Pneumococcal colonisation density: a new marker for disease severity in HIV-infected adults with pneumonia

Objective: A high genomic load of Pneumococcus from blood or cerebrospinal fluid has been associated with increased mortality. We aimed to analyse whether nasopharyngeal colonisation density in HIV-infected patients with community-acquired pneumonia (CAP) is associated with markers of disease severity or poor outcome. Methods: Quantitative lytA real-time PCR was performed on nasopharyngeal swabs in HIV-infected South African adults hospitalised for acute CAP at Chris Hani Baragwanath Hospital, Soweto, South Africa. Pneumonia aetiology was considered pneumococcal if any sputum culture or Gram stain, urinary pneumococcal C-polysaccharide-based antigen, blood culture or whole blood lytA real-time PCR revealed pneumococci. Results: There was a moderate correlation between the mean nasopharyngeal colonisation densities and increasing CURB65 scores among all-cause patients with pneumonia (Spearman correlation coefficient r=0.15, p=0.06) or with the Pitt bacteraemia score among patients with p...研究目的：血液或脑脊液中检出的肺炎链球菌（Pneumococcus）基因组载量较高与死亡率升高相关。本研究旨在分析人类免疫缺陷病毒（HIV）感染合并社区获得性肺炎（Community-Acquired Pneumonia, CAP）患者的鼻咽定植密度，是否与疾病严重程度标志物或不良预后存在关联。 研究方法：针对南非索韦托克里斯·哈尼·巴拉格万特医院收治的因急性CAP住院的HIV感染成年患者，对其鼻咽拭子样本开展lytA实时定量PCR检测。若患者的痰液培养、革兰氏染色、尿液肺炎链球菌C多糖抗原检测、血液培养或全血lytA实时PCR任意一项结果检出肺炎链球菌，则判定该患者的肺炎病因为肺炎链球菌感染。 研究结果：在所有病因的肺炎患者中，鼻咽平均定植密度与CURB65评分升高呈中等程度相关（斯皮尔曼相关系数r=0.15，p=0.06）；在伴p...的患者中，其鼻咽定植密度与Pitt菌血症评分存在关联。