Heussel C P, Kauczor H U, Heussel G, Fischer B, Mildenberger P, Thelen M
Department of Radiology, Johannes Gutenberg University, Mainz, Germany.
AJR Am J Roentgenol. 1997 Nov;169(5):1347-53. doi: 10.2214/ajr.169.5.9353456.
The purpose of this study was to evaluate the usefulness of thin-section CT for early detection of pneumonia in neutropenic patients with an unknown site of infection and normal or nonspecific findings on chest radiographs.
Eighty-seven patients with febrile neutropenia that persisted for more than 2 days despite empiric antibiotic treatment underwent 146 prospective examinations. If findings on chest radiographs were normal (n = 126) or nonspecific (n = 20), thin-section CT (1-mm collimation, 10-mm increment) was done. If thin-section CT scans showed opacities, bronchoalveolar lavage was recommended.
Findings on chest radiographs were nonspecific for pneumonia in 20 (14%) of 146 cases, and CT findings in those cases were suggestive of pneumonia. Microorganisms were detected in 11 of those 20 cases. Seven of the 11 cases were not optimally treated before CT diagnosis, the other four were sufficiently treated. Findings on chest radiographs and thin-section CT scans were normal in 56 (38%) of 146 cases. In 70 (48%) of 146 cases, findings on chest radiographs were normal, whereas findings on thin-section CT scans were suggestive of pneumonia. Microorganisms were detected in 30 of the 70 cases. Nineteen of 30 cases were not optimally treated before CT, whereas the other 11 cases were sufficiently treated before CT. In 22 (31%) of these 70 cases, an opacity was observed on the chest radiograph during the 7 days after the CT study. Only three (5%) of 56 pneumonias occurred during the first 7 days after thin-section CT studies with normal findings (p < .005). Additional risk factors for pneumonia occurring later that were detectable on chest radiographs were poorly defined nodules (p < .05), consolidation (p < .05), and younger age (p < .05).
Thin-section CT scans show findings suggestive of pneumonia about 5 days earlier than chest radiographs show suggestive findings. When thin-section CT scans show findings suggestive of pneumonia, the probability of pneumonia being detected on chest radiographs during the 7-day follow-up is 31%, whereas the probability is only 5% when the findings on the prior thin-section CT scan were normal (p < .005). All neutropenic patients with fever of unknown origin and normal findings on chest radiographs should be examined with thin-section CT.
本研究旨在评估薄层CT对感染部位不明且胸部X线片表现正常或非特异性的中性粒细胞减少患者早期肺炎检测的有用性。
87例发热性中性粒细胞减少患者，尽管接受了经验性抗生素治疗，但发热仍持续超过2天，共进行了146次前瞻性检查。如果胸部X线片表现正常（n = 126）或非特异性（n = 20），则进行薄层CT检查（准直1 mm，层厚10 mm）。如果薄层CT扫描显示有肺部实变影，则建议进行支气管肺泡灌洗。
146例中有20例（14%）胸部X线片对肺炎的表现不具有特异性，而这些病例的CT表现提示肺炎。这20例中有11例检测到微生物。这11例中有7例在CT诊断前未得到最佳治疗，另外4例得到了充分治疗。146例中有56例（38%）胸部X线片和薄层CT扫描表现正常。146例中有70例（48%）胸部X线片表现正常，而薄层CT扫描表现提示肺炎。这70例中有30例检测到微生物。30例中有19例在CT检查前未得到最佳治疗，而另外11例在CT检查前得到了充分治疗。在这70例中的22例（31%）中，CT检查后7天内胸部X线片观察到肺部实变影。在薄层CT检查结果正常后的最初7天内，仅56例肺炎中有3例（5%）发生肺炎（p <.005）。胸部X线片上可检测到的肺炎后期发生的其他危险因素为边界不清的结节（p <.05）、实变（p <.05）和较年轻（p <.05）。
薄层CT扫描显示提示肺炎的表现比胸部X线片早约5天。当薄层CT扫描显示提示肺炎的表现时，7天随访期间胸部X线片检测到肺炎的概率为31%，而先前薄层CT扫描结果正常时该概率仅为5%（p <.005）。所有不明原因发热且胸部X线片表现正常的中性粒细胞减少患者均应进行薄层CT检查。
