Pathogenic colonization of the stomach in enterally fed elderly patients: Comparing percutaneous endoscopic gastrostomy with nasogastric tube

Abstract

Objectives: To compare the gastric juice microbiota of older people fed through a percutaneous endoscopic gastrostomy tube (PEG) with that of those fed through a nasogastric tube (NGT).

Design: Prospective comparative study.

Setting: Nursing and skilled nursing wards.

Participants: Fifty-four elderly PEG-fed and 52 NGT-fed patients.

Measurements: Cultures from the oropharynx and the gastric juice.

Results: Pathogenic bacteria were isolated from the oropharynxes of 44% of the PEG-fed patients and 54% of the NGT-fed patients. The most frequent gram-negative bacilli isolated from the oropharynx were Proteus spp. (13-21%) and Pseudomonas aeruginosa (13-18%), with no significant difference between the groups. Isolation rates from the gastric juice were significantly more frequent in the NGT-fed patients than in the PEG-fed patients for Proteus spp. (4% vs 23%), Escherichia coli (6% vs 21%), and mixed flora (11% vs 27%). Significant correlation was found between high gastric pH and the isolation of bacteria in both groups (correlation coefficient = 0.58, P < .001).

Conclusion: Gastric juice of PEG-fed patients harbors pathogenic bacteria in significant numbers. No significant difference was noted with respect to the rate of isolation of pathogenic bacteria from the oropharynx between the groups. Major bacterial pathogens, such as P. aeruginosa and Proteus spp., were isolated significantly more from the gastric juice of NGT-fed patients. These results support the view that a bidirectional spread pattern of pathogens may take place in NGT-fed patients.