Subacute myelo-optic neuropathy

Subacute myelo-optic neuropathy
Synonyms	SMON
Pronounce	N/A
Specialty	N/A
Symptoms	Visual impairment, paralysis, numbness
Complications	Blindness, paraplegia
Onset	Subacute
Duration	Chronic
Types	N/A
Causes	Clioquinol toxicity
Risks	Use of clioquinol
Diagnosis	Clinical evaluation, neurological examination
Differential diagnosis	Multiple sclerosis, neuromyelitis optica
Prevention	N/A
Treatment	Discontinuation of clioquinol, supportive care
Medication	N/A
Prognosis	Variable, can lead to permanent disability
Frequency	Rare, historically significant in Japan
Deaths	N/A

Subacute Myelo-Optic Neuropathy (SMON) is a rare, toxic disorder that was prevalent in Japan during the 1960s and 1970s. The disease is characterized by subacute onset of sensory and motor disturbances in the lower limbs, visual impairment, and, in some cases, bowel and bladder dysfunction.

Epidemiology

SMON was first recognized in Japan in the 1960s, where it reached epidemic proportions. The disease affected over 10,000 people in Japan before its cause was identified as the drug clioquinol. After the drug was withdrawn from the market, the incidence of SMON dropped dramatically.

Symptoms

The symptoms of SMON include sensory and motor disturbances in the lower limbs, visual impairment, and, in some cases, bowel and bladder dysfunction. The onset of symptoms is usually subacute, occurring over a period of days to weeks.

Cause

The cause of SMON was identified as the drug clioquinol, an antifungal and antiprotozoal medication. Clioquinol was widely used in Japan to treat various intestinal infections. However, it was found to be neurotoxic, leading to the development of SMON in some individuals.

Treatment

Treatment for SMON is primarily supportive, as there is no cure for the disease. Management of symptoms may include physical therapy for motor disturbances, visual aids for visual impairment, and medications to manage bowel and bladder dysfunction.

See also

• Neuropathy
• Clioquinol
• Epidemiology