Sean Klepper M.D.
Artur Zembowicz M.D....
- Group of protozoal infestations prevalent in Latin America, Africa, Asia and the Mediterranean
- Various clinical forms exist, including cutaneous, mucocutaneous and visceral leishmaniasis, with different species responsible for the various presentations.
- Dogs, cats and rodents serve as reservoirs, and the vector is the sandfly.
- Cutaneous lesions show infiltrates of histiocytes containing groups of the organism within the dermis.
- The intracellular leishmanial amastigotes range from 1 to 3 μm in diameter and contain a round nucleus and adjacent transverse bar-like kinetoplast (sometimes difficult to visualize).
- The kinetoplast is a useful feature in distinguishing leishmaniasis from histoplasmosis, which also shows multiple small organisms within hitiocytes.
- Giemsa stains the nucleus purple and the kinetoplast bright red or red-purple.
- Ulceration with peripheral pseudoepitheliomatous hyperplasia may occur.
- If organisms cannot be identified histologically, the diagnosis can be made using culture or PCR, with PCR having greater sensitivity.