title: Evaluation of urine for Leishmania infantum DNA detection by real-time quantitative PCR.
abstract: The availability of some sorts of biological samples which require noninvasive collection methods has led to an even greater interest in applying molecular biology on visceral leishmaniasis (VL) diagnosis, since these samples increase the safety and comfort of both patients and health professionals. In this context, this work aimed to evaluate the suitability of the urine as a specimen for Leishmania infantum kinetoplast DNA detection by real-time quantitative PCR (qPCR). Subsequent to the reproducibility analysis, the detection limit of the qPCR assay was set at 5fg (~0.025 parasites) per μL of urine. From the comparative analysis performed with a set of diagnostic criteria (serological and molecular reference tests), concordance value of 96.08% was obtained (VL-suspected and HIV/AIDS patients, n=51) (P>0.05). Kappa coefficient (95% CI) indicated a good agreement between the test and the set of diagnostic criteria (k=0.778±0.151). The detection of Leishmania DNA in urine by qPCR was possible in untreated individuals, and in those with or without suggestive renal impairment. Fast depletion of the parasite's DNA in urine after treatment (from one dose of meglumine antimoniate) was suggested by negative qPCR results, thus indicating it as a potential alternative specimen to follow up the efficacy of therapeutic approaches. Even when evaluated in a clinically heterogeneous set of patients, the urine showed good prospect as sample for VL diagnosis by qPCR, also indicating a good negative predictive value for untreated suspected patients.
authors.affiliation: Aggeu Magalhães Research Center, Av. Moraes Rego, Cidade Universitária, CEP 50670-420 Recife, PE, Brazil; Public Health's Central Laboratory Dr. Milton Bezerra Sobral (LACEN-PE), Praça Oswaldo Cruz, S/N, Soledade, CEP 50050-215 Recife, PE, Brazil. Electronic address: romulops12@gmail.com.
authors.forename: Rômulo
authors.initials: R
authors.lastname: Pessoa-E-Silva
authors.affiliation: Aggeu Magalhães Research Center, Av. Moraes Rego, Cidade Universitária, CEP 50670-420 Recife, PE, Brazil. Electronic address: laystrajano@gmail.com.
authors.forename: Lays Adrianne
authors.initials: LA
authors.lastname: Mendonça Trajano-Silva
authors.affiliation: Aggeu Magalhães Research Center, Av. Moraes Rego, Cidade Universitária, CEP 50670-420 Recife, PE, Brazil. Electronic address: almerice@cpqam.fiocruz.br.
authors.forename: Maria Almerice
authors.initials: MA
authors.lastname: Lopes da Silva
authors.affiliation: Aggeu Magalhães Research Center, Av. Moraes Rego, Cidade Universitária, CEP 50670-420 Recife, PE, Brazil; Public Health's Central Laboratory Dr. Milton Bezerra Sobral (LACEN-PE), Praça Oswaldo Cruz, S/N, Soledade, CEP 50050-215 Recife, PE, Brazil. Electronic address: sueniaaa@hotmail.com.
authors.forename: Suênia
authors.initials: S
authors.lastname: da Cunha Gonçalves-de-Albuquerque
authors.affiliation: Aggeu Magalhães Research Center, Av. Moraes Rego, Cidade Universitária, CEP 50670-420 Recife, PE, Brazil. Electronic address: taynacgoes@hotmail.com.
authors.forename: Tayná Correia
authors.initials: TC
authors.lastname: de Goes
authors.affiliation: Aggeu Magalhães Research Center, Av. Moraes Rego, Cidade Universitária, CEP 50670-420 Recife, PE, Brazil. Electronic address: rayanacarla_m@hotmail.com.
authors.forename: Rayana Carla
authors.initials: RC
authors.lastname: Silva de Morais
authors.affiliation: Aggeu Magalhães Research Center, Av. Moraes Rego, Cidade Universitária, CEP 50670-420 Recife, PE, Brazil. Electronic address: fabio@cpqam.fiocruz.br.
authors.forename: Fábio
authors.initials: F
authors.lastname: Lopes de Melo
authors.affiliation: Aggeu Magalhães Research Center, Av. Moraes Rego, Cidade Universitária, CEP 50670-420 Recife, PE, Brazil. Electronic address: mp@cpqam.fiocruz.br.
authors.forename: Milena
authors.initials: M
authors.lastname: de Paiva-Cavalcanti
mesh_terms: D000163:Acquired Immunodeficiency Syndrome / Q000150:complications; D000293:Adolescent; D000328:Adult; D000368:Aged; D001938:Brazil; D002648:Child; D003404:Creatinine / Q000097:blood / Q000652:urine; D018105:DNA, Kinetoplast / Q000097:blood / Q000235:genetics / Q000302:isolation & purification* / Q000652:urine*; D016054:DNA, Protozoan / Q000097:blood / Q000302:isolation & purification / Q000652:urine; D005260:Female; D006678:HIV / Q000472:pathogenicity; D006801:Humans; D018314:Leishmania infantum / Q000235:genetics* / Q000472:pathogenicity; D007898:Leishmaniasis, Visceral / Q000097:blood / Q000175:diagnosis* / Q000469:parasitology / Q000652:urine*; D008297:Male; D008875:Middle Aged; D025202:Molecular Diagnostic Techniques / Q000379:methods*; D060888:Real-Time Polymerase Chain Reaction / Q000379:methods*; D015203:Reproducibility of Results; D014508:Urea / Q000097:blood / Q000652:urine; D014556:Urine / Q000469:parasitology*; D055815:Young Adult
chemical_list: D018105:DNA, Kinetoplast; D016054:DNA, Protozoan; D014508:Urea; D003404:Creatinine
keywords: Diagnosis; Real-time quantitative PCR; Urine; Visceral leishmaniasis