Fluorescence-based Immunochromatographic strip test for the detection of hyoscyamine

Hyoscyamine (HSM) which act as antagonists of acetylcholine muscarinic receptor and can induce a variety of distinct toxic syndromes in mammals (anti-cholinergic poisoning) which hazardous in human health. Therefore, it...

Rapid on-site diagnosis of canine giardiosis: time versus performance

Background Infections by protozoans of the genus Giardia are a common cause of diarrhea in dogs. Canine giardiosis constitutes a disease with a zoonotic potential; however, it is often underestimated due to its challenging diagnosis. The objective of the study was to assess the diagnostic performance of an immunochromatographic strip test (SpeedTMGiardia, Virbac, France) comparing it with microscopy (zinc sulfate flotation) by utilizing the combination of an enzyme immunoassay (ProSpecTTMGiardia EZ Microplate Assay, Oxoid Ltd., UK) and the PCR as the gold standard. A positive result in both ELISA and PCR was set as the gold standard. Methods Initially, fecal samples from dogs with clinical signs compatible with giardiosis were tested with the SpeedTMGiardia test and separated into two groups of 50 samples each: group A (positive) and group B (negative). Thereafter, all samples were examined by zinc sulfate centrifugal flotation technique and assayed by the ProSpecTTMGiardia Microplate Assay and PCR. The performance of the SpeedTMGiardia and zinc sulfate centrifugal flotation tests were calculated estimating sensitivity, specificity, and positive and negative likelihood ratio; the chi-square and McNemar tests were used for the comparison of the two methods. Results Giardia cysts were not detected by microscopy in 16 out of the 50 samples (32%) of group A and in none of group B samples. Eight out of 50 samples in group B (16%) were tested positive both with the ProSpecTTMGiardia Microplate Assay and PCR. Fecal examination with the SpeedTMGiardia test was more sensitive (86.2%) than the parasitological method (58.6%, P < 0.001) while the specificity of both methods was 100%. Conclusions The SpeedTMGiardia test is an easy-to-perform diagnostic method for the detection of Giardia spp., which can increase laboratory efficiency by reducing time and cost and decrease underdiagnosis of Giardia spp. infections. This immunochromatographic strip test may be routinely exploited when a rapid and reliable diagnosis is required, other diagnostic techniques are unavailable and microscopy expertise is inefficient. In negative dogs with compatible clinical signs of giardiosis, it is recommended either to repeat the exam or proceed with further ELISA and PCR testing.

Simple Strategy for Rapid and Sensitive Detection of 2019 novel coronavirus Based on Antibody

Objectives: Since December 2019, acute respiratory disease due to 2019 novel coronavirus emerged in Wuhan city and rapidly spread throughout China. Real-time RT-PCR is widely deployed in diagnostic virology. However, the positive detection rates of RT-PCR are only 30% to 50%. Therefore, we propose a simple strategy for rapidly and sensitively detecting the IgM/IgG antibody against 2019-nCoV using a colloidal gold-based immunochromatographic strip test.Methods A total of 41 clinically 2019-nCoV suspected cases (23 males and 18 females) were enrolled. The sensitivity of colloidal gold-based immunochromatographic strip test and of RT-PCR were compared and evaluated. McNemar’s test was used to compare the detection rate of both assays (P<0.05).Results: The Antibody was detected in 63.4% (26/41) of blood specimens using the assay. In contrast, the 2019-nCoV was detected in 46.3% (19/41) of nasal and pharyngeal swab specimens using the RT-PCR assays. The detection rate obtained by this assay was markedly higher than that obtained by the RT-PCR assays (P=0.039)Conclusion: This detection assay exhibits a higher detection sensitivity than RT-PCR. More important, the assay shows the benefits of easy operation and setup. We believe that the sensitive and time-saving approach may be used as an auxiliary diagnostic tool for 2019-nCoV detection and virus screening and confirmation.