Effects of nasogastric tube on oral microbiome among long-term care patients

Dysbiosis of oral microbiome causes chronic diseases including dental caries and periodontitis, which frequently affects elderly, frail patients receiving long-term care. Severely disabled patients may require nutritional supply via nasogastric (NG) tube, which impacts patients oral condition and possibly microbial composition. However, little is known about the effect of NG tube on oral microbes and its potential ramification. Here, by using 16S rRNA next-generation sequencing, we characterized the tongue microbiome of 27 patients fed with NG tubes and 26 others fed orally. The microbial compositions of NG-tube and oral-feeding patients were substantially different, with more Gram-negative aerobes enriched in the presence of NG tube. Specifically, NG-tube patients presented more opportunistic pathogens like Corynebacterium and Pseudomonas associated with pneumonia, and lower levels of commensal Streptococcus and Veillonella. Together, we present a systematic, high-throughput profiling of oral microbiome with regards to NG tube indwelling, providing empirical evidence for better clinical practice. ImportanceLong-term use of NG tubes on elderly patients often leads to poor oral hygiene and chronic infectious diseases, e.g. periodontitis and tooth decay. More importantly, because patients fed with NG tubes usually have swallowing dysfunctions, they are more likely to suffer from aspiration pneumonia, a life-threatening lung infection caused by inhalation of oral bacteria. Together, clinical implications of chronic NG-tube indwelling are significantly related to oral microbes. Understanding the effects of NG tubes on oral microbiome would generally inform how clinical care should be given, particularly antimicrobial therapy.