## 4 Clinical Impact and Current Evidence  
As with any diagnostic testing, the indication should be inferred in light of local epidemiological considerations and the clinical presentation. Current reviews do not universally recommend diagnostic multiplex testing in every patient with suspected diarrheal diseases [54]. Our literature search yielded only 13 studies reporting on the use of multiplex PCR panels for AGE in tropical settings. Critically, many of these studies were conducted in tropical regions, but the multiplex analysis was performed by study partners, e.g., in Europe [15; 17]. In addition, these studies were not designed to assess the clinical impact of multiplex testing on patient care and public health. This certainly limits the interpretation of the usability of multiplex testing in tropical settings. In industrialized regions, a study evaluated the impact of another platform, the FilmArray GIP, on length of stay and patient isolation. This study found that patients spent considerable time without appropriate isolation methods in the hospital, whereas other patients were placed under contact precautions without cause [53]. Another study has shown that costs for the clinical laboratory increased, but overall, there were savings for the hospital [55]. [PERSON] et al. reported that 65% of positive results were from pathogens not specifically ordered by the treating physician [56]. The clinical impact is much harder to assess in resource-limited settings where it became apparent that in children, numerous pathogens can be detected in cases with diarrhea as well as in asymptomatic controls [17]. Another study on infectious diarrhea including adult patients with persistent diarrhea and asymptomatic controls came to a similar conclusion in that positive results need confirmation of an active infection state [5]. These findings emphasize that it requires careful analysis of the local setting (i.e., patient population: adult versus pediatric, ambulatory versus in-hospital, immune status/previous antibiotic treatment, travel associated) and to evaluate the implementation of new methods in the local laboratory. The integrated stewardship concept addresses these concerns and might help in decision making when implementing syndromic panels [57]. For some patients, a more tailored approach would be more effective but not possible with the fixed combinations delivered by the manufacturers. It seems advisable to develop algorithms, which patient should be tested using which method. This apparently needs a cross-sectional and collaborative effort of all involved partners within a hospital or in primary care. However, in industrialized settings and even more so in resource-limited settings, there are still limited evidence-based data available to support a favorable benefit-risk ratio. In a meta-analysis including 162 norovirus outbreaks, implementation of infection control measures reduced patient case counts and length of hospital stay 0.6 and 0.7 fold, respectively, emphasizing the value of rapid and accurate diagnostics [58]. However, these data lack the economic impact, which is of particular relevance for low-income settings. \begin{table}
\begin{tabular}{c c c c c c} \hline \hline
**Virus** & **Mode of** & **Target Population** & **Incubation** & **Clinical Significance** & **Vacination** \\ \hline \multirow{4}{*}{Adenovirus} & \multirow{4}{*}{
\begin{tabular}{c} Fecal–oral; food \\ and water \\ \end{tabular} } & & & & Moderate to severe & \\  & & & & gastroenteritis, including & \\  & & & & hospital-acquired & \\  & & & children; adults & \(>\)7 & infections; possible & \\  & & & & persistence in & \\  & & & & immunocompromised & \\  & & & & patients & \\ \hline \hline \end{tabular}
\end{table} 
Table 3: _Cont._To conclude, although syndromic panels have been available for some time, there are still no general recommendations for the routine use of multiplex syndromic panels in patients presenting with AGE neither in industrialized nor in resource-poor settings.