Question

What is the etiological agent of cutaneous leishmaniasis? How is the disease transmitted and what are its typical manifestations?

Answer 1

Leishmaniasis is a parasitic disease caused by the Leishmania parasite. This parasite typically lives in infected sand flies. The sand flies that carry the parasite typically reside in tropical and subtropical environments. Fatal epidemics have occurred in areas of Asia, East Africa, and South America.

Leishmaniasis comes in three forms: cutaneous, visceral, and mucocutaneous. Different species of the Leishmania parasite are associated with each form. The parasite lives and multiplies inside the female sand fly. This insect is most active in humid environments during the warmer months and at night, from dusk to dawn. Domestic animals, such as dogs, can serve as reservoirs for the parasite. Transmission may occur from animal to sand fly to human.

Cutaneous leishmaniasis

Cutaneous leishmaniasis causes ulcers on your skin. It’s the most common form of leishmaniasis. Treatment may not always be necessary depending on the person, but it can speed healing and prevent complications.

Mucocutaneous leishmaniasis

A rare form of the disease, mucocutaneous leishmaniasis is caused by the cutaneous form of the parasite and can occur several months after skin ulcers heal.

With this type of leishmaniasis, the parasites spread to your nose, throat, and mouth. This can lead to partial or complete destruction of the mucous membranes in those areas.

Although mucocutaneous leishmaniasis is usually considered a subset of cutaneous leishmaniasis, it’s more serious. It doesn’t heal on its own and always requires treatment.

Visceral leishmaniasis

Visceral leishmaniasis is sometimes known as systemic leishmaniasis or kala azar.

It usually occurs two to eight months after being bitten by a sand fly. It damages internal organs, such as your spleen and liver. It also affects bone marrow, as well as immune system through damage to these organs. The condition is almost always fatal if it’s not treated.

Symptoms depend on the form of the disease.

Cutaneous leishmaniasis

The main symptom of this condition is painless skin ulcers. Cutaneous symptoms may appear a few weeks after being bitten by an infected sand fly. However, sometimes symptoms won’t appear for months or years.

Mucocutaneous leishmaniasis

In people with the mucocutaneous form of the disease, symptoms usually appear one to five years after the skin lesions. These are primarily ulcers in their mouth and nose or on their lips.

Other symptoms may include:

• runny or stuffy nose
• nosebleeds
• difficulty breathing

Visceral leishmaniasis

Symptoms often don’t appear for months after the bite with this type of leishmaniasis. Most cases are apparent two to six months after the infection occurred. Common signs and symptoms include:

• weight loss
• weakness
• fever that lasts for weeks or months
• enlarged spleen
• enlarged liver
• decreased production of blood cells
• bleeding
• other infections
• swollen lymph nodes