Hansen’s disease (Leprosy)

Dr Christophe Hsu – dermatologist. Geneva, Switzerland

What is Hansen’s disease?

• It is an infection caused by a bacteria called Mycobacterium Leprae.

How is it transmitted?

• This is still incompletely understood but it would be airborne.
• It is not transmitted during birth and even prolonged contact does not guarantee transmission.

How is it diagnosed?

• Examination of a skin biopsy is the most reliable and based on clinical suspicion.
• Lepromin tests are helpful to classify the type of leprosy but not to confirm the diagnosis.

What does it look like on the skin?

• The disease is classified according to the immunity of the infected person:

1. Tuberculoid (Paucibacillary)(maintained host immunity): lesions tend to be depigmented, few in number with an impaired sensation.

Tuberculoid Leprosy (Hansen

1. Lepromatous (Multibacillary)(depressed host immunity): lesions tend to be more voluminous, many in number and the face can be infiltrated (leonine facies).

Lepromatous Leprosy (Hansen

1. Borderline: lesions less specific in between the Tuberculoid and Borderline types.

Borderline Leprosy (Hansen

• Immunological reactions: sometimes the lesions do not contain the bacilli and are due to the immunity developed by the infected person: erythema nodosum leprosum,  reversion reactions (increased inflammation because of effective treatment, stress, pregnancy…)

Are other organs affected?

• The nervous system and eyes are the most commonly affected:

1. Facial palsy
2. Blindness
3. Claw-hands
4. Foot-drop

• Lower limbs are sometimes amputated due to prolonged bone resorption (osteomyelitis) and skin cancers developing on prolonged ulcers.

How is it treated?

• Treatment regimens vary from country to country.
• Antituberculous drugs, Dapsone and other antibiotics are used. Treatment must be continued for several months or years depending on the type of leprosy.
• Steroids and other anti-inflammatory drugs are used in immunological reactions.

Contributors:

Dr Christophe HSU – dermatologist. Geneva, Switzerland

National Skin Centre. Singapore

Bahasa Indonesia

Español

Português

Tagalog