Skip to main content

Table 1 Interpretation and actions suggested after observation of different positivity combinations of the quality controls and Leishmania spp. main target in the triplex PCR reaction

From: Tracking false-negative results in molecular diagnosis: proposal of a triplex-PCR based method for leishmaniasis diagnosis

Result/PCR target positivity Interpretation/meaning Action
G3PD 567 bp (+) Valid results for parasite diagnosis Conclude diagnostic test observation
pUC 316 bp (+)
L. braziliensis 138 bp (+)
G3PD 567 bp (+) Valid results for parasite diagnosis despite small loss of DNA in extraction Conclude diagnostic test observation
pUC 316 bp (-)
L. braziliensis 138 bp (+)
G3PD 567 bp (-) Valid results for parasite diagnosis despite small degradation of sample Conclude diagnostic test observation
pUC 316 bp (+)
L. braziliensis 138 bp (+)
G3PD 567 bp (-) Degradation of DNA sample/presence of PCR inhibitors and/or whole DNA loss during extraction Repeat diagnostic procedure since the blood sample collection
pUC 316 bp (-)
L. braziliensis 138 bp (-)
G3PD 567 bp (-) Degradation of DNA sample before extraction Repeat diagnostic procedure since the blood sample collection
pUC 316 bp (+)
L. braziliensis 138 bp (-)
G3PD 567 bp (+) Significant DNA loss (affecting mainly parasite genome) during extraction process Repeat the DNA extraction procedure
pUC 316 bp (-)
L. braziliensis 138 bp (-)
G3PD 567 bp (+) True negative result for Leishmania detection assured by the positivity of quality controls Conclude diagnostic test observation
pUC 316 bp (+)
L. braziliensis 138 bp (-)