weeks. There is no recurrence. Symptomatic
treatment in the form of liquid paraffin for external applications
and oral antihistaminics are sufficient.
Hansen's disease: Hansen's disease
is a chronic, mildly contagious, primarily involving the
peripheral nerves, secondarily involving the skin, the mucous
membrane! of upper respiratory tract, eyes, bone, testes,
reticulo-endothelial system and other organs except brains,
spinal cord, gall bladder and ovaries. Infection is disseminated
through the blood stream and lymphatics. The Schwann cells
act as biological refrigerators and organism remains alive
within Schwann cells for years together.
In 1960, the mycobacteria leprae were grown
in the foot pads of mice. It was seen that human beings are
the only natural hosts. With genetic susceptibility in the
background, the disease spreads through prolonged direct physical
contact, basal secre. tion and breast milk.
Hansen's disease is classified into 5 types
viz., (i) Tuberculoid (ii) Borderline Tuberculoid (iii) True
borderline (iv) Borderline lepromatous and (v) Lepromatous.
(i) Tuberculoid Hansen: Solitary or
2 to 3 erythematous coppery patches with flat or raised edges.
These show loss of pain, temperature, touch from the beginning
of the illness. Peripheral nerves including unnamed cuaneous
nerves are thickened.
(ii) Borderline Hansen: Consists of
multiple, asymmetrical lesions irregular in size and shape
associated with thickening of nerves.
(iii) Lepromatous Hansen: This is
characterised by macules in the early stages, infiltrative
lesions and nodules. All the three types of lesions can occur
in the same individual. They are usually symmetrical and occur
in the cooler areas of the body. The scalp, perineum and axilla
are called immune areas for lepromatous Hansen. Sensory loss
occurs often in the distal parts of the limbs. The skin, usually
of the hand is shiny and oedematous, due to lack of vasomotor
tone. There is stuffiness of the nose and ulceration of the
oral cavity. Chronic iridocyclitis may lead on to loss of
vision. Complications like trophic ulcers due to anaesthesis,
claw hand, wrist or foot drop and facial palsy occur.
According to WHO, single drug therapy is
to be deferred so as to prevent emergence of resistant strains.
In non-lepromatous types, Dapsone 100 mgs/ day, on all 7 days
of a week and rifampicin 600 mgs once a month are administered.
In lepromatous type, Dapsone 100 mgs/ day, Clofazimine (Lampren)
50 mgs/ day or 100 mgs on alternate days and Rifampicin 600
mgs once a month are the treatment of choice. The advantages
of a multiple drug therapy are that such a therapy prevents
the emergence of resistant strains of bacteria, the spread
of infection is checked rapidly as the bacilli are destroyed
in a few months time. 1 capsule of Rifampicin can kill 75
to 80% of the bacilli. Within 3 months time an individual
becomes negative for the bacilli with Rifampicin, while Dapsone
takes 2 years. Also the duration of treatment can be shortened
remarkably, with only 6 months in non-lapromatous type and
about 2 years or until smear negative with Dapsone. When all
signs have disappeared or when biopsy shows no granuloma in
the dermis, the treatment could be stopped.
BCG vaccine in Hansen's disease :
BCG vaccine administration leads on to a
lepromin positive stage in the individual. When a lepromin
positive individual is exposed to Hansen, he develops the
less harmful types like tuberculoid Hansen while a lepromin
negative individual develops the more harmful borderline or
lepromatous Hansen's disease.