Leshmaniasis Agglutination, Serum (LAB9619)
More sensitive and rapid PCR with species resolution replaces serology and culture in the diagnosis of leishmaniasis.
- Leishmaniasis is caused by Leishmania spp, protozoan parasites that infect the skin and mucosal surfaces (cutaneous leishmaniasis) or bone marrow and internal organs (visceral leishmaniasis). Leishmania is transmitted by the bite of sandflies and can be found in Texas, Mexico, South America, Central America, Africa, Asia, Middle East, and southern Europe. Lesions first form at the site of the sandfly bite, though the incubation period can be a few days to months to years. Therefore, travel and exposure history—such as outdoor activities in endemic areas—is crucial.
- The primary diagnostic method for leishmaniasis is histopathology. PCR testing, which can be performed on plasma, bone marrow, or unpreserved tissue (e.g., skin punch biopsies for cutaneous leishmaniasis), is available as a send-out test to the Centers for Disease Control and Prevention (CDC) with a turnaround time of approximately three weeks. The CDC exclusively performs PCR for leishmaniasis diagnosis. For visceral leishmaniasis, where patients often present with symptoms such as fever, weight loss, splenomegaly, hepatomegaly, and anemia, serologic testing may provide additional diagnostic value.
- Serologic testing is not recommended for cutaneous leishmaniasis as antibody responses may not be detectable in this form of disease but may be helpful in the diagnosis of visceral leishmaniasis.
- Skin lesions may mimic other skin conditions, such as squamous cell cancer and other infectious disease like leprosy and trypanosomiasis which overlap in geographic distribution.
- Leishmaniasis is typically associated with travel to endemic areas, however, Texas has recently been labelled by the CDC to be endemic for cutaneous leishmaniasis.
- Diagnosis of leishmaniasis should be made in the presence of clinical symptoms, exposure history, and testing which includes surgical pathology, PCR, and serology (visceral leishmaniasis only).
- Species-level identification may give guidance on treatment; therefore, PCR is highly recommended for both cutaneous and visceral leishmaniasis.
- Centers for Disease Control and Prevention. 2024. Leishmaniasis. Available at: https://www.cdc.gov/dpdx/leishmaniasis/index.html.
- Aronson N, Herwaldt BL, Libman M, Pearson R, Lopez-Velez R, Weina P, Carvalho EM, Ephros M, Jeronimo S, Magill A. Diagnosis and Treatment of Leishmaniasis: Clinical Practice Guidelines by the Infectious Diseases Society of America (IDSA) and the American Society of Tropical Medicine and Hygiene (ASTMH). Clin Infect Dis. 2016 Dec 15;63(12):e202-e264. doi: 10.1093/cid/ciw670.
- McIlwee BE, Weis SE, Hosler GA. Incidence of Endemic Human Cutaneous Leishmaniasis in the United States. JAMA Dermatol. 2018 Sep 1;154(9):1032-1039. doi: 10.1001/jamadermatol.2018.2133.
Written By: Tina Bui-Bullock, PhD
Reviewed By: Rebekah Dumm, PhD
Last Edited: 2024-12-07
Last Reviewed: 2024-12-07