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

Abstract

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.

Laboratory techniques for diagnosing Giardia parasite in dogs in Mosul City, Iraq

“…And it turned out that the parasite diagnosed with this technique and study is close to the type of Giardia lamblia, which is the most common and found in dogs. The results of the current study are in agreement with the findings of ( (Symeonidou et al,2020) They confirmed that the results of the microscopic examination and the rapid test gave a sensitivity rate of 58.6% and 86.2, respectively, and a specificity of 100%. The reason for the difference may be due to the intermittent shedding of cysts from infected dogs ranging from one to three days, so the examination of samples must be repeated at least three times.…”

“…It was found through the current results that the rapid immune test technique (Rapid test) recorded a diagnosis rate of the Giardia parasite amounted to 14.2%. The results of the current study agreed with what was reported by (Alharbi et al,2020;Symeonidou et al,2020) They confirmed that the rapid test technique is easy to perform to detect Giardia infection and increases the efficiency of laboratory diagnostic techniques in addition to reducing time. The results of the current study to determine the sensitivity and specificity of the rapid test and microscopic examination of dogs infected with Giardia parasite showed a sensitivity rate of 19% and a specificity of 100%.…”

Toxocara cati and Other Parasitic Enteropathogens: More Commonly Found in Owned Cats with Gastrointestinal Signs Than in Clinically Healthy Ones

“…was more frequently found in cats with diarrheic feces [6,43,44]. The rate of infection with G. duodenalis in cats is likely to be underestimated in this study, as the use of the flotation method has less sensitivity and a bigger probability of false-negative results in comparison with the more recommended assays such as PCR, ELISA, and immunochromatographic tests [45]. Therefore, an accurate frequency of feline giardiosis should be assessed, especially in diarrheic cats.…”

Protozoan Parasites in Adult Dairy Small Ruminants and Potential Predictors for Their Presence in Faecal Samples

“…Moreover, the identification of the lack of a main building on the farm as the only significant predictor for the presence of Giardia cysts in samples from goats ( Table 5 ) could not be associated with a plausible explanation of clinical significance. In any case, the difficulties associated with an accurate Giardia diagnosis, arising from the intermittent excretion of the parasite [ 36 , 37 ], present challenges for the accurate detection of infection status.…”