Comparison among FLOTAC, Kato-Katz and formalin ether concentration techniques for diagnosis of intestinal parasitic infections in school children in an Egyptian rural setting

Abstract

The study aimed to compare the diagnostic performance of the Kato-Katz, formalin ether concentration method (FECM) and FLOTAC using Sheather's sugar solution (FS1), saturated sodium chloride (FS2) and zinc sulfate (FS7) for the diagnosis of intestinal parasites among school children, focusing on Schistosoma mansoni. Ninety fecal samples were examined using the above mentioned techniques. The overall infection rate was 87.7%. Concerning protozoa, FLOTAC (FS1 and FS2) and FECM detected nearly equal infection rates (43.3% and 44.4%, respectively) with very good agreement. Kato-Katz diagnosed the highest helminthic infection rate (57.8%) followed by FLOTAC FS7 (44.4%) and FECM showed the lowest helminthic infection rate (27.7%). As for S. mansoni, Kato-Katz showed an infection rate of 38.8% vs FLOTAC (22.2%) and FECM (11.1%). The three techniques detected the same infection rate (11.1%) with egg counts more than 72 eggs/gram of feces. The FLOTAC sensitivity and accuracy for the diagnosis of protozoa were 97% and 99%, respectively. Regarding helminths diagnosis, FLOTAC technique showed higher sensitivity (77%) and accuracy (87%) compared to FECM (48% sensitivity and 70% accuracy). Therefore, FLOTAC can be used synchronously or in replacement to other diagnostic techniques. This can strategically impact future control programmes of intestinal parasitic infections in limited resources settings.

Evaluation of Commercial Concentration Methods for Microscopic Diagnosis of Protozoa and Helminths in Human Stool Samples in a Non-Endemic Area

“…This discrepancy can also be attributed to the type of concentration method, as the authors compared a flotation method to a diphasic method. The mini-FLOTAC technique has been evaluated in several field studies in endemic countries, but it was often compared to the Kato-Katz method, which is rarely used in northern countries [10,11].…”

Performance of loop-mediated isothermal amplification (LAMP) for detection of Schistosoma mansoni infection compared with Kato–Katz and real-time PCR

“…mansoni . A melting curve was performed to confirm the specificity of the amplicon products by increasing temperature slowly from 72°C to 95°C for one min, then at 55°C for 30 s and finally at 95°C for 30 s (Ten Hove et al ., 2008; Cnops et al ., 2013; Allam et al ., 2018; Allam et al ., 2021a,b).…”

“…Aside from the microscopic Kato–Katz technique, many Schistosoma mansoni diagnostic methods including Percoll, FLOTAC technique on faecal samples (Allam et al ., 2015; Allam et al ., 2021b) and the point-of-care circulating cathodic antigen assay (POC-CCA) in urine samples had been used in Egypt and elsewhere (Allam et al ., 2018; Okoyo et al ., 2018). POC-CCA was reported to display high accuracy and performance in moderate- and high-transmission areas but lacked specificity in low endemic settings in Brazil (Peralta et al ., 2018; Graeff-Teixeira et al ., 2021).…”

Evidence of reduced academic performance among school children with helminth infection independent of nutritional status

“…Preserved stool samples were processed using the formalin-ether concentration method (11). Brie y, a portion of stool weighing approximately 2g was placed in a separate stool container and mixed with 10ml of 10% formalin, ltered through two layers of gauze into a 15ml centrifuge tube and centrifuged at 2000 rpm for 2 min.…”