Fine Andrew M, Wong John B, Fraser Hamish S F, Fleisher Gary R, Mandl Kenneth D
Division of Emergency Medicine, Children's Hospital Boston, Harvard Medical School, Boston, MA 02115, USA.
Ann Emerg Med. 2004 Mar;43(3):318-28. doi: 10.1016/j.annemergmed.2003.09.007.
We analyze the risks and benefits of alternative treatment strategies for non-septic-appearing febrile patients with influenza-like illnesses and possible exposure to anthrax.
We used a decision analytic model to evaluate 6 testing and treatment strategies in an emergency department. Patients were non-septic-appearing and had influenza-like illnesses but low likelihood of exposure to anthrax. The following interventions were used: (1) no empiric antibiotics; (2) blood culture and treatment only if the result was positive; (3) rapid testing for influenza and, for those who tested negative, treatment with 60 days of ciprofloxacin; (4) a two-test strategy in which all patients were first tested for influenza; those who tested negative had a blood culture test and were treated empirically with ciprofloxacin for 3 days while waiting for blood culture results; (5) culture test for all patients and treatment with ciprofloxacin for up to 3 days while waiting for blood culture results; and (6) treatment of all patients with ciprofloxacin empirically for 60 days. Main outcome measures were deaths, complications from anthrax, adverse events from ciprofloxacin, and ciprofloxacin patient-days.
For nonzero probabilities of anthrax, patient mortality was always lowest in the strategies in which all patients were treated empirically for anthrax either for 60 days or for 3 days pending blood culture results. These strategies, however, were associated with more morbidity (more ciprofloxacin patient-days and more antibiotic adverse events) than were strategies without empiric treatment. The numbers of adverse events and antibiotic patient-days were reduced substantially with the two-test strategy, in which patients with influenza were identified early and not treated. In general, for probabilities of anthrax equaling or exceeding 2%, treating all patients empirically for 60 days was best, but for probabilities between 0.1% and 2%, the sensitivity of blood culture for anthrax determined the optimal strategy: when the sensitivity exceeded 95%, a short course of empiric ciprofloxacin until blood culture results became available was best, but for sensitivities below 95%, more aggressive empiric antibiotics use was warranted. The proportion of patients with influenza in the community affected the choice of strategy, so that seasonal variation exists.
During influenza season, our findings support rapid testing for influenza, followed by empiric treatment for anthrax pending blood culture results for those who test negative for influenza. Our results help to highlight the importance of developing rapid and sensitive tests for anthrax and of developing improved surveillance and methods to calculate the previous probability of attacks.
我们分析了针对疑似感染炭疽但无脓毒症表现的流感样疾病患者的替代治疗策略的风险和益处。
我们使用决策分析模型来评估急诊科的6种检测和治疗策略。患者无脓毒症表现，患有流感样疾病，但接触炭疽的可能性较低。采用了以下干预措施：（1）不使用经验性抗生素；（2）仅在血培养结果呈阳性时进行血培养和治疗；（3）快速检测流感，对检测结果为阴性的患者，给予60天环丙沙星治疗；（4）双检测策略，即所有患者首先检测流感；检测结果为阴性的患者进行血培养检测，并在等待血培养结果期间接受3天环丙沙星经验性治疗；（5）对所有患者进行培养检测，并在等待血培养结果期间给予环丙沙星治疗最多3天；（6）对所有患者给予60天环丙沙星经验性治疗。主要结局指标为死亡、炭疽并发症、环丙沙星不良事件以及环丙沙星使用天数。
对于炭疽存在非零概率的情况，在所有患者接受60天或等待血培养结果期间接受3天炭疽经验性治疗的策略中，患者死亡率始终最低。然而，这些策略与无经验性治疗的策略相比，发病率更高（环丙沙星使用天数更多，抗生素不良事件更多）。双检测策略可显著减少不良事件数量和抗生素使用天数，在该策略中，流感患者能被早期识别且不接受治疗。一般来说，对于炭疽概率等于或超过2%的情况，对所有患者进行60天经验性治疗最佳，但对于概率在0.1%至2%之间的情况，炭疽血培养的敏感性决定了最佳策略：当敏感性超过95%时，在血培养结果出来之前给予短期环丙沙星经验性治疗最佳，但对于敏感性低于95%的情况，则需要更积极地使用经验性抗生素。社区中流感患者的比例会影响策略的选择，因此存在季节性变化。
在流感季节，我们的研究结果支持快速检测流感，对于流感检测结果为阴性的患者，在等待血培养结果期间给予炭疽经验性治疗。我们的结果有助于凸显开发快速、灵敏的炭疽检测方法以及改进监测和计算既往袭击概率方法的重要性。
