The association between oral bacteria, the cough reflex and pneumonia in patients with acute stroke and suspected dysphagia

Abstract

Objective: To establish how oral bacteria are related to cough sensitivity and pneumonia in a clinical stroke population.Background: Stroke patients are at risk of colonisation by respiratory pathogens due, in part, to sudden discontinuation of effective oral hygiene. When combined with reduced cough reflex sensitivity, aspiration of contaminated oropharyngeal contents and can lead to pneumonia. Relationships between oral bacteria, cough sensitivity and pneumonia have not been established. Materials and methods:A total of 102 patients with acute stroke underwent saliva sampling and cough reflex testing at admission to hospital, discharge and one month.A qPCR assay compared levels of bacteria in saliva. Pneumonia events were recorded.Results: Relative levels of bacteria were lowest at admission to hospital (6.04 × 10 −6 ).There was a slight (non-significant) increase in bacterial levels at discharge (1.69 × 10 −2 , P = .73). By one month, bacterial levels had significantly increased (9.17 × 10 −2 ) relative to admission [P < .001] and discharge [P < .001]. Pseudomonas aeruginosa, Klebsiella pneumoniae and Escherichia coli are not typically found in healthy mouths, yet were detected in 22% of patients during hospitalisation. Combined bacterial levels measured at one month was associated with pneumonia (P = .004) but there was no relationship to cough sensitivity.Conclusion: Acute stroke patients were at increased risk of colonisation from respiratory pathogens throughout their recovery. The presence of these pathogens in saliva at one month was associated with adverse respiratory events. Data support the development of protocols to explore risk factors and sequelae of microbiological changes in stroke. K E Y W O R D SAspiration Pneumonia, CVA, oral hygiene, qPCR | 387 PERRY Et al.

Aspiration Risk Factors, Microbiology, and Empiric Antibiotics for Patients Hospitalized With Community-Acquired Pneumonia

“…Consequently, a higher prevalence of P. aeruginosa and Enterobacteriaceae (other GNB) was seen in severe ACAP patients. As the oral cavity is considered the principal source of pathogens responsible for aspiration pneumonia, our results suggest a shift in the oral flora of severe ACAP patients (12,40,41).…”

“…Microbiology data from patients with other comorbid conditions suggested that P. aeruginosa, K. pneumoniae, and E. coli were frequently isolated from oral samples (40,42). These results should alert clinicians of the need to appropriately cover against GNB in severe ACAP, especially if risk factors for pseudomonas are present.…”

Diagnosis and treatment of neurogenic dysphagia – S1 guideline of the German Society of Neurology

“…Poor oral health in combination with dysphagia has been identified in particular in stroke and geriatric patients as a risk factor for aspiration pneumonia [ 206 , 207 ]. In addition to periodontitis, gingivitis, plaque formation and caries, respiratory pathogens such as Staphylococcus aureus, Streptococcus pneumoniae, Haemophilus influenzae, Klebsiella oxytoca, Pseudomonas aeruginosa and Escherichia coli have frequently been detected in the oral cavity of these patients [ 208 ].…”

Stroke and Pneumonia: Mechanisms, Risk Factors, Management, and Prevention

“…The study also demonstrated that the change in bacteria levels is associated with the development of pneumonia. The researchers concluded that the presence of respiratory flora in patients’ mouths within 48 hours of a stroke is clinically significant [ 36 ].…”