Oral opportunistic pathogens in patients with stroke following hospital discharge

Abstract

Oral opportunistic pathogens are associated with nosocomial infections, and are highly prevalent in hospitalized patients with stroke. The time course of oral carriage following discharge from the hospital environment, however, warrants further investigation. Objectives: An observational study was conducted to monitor oral opportunistic pathogens including Staphylococcus aureus, aerobic and facultatively anaerobic Gram negative bacilli (AGNB), and yeasts prior to hospital discharge, and after six months.

Methods: Concentrated oral rinse and imprint samples were collected from patients following stroke in a rehabilitation ward prior to hospital discharge, and six months later, for detection of S. aureus, AGNB, and yeasts. Patients had previously been recruited to an in-hospital oral health promotion program. The development of infectious complications was also monitored following discharge. S. aureus were identified with Staph Slidex Plus. Yeasts and AGNB were identified with ID32C and API20E/API20NE, respectively.

Results: A total of 52 patients were reviewed at six months. While AGNB prevalence prior to discharge (80.8%) was significantly reduced (p=0.001), half of the patients (51.9%) remained colonized at six months. No significant changes were observed in percentage frequencies of S. aureus (51.9%) and yeast (55.8%) detected prior to discharge. Viable counts (cfu/ml) of AGNB (p<0.001) and yeast (p=0.028) were significantly reduced at six months. Pneumonia and subsequent mortality was documented for two patients, in which detectable viable counts of opportunistic pathogens (6.4x105cfu/ml, 3.6x104cfu/ml) were also among the highest observed prior to discharge.

Conclusions: Oral opportunistic pathogens remain highly prevalent in patients with stroke up to six months following hospital discharge. Further evaluation and identification of optimal oral health promotion interventions in this patient group is required.