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Leprosy Reactions

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HealthWiki > Disabled Village Children > Chapter 26: Leprosy: Hansen’s Disease > Leprosy Reactions

Sometimes persons with leprosy have sudden periods of increased problems. These may be something like an allergic reaction to the leprosy bacilli. Leprosy reactions can happen in untreated persons, during treatment, or after treatment has stopped. Reactions can occur when there are changes in the body, such as puberty in boys, in late pregnancy or following childbirth, during illness from other causes, after vaccination, or at times of emotional stress.

There are 2 types of leprosy reactions:

Type 1 reactions happen in persons with borderline leprosy when the body increases its fight against the leprosy germs. There is danger of new weakness and loss of feeling.

IMPORTANT! Reactions sometimes cause new weakness and loss of feeling without nerve pain.

Signs to watch for are:

  • skin patches may become swollen and red
  • swollen hands and feet
  • new tingling or weakness of hands and feet
  • pain or discomfort along nerves (Rarely, lumps along the nerves form sores and drain pus.)
An arm with swollen skin patches
a normal eye
redness around iris
an eye with a deformed pupil and redness around iris
pupil small, often irregular
severe pain
Pain may begin suddenly or gradually. The eye waters a lot. It hurts more in bright light. There is no pus as with conjunctivitis. Vision is usually blurred. This is a medical emergency. Antibiotic ointments do not help. Get medical help.

Type 2 reactions happen with lepromatous leprosy. The body is reacting against too many bacilli.

Signs may include:

  • swollen, reddish, or dark lumps under the skin, especially on the face, arms, and legs
  • fever
  • pain in testicles, breasts, or fingers
  • stuffiness or bleeding of the nose
  • red eye, with or without pain.

DANGER! This may lead to iritis or loss of vision unless treated early.

Rarely, this reaction causes death due to swelling of the mouth, throat or lungs, or to kidney problems.

If untreated, leprosy reactions can quickly lead to permanent nerve damage with increased paralysis of the hands, feet, or eye muscles, or to permanent damage to the eyes.

Early treatment of leprosy reactions is very important to prevent paralysis, deformity, and blindness.

Treatment of leprosy reaction is discussed in"Treatment and Management of Leprosy".

This page was updated:21 Nov 2019