Optimization of LipL32 PCR assay for increased sensitivity in diagnosing leptospirosis.
Early diagnosis of leptospirosis in humans is critical with regard to initiation of appropriate treatment; however, the gold standard serological test cannot detect antibodies until nearly a week after symptom onset. PCR has been shown to be sensitive and specific in the early phase of leptospirosis. Previously, we developed and validated a TaqMan PCR assay targeting lipL32. We reoptimized and validated this assay using PerfeCTa® qPCR ToughMix®, Low ROX™ (Quanta Biosciences, Gaithersburg, MD, USA). For optimization with the new mix, the final primer concentrations were increased from 0.5 μmol/L to 0.9 μmol/L compared to our previous assay, and the probe concentration increased from 0.1 μmol/L to 0.125 μmol/L. This newly optimized assay resulted in a lower limit of detection and increased diagnostic sensitivity. Here, we present the performance data of the improved assay and describe several clinical cases that were initially negative but tested positive using the optimized assay.
Bacterial Special Pathogens Branch, Division of High-Consequence Pathogens and Pathology, Centers for Disease Control and Prevention, 1600 Clifton Road NE, Atlanta, GA, USA. Electronic address: rgalloway@cdc.gov.
Renee L
RL
Galloway
Bacterial Special Pathogens Branch, Division of High-Consequence Pathogens and Pathology, Centers for Disease Control and Prevention, 1600 Clifton Road NE, Atlanta, GA, USA.
Alex R
AR
Hoffmaster
D000293:Adolescent; D000328:Adult; D006801:Humans; D007922:Leptospirosis / Q000175:diagnosis*; D008297:Male; D025202:Molecular Diagnostic Techniques / Q000379:methods*; D016133:Polymerase Chain Reaction / Q000379:methods*; D012680:Sensitivity and Specificity; D055815:Young Adult
Diagnosis; Leptospirosis; Real time PCR