Diagnostic accuracy of reused Pronto Dry® test and CLOtest® in the detection of Helicobacter pylori infection

Abstract

BackgroundUnchanged substrate in a negative rapid urease test may be reused to detect Helicobacter pylori (H. pylori). This could potentially reduce costs and wastage in low prevalence and resource-poor settings. We thus aimed to investigate the diagnostic accuracy of reused Pronto Dry® and CLOtest® kits, comparing this to the use of new Pronto Dry® test kits and histopathological evaluation of gastric mucosal biopsies.MethodsUsing a cross-sectional study design, subjects who presented for upper endoscopy due to various non-emergent causes had gastric biopsies obtained at three adjacent sites. Biopsy samples were tested for H. pylori using a reused Pronto Dry® test, a reused CLOtest®, a new Pronto Dry® test and histopathological examination. Concordance rates, sensitivity, specificity, positive predictive value (PPV), negative predictive value (NPV) and diagnostic accuracy were then determined.ResultsA total of 410 subjects were recruited. The sensitivity and diagnostic accuracy of reused Pronto Dry® tests were 72.60 % (95 % CI, 61.44 – 81.51) and 94.15 % (95 % CI, 91.44 – 96.04) respectively. For reused CLOtests®, the sensitivity and diagnostic accuracy were 93.15 % (95 % CI 85.95 – 97.04) and 98.29 % (95 % CI 96.52 – 99.17) respectively. There were more true positives for new and reused Pronto Dry® pallets as compared to new and reused CLOtests® when comparing colour change within 30 min vs. 31–60 min (P < 0.001 and P = 0.7 respectively).ConclusionNegative Pronto Dry® and CLOtest® kits may be reused in a low prevalence setting where cost issues remain paramount. Reused CLOtest® kits have better accuracy than reused Pronto Dry® tests. Reused Pronto Dry® tests however have a more rapid colour change whilst maintaining diagnostic accuracy.

Diagnostic of Helicobacter pylori infection

“…In order to further decrease the cost of this test, in countries where the cost issue is of paramount importance, Jamaludin et al . tested the possibility to re‐use negative urease tests!…”

“…According to these results, PPI consumption should be stopped at least 12 days before performing RUT or culture. 22 In order to further decrease the cost of this test, in countries where the cost issue is of paramount importance, Jamaludin et al 23 tested the possibility to re-use negative urease tests! It turned out that re-used CLOtests ® were able to maintain their accuracy in comparison to histopathology.…”

Recent Advances in Colorimetric Tests for the Detection of Infectious Diseases and Antimicrobial Resistance

“…In addition to the detection time of Pyloritek ® , that of Hp One ® and Pronto Dry ® is about 1 h, while the CLO test ® and Hp Fast ® take 4-24 h for detection response. The anthocyanin test produces the colorimetric response in less than 1 h [50,54,55].…”