[Clinical research progress in stroke-associated pneumonia]

Stroke-associated pneumonia (SAP) is a spectrum of pulmonary infections in non-mechanical ventilation patients within 7 days of stroke. SAP is one of the most common complications after stroke, with an incidence of 7%-38%, which is significantly associated with poor prognosis of stroke. Stroke-induced immune-depression syndrome (SIDS) is one of the main pathogenesis of SAP, which is closely related to autoimmune, sympathetic nervous system (SNS), hypothalamic-pituitary-adrenalin axis (HPA axis), parasympathetic nervous system (PNS), and damage-related molecular patterns (DAMPs). It is unclear how the lungs and brain interact during the development of SAP. Some clinical studies have found that some clinical indicators such as monocyte human leukocyte antigen-DR (mHLA-DR), neutrophil to lymphocyte ratio (NLR) and heart rate variability (HRV) can be used to predict SAP occurrence. Old age, male, and diabetes are currently considered risk factors for SAP. Furthermore, a variety of SAP risk scales such as A2DS2 scale (age, atrial fibrillation, dysphagia, gender and stroke severity), preventive antibacterial therapy in acute ischemic stroke (PANTHERIS) scale, acute ischemic stroke-associated pneumonia scale (AIS-APS), and ISAN scale (pre-stroke independence, gender, age, and stroke severity) have been developed. According to the opinion of Pneumonia in Stroke Consensus in 2015, it is recommended to use the modified Centers for Disease Control and Prevention (CDC) pneumonia clinical diagnostic criteria for the diagnosis of SAP. Prevention of SAP is the most important part of clinical practice. Preventive antibiotics are not recommended, and once SAP is diagnosed, the antibiotic strategies should be followed. Neuroprotective and anti-inflammatory treatments are still being studied.