000150:complications*; D008297:Male; D008875:Middle Aged; D009784:Occupational Diseases / Q000097:blood / Q000209:etiology / Q000503:physiopathology; D016273:Occupational Exposure / Q000009:adverse effects; D010523:Peripheral Nervous System Diseases / Q000097:blood* / Q000209:etiology* / Q000503:physiopathology; D012720:Severity of Illness Index