An HIV positive patient presenting a clinical picture of visceral
leishmaniasis co-infection was submitted to a bone marrow aspiration after
admission to hospital. Amastigotes forms were seen in the bone marrow
aspirate and the parasite grew in culture as promastigotes. Molecular
analyses showed that the flagellates isolated did not belong to the genera
Leishmania, Trypanosoma or Sauroleishmania. It was not
possible to establish infection in laboratory animals. In vitro
culture of mouse peritoneal macrophages revealed the invasion of the host
cells by the flagellates and their killing 48 hr after infection.
Opportunistic infection with an insect trypanosomatid was suspected.
Further hybridization analyses against a pannel of different monoxenous and
heteroxenous trypanosomatids showed kDNA cross-homology with Leptomonas
pulexsimulantis a trypanosomatid found in the dog's flea. {P}