Neuman Mark I, Harper Marvin B
Division of Emergency Medicine, Children's Hospital, Boston, Massachusetts 02115, USA.
Pediatrics. 2003 Dec;112(6 Pt 1):1279-82. doi: 10.1542/peds.112.6.1279.
Streptococcus pneumoniae remains the most common cause of occult bacteremia, bacterial pneumonia, and meningitis in young febrile children. We sought to determine the utility of a pneumococcal urine antigen assay among young febrile children at varying risk of invasive pneumococcal disease.
We prospectively enrolled 5 groups of children, 3 months to 5 years of age, who presented to an urban pediatric emergency department or hospital-based clinic between January 1, 2000, and April 1, 2001. The groups enrolled included 1) children with pneumococcal bacteremia, 2) febrile children with pneumonia, 3) febrile nonbacteremic children with leukocytosis, 4) febrile nonbacteremic children with normal white blood cell (WBC) counts, and 5) afebrile children with no evidence of current or recent bacterial infection.
Of 346 children enrolled, positive assay results were found in 23 (95%) of 24 with pneumococcal bacteremia (95% confidence interval [CI]: 77%-100%), 47 (76%) of 62 with lobar pneumonia (95% CI: 63%-85%), 28 (15%) of 181 nonbacteremic children with fever (95% CI: 11%-22%) with no difference among patients with elevated WBC counts (18%; 95% CI: 11%-27%) compared with those with normal WBC counts (11%; 95% CI: 5%-21%), and 6 of 79 patients without fever (8%; 95% CI: 3%-16%).
This S pneumoniae antigen detection assay demonstrated high sensitivity for proven (bacteremic) and suspected (focal pneumonia) invasive pneumococcal infections. The rate of false-positive test results among febrile children without identified pneumococcal infection is approximately 15%. Although not ideal, this combination of sensitivity and specificity compares favorably with other available tests, such as the WBC or absolute neutrophil count used to screen children for clinically unsuspected pneumococcal infections.
肺炎链球菌仍是发热儿童隐匿性菌血症、细菌性肺炎和脑膜炎的最常见病因。我们试图确定肺炎球菌尿抗原检测在不同侵袭性肺炎球菌病风险的发热儿童中的效用。
我们前瞻性地纳入了5组年龄在3个月至5岁之间的儿童，这些儿童于2000年1月1日至2001年4月1日期间前往城市儿科急诊科或医院门诊就诊。纳入的组包括：1）肺炎球菌菌血症患儿；2）发热性肺炎患儿；3）发热性非菌血症性白细胞增多症患儿；4）发热性非菌血症性白细胞计数正常的患儿；5）无当前或近期细菌感染证据的无热患儿。
在纳入的346名儿童中，24例肺炎球菌菌血症患儿中有23例（95%）检测结果呈阳性（95%置信区间[CI]：77%-100%），62例大叶性肺炎患儿中有47例（76%）（95%CI：63%-85%），181例发热性非菌血症患儿中有28例（15%）（95%CI：11%-22%），白细胞计数升高的患儿（18%；95%CI：11%-27%）与白细胞计数正常的患儿（11%；95%CI：5%-21%）之间无差异，79例无热患儿中有6例（8%）（95%CI：3%-16%）。
这种肺炎链球菌抗原检测方法对已证实（菌血症）和疑似（局灶性肺炎）的侵袭性肺炎球菌感染具有高敏感性。在未确诊肺炎球菌感染的发热儿童中，假阳性检测结果的发生率约为15%。尽管不理想，但这种敏感性和特异性的组合与其他可用检测方法（如用于筛查临床未怀疑肺炎球菌感染儿童的白细胞或绝对中性粒细胞计数）相比具有优势。
