FilmArray™ GI panel performance for the diagnosis of acute gastroenteritis or hemorragic diarrhea

Abstract

BackgroundAcute gastroenteritis is a common cause of morbidity and mortality in humans worldwide. The rapid and specific identification of infectious agents is crucial for correct patient management. However, diagnosis of acute gastroenteritis is usually performed with diagnostic panels that include only a few pathogens. In the present bicentric study, the diagnostic value of FilmArray™ GI panels was assessed in unformed stool samples of patients with acute gastroenteritis and in a series of samples collected from pediatric patients with heamorragic diarrhea. The clinical performance of the FilmArray™ gastrointestinal (GI) panel was assessed in 168 stool samples collected from patients with either acute gastroenteritis or hemorragic diarrhea. Samples showing discordant results between FilmArray and routine methods were further analyzed with an additional assay.ResultsOverall, the FilmArray™ GI panel detected at least one potential pathogen in 92/168 (54.8%) specimens. In 66/92 (71.8%) samples, only one pathogen was detected, while in 26/92 (28.2%) multiple pathogens were detected.The most frequent pathogens were rotavirus 13.9% (22/168), Campylobacter 10.7% (18/168), Clostridium difficile 9.5% (16/168), and norovirus 8.9% (15/168). Clostridium difficile was identified only in patients with acute gastroenteritis (p < 0.01), while STEC was detected exclusively in patients with hemorragic diarrhea (p < 0.01). In addition, Campylobacter spp., Salmonella spp., EPEC and E. coli producing Shiga-like toxin were more frequently detected in patients with hemorragic diarrhea (p < 0.05). The overall percent agreement calculated in samples was 73.8% and 65.5%, while 34.5% were discordant. After additional confirmatory analyses, the proportion of discordant samples decreased to 7.7%. Rotavirus and astrovirus were the most frequently unconfirmed pathogens.ConclusionIn conclusion, the FilmArray™ GI panel has proved to be a valuable new diagnostic tool for improving the diagnostic efficiency of GI pathogens.

A Gastrointestinal PCR Panel Improves Clinical Management and Lowers Health Care Costs

“…We found that the GI panel had a high (32.8%) positivity rate which was similar to that of other published studies (5)(6)(7)(8). Piralla et al (9) tested 168 adult and pediatric patients with diarrhea and found an overall 54.8% positivity rate, with 28.3% having more than one organism. We found that 24% of positive samples had more than one organism.…”

Molecular versus culture-based testing for gastrointestinal infection

“…As these tests become more prevalent in clinical microbiology laboratories, it is essential that adequate evaluation of molecular tests for the diagnosis of gastrointestinal infections is undertaken. Recent evaluation studies demonstrate that the use of molecular-based diagnostics increases the sensitivity of testing for some enteric pathogens, with overall high negative predictive values [4][5][6][7][8][9][10]. However, the UK National Institute for Health and Care Excellence (NICE) published their diagnostics guidance in January 2017 [11], based on a Diagnostic Assessment Report commissioned by the National Institute of Health Research (NIHR) Health Technology Assessment (HTA) Programme [12].…”

“…The introduction of molecular technologies into a clinical microbiology laboratory, such as multiplex polymerase chain reaction (PCR) assays, can benefit the diagnosis of gastrointestinal infection by facilitating simultaneous detection of pathogens (bacterial, parasitic and viral) directly from faeces. Molecular-based diagnosis gives a laboratory the potential to increase sample throughput, increase the amount of information obtained from a single test and decrease sample turnaround times [4][5][6][7][8][9][10]. Additionally, simple workflows and a reduction in the need for technical expertise are appealing attributes of these diagnostic methods.…”

Detection of Acute Gastroenteritis Agents By Molecular Methods

“…ishalli hastalarda yaptığı bir çalışmada konvansiyonel yöntemlerle %27,7 oranında etken saptarken, multiplex PZR yöntemiyle %66,2 oranında etken saptayabilmişlerdir [4]. Farklı çalışmalarda başka bir multiplex PZR kitiyle etken saptanma oranı %33,0-%62,7 oranında bildirilmiştir [5,6,7,8]. Konvansiyonel yöntemlerle yapılan çalışmalarda gastroenterit etkenleri Hollanda' da %6,4, Amerika Birleşik Devletleri'nde % 8.3, Yeni Zelanda' da %18 olarak saptanmıştır.…”

“…Piralla ve ark. yaptığı çalışmada koenfeksiyon oranı %27,2 olarak bulunmuştur [7]. Bu çalışmadaki koenfeksiyon oranı birçok çalışmaya göre daha azdır (%8,5).…”