Aetiology of traveller’s diarrhoea: evaluation of a multiplex PCR tool to detect different enteropathogens

Abstract

Traveller's diarrhoea (TD) is the most common illness reported in international travellers. TD is caused by a wide range of pathogens, including bacteria, viruses and parasites. Multiplex PCR assays can be especially useful for studying the aetiology of TD. The first objective of this study was to evaluate the utility of the commercially available multiplex PCR (xTAG(®) Gastrointestinal Pathogen Panel (GPP)) for the diagnosis of TD. A total of 185 stool specimens obtained from 174 patients were processed using the GPP assay. This test detected 86 pathogens in 67 stool samples (67/185, 36.2%). Sixteen pathogens out of 86 were also detected by routine testing. The remaining pathogens (n = 70) required further confirmation by alternative techniques. Finally, 60 out of 70 pathogens were confirmed. The second objective of this study was to analyse the aetiology of TD based on the results obtained by the GPP test and routine methods. The primary pathogens causing TD were Shigella (24.2%) followed by enterotoxigenic Escherichia coli (ETEC) (23.2%), enteroaggregative E. coli (14.7%) and Giardia (13.7%). Significant regional differences were observed for ETEC with 19.4% of TD cases acquired in Africa, 11.3% in Asia and none in South Central (SC) America (p 0.01), Giardia was found in 1.5% of cases among those who had travelled to Africa, 14.1% of those who had travelled to Asia and 3% of those who had travelled to SC America (p 0.01). In conclusion, the GPP test improved the detection of enteropathogens and allowed better assessment of the aetiology of TD.

Multiplex tests to identify gastrointestinal bacteria, viruses and parasites in people with suspected infectious gastroenteritis: a systematic review and economic analysis

“…11,12,[20][21][22][23]25,[29][30][31][32][33][34]38,39 However, only four studies reported outcomes of verification by pathogen. 20,23,25,30 Study design Table 7 characterises the design heterogeneity among the studies reported, which should be noted when considering the pooled study outcomes.…”

“…Only one study 11 differentiated between hospital-based samples (from children admitted with suspected viral gastroenteritis and children presenting to the emergency room) and community-based samples [adult and child travellers whose samples were submitted by general practitioners (GPs)]; the study population consisted of children and travellers only. Seven studies 19,22,26,27,29,35,39 reported the setting sufficiently to allow judgement on the origin of the infection (hospital vs. community). The majority of studies 11,12,20,21,[23][24][25]28,[30][31][32][33][34][36][37][38] reported recruitment of hospitalised patients, for which a mixed population should be assumed (in terms of origin of infection) as it is unclear at what point in time during hospitalisation each infection occurred.…”

“…Only one study was identified as a community study, set in Côte d'Ivoire. 19 Subgroups of interest were reported in 10 studies 11,19,20,22,25,26,29,35,36,39 and, of these, one considered travellers only 39 and two considered immunocompromised patients only. 22,26 Children aged < 5 years were not considered separately in any study, but the proportion of children aged < 5 years was reported in six studies 11,19,20,25,35,36 and ranged from 2% to 40% of the total study population.…”

“…However, one study reported study-level results for hospital-and community-acquired infections. 27 Country of study Eleven studies 11,22,[27][28][29][30]32,35,[37][38][39] included participants from European countries, including three studies from the UK. 27,30,32 One study was multinational, covering North America and Europe, 21 eight studies were from North America, 12,20,25,26,31,33,34,36 two were from Asia 23,24 and one was from Africa.…”

“…Only two studies 19,32 were rated as having high concern for the applicability with respect to the index tests (because of deviations from the manufacturer's instructions: timing, storage or extraction). The applicability of a comparator was of low concern for six studies (26.1%) 12,21,26,27,29,36 and of high concern for 16 studies (69.6%), 11,19,20,[22][23][24][25]28,[30][31][32][33][34][37][38][39] in which the comparator methods were not consistent with those specified for the PHE algorithm. The applicability concern for a reference standard (i.e.…”