Leishmania mexicana explained

Leishmania mexicana is a species of obligate intracellular parasites of the protozoan genus Leishmania. In Mexico and Central America, this parasite is the primary cause of cutaneous leishmaniasis.^[1]

Infected sandflies carry L. mexicana in its promastigote form, transmitting it from their salivary glands through their proboscis into the bloodstream of the host. When macrophages phagocytize the parasite, it transitions into its amastigote form, rapidly dividing to break the host cell open and infect other mononuclear phagocytic cells. When uninfected sandflies ingest the blood of an infected animal, they acquire L. mexicana, which returns to the promastigote form to efficiently survive in the insect's midgut.^[2]

Leishmania mexicana can induce the cutaneous and diffuse cutaneous clinical manifestations in humans and certain other mammalian hosts. The cutaneous type develops an ulcer at the bite site, here the amastigotes do not spread and the ulcers become visible either a few days or several months after the initial bite. The diffuse cutaneous type begins when the amastigote diffuses through the skin and metastasize to other tissue. This type does not produce ulcers and there is no treatment.

Treatment of Leishmaniasis caused by L. mexicana consists of pentavalent antimonials as Pentostam or Glucantime injected direct into the ulcer or Intramuscular.

Prevention of L. mexicana infection is principally avoiding the bite of the infected sandfly.

References

• Vinetz JM, Soong L . Leishmania mexicana infection of the eyelid in a traveler to Belize . Braz J Infect Dis . 11 . 1 . 149–52 . February 2007 . 17625744 . 10.1590/s1413-86702007000100030. free .
• Robertson CD, Coombs GH . Multiple high activity cysteine proteases of Leishmania mexicana are encoded by the Imcpb gene array . Microbiology . 140 . Pt 2 . 417–24 . February 1994 . 8180705 . 10.1099/13500872-140-2-417. free .
• Ilg T, Etges R, Overath P, etal . Structure of Leishmania mexicana lipophosphoglycan . J. Biol. Chem. . 267 . 10 . 6834–40 . April 1992 . 10.1016/S0021-9258(19)50502-6 . 1551890 . free .
• Galindo-Sevilla N, Ortiz-Avalos J, Del Angel M, Galvan R, Mancilla-Ramirez J . Leishmania mexicana Strains Isolated from Both Localized Cutaneous (LCL) and Diffuse Cutaneous (DCL) Lesions in Humans Can Produce DCL in Mice, Being Faster in Males . ASM's Annual Meeting on Infectious Diseases: 43rd annual ICAAC Chicago 2003 : 43rd Interscience Conference on Antimicrobial Agents and Chemotherapy . 2003 . American Society for Microbiology . 978-1-55581-284-3.
• 8824958 . 22 . Clinical spectrum of Leishmaniasis . 1996 . Clin Infect Dis . 1–13 . Pearson RD, Sousa AQ . 10.1093/clinids/22.1.1. free .
• Sacks D, Noben-Trauth N . The immunology of susceptibility and resistance to Leishmania major in mice . Nat Rev Immunol . 2 . 11 . 845–58 . 2002 . 10.1038/nri933 . 12415308. free .

Notes and References

1. Majumdar D, Elsayed GA, Buskas T, Boons GJ . Synthesis of proteophosphoglycans of Leishmania major and Leishmania mexicana . J. Org. Chem. . 70 . 5 . 1691–7 . March 2005 . 15730289 . 10.1021/jo048443z.
2. Web site: 14 December 2017 . Leishmaniasis . 30 October 2023 . Centers for Disease Control and Prevention.