First Isolation of Leishmania from Northern Thailand: Case Report, Identification as Leishmania martiniquensis and Phylogenetic Position within the Leishmania enriettii Complex

Abstract

Since 1996, there have been several case reports of autochthonous visceral leishmaniasis in Thailand. Here we report a case in a 52-year-old Thai male from northern Thailand, who presented with subacute fever, huge splenomegaly and pancytopenia. Bone marrow aspiration revealed numerous amastigotes within macrophages. Isolation of Leishmania LSCM1 into culture and DNA sequence analysis (ribosomal RNA ITS-1 and large subunit of RNA polymerase II) revealed the parasites to be members of the Leishmania enriettii complex, and apparently identical to L. martiniquensis previously reported from the Caribbean island of Martinique. This is the first report of visceral leishmaniasis caused by L. martiniquensis from the region. Moreover, the majority of parasites previously identified as “L. siamensis” also appear to be L. martiniquensis.

Disseminated Autochthonous Dermal Leishmaniasis Caused by Leishmania siamensis (PCM2 Trang) in a Patient from Central Thailand Infected with Human Immunodeficiency Virus

“…JX898938) and all other strains except PCM2 Trang were L. martiniquensis (PG lineage), as previously stated from the Martinique island. 6 This reflected that L. martiniquensis is the most common cause of autochthonous leishmaniasis in Thailand. Therefore, we can draw conclusion that autochthonous leishmaniasis in Thailand caused by two species of Leishmania: L. martiniquensis and L. siamensis.…”

“…Although L. martiniquensis has worldwide distribution, our current strain appeared more restricted to Thailand. 6 However, due to small number of PCM2 cases, further reports need to be collected for further clarification of various strains of Leishmania.…”

“…Therefore, another PCR and DNA sequencing were performed using primer specific to Leishmania for its identification. 6,9 Sequences from two independent loci were examined: the ITS-1 region of the 18S ribosomal RNA gene and the large subunit of RNAPolII. The large subunit of RNAPolII sequences of our parasite appeared to be 1,181/1,184 base pairs (99%) identical to L. siamensis previously reported (GenBank accession no.…”

“…KM820664) while ITS-1 sequence showed 282/295 base pairs (96%) similarity (JX195640). 6 GenBank accession nos. for the new sequences are KX347438 for ITS-1 and KX347439 for RNAPolII.…”

“…Until recently, it has been evident that most of the so-called L. siamensis are Leishmania martiniquensis. 6 To date, there has been only one published case of PCM2 in southern Thailand. 7 Here we report, for the first time, L. siamensis (PCM2 Trang isolate) from a patient living in central Thailand.…”