The objective of the present study was to evaluate the diagnostic performance of a noninvasive assay, conjunctival swab (CS) nested-PCR (n-PCR), for diagnosing canine leishmaniasis (CanL) in different stages of infection in comparison to the performance of the indirect immunofluorescence antibody test (IFAT), lymph node microscopy, and buffy coat n-PCR. To this end, we performed a cross-sectional survey among 253 nonselected dogs in areas of endemicity in central Italy. We also performed a longitudinal study of CS n-PCR among 20 sick dogs undergoing antileishmanial treatment. In the first study, among the 72 animals that were positive by at least one test (28.45%), CS n-PCR showed the best relative performance (76.38%), with a high concordance in comparison to standard IFAT serology (0.75). The highest positivity rates using CS n-PCR were found in asymptomatic infected dogs (84.2%) and sick dogs (77.8%); however, the sensitivity of the assay was not associated with the presence of clinical signs. In the follow-up study on treated sick dogs, CS n-PCR was the most sensitive assay, with promising prognostic value for relapses. The univariate analysis of risk factors for CanL based on CS n-PCR findings showed a significant correlation with age (P0.012), breed size (P0.026), habitat (P4.9104), and previous therapy (P0.014). Overall, the results indicated that CS n-PCR was the most sensitive assay of the less invasive diagnostic methods and could represent a good option for the early and simple diagnosis of CanL infection in asymptomatic animals and for monitoring relapses in drug-treated dogs.
Diagnostic value of conjunctival swab sampling associated with nested-PCR for different categories of dogs naturally exposed to Leishmania infantum infection
VERONESI, FABRIZIA;ANTOGNONI, Maria Teresa;ONOFRI, Andrea;PIERGILI FIORETTI, Daniela;
2012
Abstract
The objective of the present study was to evaluate the diagnostic performance of a noninvasive assay, conjunctival swab (CS) nested-PCR (n-PCR), for diagnosing canine leishmaniasis (CanL) in different stages of infection in comparison to the performance of the indirect immunofluorescence antibody test (IFAT), lymph node microscopy, and buffy coat n-PCR. To this end, we performed a cross-sectional survey among 253 nonselected dogs in areas of endemicity in central Italy. We also performed a longitudinal study of CS n-PCR among 20 sick dogs undergoing antileishmanial treatment. In the first study, among the 72 animals that were positive by at least one test (28.45%), CS n-PCR showed the best relative performance (76.38%), with a high concordance in comparison to standard IFAT serology (0.75). The highest positivity rates using CS n-PCR were found in asymptomatic infected dogs (84.2%) and sick dogs (77.8%); however, the sensitivity of the assay was not associated with the presence of clinical signs. In the follow-up study on treated sick dogs, CS n-PCR was the most sensitive assay, with promising prognostic value for relapses. The univariate analysis of risk factors for CanL based on CS n-PCR findings showed a significant correlation with age (P0.012), breed size (P0.026), habitat (P4.9104), and previous therapy (P0.014). Overall, the results indicated that CS n-PCR was the most sensitive assay of the less invasive diagnostic methods and could represent a good option for the early and simple diagnosis of CanL infection in asymptomatic animals and for monitoring relapses in drug-treated dogs.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
