On the importance of developing a new generation of breath tests forHelicobacter pyloridetection

Abstract

State-of-the-art methods for non-invasive detection of the Helicobacter pylori (H. pylori) infection have been considered. A reported global tendency towards a non-decreasing prevalence of H. pylori worldwide could be co-influenced by the functional limitations of urea breath tests (UBTs), currently preferred for the non-invasive recognition of H. pylori in a clinical setting. Namely, the UBTs can demonstrate false-positive or false-negative results. Within this context, limitations of conventional clinically exploited H. pylori tests have been discussed to justify the existing need for the development of a new generation of breath tests for the detection of H. pylori and the differentiation of pathogenic and non-pathogenic strains of the bacterium. This paper presents the results of a pilot clinical study aimed at evaluating the development and diagnostic potential of a new method based on the detection of the non-urease products of H. pylori vital activity in exhaled gas. The characteristics of breath of adolescents with H. pylori-positive and H. pylori-negative functional dyspepsia, together with a consideration of the cytotoxin-associated gene A (CagA) status of H. pylori-positive subjects, have been determined for the first time using innovative point-contact nanosensor devices based on salts of the organic conductor tetracyanoquinodimethane (TCNQ). The clinical and diagnostic relevance of the response curves of the point-contact sensors was assessed. It was found that the recovery time of the point-contact sensors has a diagnostic value for differentiation of the H. pylori-associated peptic ulcer disease. The diagnostically significant elongation of the recovery time was even more pronounced in patients infected with CagA-positive H. pylori strains compared to the CagA-negative patients. Taking into account the operation of the point-contact sensors in the real-time mode, the obtained results are essential prerequisites for the development of a fast and portable breath test for non-invasive detection of cytotoxic CagA strains of H. pylori infection. The relaxation time of the point-contact nanosensors could be selected as a diagnostic criterion for non-invasive determination of H. pylori-associated destructive lesions of the gastroduodenal area in adolescents, using the point-contact spectroscopic concept of breath analysis. This can subsequently be implemented into a 'test-and-treat' approach for the management of uninvestigated dyspepsia in populations with a high prevalence of H. pylori (according to the Maastricht III and IV Consensus recommendations).

Diagnostic of Helicobacter pylori infection

“…Such tests could represent lower cost, 47 and 2, a new point-contact nanosensor device using salts of the organic conductor tetracyanoquinodimethane was assessed and could be used in a portable breath analyzer. 48 A portable mass spectrometer was also tested in comparison to a fixed apparatus. An agreement was observed in only 39/45 patients tested, indicating that improvement is still necessary.…”

“…New tests were also developed: 1, the ammonia breath test showed different breath ammonia levels at baseline and after urea ingestion in 10 of the 14 H. pylori positive patients. Such tests could represent lower cost, and 2, a new point‐contact nanosensor device using salts of the organic conductor tetracyanoquinodimethane was assessed and could be used in a portable breath analyzer …”

Selective detection of complex gas mixtures using point contacts: concept, method and tools

“…Special attention was paid to the identification and detailing of clinical symptoms based on the medical history, the presence of a family history of digestive system lesions, and disease duration, in accordance with the Rome IV criteria [ 33 ]. All patients received a full medical examination identical to the previously described procedures [ 11 ].…”

“…In sensor studies, the quantum properties of Yanson point contacts solve the problems that could not be solved when analogues were used to measure the variation in electrical conductance. This can be exemplified by the new quantum mechanism of selective detection in gaseous and liquid media [ 10 ] and by the possibility of real-time detection of carcinogenic strains of Helicobacter pylori [ 11 ].…”

“…Point-contact sensors can detect single substances [ 31 – 32 ] and also obtain an integrated profile of a complex gas mixture [ 4 , 11 ]. This profile contains information about the complete set of energy interactions that take place in the point contact/ breath system.…”