Persistence of leishmania parasites in scars after clinical cure of American cutaneous leishmaniasis: is there a sterile cure?
BACKGROUND
It is uncertain whether Leishmania parasites ever disappear after clinical cure of American cutaneous leishmaniasis (ACL). Recently, sensitive molecular techniques have allowed the identification of Leishmania parasites directly in specimens from patients' scars.


METHODS
Scars of 32 patients from northeastern Brazil who were treated and clinically cured of ACL were analyzed by use of polymerase chain reaction (PCR), culture, and histopathologic examination.


RESULTS
DNA specific for Leishmania (Viannia) was detected in scars of 30 (93.7%) of 32 patients. In specimens from 3 of the scars, Leishmania parasites could be isolated by culture; PCR results also were positive for those 3 specimens. No parasites were found by histopathologic examination, and fibrotic alterations were present in all cases, with slight inflammatory foci observed in 4 of the cases studied.


CONCLUSIONS
The results suggest that clinical cure of ACL is rarely associated with sterile cure. The implications of persistence of parasites for the clinical evolution, relapse, and transmission of leishmaniasis deserves further studies, particularly with the increasing incidence of coinfection with leishmaniasis and acquired immunodeficiency syndrome.
Departamento de Dermatologia, Universidade Federal de Pernambuco, Recife, Brazil.
Mitzi G
MG
Mendonça
Maria E F
ME
de Brito
Eduardo H G
EH
Rodrigues
Valdir
V
Bandeira
Márcio L
ML
Jardim
Frederico G C
FG
Abath
D000293:Adolescent; D000328:Adult; D000818:Animals; D002921:Cicatrix / Q000469:parasitology* / Q000473:pathology; D016054:DNA, Protozoan / Q000032:analysis; D005260:Female; D006801:Humans; D007892:Leishmania braziliensis / Q000302:isolation & purification*; D016773:Leishmaniasis, Cutaneous / Q000276:immunology / Q000469:parasitology*; D008297:Male; D008875:Middle Aged
D016054:DNA, Protozoan