Shah R M, Kaji A V, Ostrum B J, Friedman A C
Department of Radiology, Medical College of Pennsylvania, Philadelphia 19129, USA.
Radiographics. 1997 Jan-Feb;17(1):47-58; discussion 59-61. doi: 10.1148/radiographics.17.1.9017798.
Specific infections and neoplasms that are complications of acquired immunodeficiency syndrome (AIDS) occur within various CD4 lymphocyte count ranges. Knowledge of how these counts correlate with radiographic appearances of these entities can limit the differential diagnosis because certain conditions are uncommon above a specific count. In patients with CD4 lymphocyte counts above 200 cells/mm3 and radiographic findings of cavitary and noncavitary consolidation, bacterial pneumonia and Mycobacterium tuberculosis are the major diagnostic considerations. As the CD4 lymphocyte count falls, these infections are still common; however, cavitation is seen less frequently with Mycobacterium tuberculosis, and unusual bacterial infections, including those caused by Rhodococcus equi and Nocardia asteroides, should be considered. In patients with counts below 200 cells/mm3, Pneumocystis carinii pneumonia is the most common infection, usually manifesting radiographically as a reticular interstitial pattern. At CD4 lymphocyte counts of 50-200 cells/mm3, disseminated fungal infection and Kaposi sarcoma become prevalent. In patients with advanced AIDS and counts below 50 cells/mm3, radiographic nodular or reticular patterns may indicate AIDS-related lymphoma and cytomegalovirus and Mycobacterium avium-intracellulare infections. When CD4 lymphocyte counts are applied to interpretation of chest radiographs in AIDS patients, the working differential diagnosis of a radiographic pattern can be tailored to the clinical situation of a given patient.
获得性免疫缺陷综合征（AIDS）的并发症——特定感染和肿瘤，会在不同的CD4淋巴细胞计数范围内出现。了解这些计数与这些病症的影像学表现之间的关联，有助于缩小鉴别诊断范围，因为某些病症在特定计数以上并不常见。对于CD4淋巴细胞计数高于200个细胞/mm³且有肺空洞和非肺空洞实变影像学表现的患者，细菌性肺炎和肺结核是主要的诊断考虑因素。随着CD4淋巴细胞计数下降，这些感染仍然常见；然而，肺结核出现空洞的频率降低，应考虑包括马红球菌和星形诺卡菌引起的不常见细菌感染。对于计数低于200个细胞/mm³的患者，卡氏肺孢子虫肺炎是最常见的感染，通常在影像学上表现为网状间质模式。在CD4淋巴细胞计数为50 - 200个细胞/mm³时，播散性真菌感染和卡波西肉瘤变得普遍。对于晚期AIDS且计数低于50个细胞/mm³的患者，影像学上的结节状或网状模式可能提示与AIDS相关的淋巴瘤以及巨细胞病毒和鸟分枝杆菌复合群感染。当将CD4淋巴细胞计数用于解释AIDS患者的胸部X线片时，影像学模式的有效鉴别诊断可以根据特定患者的临床情况进行调整。
