Question

“Like a polio ward from the 1950s” is how Guy McKhann, M.D., a neurology specialist at John Hopkins School of Medicine, describes a ward of Beijing Hospital that he visited on a trip to China in 1986. Dozens of paralyzed children---some attached to respirators to assist their breathing--filled the ward to overflowing. The chinese doctors thought the children had Guillain-Barre syndrome (GBS), a rare paralytic condition, but Dr. McKhann wasn’t convinced. There were simply too many stricken children for the illness to be the rate Guillain-Barre syndrome. Was it polio--as some of the Beijing staff feared? Or was it another illness, perhaps one that had not yet been discovered? Guillain-Barre syndrome is a relatively rare paralytic condition that strikes after a viral infection or an immunization. There is no cure, but usually the paralysis slowly disappears, and lost sensation slowly returns as the body repairs itself. In classic Guillain-Barre, patients can neither feel sensations nor move their muscles.

Is the paralytic illness that affected the chinese children a demyelinating condition? Why or why not?

Answer 1

Demyelinating condition is characterised by loss of myelin sheath which insulates axon and is also responsible for faster conduction of nerve impulse. Guillain Barre syndrome is a demyelinating condition which shows ascending paralysis from lower limbs towards chest or upper limbs.

Whenever there is myelin loss, both sensory and motor functions are affected.

In this case, both sensory and motor functions are affected, but there is no history of nerve conduction tests.

Demyelinating condition is confirm by nerve conduction tests which shows decreased speed of conduction.

Nerve conduction tests also shows the strength of action potential and thus neuronal activity.