Griffiths R I, Hyman C L, McFarlane S I, Saurina G R, Anderson J E, O'Brien T, Popper C, McGrath M M, Herbert R J, Sierra M F
Covance Health Economics and Outcomes Services Inc, Washington, DC 20005-3934, USA.
Infect Control Hosp Epidemiol. 1998 Oct;19(10):747-53. doi: 10.1086/647718.
To compare resource use by diagnostic outcome among hospital admissions during which tuberculosis (TB) was suspected.
Retrospective study based on chart review and microbiology laboratory data.
The department of medicine in a municipal hospital serving central Brooklyn, New York.
We identified all adult admissions in 1993 during which TB was suspected. We assigned each admission to one of four mutually exclusive groups defined by the results of microbiological tests (acid-fast bacilli [AFB] smear and culture): culture-positive and smear-positive (C+S+); culture-positive and smear-negative (C+S-); culture-negative and smear-positive (C-S+); or culture-negative and smear-negative (C-S-). Each admission was divided into two separate periods to which the utilization of medical resources was assigned: the diagnostic and the postdiagnostic periods, which were separated by the date of receipt of the first definitive culture report.
Data on 519 admissions (93 C+S+; 57 C+S-; 30 C-S+; and 339 C-S-) were analyzed. Although C+S+ were more likely than other groups to have an admitting diagnosis of TB, approximately one quarter of the admissions without TB (C-S+, C-S-) were admitted with the principal diagnosis of TB. For the four groups, C+S+, C+S-, C-S+, and C-S-, the respective rates of TB isolation and anti-TB treatment, and median lengths of isolation were 98%, 87%, and 34 days; 74%, 74%, and 7 days; 83%, 83%, and 15 days; and 44%, 29%, and 0 days. During the diagnostic period, the rate and length of isolation were similar in the AFB-smear-positive groups (C+S+ and C-S+). We estimated that admissions without culture-proven TB (C-S+ and C-S-) accounted for 3,174 (36%) of the 8,712 days of TB isolation expended and for 65% of the 16,671 days of anti-TB treatment. The vast majority of this resource consumption (2,737 [86%] of 3,174 days of isolation) occurred during the diagnostic period before a definitive culture result was known.
Our results suggest that prolonged diagnostic uncertainty and misclassification of cases due to false-positive and false-negative smears are associated with substantial medical-resource consumption. New diagnostic modalities that reduce the period of diagnostic uncertainty could reduce the utilization of resources later found to be unnecessary.
比较疑似结核病（TB）的住院患者中不同诊断结果的资源使用情况。
基于病历审查和微生物实验室数据的回顾性研究。
纽约布鲁克林市中心一家市级医院的内科。
我们确定了1993年所有疑似结核病的成年住院患者。根据微生物检测结果（抗酸杆菌[AFB]涂片和培养）将每位患者分配到四个相互排斥的组之一：培养阳性且涂片阳性（C+S+）；培养阳性且涂片阴性（C+S-）；培养阴性且涂片阳性（C-S+）；或培养阴性且涂片阴性（C-S-）。每位患者被分为两个独立的时期，并分配医疗资源的使用情况：诊断期和诊断后期，以收到第一份明确培养报告的日期为界。
分析了519例住院患者的数据（93例C+S+；57例C+S-；30例C-S+；3例39例C-S-）。虽然C+S+组比其他组更有可能以结核病作为入院诊断，但约四分之一没有结核病的住院患者（C-S+、C-S-）以结核病作为主要诊断入院。对于C+S+、C+S-、C-S+和C-S-这四组，各自的结核菌分离率、抗结核治疗率和隔离中位数分别为98%、87%和34天；74%、74%和7天；83%、83%和15天；44%、29%和0天。在诊断期，AFB涂片阳性组（C+S+和C-S+）的隔离率和隔离时间相似。我们估计，未得到培养证实的结核病住院患者（C-S+和C-S-）占结核病隔离总天数8712天的3174天（36%），占抗结核治疗总天数16671天的65%。这种资源消耗的绝大部分（3174天隔离中的2737天[86%]）发生在明确培养结果之前的诊断期。
我们的结果表明，由于涂片假阳性和假阴性导致的诊断不确定性延长和病例错误分类与大量医疗资源消耗有关。减少诊断不确定期的新诊断方法可以减少后来发现不必要的资源利用。
