Barium carbonate intoxication: an electrophysiological study

Barium carbonate is an uncommon poisoning agent in India. This whitish coloured powder is available over the shelf from the chemists and is used mainly as a rodenticide (rat poison). We report an unusual case of barium carbonate poisoning. The nerve and muscle electrophysiological studies are reported for the first time in barium carbonate intoxication. A 19 year old boy presented to a hospital emergency department with sudden onset tetraplegia. He was referred to our centre as a case of Guillian-Barre syndrome. The patient presented with tingling in the right upper arm, which was immediately followed by weakness in all four limbs. The weakness progressed and involved trunk muscles also within a few minutes. There was no history suggestive of bulbar or facial nerve involvement. On examination, higher mental functions, cranial nerves, and sensory and cerebellar examination were normal. Examination of the motor system showed a power of 0/5 globally. No deep tendon reflex could be elicited. Surprisingly, with complete areflexic paralysis there was increased tone in the lower limbs. A diagnosis of Guillian-Barre syndrome was considered, but there were some pointers against this diagnosis. The onset and progression to complete tetraplegia was very rapid and the weakness started from the upper limbs followed by that of the lower limbs. Increased tone in the lower limbs was …