INVESTIGADORES
GIL Jose Fernando
artículos
Título:
Molecular identification of Leishmania spp. DNA from archived Giemsa-stained slides of patients from Salta, Argentina
Autor/es:
ALMAZAN, MC; HOYOS, CL; KROLEWIECKI, AJ; CAJAL, P; COPA, GN; FLEITAS, P; BARROSO, P; MARCO, JD; NASSER, JR; GIL, JF
Revista:
AMERICAN JOURNAL OF TROPICAL MEDICINE AND HYGIENE
Editorial:
AMER SOC TROP MED & HYGIENE
Referencias:
Lugar: Stanford; Año: 2018
ISSN:
0002-9637
Resumen:
Cutaneous leishmaniasis is endemic in Salta province, which belongs to the northwest ofArgentina.Leishmania spp. DNA fromGiemsa-stained slides of up to 12 years in storage of patients from Salta wascharacterized through PCR-Restriction Fragment Length Polymorphism (RFLP). Onehundred smears, positive for microscopy classified in a semiquantitative scalefor amastigote density, were analyzed. Also, Leishmanin skin test (LST) resultswere considered. DNA extraction was done applying lysis buffer with proteinaseK, and then DNA was amplified with ribosomal internal transcribed spacer 1(ITS1) primers.PCR products were digested with HaeIII enzyme. All PCR positive smears (74/100)belonged to Viannia subgenus. Astatistically significant directly proportional relationship betweensemiquantitative microscopy and PCR results was detected. All patients had LSTpositive results (induration ≥ 5 mm), and the smears of those with smallerinduration (LST < 19 mm) gave a higher proportion of positive PCR results.This study determined that smear age did not affect PCR positivity, whichallows retrospective analyzes and suggests smears might be useful for molecularcomplementary diagnosis in suspicious cases. Since Leishmania. (Viannia) braziliensis is the main circulatingspecies in the study area, determining Vianniasubgenus in all analyzed samples confirms previous findings. PCR positivityshowed statistically significant differences according to semiquantitativemicroscopy, highlighting the importance of parasite burden in the diagnosticsensitivity of the method. Being that smears of patients with smaller LSTinduration were more positive in PCR, a negative smear from patients withpositive LST response, but < 19 mm, could actually represent a falsenegative result.